Documentation

Imatest IT Instructions

Introduction

Interface Type:
Watch on YouTube.

Imatest IT (Industrial Testing) is a set of Application Programming Interfaces (APIs) that allow developers to access Imatest’s powerful image quality analysis tools in their own custom applications.

Imatest IT is available for 64-bit Windows and Linux, and includes libraries for use with C, C++, Python, .NET (including C# and Visual Basic), and LabVIEW, and also contains standalone executables that can be called from a command line or script. The API libraries perform the exact same calculations as the corresponding GUI-based Imatest Master modules.

Imatest IT is a complete package that includes the module libraries, support documentation, sample code, and complete applications that interface with the modules.

Although Imatest IT operates independently of Imatest Master and Image Sensor, we strongly recommend that IT users have at least one Master or IS installation on site. Imatest Ultimate Edition, which includes both IT and Image Sensor at a significant discount, is the ideal option for most users. As you will see in Step 2 below, setting up your test configuration, an integral part of any IT application, is much easier using Master or IS.

 

Imatest IT Modules

Imatest IT contains sixteen image analysis modules:

SFR – measures MTF and related results from slanted edges SFRplus – measures MTF, lateral chromatic aberration, distortion, tonal response, and much more using Imatest’s highly-automated SFRplus chart
Star – measures MTF and lateral chromatic aberration Colorcheck – measures color accuracy, noise, tonal response, and more from an X-Rite Colorchecker
Stepchart – measures tonal response, gamma, noise, and more from a grayscale stepchart Wedge – measures MTF using hyperbolic wedges
OIS – measures the efficacy of image stabilization Uniformity – measures image uniformity, color shading, and hot/dead pixels from a flat field image
Distortion – measures distortion using a grid or checkerboard pattern eSFR ISO – measures MTF, color accuracy, noise, and tonal response using the ISO 12233:2014 chart
Blemish – measures visually-significant blemishes from a flat field image Dot Pattern – measures distortion and lateral chromatic aberration from a dot grid pattern (I3A CPIQ-compliant)
Multitest – analyzes images of a large variety of test charts for color accuracy, tonal response, noise, SNR (Signal-to-Noise Ratio) and ISO sensitivity Checkerboard – measures MTF, lateral chromatic aberration, and distortion using a checkerboard target
Random – Module that measures texture quality using the spilled coins or random chart SFRreg – measures MTF and lateral chromatic aberration using the SFRreg target

Using Imatest IT

As illustrated in this graphic, working with Imatest IT is a four-step process. Each of these steps is outlined in detail in this article.

Step 1: Prepare Test Environment and Capture Test Targets

Inputs: None
Outputs: Test Image(s)
Imatest’s analysis modules require correctly framed and properly lit images of test targets. Once your test environment is properly set up, capture images of the required test targets for the modules you will be using.

Step 2: Configure INI File w/ Test Image(s)

Inputs: Test Image(s)
Outputs: INI File(s)
Using a sampling of the test images captured in Step 1, use Imatest Master or Image Sensor to analyze the image files, choosing the options required for your application, and setting the Regions of Interest (ROIs) for your charts. Once everything is ready, export the INI file and keep it with your application source files.

In Imatest 5.0+ you can use the  Save ini file for  button in the Imatest IT settings window to save an ini file with only the needed sections.

Step 3: Integrate and Call Imatest IT Modules

Inputs: Test Image(s), INI File(s)
Outputs: Analysis Results
Code your application using your preferred programming language and call the module functions with your images and INI file.

Step 4: Process the Results

Inputs: Analysis Results
Outputs: Whatever you need
Load the analysis results and use them however you wish.

 

Installing Imatest IT

If you have not already downloaded Imatest IT, you can do so on the download page.

Next, follow the installation instructions found here.

After Imatest IT has successfully installed, you will need to activate it on your computer. Follow these instructions to activate your node-locked or floating license. If the computer running Imatest IT does not have an internet connection, you can also choose to activate it offline.

Post Installation Tasks

Linux Only – Updating the LD_LIBRARY_PATH

On Linux computers, several paths need to be appended to the LD_LIBRARY_PATH environment variable. To do this, you will need to edit your ~/.bashrc (or similar) file, and include these lines:

export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/usr/local/Imatest/v4.5/IT/bin
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/usr/local/Imatest/v4.5/IT/libs/library/cpp
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/usr/local/MATLAB/MATLAB_Runtime/v901/runtime/glnxa64
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/usr/local/MATLAB/MATLAB_Runtime/v901/bin/glnxa64
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/usr/local/MATLAB/MATLAB_Runtime/v901/sys/os/glnxa64
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/usr/local/MATLAB/MATLAB_Runtime/v901/sys/opengl/lib/glnxa64

For more information on editing environment variables, see this article.

 

(Optional) – Reducing Startup Time w/ the MCR Cache

The first time you use the Imatest IT libraries, they must be unpacked to a temporary directory. This can take several seconds, depending on your system. In some use cases, this can happen on every use, especially if you are using the Imatest IT Acquisition Library.

To prevent the repeated unpacking of the IT libraries, you need to set two more environment variables: MCR_CACHE_ROOT and MCR_CACHE_SIZE. The MCR_CACHE_ROOT variable tells the Matlab Runtime where to extract the Imatest IT libraries. Setting it to a specific location that has write access for all users ensures that this cache will not be deleted by the operating system when it cleans up temporary files. The MCR_CACHE_SIZE variable is the size, in bytes, that the Matlab Runtime cache is allowed to grow to before other libraries are deleted. To keep Imatest IT running at top performance, it should be set to at least 900000000, and will result in much faster startup times for Imatest IT for some users.

Follow the instructions here to add these variables to your environment.
Windows

Variable Name Value
MCR_CACHE_ROOT C:\ProgramData\Imatest\mcr_cache\4.5\IT
MCR_CACHE_SIZE 900000000

Linux

Variable Name Value
MCR_CACHE_ROOT /var/lib/imatest/mcr_cache
MCR_CACHE_SIZE 900000000

 

Other Additional Installation Steps

Select your preferred interface below to see detailed instructions.

Interface Type:

In order for your application to interface with the Imatest IT C or C++ DLLs, your system needs to know where to find them.

There are two ways to make the Imatest IT C or C++ DLLs available to the system:

  • Add the library’s directory to your system’s PATH or LD_LIBRARY_PATH variable (recommended).
  • Copy the DLLs to the same directory as your application.

Adding to the PATH or LD_LIBRARY_PATH variable

Add the following directory to your system’s PATH (Windows) or LD_LIBRARY_PATH (Linux) variable, depending on which interface you will be using. For instructions on how to do this, see Editing System Environment Variables.

Note: Linux users may already have completed this step by following the Additional Installation Steps above, if you are using the C++ library.

Operating System Variable Name Value
Windows PATH C:\Program Files\Imatest\v4.5\IT\libs\library\c
Linux LD_LIBRARY_PATH /usr/local/Imatest/v4.5/IT/libs/library/c
Operating System Variable Name Value
Windows PATH C:\Program Files\Imatest\v4.5\IT\libs\library\cpp
Linux LD_LIBRARY_PATH /usr/local/Imatest/v4.5/IT/libs/library/cpp

Copying the Imatest IT DLLs

If you prefer not to change your PATH or LD_LIBRARY_PATH variables, you can also reference the Imatest IT DLLs by copying them to the same directory as your project’s executable.

Visual Studio users can automate this process by adding a Post-Build Event.

  • In the Solution Explorer, right-click on the project and select Properties.
  • Under Configuration Properties and Build Events, choose Post-Build Event.
  • Add the following to the Command Line box:
    copy /Y "C:\Program Files\Imatest\v4.5\IT\libs\library\c\imatest_library.dll" ";$(TargetDir)"
    
    copy /Y "C:\Program Files\Imatest\v4.5\IT\libs\library\cpp\imatest_library.dll" "$(TargetDir)"
    
  • Repeat these steps for each configuration in your project.

Now, the imatest_library.dll file will be copied to your project’s target directory automatically and will be able to be loaded by your application.

The Imatest IT Python Interface is shipped as a Python module. Before referencing it in your scripts, you will need to install it using Python’s package manager. This must be done on the command line, and requires Administrator access. If you don’t know how to open a Command Prompt with Administrator privileges in Windows, see this helpful article.

Note: Imatest IT only supports Python versions 2.7, 3.3, and 3.4. Python 3.5 support will be available in Imatest IT 5.0, coming soon.

 

First, navigate to the Imatest IT Python library directory.

Windows

cd C:\Program Files\Imatest\v4.5\IT\libs\library\python\

Linux

cd /usr/local/Imatest/v4.5/IT/libs/library/python

Next, run the following command to install the Imatest IT Python module:

Windows (assuming you are running Python 2.7 installed in C:\Python27\)

C:\Python27\python.exe setup.py install

Linux

sudo python setup.py install

You will now be able to reference Imatest IT in your Python scripts using the import statement.

There are no more additional installation steps required to use the Imatest IT .NET libraries.

To simplify calling the Imatest IT EXE programs from the command line or a script file, the Imatest IT bin directory should be part of your PATH environment variable.

Windows In Windows, this is done automatically during installation, but if you are getting errors like “sfr.exe is not recognized as an internal or external command, operable program or batch file” when trying to run the EXE programs, you may need to manually add the bin directory to your PATH environment variable.

Follow these instructions and add C:\Program Files\Imatest\v4.5\IT\bin to the system PATH variable. You will need to open a new command window for the change to take effect.

Linux On Linux systems, you will need to manually add $PATH:/usr/local/Imatest/v4.5/IT/bin to the PATH variable. See these instructions.

Step 1: Prepare Test Environment and Capture Test Targets

Imatest’s analysis modules require correctly framed and properly lit images of test targets to produce accurate results. For information on setting up your image testing environment, see this article.

Imatest offers a wide range of test charts to improve the accuracy of your image analysis.

Step 2: Configure INI File with Test Image(s)

Besides the test image, the other important input for all Imatest IT module functions is an INI configuration file. The INI file contains settings that are used by Imatest modules to describe the input image (such as the ROI [region of interest]), how the analysis should be calculated, and where to write output files. Before using Imatest IT in your application, you will need to configure one or more INI files to customize the analysis for your specific testing needs.

