This article focuses on how to improve the performance of Imatest IT testing using configuration (ini file) settings.

Limiting the number of regions used to test, limiting the size of the regions

API Section Settings

Disable messages and figures

[api]

nomsg = 1

disable_figs = 1

Settings for Slanted-Edge modules:
SFR, SFRplus, eSFR ISO, Checkerboard, SFRreg

Many of the settings described here are also listed in  Using Rescharts slanted-edge modules Part 2: Speeding up runs. (Although Imatest IT does not run Rescharts directly, Rescharts is used in Imatest Master to make and save settings that can be used in several fixed modules as well as Imatest IT.)

Enable the “speedup” setting, this disables noise & histogram calculations which are probably not necessary for manufacturing tests.  Will achieve about a 6% speed increase.

speedup = 1     

Enable Luminance (Y) channel-only (single color channel) calculation.  This skips the MTF calculations for the RGB channels. [RGBY_value from 1 to 4 calculates all four RGBY channels, emphasizing R, G, B, or Y, respectively). RGBY_value from 5-8 calculates one individual R, G, B, or Y channel.]

RGBY_value = 8

Disable Edge roughness calculations.

edgerough = Min

Disable the Acutance (formerly SQF) calculation if not needed.

anlz_sqf = 0

Turn off outputs you don’t need, keep JSON outputs which are the most useful

saveCSV = 0
saveXML = 0
saveJSON = 1

Beyond INI file settings these are additional ways of speeding up:

• Run multiple tests in parallel using Imatest IT Parallel
• decrease the number of selected SFR regions to a minimum
• disable other calculation settings that are not necessary
• Use the DLL version of Imatest IT instead of the EXE
• Use direct passing of image data in an array instead of a file on disk
• Throw hardware at the problem.  Imatest loves to have lots of CPU cores to calculate its Fourier transforms, our 6-core LGA-2011 i7 processors are screaming fast.  The more cores the merrier, clock speed is also your friend.

Imatest is integrated with the the MATLAB Image Acquisition toolbox and can acquire images from a multitude of analog frame grabbers. The following manufacturers provide frame grabbers that support a variety of standard and non-standard analog cameras including NTSC, PAL, RS-170, CCIR, and progressive scan. Please see vendor’s Web site for more details.

Frame grabbers will become part of the image processing pipeline, and therefore could either enhance or degrade the quality of the video signal.  Not all frame grabbers will behave the same. (more…)

The settings for a Visual Studio project file require that you have proper path includes that point to the appropriate Imatest IT library and Matlab Compiler runtime libraries.

In Visual Studio, from the Projects menu select Properties

Enter these settings:

C/C++ -> Additional Include Directories

3.10+

“C:\Program Files (x86)\MATLAB\MATLAB Compiler Runtime\v81\extern\include”

3.9 and below

“C:\Program Files (x86)\MATLAB\MATLAB Compiler Runtime\v714\extern\include”

Linker -> Input -> Additional Dependencies

3.10+

“C:\Program Files (x86)\MATLAB\MATLAB Compiler Runtime\v81\extern\lib\win32\microsoft\mclmcrrt.lib”;
“C:\Program Files (x86)\imatest\IT\libs\sfr\cpp\imatest_sfr.lib”;       (replace sfr with the module you are using)

3.9 and below

“C:\Program Files (x86)\MATLAB\MATLAB Compiler Runtime\v81\extern\lib\win32\microsoft\mclmcrrt.lib”;
“C:\Program Files (x86)\imatest\IT\libs\sfr\cpp\imatest_sfr.lib”;       (replace sfr with the module you are using)

Linker -> System

Enable Large Addresses

Yes (/LARGEADDRESSAWARE)     – Required for testing images over 10 Megapixels with blemish detect

32 bit supports ends as of Imatest version 4.5

A 64-bit OS with 8GB of RAM is recommended

There are many advantages to running an operating system and software that matches your computer’s architecture, which is probably 64 bit. While 32 bit has always been problematic (see below), we continued to support it as long as possible, but MATLAB ended support for 32 bit as of release 2016a. 

