Imatest Instructions – Getting started

• • Chrome on glass (up to 4×4 inches (100x100mm; ultra-fine; no grayscales)),
  • Color photographic film (up to 8×10 inches; fine; low noise),
  • Black & White film (up to 12×20 inches; noisier than color; good for NIR and SWIR (Near and Shortwave Infrared)),
  • Photographic paper (finer than inkjet and better for NIR and SWIR), and
  • Inkjet (up to 44 inches high; too coarse to be suitable for very small charts). You can print your own inkjet charts, but for highest quality we recommend purchasing them from the Imatest store.

We encourage customers to contact charts at imatest dot com with questions about chart suitability. Let us know your camera’s pixel resolution and field of view. 

Running Imatest

Imatest is opened by

• double-clicking the Imatest icon on the Desktop,
• from Windows Start menu: Start → All Programs → Imatest  → Version →   Imatest Edition , illustrated on the right.
• or from the Imatest directory, typically C:\Program Files (x86)\Imatestversion (where version is Master, IS, Studio, etc.) in win64 English language installations.

After several seconds (up to a minute after the first installation or a reboot), the Imatest main window, shown below, opens.

In the New Imatest Main Window, user can select an image, and select the analysis to be run. (This can be done in either order.) Click the “Analyze” button to run. If ROI selection, or other settings are required, a window will pop up, for user entry. (If using the Classic UI, Imatest analysis modules are run by clicking on one of the buttons in the left two columns.)

Table of contents.

 

Finding Imatest Help

• Comprehensive Imatest help can be found on the Documentation page (the Table of Contents). 
• The Learn icon (top menu in the Imatest software) has links to important online documentation.
• Tooltips (blocks of text that appear for a few seconds when you hover the mouse above a button) contain concise descriptions of the button function. 
• In the Classic UI, right-clicking on most buttons in the Imatest main window (including the tabbed box on the right) opens a help document for the button function.  
• VIDEOS and Online training are available.

 

If you’re starting out, sample images for several modules can be downloaded from Github.

Saved settings: imatest-v2.ini

Settings are saved in an INI file named imatest-v2.ini, described in detail in Saved settings (INI files) and in theManage settings button in the  Data tab .

Settings include Font size, folders for opening and saving images, calculation parameters, plot selection, and figures to display and save. Several INI file utilities can be accessed from the INI File dropdown menu, described below. You can view or edit the settings withINI file editor orView settings (ini file), save or load ini files, and do much more.

You can perform a number of functions related to troubleshooting and fixing errors, described in Saved settings (INI files), Troubleshooting, and the important Knowledge base post, A module that formerly worked has stopped working. The INI File Index, which will be of interest to advanced users, contains a description of the INI file monitor. 

Display dropdown menu

 

The Displaydropdown menu contains important settings that affect font, windows, and figure size. You should set fonts be the right size relative to the image: not too small, which makes test difficult to read and doesn’t utilized space reserved for text, and not too large, which causes text to cover other objects.

Display dropdown menu in the Classic Imatest UI : Font and window size settings

A really early version of Imatest Imatest has several settings to adjust font and window size for the DPI scaling of different computers. To access these, click Display (on the top bar of the main window), which opens the dropdown shown on the left. Settings: Font size: set it so it appears correct in figures, i.e., not too small or large. Normal or enlarged screen (Imatest main window). Normal or enlarged figures (1.25 or 1.5x). You may need to enlarge the font for enlarged figures. Normal or enlarged interactive windows (Color/Tone Interactive, Rescharts, Batchview, etc.)

 

Open the image file

Most Imatest analysis modules require an image file to be opened.

When you open the module (in some cases) or push a button to open an image file (in other cases), a dialog box opens that requests the name of the image file. Supported image file formats are summarized below.

Supported image file formats

See Image file formats and acquisition devices for full details. Summary: Any file type supported by the Matlab imread statement. Rarely used formats grayed out. BMP — Windows Bitmap JPEG (JPG) PNG — Portable Network Graphics CUR — Cursor File JPEG 2000 (JP2, JPX) PPM — Portable Pixmap GIF — Graphics Interchange Format PBM — Portable Bitmap RAS — Sun Raster HDF4 — Hierarchical Data Format PCX — Windows Paintbrush TIFF (TIF) 8-48 bits Multi-image TIFFs are supported. ICO — Icon File PGM — Portable Graymap XWD — X Window Dump Commercial raw formats converted using Libraw. These include CR2, NEF, RW2, and many more. See LibRaw 0.20 supported cameras. New cameras are typically added to LibRaw within a month or two of their introduction. Binary files identified by extensions specified in the Generalized Read Raw window. You can set the pixel size,bit depth, demosaicing parameters, offset, etc., for the extension. TGA (Targa) Video formats, including DPX, Video DNG*, and ARI* (*converted using LibRaw) CSV (a special format used in some infrared systems) HDR  High dynamic range files A large variety of image acquisition devices— too many to list here.