In Imatest 5.0+ you can use the  Save ini file for  button in the Imatest IT settings window to save an ini file with only the needed sections. 

Creating an INI File with Imatest Master or Image Sensor

Imatest IT-specific INI File Settings

First, you will want to configure the Imatest IT-specific settings. Do this by choosing Settings then IT & Pass/Fail Settings… from the main window menu bar. For a detailed explanation of the IT-specific settings found in this window, see this article. After you have made your changes, click OK.

Image Analysis INI File Settings

Once you have an image file of your test target that matches the framing and dimensions of the tests you will run using Imatest IT, analyze it using Imatest Master or Image Sensor with the modules you require. Be sure the image has the same pixel count as the images that will be used in your production environment.

Continue repeating the tests with different settings until you have the results you require.

Exporting the INI File

Once you are configured all of the required IT settings and set up test settings that fulfill your requirements – including the Region of Interest (ROI), calculation details, output files, and folder locations – go back to the main Imatest window, and choose INI File Settings then Save Settings… from the menu bar. Choose a location for the INI file and give it a useful name. This file will be the second input when calling Imatest IT module functions.

Imatest 5.0+:  You can use the Save ini file for button in the Imatest IT settings window to save an ini file with only the needed sections. 

Step 3: Integrate and Call Imatest IT Modules

Now that you have your test images and INI files all prepared, you are ready to integrate your application and analyze the images using Imatest IT’s module functions.

Select your preferred interface below to see detailed instructions.

Interface Type:

Windows (Visual Studio) Project Setup

First, you need to configure your project to be able to find the Imatest IT and Matlab MCR libraries. To do this, right click on the project and choose Properties. Add the following include directories in the sections under Configuration Properties:

Category Property Value
C/C++ / General Additional Include Directories C:\Program Files\MATLAB\MATLAB Runtime\v901\extern\include
C:\Program Files\Imatest\v4.5\IT\libs\library\c
Linker / General Additional Include Directories C:\Program Files\MATLAB\MATLAB Runtime\v901\extern\lib\win64\microsoft
C:\Program Files\Imatest\v4.5\IT\libs\library\c
Linker / Input Additional Dependencies mclmcrrt.lib
imatest_library.lib

Note: Imatest 4.5 and newer only supports 64-bit architectures. You must use the x64 platform configuration when using Imatest IT in your projects. You may need to manually add this platform configuration to your project first. For information on how to do this, see this article.

Initializing the Imatest IT Library

Now that your project references are set up, the next step is to include the imatest_library.h header file. Add this line to the top of your source file:

#include "imatest_library.h"

Next, initialize the Matlab MCR application state by calling mclInitializeApplication(const char **options, int count). Most users can ignore the options and count parameters; just pass in NULL and 0, respectively. The function will return 0 if successful, allowing you to trap errors and handle them gracefully. This should only be called once during the life of your application.

#include "imatest_library.h"

int main()
{
    if (!mclInitializeApplication(NULL,0))
    {
        printf("Error: could not initialize application properly.\n");
        return -1001;
    }

    /// ...
}

The last initialization step is to call imatest_libraryInitialize(). This will prepare the Imatest IT library for use. The function also returns 0 if it is successful.

#include "imatest_library.h"

int main()
{
    if (!mclInitializeApplication(NULL,0))
    {
        printf("Error: could not initialize the Matlab MCR properly.\n");
        return -1001;
    }

    if(!imatest_libraryInitialize())
    {
        printf("Error: could not initialize the Imatest IT library properly.\n");
        return -1002;
    }

    /// ...
}

Calling the Imatest IT C Library Interface

Now that the Matlab MCR and Imatest IT library are all ready to go, the next step is the prepare the arguments that will be passed into the IT module functions. Each of the IT modules has the same method signature (with the exception of OIS). In this example, we will use the sfr function. The signature for the SFR module function looks like this:

bool mlfSfr_shell(int nargout, mxArray** nret, mxArray* inputFile, mxArray* rootDir, mxArray* inputKeys, mxArray* opMode, mxArray* varargin);

The Imatest IT C library encapsulates all input and output arguments inside mxArray types. This is a generic pointer type that can represent any data type. See below for more information on using mxArrays.

The Imatest IT C library parameters are listed here:

Parameter Name Data Type Description
nargout int

The number of expected output arguments. This will always be 1 for the JSON result string.

&nret mxArray** [const char*]

The output object, which will be a string wrapped in an mxArray.

inputFile mxArray* [const char*]

Image file path. A full path name may be used (and is recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If a relative path name is used, the path is relative to your calling program, not the value of the rootDir parameter.
Multiple files can be analyzed by using a wildcard (*) symbol in the path. For example, if the inputFile parameter is “C:\Imatest\iPhone6_*.jpg”, all .jpg files in the folder C:\Imatest with filenames beginning with “iPhone6_” will be analyzed.

rootDir mxArray* [const char*]

Directory containing your INI file. If you do not pass a file path in as the first item in the varargin parameter, then Imatest IT will use a file named imatest-v2.ini found in this directory as your INI configuration.

inputKeys mxArray* [const char*]

This value should always be the string “JSON”. XML output has been deprecated.

opMode mxArray* [const char*]

String containing one of the following operation codes, which tells Imatest IT how to analyze your image(s), and how to read the values contained in the varargin parameter.

If you are supplying your own full path to an INI file, and it is the first item in the varargin collection, then use one of these values: -7, -8, -10, or -17. If your INI file is named imatest-v2.ini and resides in the directory passed in as rootDir, then use one of these values: -5, -6, -9, and -15.

The different opCode values direct how Imatest IT will behave. For more information on the different op modes supported by Imatest IT, see this article.

varargin mxArray* [multiple const char*]

This is a catch all array structure for other parameters required by the various opModes. The contents of this array depend on which op mode you are using, and on how many images you will be processing. For information on how to populate this array, see here.

Working with mxArrays

The Imatest IT C library receives and returns data via mxArray pointers. The Matlab MCR provides helper methods for allocating, interacting with, and deallocating mxArray structures.

Most of the Imatest IT C library input parameters (with the exception of varargin and raw image data passed in when using direct read mode) are strings (const char*) wrapped as mxArrays. You can create these mxArray pointers by using the mxCreateString(const char *str) function.

Before your program terminates, you must deallocate all of your mxArray pointers using the mxDestroyArray(mxArray *pm) function, and then set the pointers to NULL.

Here is an example of the typical lifecycle of an mxArray string parameter:

// Declare the pointer variable
mxArray *inputFile = NULL;

// Initialize the mxArray with a string
inputFile = mxCreateString("C:\\Program Files\\Imatest\\v4.5\\IT\\samples\\images\\sfr_example.jpg");

// Make calls to Imatest IT library

// ...

// Destroy the mxArray
mxDestroyArray(inputFile);
inputFile = NULL;   

The varargin parameter is a Matlab Cell Array containing zero or more additional input parameters, depending on the op mode. To initialize this parameter, use the mxCreateCellMatrix(int rows, int columns) function. You should create the varargin cell array with the exact number of cells required for your op mode. The rows parameter should always be 1, and the columns parameter should be the number of parameters you will be supplying.

You can then set the individual cells using mxSetCell(mxArray *array, int index, mxArray *value), where array is the varargin pointer, index is a zero-based index, and value is an mxArray pointer to the value being added to the array.

The varargin parameter is deallocated in the same way as other mxArrays, and you should not deallocate the individual cells of the array.

mxArray *varargin = NULL, *iniFile = NULL, *inputFile2 = NULL;

iniFile = mxCreateString("C:\\Program Files\\Imatest\\v4.5\\IT\\samples\\cpp\\Imatest_INI\\imatest-v2.ini");
inputFile2 = mxCreateString("C:\\Program Files\\Imatest\\v4.5\\IT\\samples\\images\\sfr_example.jpg");

varargin = mxCreateCellMatrix(1, 2);

mxSetCell(varargin, 0, iniFile);
mxSetCell(varargin, 1, inputFile2);   

// ...

mxDestroyArray(varargin);

Calling Imatest IT Modules

Now that the library is initialized, and all of the input parameters are set up, it is time to call the Imatest IT analysis function. This example uses the SFR module, but the same code can be used to call the rest of the Imatest modules (with the exception of OIS, which has different inputs).

The first parameter will always be 1, and the second is a reference to an mxArray* pointer that will contain the JSON output of the analysis. If the function returns false, it means an error has occurred. Check the stdout and stderr streams for details on what went wrong, and see the section Error Handling below for information on handling errors gracefully.

When the call is successful, the JSON output will reside inside the outputJSON pointer. You can extract the string using the mxArrayToString(const mxArray *array_ptr) function.

if (!mlfSfr_shell(1, &outputJSON, inputFile, rootDir, inputKeys, opMode, varargin))
{
    printf("*** Error calling SFR.  Check output messages for details. ***\n");
}
else
{
    jsonOutput = mxArrayToString(outputJSON);
    printf(jsonOutput);
}

When you are finished making calls to the Imatest IT C library, you then need to make three more function calls to terminate the library and the Matlab MCR.

mlfIt_terminate();
imatest_libraryTerminate();
mclTerminateApplication();

Windows (Visual Studio) Project Setup

First, you need to configure your project to be able to find the Imatest IT and Matlab MCR libraries. To do this, right click on the project and choose Properties. Add the following include directories in the sections under Configuration Properties:

Category Property Value
C/C++ / General Additional Include Directories C:\Program Files\MATLAB\MATLAB Runtime\v901\extern\include
C:\Program Files\Imatest\v4.5\IT\libs\library\cpp
Linker / General Additional Include Directories C:\Program Files\MATLAB\MATLAB Runtime\v901\extern\lib\win64\microsoft
C:\Program Files\Imatest\v4.5\IT\libs\library\cpp
Linker / Input Additional Dependencies mclmcrrt.lib
imatest_library.lib

Note: Imatest 4.5 and newer only supports 64-bit architectures. You must use the x64 platform configuration when using Imatest IT in your projects. You may need to manually add this platform configuration to your project first. For information on how to do this, see this article.

Initializing the Imatest IT Library

Now that your project references are set up, the next step is to include the imatest_library.h header file. Add this line to the top of your source file:

#include "imatest_library.h"

Next, initialize the Matlab MCR application state by calling mclInitializeApplication(const char **options, int count). Most users can ignore the options and count parameters; just pass in NULL and 0, respectively. The function will return 0 if successful, allowing you to trap errors and handle them gracefully.