32 bit operating systems typically access no more than around 3.2 Gigabytes of total memory… even with 4GB installed.  Usually the PC system is already using several gigabytes of memory, leaving little available memory to test images with Imatest.  

Imatest will not use virtual memory for its calculations so a system with adequate available memory is important to the successful operation of the program.  While 32 bit operating systems will run Imatest, the size of the images you can test is limited to the size of your available memory, which is often under 1 Gigabyte.

A 64 bit operating system is recommended for using Imatest to test images larger than 10 megapixels.

The 32 bit version of Imatest running on a 64 bit operating system will be able to access up to 4GB of memory.  There is a 64 bit version of Imatest available, but only required if you are testing extremely large images ( > 80 Megapixels).

Many users install 32-bit operating systems on 64 bit hardware.  This is a mistake. A 64-bit OS should be installed on 64-bit hardware.

There is no advantage to having over 4 gigabytes of memory if you run a 32 bit OS.

Memory usage in Imatest

When Imatest starts, two lines in the command window display memory availability.

Memory: Array max/total = 2047/3375MB;  MemUsedMATLAB = 448;  System = 8181MB
   Virtual: avail/total = 3375/4096MB;  Physical: avail/total = 2868/7987MB

The total physical memory (RAM) for this system (shown above) is 7989MB (i.e., 8GB).

If Imatest runs out of memory, the following line appears in the command window and in the Error Occurred window.

Out of memory. Type HELP MEMORY for your options.

The Colorcheck module is particularly sensitive to memory availability. (Multitest and Multicharts, which perform all Colorcheck functions, can work with much larger images.) We have seen Imatest run out of memory in Colorcheck for a 16 Megapixel image on a 32-bit OS with 3GB RAM and for a 36 Megapixel image for 32-bit Imatest running on a 64-bit OS with 8GB RAM. Running 64-bit Imatest solved the problem.

Error message

Issue: Path conflicts when other versions of Matlab are installed

If a different version of Matlab from the one used for Imatest (6.5.1) has been installed on your system, there is a tiny chance that you may experience a path conflict that causes a similar error message— or Imatest may simply fail to run. This rarely happens because the batch file that initiates Imatest sets the path. Path issues and solutions are discussed in the Imatest IT EXE instructions.

Imaging-resource.com publishes images of the Imatest Log F-Contrast* chart in its excellent camera reviews. These images contain valuable information about camera quality— how sharpness and texture response are affected by image processing— but they need to be processed by Imatest to reveal the important information they contain.

*F is an abbreviation for Frequency in Log F-Contrast.

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Roger Cicala of LensRentals.com has completed the second part of his two part series investigating lens testing. (more…)

Imatest 3.10 Released

The latest version of Imatest has been optimized for speed and includes many improvements and new features. A new image stabilization module allows users to test the efficacy of a camera’s optical image stabilization (OIS). To see a rundown of all of the new additions to version 3.10, take a look at our blog detailing the release. (more…)

The release of version 3.10 of Imatest brings a host of improvements to make image quality testing faster and more relevant to advances in cameras. Look for performance, stability, interface and measurement improvements across the board as well as some excellent new modules and features. (more…)

Imatest currently sells several transmissive (backlit) test charts, which have a range of substrates, each with specific properties and qualities that are in process of being quantified. The following comparison of the most important of our transmissive substrates was prepared in response to several customer inquiries.

(more…)

The week before the conference, we invite you to join us for our two day Imatest Training Class taught by Norman Koren, creator of Imatest. This will be happening at the Larkspur Landing in Campbell (near Cupertino) on January 29 & 30. Both days run 8:30 a.m. – 5:00 p.m, but usually goes later for additional questions & answers.   You can register online or contact sales@imatest.com with questions.

The following week, on D we will be having a booth at Electronic Imaging 2014.    This will be held at the Hilton San Francisco Union Square.  Our booth will be staffed by our stable of Imaging Scientists, we will be giving live demonstrations of real-time camera testing.

We hope to see you there!

Calendar

Location

This event is passed.  Thanks for your interest.  