Multiple file read (batch mode)  You can select several files to read. Depending on how you respond to the multi-image dialog box (below), Files can be analyzed individually in sequence (batch mode), Files can be combined— averaged— and the mean can be analyzed (and also be saved if needed). This can reduce noise (by a factor of √N for N files), making MTF calculations more accurate. Signal averaging is also useful for measuring sensor fixed pattern noise in Stepchart, Colorcheck, Color/Tone Interactive, Color/Tone Auto, and Uniformity, For two input files, you can calculate temporal noise with Stepchart, Colorcheck, Color/Tone Interactive, or Color/Tone Auto, For 4-16 input files (8 recommended), you can calculate temporal noise with Color/Tone Interactive or Color/Tone Auto. The files should be in the same folder, have the same pixel dimensions (for most modules), and be framed identically (except for SFRplus and other modules that use automatic detection, where they can be any size). If you choose Combine files, you’ll have the option of saving the combined file with 16-bit TIFF format as default. Batch mode is not supported in interactive modules such as Rescharts or Color/Tone Interactive. For combined files, the saved file name is the same as the first selected file name with _comb_n appended, where n is the number of combined files.

• Enter additional input data. Unless Express mode has been selected, a Settings window opens that settings data, depending on the module. Most additional data is optional (and is saved from previous runs); you only need to pay attention to settings you wish to change. Click OK to run the program or Cancel to terminate the run.
• Save results? After an analysis has been run, a dialog box asks if you would like to save the results. Checkboxes in the dialog box enable you to select the Figures, CSV (Excel-readable), and JSON files to be saved. You can examine the results before deciding which, if any, to save. (The Save box is omitted in the evaluation version.) Figures can be saved as PNG (losslessly-compressed) image files or Matlab Fig files (not recommended because of their large size. Fig files can be opened and manipulated with Open Fig file.

Helpful buttons

In the New Main window, click on the “Learn” Tab – to learn about Imatest Image Analysis, Charts, IQFs and Standards. It also has links to the Educational Apps. Or, click on Help menu on the top menu bar.

 

Buttons below are used to access help in the Classic UI.

Each of these buttons, which are in the tabs on the right of the image, opens a large Help window with lots of explanations and buttons that open a variety of functions. You should familiarize yourself with them and use them whenever the need arises.

Help guide (in the Help tab) opens a window with links to some of the most useful instruction web pages as well as brief explanations of what they contain, including Registration quickstart | Imatest instructions | Image quality factors | Imatest tour | Table of Contents (site map) | FAQ | Change Log | Testing lenses | MTF Curves & Appearance | SFRplus | Troubleshooting.

Manage settings (in the Data tab) opens a window that explains some of the key functions for setting and examining the contents of the file for saving Imatestsettings, imatest-v2.ini. It also displays the full path name to imatest.ini and shows how to fix bugs that can arise when imatest-v2.ini is corrupted. Function buttons include Save settings…, Load settings…, View/Edit settings (ini file), Copy settings (ini file), Import / Merge settings, Edit / Reset Modules, and Reset Defaults (all).

Error handling (in the Data tab) opens a window that shows what to do if you encounter an error. It includes link to the Change Log and Troubleshooting pages, buttons for Copying the current or last session to the clipboard for pasting into emails, and instructions on fixing imatest.ini when it gets corrupted.

Raw files

Raw files are the unprocessed output of digital image sensors. For Bayer sensors, each raw pixel represents a single color in RGRGRG, GBGBGB, … sequence. To be converted into usable, standard file formats (TIFF, JPEG, etc.), raw files must be processed by a raw converter. Raw converters perform several functions: demosaicing (converting the Bayer sequence into full color), applying a gamma curve, often with an additional tonal response curve, color correction and white balance, reducing noise, and sharpening the image. These operations affect Imatest measurements, especially sharpness (MTF or SFR).

The best way to be sure an image file faithfully resembles the raw file— that it has minimal processing— is to read a raw file into Imatest and convert it into a standard format (typically TIFF) using LibRaw for commercial raw files (identified by extension: CR2, NEF, etc.) or Generalized Read Raw for binary development files (also identified by extension, often RAW). For commercial raw files, the dialog box on the right appears. It allows you to choose among several raw conversion options. Details for both commercial and binary files can be found in Raw files.

Raw files can be converted with demosaicing (standard RGB format) or without demosaicing (which allows the original R, G(R), B, G(B) channels to be analyzed separately.

Exit closes all figures and terminates Imatest.

Close figures closes all figures. Important because the computer will slow down if too many are open. You can close figures individually by the usual Windows methods — clicking the X in the upper right or right-clicking on the figure icon on the Taskbar and selecting Close.