#include "imatest_library.h"

int main()
{
    if (!mclInitializeApplication(NULL,0))
    {
        std::cerr << "Error: could not initialize the Matlab MCR properly." << std::endl;
        return -1001;
    }

    /// ...
}

The last initialization step is to call imatest_libraryInitialize(). This will prepare the Imatest IT library for use. The function also returns 0 if it is successful.

#include "imatest_library.h'

int main()
{
    if (!mclInitializeApplication(NULL,0))
    {
        std::cerr << "Error: could not initialize the Matlab MCR properly." << std::endl;
        return -1001;
    }

    if(!imatest_libraryInitialize())
    {
        std::cerr << "Error: could not initialize the Imatest IT library properly." << std::endl;
        return -1002;
    }

    /// ...
}

Calling the Imatest IT C++ Library Interface

Now that the Matlab MCR and Imatest IT library are all ready to go, the next step is the prepare the arguments that will be passed into the IT module functions. Each of the IT modules has the same method signature (with the exception of OIS). In this example, we will use the sfr function. The signature for the SFR module function looks like this:

void sfr_shell(int nargout, mwArray& nret, const mwArray& inputFile, const mwArray& rootDir, const mwArray& inputKeys, const mwArray& opMode, const mwArray& varargin);

The Imatest IT C++ library encapsulates all input and output arguments inside mwArray objects. This is a generic wrapper class that can represent any data type. See below for more information on using mwArrays.

The Imatest IT C++ library parameters are listed here:

Parameter Name Data Type Description
nargout int

The number of expected output arguments. This will always be 1 for the JSON result string.

nret mwArray& [const char*]

The output object, which will be a string wrapped in an mwArray object.

inputFile mwArray& [const char*]

Image file path. A full path name may be used (and is recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If a relative path name is used, the path is relative to your calling program, not the value of the rootDir parameter.
Multiple files can be analyzed by using a wildcard (*) symbol in the path. For example, if the inputFile parameter is “C:\Imatest\iPhone6_*.jpg”, all .jpg files in the folder C:\Imatest with filenames beginning with “iPhone6_” will be analyzed.

rootDir mwArray& [const char*]

Directory containing your INI file. If you do not pass a file path in as the first item in the varargin parameter, then Imatest IT will use a file named imatest-v2.ini found in this directory as your INI configuration.

inputKeys mwArray& [const char*]

This value should always be the string “JSON”. XML output has been deprecated.

opMode mwArray& [const char*]

String containing one of the following operation codes, which tells Imatest IT how to analyze your image(s), and how to read the values contained in the varargin parameter.

If you are supplying your own full path to an INI file, and it is the first item in the varargin collection, then use one of these values: -7, -8, -10, or -17. If your INI file is named imatest-v2.ini and resides in the directory passed in as rootDir, then use one of these values: -5, -6, -9, and -15.

The different opCode values direct how Imatest IT will behave. For more information on the different op modes supported by Imatest IT, see this article.

varargin mwArray& [multiple const char*]

This is a catch all array structure for other parameters required by the various op modes. The contents of this array depend on which op mode you are using, and on how many images you will be processing. For information on how to populate this array, see here.

Working with mwArrays

The Imatest IT C++ library receives and returns data via mwArray objects. Unlike the C library, the C++ library’s mwArray class is object-oriented, and also takes care of allocating and deallocating automatically. There is no need to manually destroy the mwArray objects.

Most of the Imatest IT C++ library input parameters (with the exception of varargin and raw image data passed in when using direct read mode) are strings (const char*) wrapped as mwArray objects. You can create these mwArray pointers by passing a const char* into the constructor.

mwArray opMode("-5");

The varargin parameter is a Matlab Cell Array containing zero or more additional input parameters, depending on the opMode. To initialize this parameter, use the mwArray(int num_rows, int num_cols, mxClassID mxID) constructor, passing 1 for num_rows, the number of extra arguments required as num_cols, and the constant mxCELL_CLASS as mxID. The num_cols value should be the exact number of cells required for your op mode. See this article for more information on populating the varargin parameter.

You can then set the individual cells using the mwArray object’s Get(int row, int column) and Set(const mwArray& arr) methods. Note that the row and column parameters are 1-based indexes.

/// Set the first cell of varargin to be the iniFilePath
varargin.Get(1,1).Set(iniFilePath);    

Calling Imatest IT Modules

Now that the library is initialized, and all of the input parameters are set up, it is time to call the Imatest IT analysis function. This example uses the SFR module, but the same code can be used to call the rest of the Imatest modules (with the exception of OIS, which has different inputs).

The first parameter will always be 1, and the second is a reference to an uninitialized mwArray variable that will contain the JSON output of the analysis. If the function throw an exception, it means an error has occurred. Check the exception messages and stdout and stderr streams for details on what went wrong. See the section on Error Handling below for more information on catching and handling exceptions gracefully.

When the call is successful, the JSON output will reside inside the outputJSON pointer. You can extract the string by calling the mwArray.ToString() method, then converting that result to a const char*. Note that you must declare the mwString variable separately for this to work.

sfr_shell(1, outputJSON, inputFile, rootDir, inputKeys, opMode, varargin)
mwString mwStr = outputJSON.ToString();
const char* strOutputJSON = (const char*)mwStr;

std::cout << strOutputJSON << std::endl;

When you are finished making calls to the Imatest IT C++ library, you then need to make three more function calls to terminate the library and the Matlab Runtime.

it_terminate();
imatest_libraryTerminate();
mclTerminateApplication();

Note: Imatest 4.5 and newer only supports 64-bit architectures. You must use the 64-bit version of Python when using Imatest IT.

Calling the Imatest IT Python Interface

At the top of your script file, include this line to import the ImatestLibrary class from the imatest.it module:

from imatest.it import ImatestLibrary

Next, create an instance of the ImatestLibrary class. Behind the scenes, the ImatestLibrary constructor will start up the Matlab MCR Runtime and load all the IT libraries into memory. This will take a few seconds the first time you run it, but should be faster on subsequent runs, especially if you have set your system’s environment variables to the recommended values as described above.

from imatest.it import ImatestLibrary

imatestLib = ImatestLibrary()

Now that the Matlab MCR and Imatest IT library are all ready to go, the next step is the prepare the arguments that will be passed into the IT module functions. Each of the IT modules has the same method signature (with the exception of OIS). In this example, we will use the sfr function. The signature for the SFR module function looks like this:

sfr(input_file=None, root_dir=None, op_mode=None, ini_file=None, raw_data=None, json_args=None)

The Imatest IT Python library parameters are listed here:

Parameter Name Data Type Description
input_file string or list

Image file path. A full path name may be used (and is recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If a relative path name is used, the path is relative to your calling program, not the value of the root_dir parameter.
Multiple files can be analyzed by passing in a list of file names, or by using a wildcard (*) symbol in the path. For example, if the input_file parameter is “C:\Imatest\iPhone6_*.jpg”, all .jpg files in the folder C:\Imatest with filenames beginning with “iPhone6_” will be analyzed.

root_dir string

Directory containing your INI file. If you do not pass a file path in as the ini_file parameter, then Imatest IT will use a file named imatest-v2.ini found in this directory as your INI configuration.

op_mode string

String containing one of the following operation codes, which tells Imatest IT how to analyze your image(s), or if you are using Direct Read mode. Valid values for the op_mode parameter are found in constants of the ImatestLibrary class: ImatestLibrary.OP_MODE_SEPARATE, ImatestLibrary.OP_MODE_SIGNAL_AVERAGE, ImatestLibrary.OP_MODE_TEMPORAL, and ImatestLibrary.OP_MODE_DIRECT_READ. For more information on the different op modes supported by Imatest IT, see this article.

ini_file string (optional)

If you want to use an INI file that is not named imatest-v2.ini, you will need to supply the path to the file as the ini_file parameter.

raw_data string (optional)

The raw image data. Only used when using OP_MODE_DIRECT_READ. For more information on direct read mode, see this article.

json_args string (optional)

A JSON string containing metadata about how to interpret the image in the raw_data parameter. Only used when using OP_MODE_DIRECT_READ. For more information on direct read mode, see this article.

Calling Imatest IT Modules

Now that the library is initialized, and all of the input parameters are set up, it is time to call the Imatest IT analysis function. This example uses the SFR module, but the same code can be used to call the rest of the Imatest modules (with the exception of OIS, which has different inputs).

It’s easiest to call the sfr using named parameters, as shown below. An exception will be thrown if something goes wrong – you should catch it and handle it gracefully. Check the exception message and stdout and stderr streams for details on what went wrong, and see the Error Handling section below for more information on gracefully handling exceptions.

When the call is successful, the function will return a string containing JSON-encoded output.

from imatest.it import ImatestLibrary
import json

imatestLib = ImatestLibrary()

result = imatestLib.sfr(input_file=input_file,
                        root_dir=root_dir,
                        op_mode=ImatestLibrary.OP_MODE_SEPARATE,
                        ini_file=ini_file)
print(result)

When you are finished making calls to the Imatest IT Python library, you then need to call terminate_library() to unload the library and the Matlab Runtime.

imatestLib.terminate_library();

Windows (Visual Studio) Project Setup

To use the Imatest IT .NET libraries in your Visual Studio project, first you need to add a reference to the library DLL in your project.

Once your project is created in Visual Studio, right click on the References section of the Solution Explorer and choose Add Reference….

In the Reference Manager window, choose Browse on the left-hand side, then click the Browse… button at the bottom.

IT_NET_Reference_Window

Navigate to the .NET library directory of your Imatest IT installation (by default, C:\Program Files\Imatest\v4.5\IT\libs\library\.NET\), choose Imatest.IT.dll, and click the Add button.

Note: You do not need to add the IT.dll reference to your project.

IT_NET_DLL_Selected

Click OK to close the Reference Manager window.

Note: Imatest 4.5 and newer only supports 64-bit architectures. You must use the x64 platform when running .NET applications. The Any CPU platform will throw runtime errors.