We’ll be back in Silicon Valley early next year for Electronic Imaging 2014

Join us for a free presentation & demonstration of Imatest Software tools for testing image quality on October 23 from 2:30 – 5:30PM.

The presentation will last about one hour with informal questions & answers afterwards.   We will be serving drinks and snacks.

The presentation will be held at the Larkspur Landing in Sunnyvale

View Larger Map

Our two day training class will be on October 24 and 25 from 9:30 in the morning to 5:30 in the evening at the Larkspur landing in Campbell (not the Sunnyvale location where the presentation will be held). Please see here for a detailed agenda for the training.

Register for our training course on our store or contact training@imatest.com for more information.

Using Babelcolor Patch Tool or SpectraShop 4

This post describes how to measure color and grayscale patches on a variety of test charts, including Imatest SFRplus and eSFR ISO charts, the X-Rite Colorchecker, ISO-15729, ISO-14524, ChromaDuMonde CDM-28R, and many more, using a spectrophotometer and one of two software packages.

• Babelcolor PatchTool  which works with reflective test charts
• Robin Myers SpectraShop 4  which works with both reflective and transmissive (backlit) test charts

(more…)

Imatest does not support international characters in file name paths.  Using files with international characters will corrupt the Imatest INI file and lead to an INI file error.

You should only use folders and filenames with latin characters or you will encounter this problem.

Resetting your Imatest INI is the easiest way to solve this problems.  You can do this through the following menu entry:

This will remove the settings that you have made within imatest.

To correct the problems with your INI File you can follow the troubleshooting information information available here

Symptoms of problem:

Upon selection of a region of interest, program stops working, either not responding or crashing.

DOS window error messages: 

• Operation terminated by user during pause (line 21) In newROI_quest
• Undefined function or method ‘figure1_KeyPressFcn’ for input arguments of type ‘struct’.

• Error while evaluating figure KeyPressFcn – Segmentation violation detected

Source of problem:  

automatic translation software such as 有道首页 (Youdao Dictionary) and 金山词霸 (PowerWord)

Solution to problem: 

Temporarily disable the translation software while performing a ROI selection

We will be working to make our software compatible with these sorts of translation programs in the future, as well as improving our own internationalization.  Sorry for the inconvenience.

Imatest IT uses the Matlab runtime library which is a single-threaded routine that is not thread-safe.

If your tester application uses multiple threads, you should restrict all the parts that call upon the Imatest library to a single thread.

If your tester application uses multiple processes be careful about using busy waiting in order to check for the results of the test to occur.  Without a sleep statement inside your loop, the rapidly looping process will prevent context switching to other processes, which will prevent them from running and consume a large amount of CPU resources causing both processes to freeze.

If you want to run multiple processes with Imatest calculations, please see:

Can Imatest IT run multiple instances in Parallel?

This event is past, thank you if you participated.  If you missed us, please try to catch us in Shanghai in April.

Training Class Curriculum

Students will learn how to:

• Measure key image quality factors using Imatest
• Understand and interpret Imatest output
• Avoid common mistakes in applying Imatest
• Select appropriate test charts
• Tailor Imatest options to target environments
• Assess overall image quality

Schedule

Stops will include:

• Shenzhen presentation the morning of March 4 with training on March 5 and 6
• Taiwan presentation the morning of March 11, with training on March 12 and 13
• We will also be in South Korea the week of February 25 – March 1, Shanghai March 7-8, Xiamen March 9, Tokyo March 14 & 15

We are providing these training at a 50% discount to our normal rate.

Our schedule is nearly fully booked. Please contact us for any remaining availability for a brief on-site consultation.

Map of locations

View Imatest Asia Tour 2013 in a larger map

(past) Shenzhen Imatest Presentation & Training

Imatest 3.9 was released on December 14th 2012.   Please contact sales@imatest.com for purchase or renewal information.

Here is a complete list of changes:

Imatest main window: Explore image file folder and Explore recent save folder have been added to the File dropdown. INI File Settings have been given their own dropdown to minimize clutter. Explore INI file folder has been added. The INI file Editor (useful for fixing errors and for setting up INI files for the Functional Interface and IT) has been greatly enhanced. (more…)