EXIF (in the Utility dropdown menu) displays EXIF metadata for an image file. Most file formats supported when ExifTool is installed (instructions below). EXIF data can be alphabetized to facilitate locating settings, copied to the clipboard (for pasting into a text editor), and saved in a text file in the same folder as the image file.

EXIF viewer

 

Options and Dropdown menus

We can only summarize the highlights of the Options windows and the dropdown menus because a full list of the settings and functions would be overwhelming (and difficult to keep up-to-date).

ROI Options and Options II… (in the Settings dropdown menu) opens the windows shown below, which allow several options to be specified.

ROI Options

Modules that offer automatic ROI selection (shown in the pink area below) also allow manual selection because automatic detection may fail on blurred, badly exposed, badly framed, or noisy images, as well as images with cluttered surroundings (neutral gray is always preferred).

Options I for setting ROI options and selection method (manual/auto)

Use new ROI selection method Opens a different window for selecting regions. It allows more flexibility in selecting multiple regions (SFR and Wedge), but frequently crashes. We recommend unchecking it for other modules.

ROI (Region of Interest) section controls cropping options.

• SFR ROI filtering When Light filtering is checked the tests that validate the SFR ROI (region of interest) are relaxed. This can be useful when testing noisy images, rough edges, images of endoscopes or other devices with interfering patterns, but it can lead to errors if regions are selected carelessly. Normal filtering is the default.
• Stepchart ROI selection Automatic patch detection (following manual region selection) can be toggled. If it is turned off, a fixed number of patches (6-41) can be selected for Stepchart analysis. This option is useful when high noise in dark regions confuses the automatic ROI detection.
• Colorcheck, Distortion, Light Falloff Cropping options. You can select whether to ask for cropping and whether to use the last crop (for same-sized images). For Colorcheck you can also choose between traditional automatic patch detection and Color/Tone Interactive-like patch detection, where all squares are shown in the fine adjustment window.
• ROI selection (Manual or Auto) can be selected for several modules. The  Auto ROI selection (global)  area lets you override the individual selections, as indicated. 
  Automatic ROI selection (detection) is supported by several test charts:  Colorchecker (in Colorcheck and Color/Tone), Random (Spilled Coins, Dead Leaves), 36 patch Dynamic Range, Contrast Resolution, ISO 14524*, ISO 15739*, Log F-Contrast*, Siemens Star*, and Rezchecker (versions with dots in four corners).  *recent versions of these charts with registration marks in the corners.
  New in 2021.2:  The Matlab Colorchecker auto-ROI method (9 and 10) has been added to the many options available for the Colorchecker chart.

Colorchecker ROI selection options: 2,3,9, and 10 are for auto detection. 9 and 10 are new in 2021.2

Reset restores defaults: it sets SFR ROI filtering to Normal, Stepchart ROI selection to Automatic.

Options II

Options II for setting numerous options

Global folders The default folders for opening files and saving results can be set globally using the second group of controls. Normally (with Global folder for opening files unchecked), the default folder for opening files is changed only for the Imatest module in use: one module at a time. When it is checked, the default folder for opening files is changed for all modules. This can be convenient if project data for several modules is stored in the same file.

When Global folder for saving results is checked, the default save folder is changed for all modules whenever the input folders are changed.

EXIF data acquisition settings This selects the program used to read EXIF data: image file metadata that contains camera and lens settings. Selected EXIF data (important values such as aperture, exposure time, ISO speed, and focal length) is displayed in several figures and EXIF data is saved in CSV and JSON output files. There are four settings:

1	Do not get EXIF data (for rare cases of errors)	EXIF off
2	Get EXIF data from Phil harvey’s ExifTool (all file types; must download & install)	Recommended
3	Get EXIF data from ExifTool & save ALL EXIF data in csv output (LOTS)!	Detailed!
4	Get EXIF data from Matlab’s built-in function (limited)	Limited results

Recommended settings 2 and 3 (ExifTool) work with virtually any file type and capture virtually all available EXIF data. If the setting 3 (save ALL EXIF) is selected, all the EXIF data— a large amount; some quite obscure— is written to the CSV output files. Setting 4 (Matlab’s built-in function) returns limited results. Setting 1 is for rare cases that cause EXIF read to crash (it’s also faster).

The second and third settings require ExifTool, which is included in Imatest installations, but is frequently updated. If you need a newer version,

• Go to the ExifTool home page and download the Windows standalone executable (a zip file).
• In Windows Explorer, double-click on the downloaded zip file.
• Copy the contents ( exiftool(-k).exe ) to the appropriate installation folder. To find the location in Imatest 5.0+, click Open utilities folder to the right of EXIF data acquisition. In older versions you will need to search for exiftool in C:\Program Files\Imatest\ or C:\ProgramData\Imatest\ (including subfolders). [In my (English-language) computer the location for Imatest Master 4.2 is C:\Program Files\Imatest\v4.2\Master\imatestis_mcr\depends\RTDepends. The location for Imatest  Master 5.0 is C:\ProgramData\Imatest\mcr_cache\5.0\Master\mcrCache9.2\imates0\depends\RTDepends.]
• Rename exiftool(-k).exe to exiftool.exe.