Calling the Imatest IT .NET Interface

At the top of your source code file, add a using statement for Imatest.IT:

using Imatest.IT;
At the top of your source code file, add an Imports statement for Imatest.IT:

Imports Imatest.IT

Next, create an instance of the Imatest.IT.Library class. Behind the scenes, the Imatest.IT.Library constructor will start up the Matlab MCR Runtime and load all the IT libraries into memory. This will take a few seconds the first time you run it, but should be faster on subsequent runs, especially if you have set your system’s environment variables to the recommended values as described above.

Imatest.IT.Library implements the IDisposable interface, and we recommend that you wrap your library instance inside of a using statement to ensure that the Dispose() method is called properly. The Dispose() method cleans up the Matlab Runtime, and also releases your floating license seat, if you are using a floating license.

using Imatest.IT;

class Program
{
    static void Main(string[] args)
    {
        using (Library itLib = new Library())
        {
            // ....
        }
    }
}

Imatest.IT.Library implements the IDisposable interface, and we recommend that you wrap your library instance inside of a Using statement to ensure that the Dispose() method is called properly. The Dispose() method cleans up the Matlab Runtime, and also releases your floating license seat, if you are using a floating license.

Imports Imatest.IT

Module Program
    Sub Main()
        Using itLib = New Library()
            ' ...
        End Using
    End Sub
End Module

Now that the Matlab MCR and Imatest IT library are all ready to go, the next step is the prepare the arguments that will be passed into the IT module functions. Each of the IT modules has the same overloaded method signatures (with the exception of OIS). In this example, we will use the SFR.JSON methods. The signatures for the SFR module function looks like this:

string SFR.JSON(string rootDir, string inputFile, OperationMode opMode)
string SFR.JSON(string rootDir, IEnumerable<string> inputFiles, OperationMode opMode)
string SFR.JSON(string rootDir, string inputFile, OperationMode opMode, string iniFilePath)
string SFR.JSON(string rootDir, IEnumerable<string> inputFiles, OperationMode opMode, string iniFilePath)
string SFR.JSON(string rootDir, byte[] inputBytes, DirectReadOptions directReadOptions)
string SFR.JSON(string rootDir, byte[] inputBytes, DirectReadOptions directReadOptions, string iniFilePath)
SFR.JSON(String rootDir, String inputFile, OperationMode opMode) As String
SFR.JSON(String rootDir, IEnumerable(Of String) inputFiles, OperationMode opMode) As String
SFR.JSON(String rootDir, String inputFile, OperationMode opMode, String iniFilePath) As String
SFR.JSON(String rootDir, IEnumerable(Of String) inputFiles, OperationMode opMode, String iniFilePath) As String
SFR.JSON(String rootDir, Byte() inputBytes, DirectReadOptions directReadOptions) As String
SFR.JSON(String rootDir, Byte() inputBytes, DirectReadOptions directReadOptions, String iniFilePath) As String

The Imatest IT .NET library parameters are listed here:

Parameter Name Data Type Description
rootDir string

Directory containing your default INI file. If you do not pass a file path in as optional the iniFile parameter, then Imatest IT will use a file named imatest-v2.ini found in this directory as your INI configuration.

inputFile string

Image file path. A full path name may be used (and is recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If a relative path name is used, the path is relative to your calling program, not the value of the rootDir parameter.
Multiple files can be analyzed by using a wildcard (*) symbol in the path. For example, if the input_file parameter is “C:\Imatest\iPhone6_*.jpg”, all .jpg files in the folder C:\Imatest with filenames beginning with “iPhone6_” will be analyzed.

inputFiles IEnumerable<string>

A list of image file paths. Full path names may be used (and are recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If relative path names are used, the path is relative to your calling program, not the value of the rootDir parameter.

opMode OperationMode

Enum value for one of the available operation modes, which tells Imatest IT how to analyze your image(s). Valid values for the opMode parameter are: OperationMode.Separate, OperationMode.SignalAverage, and OperationMode.Temporal. For more information on the different op modes supported by Imatest IT, see this article.

iniFile string (optional)

If you want to use an INI file that is not named imatest-v2.ini, you will need to supply the path to the file as the iniFile parameter.

inputBytes byte[], ushort[], or uint[] (optional)

The raw image data. Only used if you are passing in image data directly using Direct Read Mode. For more information on direct read mode, see this article.

directReadOptions DirectReadOptions (optional)

A an object containing metadata about how to interpret the image in the inputBytes parameter. Only used when using Direct Read Mode. For more information on direct read mode, see this article.

Parameter Name Data Type Description
rootDir String

Directory containing your default INI file. If you do not pass a file path in as optional the iniFile parameter, then Imatest IT will use a file named imatest-v2.ini found in this directory as your INI configuration.

inputFile String

Image file path. A full path name may be used (and is recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If a relative path name is used, the path is relative to your calling program, not the value of the rootDir parameter.
Multiple files can be analyzed by using a wildcard (*) symbol in the path. For example, if the input_file parameter is “C:\Imatest\iPhone6_*.jpg”, all .jpg files in the folder C:\Imatest with filenames beginning with “iPhone6_” will be analyzed.

inputFiles IEnumerable(Of String)

A list of image file paths. Full path names may be used (and are recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If relative path names are used, the path is relative to your calling program, not the value of the rootDir parameter.

opMode OperationMode

Enum value for one of the following operation codes, which tells Imatest IT how to analyze your image(s). Valid values for the opMode parameter are: OperationMode.Separate, OperationMode.SignalAverage, and OperationMode.Temporal. For more information on the different op modes supported by Imatest IT, see this article.

iniFile String (optional)

If you want to use an INI file that is not named imatest-v2.ini, you will need to supply the path to the file as the iniFile parameter.

inputBytes Byte(), UShort(), or UInteger() (optional)

The raw image data. Only used if you are passing in image data directly using Direct Read Mode. For more information on direct read mode, see this article.

directReadOptions DirectReadOptions (optional)

A an object containing metadata about how to interpret the image in the inputBytes parameter. Only used when using Direct Read Mode. For more information on direct read mode, see this article.

Calling Imatest IT Modules

Now that the library is initialized, and all of the input parameters are set up, it is time to call the Imatest IT analysis function. This example uses the SFR module, but the same code can be used to call the rest of the Imatest modules (with the exception of OIS, which has different inputs).

We recommend always wrapping your Imatest IT calls in try/catch blocks. If anything goes wrong, an Exception will be thrown. You should handle these exceptions gracefully. Check the exception message for details on what went wrong, and see the section on Error Handling below for more information.

When the call is successful, the function will return a string containing JSON-encoded output.

using Imatest.IT;

class Program
{
    static void Main(string[] args)
    {
        using (Library itLib = new Library())
        {
            try {
                string result = itLib.SFR.JSON(rootDir, inputFile, OperationMode.Separate, iniFilePath);
            } catch (Exception ex) {
                Console.Out.WriteLine(ex.Message);
            }
        }
    }
}
Imports Imatest.IT

Module Program
    Sub Main()
        Using itLib = New Library()
            Try
                Dim result = itLib.SFR.JSON(rootDir, imagePath, OperationMode.Separate, iniFilePath)
            Catch ex As Exception
                Console.Out.WriteLine(ex.Message)
            End Try
        End Using
    End Sub
End Module

Calling the Imatest IT EXE Interface

The Imatest IT EXE Library can be called using Windows or Linux script files. We recommend making sure that the IT bin directory is in your PATH variable. On Windows, this should already happen when Imatest IT is installed. You may need to add to your path manually on Linux. For more information on viewing and editing system environment variables, see this article.

All Imatest IT EXE executables accept the following arguments (except for OIS, which uses different inputs):

sfr.exe op-mode input-file bin-directory ini-file [result-directory] [other-images ...]

The Imatest IT EXE library parameters are listed here:

Parameter Name Description
op_mode

One of the following operation codes, which tells Imatest IT how to analyze your image(s). Valid values for the op_mode parameter are: -1 (Separate Analysis), -11 (Signal Average Analysis), and -12 (Temporal Noise Analysis). For more information on the different op modes supported by Imatest IT, see this article.

input-file

Image file path. A full path name may be used (and is recommended), such as “C:\Program Files\Imatest\v4.5\IT\samples\images\sfr_example.jpg”. If a relative path name is used, the path is relative to your calling program.
Multiple files can be analyzed by using a wildcard (*) symbol in the path. For example, if the input_file parameter is “C:\Imatest\iPhone6_*.jpg”, all .jpg files in the folder C:\Imatest with filenames beginning with “iPhone6_” will be analyzed.

bin-directory

The location of the Imatest IT bin directory. By default, this will be “C:\Program Files\Imatest\v4.5\IT\bin” on Windows, and “/usr/local/Imatest/v4.5/IT/bin” on Linux.

ini-file

The full path to the INI configuration file you will be using.

result-directory

The directory where Imatest IT’s output files will be written to.

other-images

The path(s) to other images that will be analyzed besides the initial input-file image.

Calling Imatest IT Modules

Imatest IT EXE modules are called using the command line, or in .bat files.

Note: You should not include a trailing ‘\’ when passing in directory names, otherwise you may get an error (see here).

sfr.exe "-1" "C:\ImatestSamples\sfr_example.jpg" "C:\Program Files\Imatest\v4.5\IT\bin" "C:\ImatestSamples\imatest-v2.ini" "C:\ImatestSamples\Results"

When the module is finished running, the result files will be written to the result-directory folder (in this case, C:\ImatestSamples\Results).

Step 4: Process the Results

The Imatest IT module functions output their results as JSON, XML, and CSV formatted text files. The C, C++, Python, and .NET libraries also return results as a JSON formatted string to the calling program.

Using the JSON Result in Code

Imatest IT’s JSON result string, which is returned to the calling program, can be parsed and processed using third party JSON libraries. A list of JSON libraries for several languages can be found at json.org.

The result strings are packaged as nested property/value objects, and the first property is always [module]Results, as seen in this excerpt from an SFRplus call:

{
    "sfrplusResults": {
        "version": "Imatest 4.5.14  SFRplus",
        "title": "sfrplus_example.jpg",
        "number_of_regions": [5],
        "HeightPxls": [2592],
        "WidthPxls": [3888],
        "pixels_per_inch": [0],
        "pixels_per_mm": [0],
        "um_per_pixel": [0],
        "CPIQ": {
            "sfrComputerMonitor": {
                "acutance": [0.8444,0.8406,0.7965,0.8583,0.8579],
                "qualityLoss": [0.1755,0.2173,0.9715,0.06028,0.06267]
            },
            "sfrPhoneDisplay": {
                "acutance": [0.8785,0.8747,0.8268,0.8938,0.8935],
                "qualityLoss": [-0.005023,-0.00252,0.4007,0.00336,0.00336]
                    },
            "sfrUHDTVDisplay": {
                "acutance": [0.8287,0.8253,0.7708,0.8466,0.8463],
                "qualityLoss": [0.3724,0.4224,1.621,0.1535,0.1569]
            },
            "sfrSmallPrint": {
                "acutance": [0.6816,0.6807,0.6678,0.6852,0.6859],
                "qualityLoss": [4.755,4.791,5.328,4.606,4.577]
            },
            "sfrLargePrint": {
                "acutance": [0.8654,0.8671,0.8646,0.8658,0.8672],
                "qualityLoss": [0.02288,0.01626,0.02633,0.02126,0.01574]
            }
        },
        "mtfPeak": [1.023,1.007,1,1.045,1.036],
        "mtf50": [0.3389,0.3426,0.3089,0.3512,0.3523],
        "mtf50p": [0.3365,0.3419,0.3089,0.3461,0.3482],

        ...
    }
}

Note: If you analyze multiple files in a single call, only the last file’s results will be returned to the calling program. The others will be written to output files in the Results directory.

If you find that a result you need is missing from the returned JSON, please contact us and we can add it in the next minor release of Imatest IT.

Imatest IT Output Files

Imatest IT also writes its results to text files, which are formatted in XML, CSV, and JSON. By default, these files are written to a Results folder in the same folder as the images themselves. You can change the location by using Imatest Master or Image Sensor to change your INI configuration settings, in the Auto mode settings for the modules you will be using:

Performance Tip: If you do not need some or all of the output files, you can disable them using the same Auto mode settings window. This will make your Imatest IT calls run a little faster. Just uncheck each of the outputs that you do not require.

Error Handling

Select your preferred interface below to see the best ways to handle errors using Imatest IT.

Interface Type:

In the Imatest C library, if an error occurs within one of the analysis module functions, a false result will be returned. You can then use the mlfGetExceptionID(int nargout, mxArray** errID, mxArray** errName) function to extract an Error ID and Error Name, which map into the Imatest IT Exception Hierarchy.

To make handling these exceptions easier, Imatest IT includes an optional header file, imatest_exception_IDs.h, which maps each of the Error IDs to an enum. To include this header file, add #include “imatest_exception_ids.h” to your source file. You can read more about the Exception Hierarchy here.

Here is an example of how you can catch and gracefully handle exceptions using the Imatest IT C Library:

int retVal;
mxArray *errorID = NULL, *errorName = NULL;
enum ImatestExceptionIDs errorCode;
const char* errorNameStr;

...

if (!mlfSfr_shell(nargout, &amp;outputJSON, inputFile, rootDir, inputKeys, opMode, varargin))
{
    if (mlfGetExceptionID(2, &amp;errorID, &amp;errorName))
    {
        errorCode = (enum ImatestExceptionIDs)mxGetScalar(errorID);
        printf("*** Error ID: %d\n", errorCode);
     
        switch (errorCode)
        {
            case kImatestFileNotFoundException:
                printf("File not found exception.\n");
                break;
            case kBadFramingException:
                printf("Bad framing exception.\n");
                break;
            default:
                errorNameStr = mxArrayToString(mxGetCell(errorName, 0));
                printf("*** Unexpected Error: %s\n", errorNameStr);
                break;
        }

        mxDestroyArray(errorID);
        mxDestroyArray(errorName);
        retVal = errorCode;
    }
    else {
        printf("*** Unknown Error.\n");
        retVal = -1005;
    }
}
else
{
   retVal = 0;
   ...
}

In the Imatest C++ library, if an error occurs within one of the analysis module functions, an mwException will be thrown. If you catch the exception, then you can use the getExceptionID(int nargout, mwArray& errID, mwArray& errName) function to extract an Error ID and Error Name, which map into the Imatest IT Exception Hierarchy.

To make handling these exceptions easier, Imatest IT includes an optional header file, imatest_exception_IDs.h, which maps each of the Error IDs to an enum. To include this header file, add #include “imatest_exception_ids.h” to your source file. You can read more about the Exception Hierarchy here.

Here is an example of how you can catch and gracefully handle exceptions using the Imatest IT C++ Library:

try 
{
    sfr_shell(1, outputJSON, inputFile, rootDir, inputKeys, opMode, varargin)
} 
catch (const mwException&amp;  e)
{
    mwArray mwErrorID, mwErrorName;
    mwString mwErrorNameStr;
    getExceptionID(2, mwErrorID, mwErrorName);
    int err = (int)mwErrorID;

    switch (err)
    {
        case imatest::kImatestFileNotFoundException:
            std::cerr &lt;&lt; "*** File was not found. Check the file path." &lt;&lt; std::endl;
            break;
        case imatest::kBadFramingException:
            std::cerr &lt;&lt; "*** Image is not framed correctly." &lt;&lt; std::endl;
            break;
        default:
            mwErrorNameStr = mwErrorName.Get(1,1).ToString();
            std::cerr &lt;&lt; "*** Unexpected Error: " &lt;&lt; mwErrorNameStr &lt;&lt; std::endl;
            break;
    }

    retVal = err;
}

In the Imatest Python library, if an error occurs within one of the analysis module functions, an ImatestException will be thrown. If you catch the exception, then you can get more information about using the error_id, error_name, and message properties.

Here is an example of how you can catch and gracefully handle exceptions using the Imatest IT Python Library. You can use the constants on the ImatestException class to handle certain error types in different ways. In this example, an ImatestException will be thrown because all floating license seats are currently being used:

from imatest.it import ImatestLibrary, ImatestException
...
try:
    result = imatestLib.sfr(input_file=input_file,
                            root_dir=root_dir,
                            op_mode=ImatestLibrary.OP_MODE_SEPARATE,
                            ini_file=ini_file)
except ImatestException as ex:
    if iex.error_id == ImatestException.FloatingLicenseException:
        print("All floating license seats are in use.  Exit Imatest on another computer and try again.")
    elif iex.error_id == ImatestException.LicenseException:
        print("License Exception: " + iex.message)
    else:
        print("*** Error calling sfr: %s" % (iex.message, ))

In the Imatest .NET library, if an error occurs within one of the analysis module functions, an Exception will be thrown. If you catch the exception, then you can get more information about it by calling the ImatestLibrary.GetLastException() and ImatestLibrary.GetExceptionName() methods.

Here is an example of how you can catch and gracefully handle exceptions using the Imatest IT .NET Library:

try
{
    string result = itLib.SFRplus.JSON(rootDir, imagePath, OperationMode.Separate, iniFile);
}
catch (Exception ex)
{
    ImatestException iex = lib.GetLastException();
    string errorName = lib.GetExceptionName();
    if (iex == ImatestException.FloatingLicenseException)
    {
        Console.Out.WriteLine("All floating license seats are in use.  Exit Imatest on another computer and try again.");
    }
    else if (iex == ImatestException.LicenseException)
    {
        Console.Out.WriteLine("License Exception: {0}: {1}", errorName, ex.Message);
    }
    else
    {
        Console.Out.WriteLine("An error has occurred:");
        Console.Out.WriteLine(ex.Message);
    }
}
Try
    Dim result = itLib.SFR.JSON(rootDir, imagePath, OperationMode.Separate, iniFile)
Catch ex As Exception
    Dim iex As ImatestException = library.GetLastException()
    Dim errorName As String = library.GetExceptionName()
    If iex = ImatestException.FloatingLicenseException Then
        Console.Out.WriteLine("All floating license seats are in use.  Exit Imatest on another computer and try again.")
    ElseIf iex = ImatestException.LicenseException Then
        Console.Out.WriteLine("License Exception: {0}: {1}", errorName, ex.Message)
    Else
        Console.Out.WriteLine("An error has occurred:")
        Console.Out.WriteLine(ex.Message)
    End If
End Try

In the Imatest EXE library, if an error occurs within one of the analysis module functions, the return code from the executable will be -1 instead of 0. If you are calling the executable from a batch script, you can check what the return code was to determine if an exception occurred or not.

Here is an example of how you can test for an exception using the Imatest IT EXE Library:

sfr.exe "-1" "'C:\ImatestSamples\sfr_example.jpg'" "'C:\Program Files\Imatest\v4.5\IT\bin'" "'C:\ImatestSamples\imatest-v2.ini'" "'C:\ImatestSamples\Results'"
if %ERRORLEVEL% neq 0 (
    echo '*** Error calling sfr. Check output for details.'
)

Sample Code

Imatest IT ships with several example projects in C++, Python, C#, and Visual Basic. You can find them in the samples folder of your IT installation, along with example images of Imatest test charts that can be used for each of IT’s analysis modules.

Imatest IT for Windows also comes with a sample GUI application that demonstrates integrating the IT .NET libraries in a full-featured GUI application. Using the example images provided in the samples folder, you can experiment with the different analysis modules. It also provides a simple way to interact with the Imatest Acquisition Library. Using this app, you can quickly connect and test any of the supported image capture devices and make sure they are working, without writing any code. The full source code for this app is included in the .NET C# samples folder.

Advanced Topics

Direct Read Mode and Reading RAW Images

Images can be passed directly into Imatest IT as byte arrays using Direct Read Mode. The images can be processed RGB or RAW. Direct Read Mode is generally much faster than passing in image file paths, since the data is already in memory and does not need to be read from disk. Although it does require more initial setup effort, if your application is speed-critical or high-volume, we strongly recommend using Direct Read Mode.

For detailed instructions on using Imatest IT’s Direct Read Mode, see this article.

Using the Imatest Image Acquisition Library

Images can be directly acquired in your application from supported devices using the Imatest IT Acquisition Library (C, C++, and .NET only).

For more information on the C and C++ version of the Acquisition Library, see this article. For the .NET version, see this article.

Using Pass/Fail Metrics

Pass/Fail results are included in the JSON results for those modules that support it (Blemish, Colorcheck, Distortion, Multitest, SFR, SFRplus, Random, Star, Stepchart, and Uniformity). If you have configured Pass/Fail criteria, and included the Pass/Fail file in your INI file, then the tests will be run, and the results will be included as a separate JSON object called “passfail”.

For more information on implementing Pass/Fail in Imatest, see this article.

Redirecting Output

By default, the Imatest IT modules print some information to the standard output or console. If your application does not have a console, or you want to store this output in another way, it is possible to redirect the standard out and standard error outputs.

Select your preferred interface below to see detailed instructions.

Interface Type:
To redirect output text using the Imatest C or C++ libraries, you need to use the function imatest_libraryInitializeWithHandlers(mclOutputHandlerFcn error_handler, mclOutputHandlerFcn print_handler) instead of imatest_libraryInitialize(), passing in two pointers to functions that will handle the “error” and “standard” outputs, respectively. The functions accept a const char* input, and return an int, which is the number of characters processed.

int stdOutHandler(const char* str)
{
    // Record output
    ... 
    return strlen(str);
}

int stdErrHandler(const char* str)
{
    // Record output
    ... 
    return strlen(str);
}

if (!imatest_libraryInitializeWithHandlers(stdErrHandler, stdOutHandler))
{
   ...
To redirect output text using the Imatest Python library, you need to pass in StringIO objects to the ImatestLibrary() constructor, as the stdout and stderr named parameters. You can extract the contents of these objects using the getvalue() method, and should call close() on them at the end of your script.

import StringIO

std_out = StringIO.StringIO()
std_err = StringIO.StringIO()

libImatest = ImatestLibrary(stdout=out_file, stderr=err_file)
# Call library methods …
print std_out.getvalue()
print std_err.getvalue()
std_out.close()
std_err.close()
To redirect output text using the Imatest .NET library, you need to use the Console.SetOut(TextWriter writer) and Console.SetError(TextWriter writer) methods. You must call these methods before creating the Imatest.IT.Library object.
StringWriter stdOut = new StringWriter();
StringWriter stdErr = new StringWriter();
Console.SetOut(stdOut);
Console.SetError(stdErr);

...

string stdOutText = stdOut.ToString();
string stdErrText = stdErr.ToString();
stdOut.Close();
stdErr.Close();
Dim stdOut As New StringWriter()
Dim stdErr As New StringWriter()

Console.SetOut(stdout)
Console.SetError(stderr)

...

Dim stdOutStr As String = stdOut.ToString()
Dim stdErrStr As String = stdErr.ToString()
stdOut.Close()
stdErr.Close()
To redirect output using the Imatest IT EXE interface, use the typical command line syntax you normally would use.

Advanced: Asynchronous Programming with Imatest IT .NET

With the Imatest IT .NET library, you can easily use write asynchronous module calls in your custom applications using the .NET Framework’s async and await keywords along with Imatest IT .NET’s JSONAsync() methods.

Making these simple changes can have dramatic effect on the responsiveness of applications, especially if they are GUI-based. To see the difference in action, run the Imatest IT .NET Sample Application found at C:\Program Files\Imatest\v4.5\IT\samples\.NET\ImatestITSampleProject\ImatestITSampleProject.exe and try both the Run and Run Async buttons. You will notice the application appears to freeze when using the non-async version, but is fully responsive when using the async methods.

Altering Existing Imatest IT .NET Code to be Asynchronous

There are only three changes that need to be made to convert single-threaded code into asynchronous code.:

  • Add an async modifier to the signature in which the asynchronous code will be called.
  • Add the await in front of the Imatest IT method call.
  • Change the Imatest IT method call to use the new Async version.

Below is a code snippet of synchronous code making a simple call to the SFRPlus module:

protected void TestImage()
{
    using (Library lib = new Library())
    {
        string rootDir = @"C:\ImatestSamples\";
        string imagePath = @"C:\ImatestSamples\sfrplus_example.jpg";

        // Call Imatest IT library with JSON output
        string result = lib.SFRplus.JSON(rootDir, imagePath, OperationMode.Separate);

        Console.Out.WriteLine(result);
    }
}

Below is the same code that has been converted to call the SFRplus module asynchronously:

protected async void TestImage()
{
    using (Library lib = new Library())
    {
        string rootDir = @"C:\ImatestSamples\";
        string imagePath = @"C:\ImatestSamples\sfrplus_example.jpg";

        // Call Imatest IT library with JSON output
        string result = await lib.SFRplus.JSONAsync(rootDir, imagePath, OperationMode.Separate);

        // Continue other operations that do not rely on the result value of the test
        
        Console.Out.WriteLine(result);
    }
}

Initializing the Imatest IT .NET Libraries Asynchronously

The Imatest IT .NET and Imatest Acquisition Library classes have static CreateAsync() methods that can be called using the await keyword:

public async void InitializeApplication()
{
    /// Inside application initialization code
    
    /// The await keyword will automatically start a new thread to initialize the library, 
    /// while code in the main thread continues to execute until the itLib object is 
    /// actually used.
    Library itLib = await Library.CreateAsync();
    
    /// Continue initializing the rest of the application while the background thread
    /// initializes the rest of the application
    
    ...
    
    /// The main thread will wait here until the secondary thread is completed and the 
    /// Library.CreateAsync() method has returned a Library object.
    await itLib.SFRplus.JSONAsync(rootDir, inputFile, OperationMode.Separate); 
    
    /// At this point only the main thread is running
}

Parallel Processing

Starting with version 5.0, Imatest IT now allows you to analyze several different images in parallel,
using the new parallel_analyzer function.

Interface Type:
Coming soon…

To use the parallel_analyzer, first create a list of analysis tasks that need to be run. Each task will be assigned to a different parallel process. The number of available concurrent processes depends on how many cores your machine has, though you can tell Imatest IT to use fewer cores if you need.

The parallel_analyzer_shell() C++ interface

The signature of the parallel_analyzer_shell() function is as follows:

parallel_analyzer_shell(int nargout, mwArray&amp; results, const mwArray&amp; tasks, const mwArray&amp;  iniFileName, const mwArray&amp; runParallel, const mwArray&amp; numWorkers);

 

Parameter Name Data Type Description
nargout int The number of expected output arguments. This will be set to 1.
results mwArray& [const char*] The serialized JSON object array wrapped in a mwArray
tasks const mwArray& [mxSTRUCT_CLASS] The array of analysis tasks to run. For further information see below.
iniFileName const mwArray& [const char*] The path for the Imatest INI file used for analysis
runParallel const mwArray& [bool] A boolean set to true if parallel analysis is desired, otherwise set to false for serial operation.
numWorkers const mwArray& [int] The number of child processes to spawn.

 

The tasks array is a mwArray of ClassID mxSTRUCT_CLASS. This data type has named fields, as with C++ structs. Each element of the task array has these fields:

input – The supplied image in the form of file path(s) or numeric array(s)
analysisID – An integer that tells IT which module to run. The allowed values are defined in the ImatestAnalysisIDs enum (see <IT installation root>\libs\library\cpp\Imatest_analysis_ids.h):
imatest::BLEMISH_ANALYSIS_ID
imatest::CHECKERBOARD_ANALYSIS_ID
imatest::COLORCHECK_ANALYSIS_ID
imatest::DISTORTION_ANALYSIS_ID
imatest::DOTPATTERN_ANALYSIS_ID
imatest::ESFRISO_ANALYSIS_ID
imatest::MULTITEST_ANALYSIS_ID
imatest::RANDOM_ANALYSIS_ID
imatest::SFR_ANALYSIS_ID
imatest::SFRPLUS_ANALYSIS_ID
imatest::SFRREG_ANALYSIS_ID
imatest::STAR_ANALYSIS_ID
imatest::UNIFORMITY_ANALYSIS_ID
imatest::WEDGE_ANALYSIS_ID
jsonMetaData – Image meta data in the form of serialized JSON object string. This field only needs to be filled when numeric arrays are being supplied.

An example of the creation of the tasks array for four image files is available in the parallel_analyzer sample project (<IT installation root>\samples\cpp\parallel_analyzer\main.cpp). In this example, the tasks array is created with

 mwSize numRows = 4; // There are 4 images to test
 mwSize numCols = 1;
 int numFields = 3;
 const char* fieldNames[] = {"input\0", "analysisID\0", "jsonMetadata\0"};

 mwArray tasks(numRows, numCols, numFields, fieldNames);

To supply values to the individual tasks, we make use of the Get(const char* fieldName, int numIndices, int index1, …) accessor for mxSTRUCT_CLASS mwArrays:

// define the first task 
tasks.Get("input", 1, 1).Set(mwArray(".\\sfrplus_example.jpg"));
tasks.Get("analysisID", 1, 1).Set(sfrplusID);

// define the second task
tasks.Get("input", 1, 2).Set(mwArray(".\\blemish_example.jpg"));
tasks.Get("analysisID", 1, 2).Set(blemishID);

//define the third task
tasks.Get("input", 1, 3).Set(mwArray(".\\colorcheck_example.jpg"));
tasks.Get("analysisID", 1, 3).Set(colorcheckID);

//define the fourth task
tasks.Get("input", 1, 4).Set(mwArray(".\\esfriso_example.jpg"));
tasks.Get("analysisID", 1, 4).Set(esfrisoID);

It is important to note that this array is 1-indexed.

Creation of the remaining inputs is simpler; we use the mwArray contructors for scalar numeric values and strings.

mwArray iniFileName("..\\Imatest_INI\\imatest-v2.ini");

mwArray runParallel(true);

mwArray numWorkers(2);

Lastly, we call parallel_analyzer_shell() with the inputs.

mwArray out;
parallel_analyzer_shell(1, out, tasks, iniFileName, runParallel, numWorkers); 

The results will be returned in the out mwArray, which contains a JSON encoded string that can be parsed into an object array with one result object per task. Each result object has this form:

{
   "data": {
      "dateRun": "18-Sep-2017 10:26:59",
      "ini_file_name": "C:\\images\\ini_file\\imatest-v2.ini",
      "ini_time_size": "18-Sep-2017 10:26:45 21822B  MD5 = ac109f86b635bd5b4344d252969e64a7",
      "version": "Imatest 5.0.0  SFRplus",
      "title": "sfrplus_0123.jpg",
      "image_path_name": "C:\\images\\sfrplus_0123.jpg",
      
      ...
   },
   "errorID": "",
   "errorMessage": "",
   "errorReport": ""
}

If any exceptions occurred during processing, they will be reported in the errorID, errorMessage, and errorReport properties. While handling your results, you should always check whether the errorID property is empty or not before working with the data property.

 

In addition to the parallel_analyzer sample, IT also includes a C++ sample project that implements parallel processing using the Boost.Interprocess Library (<IT installation root>\samples\cpp\CPP_parallel_test_project). More information can be found in this article.

 

To use the parallel_analyzer, first create a list of analysis tasks that need to be run. Each task will be assigned to a different parallel process. The number of available concurrent processes depends on how many cores your machine has, though you can tell Imatest IT to use fewer cores if you need.

The task file

In the stand-alone executable version of parallel_analyzer, the list of tasks is supplied in the form of a JSON encoded file. In this JSON file, the list of tasks is represented by a JSON object array, where each individual task is an object within that array. For each task the following fields need to be defined:

input – The supplied image in the form of file path(s) or numeric array(s)
analysisID – An integer that tells IT which module to run. The allowed values are defined below:

Module Value
Blemish 1
Checkerboard 2
Colorcheck 3
Distortion 4
Dotpattern 5
eSFRiso 6
Multitest 7
Random 8
SFR 9
SFRplus 10
SFRreg 11
Star 12
Uniformity 13
Wedge 14

 jsonMetaData – Image meta data in the form of serialized JSON object. This field only needs to be filled when numeric arrays are being supplied.

As an example, suppose that there are two files named blemish_example.jpg and sfrplus_example.jpg in the current working directory that need to be analyzed by the Blemish and SFRplus modules, respectively. The contents of this tasks file is then

[
    {
        "input": "blemish_example.jpg",
        "analysisID": 1,
        "jsonMetadata": ""
    },
    {
        "input": "sfrplus_example.jpg",
        "analysisID": 10,
        "jsonMetadata": ""
    }
]

The parallel_analyzer_exe interface 

The signature of the parallel_analyze executable is as follows:

parallel_analyzer_exe taskFileName iniFileName runParallel numWorkers [-o|--output_filename &lt;filename&gt;]

The required inputs are
taskFileName: The path to the JSON task file (see the Task File section below).

iniFileName: The path to the Imatest INI file

runParallel: A boolean value that is 1 if the user wants parallel processing and 0 if serial processing is desired.

numWorkers: An integer value indicating the number of child processes to invoke for analysis. The maximum value is the number of physical cores.

with remaining optional input
-o|–output_filename <filename>: Supply the full file path for the file into which the results are saved. Note that either ‘-o’ or ‘–output_filename’ can be used. If this optional input is not supplied, the results are saved to a file named ‘results_<current date and time>.json’.

Continuing the above example, suppose that the task file (tasks.json) from above is in our Documents folder with the two image files and our INI file (imatest-v2.ini). The call to run the two tasks in parallel on two processes would be

cd %HOMEPATH%\Documents
C:\Program Files\Imatest\v5.0\IT\bin\parallel_analyzer_exe.exe tasks.json imatest-v2.ini 1 2

< and on Linux the command would be

cd ~/Documents
/usr/local/Imatest/v5.0.0/IT/bin/parallel_analyzer_exe ./tasks.json ./imatest-v2.ini 1 2

The results will be saved to a JSON encoded file in the form of a JSON object array with one result object per task. Each result object has this form:

{
   "data": {
      "dateRun": "18-Sep-2017 10:26:59",
      "ini_file_name": "C:\\images\\ini_file\\imatest-v2.ini",
      "ini_time_size": "18-Sep-2017 10:26:45 21822B  MD5 = ac109f86b635bd5b4344d252969e64a7",
      "version": "Imatest 5.0.0  SFRplus",
      "title": "sfrplus_0123.jpg",
      "image_path_name": "C:\\images\\sfrplus_0123.jpg",
      
      ...
   },
   "errorID": "",
   "errorMessage": "",
   "errorReport": ""
}

If any exceptions occurred during processing, they will be reported in the errorIDerrorMessage, and errorReport properties. While handling your results, you should always check whether the errorID property is empty or not before working with the data property.

Starting with version 5.0, Imatest IT now allows you to analyze several different images in parallel, using the new parallel_analyzer function.

To use the parallel_analyzer, first create a list of analysis tasks that need to be run. Each task will be assigned to a different parallel process. The number of available concurrent processes depends on how many cores your machine has, though you can tell Imatest IT to use fewer cores if you need.

To create an analysis task, use the new_parallel_task function:

ImatestLibrary.new_parallel_task(image_files=None, image_data=None, analysis_type=None, image_data_meta_data=None)
Parameter Name Data Type Description
image_files str or list of strs Either a file path to an image, or a list of file paths
image_data str/bytes or array.array (numerical) If you are providing raw image data, use this argument, which is either the read value of the image in str (Python 2.7, 3.3, 3.4) or bytes (Python 3.5) form. If using image_data, you must include the image_data_meta_data argument, which you can get by calling ImatestLibrary.build_json_args()
analysis_type enum A flag telling Imatest IT which module to run. Valid values are constants on the ImatestLibrary class:
ImatestLibrary.BLEMISH_ANALYSIS
ImatestLibrary.CHECKERBOARD_ANALYSIS
ImatestLibrary.COLORCHECK_ANALYSIS
ImatestLibrary.DISTORTION_ANALYSIS
ImatestLibrary.DOTPATTERN_ANALYSIS
ImatestLibrary.ESFRISO_ANALYSIS
ImatestLibrary.MULTITEST_ANALYSIS
ImatestLibrary.RANDOM_ANALYSIS
ImatestLibrary.SFR_ANALYSIS
ImatestLibrary.SFRPLUS_ANALYSIS
ImatestLibrary.SFRREG_ANALYSIS
ImatestLibrary.STAR_ANALYSIS
ImatestLibrary.UNIFORMITY_ANALYSIS
ImatestLibrary.WEDGE_ANALYSIS
image_data_meta_data dict A dict object containing the direct read meta data, used to help interpret the raw byte data, and obtained by calling ImatestLibrary.build_json_args(). Required if using the image_data argument, not needed if using image_files.

add each of your tasks to a list, then call ImatestLibrary.parallel_analyser, passing in the path to your INI file, True for run_parallel, and the number of worker processes you’d like to use:

ini_file = r'C:\images\ini_file\imatest-v2.ini'

tasks = []
tasks.append(library.new_parallel_task(image_files=r'C:\images\sfrplus_0123.jpg', analysis_type=ImatestLibrary.SFRPLUS_ANALYSIS))
tasks.append(library.new_parallel_task(image_files=[r'C:\images\blemish_0001.jpg', r'C:\images\blemish_0002.jpg', r'C:\images\blemish_0003.jpg'], analysis_type=ImageLibrary.BLEMISH_ANALYSIS))
....

result = library.parallel_analyzer(tasks=tasks, ini_file=ini_file, run_parallel=True, num_workers=4)

The result will be a JSON encoded string that can be parsed into an array of result objects using json.loads(result). Each result object has this form:

{
   "data": {
      "dateRun": "18-Sep-2017 10:26:59",
      "ini_file_name": "C:\\images\\ini_file\\imatest-v2.ini",
      "ini_time_size": "18-Sep-2017 10:26:45 21822B  MD5 = ac109f86b635bd5b4344d252969e64a7",
      "version": "Imatest 5.0.0  SFRplus",
      "title": "sfrplus_0123.jpg",
      "image_path_name": "C:\\images\\sfrplus_0123.jpg",
      
      ...
   },
   "errorID": "",
   "errorMessage": "",
   "errorReport": ""
}

If any exceptions occurred during processing, they will be reported in the errorID, errorMessage, and errorReport properties. While handling your results, you should always check whether the errorID property is empty or not before working with the data property:

resultArr = json.loads(result)

for task_result in result_arr:
   if task_result['errorID']:
      # Gracefully handle the error
   else:
      result_data = task_result['data']
      # Process the results in the result_data dictionary

Starting with version 5.0, Imatest IT now allows you to analyze several different images in parallel, using the new ParallelAnalyzer.Execute() method.

To use the ParallelAnalyzer, first create a List of ImatestTasks objects that contain images to be analyzed. Each task will be assigned to a different parallel process. The number of available concurrent worker processes depends on how many cores your machine has, though you can tell Imatest IT to use fewer workers if you need.

To create an ImatestTask, use one of the overloaded ImatestTask.Create() methods:

public static ImatestTask Create(string imageFilePath, ImatestModule module);
public static ImatestTask Create(IEnumerable&lt;string&gt; imageFilePaths, ImatestModule module);
public static ImatestTask Create(byte[] imageData, ImatestModule module, DirectReadOptions imageMetaData);
public static ImatestTask Create(UInt16[] imageData, ImatestModule module, DirectReadOptions imageMetaData);
public static ImatestTask Create(UInt32[] imageData, ImatestModule module, DirectReadOptions imageMetaData);
Public Shared Function Create(imageFilePath As String, [module] As ImatestModule) As ImatestTask
Public Shared Function Create(imageFilePaths As IEnumerable(Of String), [module] As ImatestModule) As ImatestTask
Public Shared Function Create(imageData() As Byte, [module] As ImatestModule, imageMetaData As DirectReadOptions) As ImatestTask
Public Shared Function Create(imageData() As UShort, [module] As ImatestModule, imageMetaData As DirectReadOptions) As ImatestTask
Public Shared Function Create(imageData() As UInteger, [module] As ImatestModule, imageMetaData As DirectReadOptions) As ImatestTask
Parameter Name Data Type Description
imageFilePath string A file path to an image
imageFilePaths IEnumerable<string> A collection of file paths to images
imageData byte[], UInt16[], UInt32[] Raw image data (if you are using direct read mode)
module enum (ImatestLibrary) A flag telling Imatest IT which module to run. Valid values are contained in the ImatestModule enum:
ImatestModule.Blemish
ImatestModule.Checkerboard
ImatestModule.Colorcheck
ImatestModule.Distortion
ImatestModule.DotPattern
ImatestModule.eSFRISO
ImatestModule.Multitest
ImatestModule.Random
ImatestModule.SFR
ImatestModule.SFRplus
ImatestModule.SFRreg
ImatestModule.Star
ImatestModule.Uniformity
ImatestModule.Wedge
imageMetaData DirectReadOptions An instance of the DirectReadOptions class that contains image meta data, used to help interpret the raw byte data.

Add each of your tasks to a collection of type ImatestTask, then call Library.ParallelAnalyzer.Execute(), passing in the path to your INI file for iniFilePath, true for runInParallel, and the number of worker processes you’d like to use:

string inFile = "C:\\images\\ini_file\\imatest-v2.ini";

List&lt;ImatestTask&gt; lstTasks = new List&lt;ImatestTask&gt;();
lstTasks.Add(ImatestTask.Create("C:\\images\\sfrplus_0123.jpg", ImatestModule.SFRplus));
lstTasks.Add(ImatestTask.Create(new List&lt;string&gt;() { "C:\\image\\blemish_0001.jpg", "C:\\images\\blemish_0002.jpg", "C:\\images\\blemish_0003.jpg" }, ImatestModule.Blemish));
....

string result = library.ParallelAnalyzer.Execute(lstTasks, iniFile, true, 2);
Dim iniFilePath As String
Dim lstTasks As New List(Of ImatestTask)()
Dim result As String

iniFilePath = "C:\\images\\ini_file\\imatest-v2.ini"

lstTasks.Add(ImatestTask.Create("C:\\images\\sfrplus_0123.jpg", ImatestModule.SFRplus))
lstTasks.Add(ImatestTask.Create("C:\\image\\blemish_0001.jpg" ImatestModule.Blemish))

List&lt;ImatestTask&gt; lstTasks = new List&lt;ImatestTask&gt;();
lstTasks.Add(ImatestTask.Create("C:\\images\\sfrplus_0123.jpg", ImatestModule.SFRplus));
lstTasks.Add(ImatestTask.Create(new List&lt;string&gt;() { "C:\\image\\blemish_0001.jpg", "C:\\images\\blemish_0002.jpg", "C:\\images\\blemish_0003.jpg" }, ImatestModule.Blemish));
....

result = library.ParallelAnalyzer.Execute(lstTasks, iniFilePath, True, 4)

The result will be a JSON encoded string that can be parsed into an array of result objects using any .NET JSON library. Each result object has this form:

{
   "data": {
      "dateRun": "18-Sep-2017 10:26:59",
      "ini_file_name": "C:\\images\\ini_file\\imatest-v2.ini",
      "ini_time_size": "18-Sep-2017 10:26:45 21822B  MD5 = ac109f86b635bd5b4344d252969e64a7",
      "version": "Imatest 5.0.0  SFRplus",
      "title": "sfrplus_0123.jpg",
      "image_path_name": "C:\\images\\sfrplus_0123.jpg",
      
      ...
   },
   "errorID": "",
   "errorMessage": "",
   "errorReport": ""
}

If any exceptions occurred during processing, they will be reported in the errorID, errorMessage, and errorReport properties. While handling your results, you should always check whether the errorID property is empty or not before working with the data property.

 

Arbitrary Charts Module

Starting with version 5.0, Imatest IT now allows you to call the new Arbitrary Charts module in using the new arbitrary_cahrts functions. For more information on the Arbitrary Charts modules, see this article.

Interface Type:
Coming soon…
Coming soon…

First, create an image options dictionary by calling ImatestLibrary.get_arbitrary_charts_options():

ImatestLibrary.get_arbitrary_charts_options(self, width=None, height=None, encoding=None, filename=None, extension=None, pixel_size=None)
Parameter Name Data Type Description
width int Image width (in pixels)
height int Image height (in pixels)
encoding str The pixel encoding (i.e., “srgb”, “intensity”)
filename str (direct read only) The name of the file, used for results file names.
extension str (direct read only) The extension key used to decode the direct read image bytes, as configured in the Read Raw screen of Imatest Master.
pixel_size enum (direct read only) The pixel size of the direct read image. Use one of these constants:
ImatestLibrary.PIXEL_SIZE_8_BIT_UNSIGNED
ImatestLibrary.PIXEL_SIZE_16_BIT_UNSIGNED
ImatestLibrary.PIXEL_SIZE_32_BIT_UNSIGNED

Once you have the options object, you can then call the one of the arbitrary_charts functions:

ImatestLibrary.arbitrary_charts_separate(self, image_files=None, image_data=None, chart_file=None, ini_file=None, options=None)
ImatestLibrary.arbitrary_charts_signal_average(self, image_files=None, image_data=None, chart_file=None, ini_file=None, options=None)

The arbitrary_charts_separate function will analyze multiple inputs separately, while the arbitrary_charts_signal_average function will combine two images’ results into a single signal averaged result.

Parameter Name Data Type Description
image_files str or list of strs Either a file path to an image, or a list of file paths
image_data str/bytes or array.array (numerical) If you are providing raw image data, use this argument, which is either the read value of the image in str (Python 2.7, 3.3, 3.4) or bytes (Python 3.5) form. If using image_data, you must include the required parameters into the ImatestLibrary.get_arbitrary_charts_options() method
chart_file str The path to the chart definition file.
ini_file str The path to the INI file.
options dict The dict object returned by calling ImatestLibrary.get_arbitrary_charts_options().

The result will be a JSON-encoded string, which can be converted to a dict using json.loads(), of this form:

{
    "Info": {
        "Timestamp": "04-Oct-2017 09:09:08",
        "Version": "Imatest 5.1.0.25883 Alpha ",
        "Build": "2017-10-03",
        "Calculation_time_seconds": [44.36107732]
    },
    "Results_array_sources": "C:\\images\\P1858_combination_chart_example.jpg",
    "Results": {
...
    }
}

First, create an ArbitraryChartOptions object:

ArbitraryChartOptions arbChartOptions = new ArbitraryChartOptions();
arbChartOptions.Encoding = ImageEncoding.sRGB;
arbChartOptions.Width = 1296;
arbChartOptions.Height = 808;
Dim arbChartOptions As ArbitraryChartOptions
arbChartOptions = new ArbitraryChartOptions()
arbChartOptions.Encoding = ImageEncoding.sRGB
arbChartOptions.Width = 1296
arbChartOptions.Height = 808
Property Name Data Type Description
Width int Image width (in pixels)
Height int Image height (in pixels)
encoding enum (ImageEncoding) The pixel encoding:
ImageEncoding.sRGB
ImageEncoding.Intensity
Filename string (direct read only) The name of the file, used for results file names.
Extension string (direct read only) The extension key used to decode the direct read image bytes, as configured in the Read Raw screen of Imatest Master.

Once you have the ArbitraryChartOptions object, you can then call the one of the ArbitraryCharts methods:

public string Separate(string inputFile, string chartFile, string iniFile, ArbitraryChartOptions options);
public string Separate(IEnumerable&lt;string&gt; inputFiles, string chartFile, string iniFile, ArbitraryChartOptions options);
public string Separate(byte[] imageData, string chartFile, string iniFile, ArbitraryChartOptions options);
public string Separate(ushort[] imageData, string chartFile, string iniFile, ArbitraryChartOptions options);
public string Separate(uint[] imageData, string chartFile, string iniFile, ArbitraryChartOptions options);
public Task&amp;lt;string&amp;gt; SeparateAsync(string inputFile, string chartFile, string iniFile, ArbitraryChartOptions options);
public Task&amp;lt;string&amp;gt; SeparateAsync(IEnumerable&amp;lt;string&amp;gt; inputFiles, string chartFile, string iniFile, ArbitraryChartOptions options);
public Task&amp;lt;string&amp;gt; SeparateAsync(byte[] imageData, string chartFile, string iniFile, ArbitraryChartOptions options);
public Task&amp;lt;string&amp;gt; SeparateAsync(ushort[] imageData, string chartFile, string iniFile, ArbitraryChartOptions options);
public Task&amp;lt;string&amp;gt; SeparateAsync(uint[] imageData, string chartFile, string iniFile, ArbitraryChartOptions options);
public string SignalAverage(IEnumerable&amp;lt;string&amp;gt; inputFiles, string chartFile, string iniFile, ArbitraryChartOptions options);
public Task&amp;lt;string&amp;gt; SignalAverageAsync(IEnumerable&amp;lt;string&amp;gt; inputFiles, string chartFile, string iniFile, ArbitraryChartOptions options);
Public Function Separate(inputFile As String, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As String
Public Function Separate(inputFiles As IEnumerable(Of String), chartFile As String, iniFile As String, options As ArbitraryChartOptions) As String
Public Function Separate(imageData() As Byte, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As String
Public Function Separate(imageData() As UShort, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As String
Public Function Separate(imageData() As UInteger, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As String
Public Function SeparateAsync(inputFile As String, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As Task(Of String)
Public Function SeparateAsync(inputFiles As IEnumerable(Of String), chartFile As String, iniFile As String, options As ArbitraryChartOptions) As Task(Of String)
Public Function SeparateAsync(imageData() As Byte, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As Task(Of String)
Public Function SeparateAsync(imageData() As UShort, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As Task(Of String)
Public Function SeparateAsync(imageData() As UInteger, chartFile As String, iniFile As String, options As ArbitraryChartOptions) As Task(Of String)
Public Function SignalAverage(inputFiles As IEnumerable(Of String), chartFile As String, iniFile As String, options As ArbitraryChartOptions) As String
Public Function SignalAverageAsync(inputFiles As IEnumerable(Of String), chartFile As String, iniFile As String, options As ArbitraryChartOptions) As Task(Of String)

The ArbitraryCharts.Separate methods will analyze multiple inputs separately, while the ArbitraryCharts.SignalAverage method will combine two images’ results into a single signal averaged result.

Parameter Name Data Type Description
inputFile(s) string or IEnumberable Either a file path to an image, or a list of file paths
imageData byte[], UInt16[], UInt32[] Raw image data (if you are using direct read mode)
chartFile str The path to the chart definition file.
iniFile str The path to the INI file.
options dict The ArbitraryChartOptions object.

The result will be a JSON-encoded string, which can be parsed using any .NET JSON library, of this form:

{
    "Info": {
        "Timestamp": "04-Oct-2017 09:09:08",
        "Version": "Imatest 5.1.0.25883 Alpha ",
        "Build": "2017-10-03",
        "Calculation_time_seconds": [44.36107732]
    },
    "Results_array_sources": "C:\\images\\P1858_combination_chart_example.jpg",
    "Results": {
...
    }
}