EXIF color space settings can be confusing because two tags affect color space, and their relationship is not logical. Color space (where you would logically expect to find the color space) can contain either sRGB (the Windows/Internet standard) or Uncalibrated (1 or 65535). If Color space is Uncalibrated, the color space is located in the Profile Description tag, which can be interpreted as Adobe RGB, Display P3, etc. (Did I say not quite logical?) See www.exiv2.org/tags.html

YUV format  Imatest supports several flavors of YUV file, which can be selected. Details here.

DNG (Adobe Digital Negative) file reading  lets you select how DNG files are processed. Details here. 

Suffix for saved SFR plots and CSV and JSON files Normally the root name (input or selected file name ) is followed by the channel, ROI orientation (AL = above left (relative to the center), etc.) and distance from the center in percentage of distance to the corner. Example: rootname_YAL79_MTF.png for the Edge/MTF plot. An alternative can be selected where _ROI_ followed by the ROI number nn is used in place of the orientation and distance. Example: rootname_ROI_03_MTF.png

Special user code enables custom features for specific users. Normally blank.

Reset restores defaults: it sets SFR ROI filtering to Normal, Stepchart ROI selection to Automatic, turns off all global folder settings, and checks Get EXIF data .

Help opens a relevant web page on computers connected to the Internet.

The Options III window (not shown) contains some obscure settings (with explanation text) that most users won’t want to change. The Luminance Calculation lets you choose between the Rec. 709 luminance (Y) calculation:  Y = 0.2125*R + 0.7154*G + 0.0721*B (default; newer) and the older calculation:  Y = 0.3*R + 0.5G*G + 0.11*B (older; not recommended).

Dropdown menus

Dropdown menus are located at the top of the Imatest main window. Most items duplicate the controls elsewhere in the window, but some are unique.

Because so many features and utilities are available in the dropdown menus, it is difficult to keep this page up-to-date. For this reason we encourage users to explore the contents of the dropdown menus, which contain many valuable utilities and modules. It is one of the best ways to learn Imatest’s features.

 

File 

• View or Copy the Current or Previous Session  are useful for reporting errors and for debugging, as described in Troubleshooting and in the Error handling window.
• System command lets you execute a DOS call on Windows computers through Imatest.
• Memory usage and Clear Memory. Clear Memory removes the image data stored after running SFR. This may make little difference in 64-bit systems.
• Open the recent image file folder, save folder, or INI file folder are highly useful functions.
• Close Figures (important because too many open windows slows Imatest operation) and Exit.

Fixed Modules opens Imatest fixed analysis modules, corresponding to buttons in the first column of the Imatest main window. Fixed modules require that all data be entered before the analysis module is run and results are displayed and saved. Fixed modules can analyze large batches of images.

Interactive Modules/Postprocessors opens interactive modules and postprocessors, corresponding to buttons in the second column. Interactive modules allow you to change settings and explore results while they are open. Several modules operate in either interactive or fixed mode (their names are different, for example, SFRplus Setup (interactive) and SFRplus Auto (fixed)). In such cases, we recommend running the interactive module first to get settings correct before running it in fixed (batch-capable) mode.

Utility opens utility modules. The entries duplicate many of the buttons in the tab area on the right of the Imatest main window, shown above.

Settings contains functions that control various aspects of Imatest operation. Many can be accessed from the Manage settings window.

• IT options sets several options for controlling IT (Industrial Testing) runs.
• Small / Normal / Large fonts alters the font size in output figures and GUI windows. The default is Normal. The setting is saved between runs. This address problems with tiny fonts in high resolution screens (1600x1200 pixels and above) or larger than expected fonts which appear when the video card DPI setting is Large size (120 DPI) instead of Normal. The video card setting can be accessed by right-clicking on the Windows background, then clicking Properties, Settings, Advanced, General (tab). Large fonts are displayed if DPI is set to Large size (120 DPI). 96 DPI is normal. Windows may need to be rebooted before new settings take effect.
• ROI Options (described above) contains settings that affect ROI (region of interest) settings and chart configuration settings for several Rescharts modules and grayscale step charts.
• Options II  and III contain a number of settings described above.
• DOS command allows you to enter a DOS command while Imatest is running. Useful for troubleshooting, for example, for diagnosing path issues.
• When checked, Fixed sharpening radius keeps the SFR standardized sharpening radius fixed, even for edges with poor MTF where it would otherwise automatically increase.
• Enlarge hi res figs applies only to high resolution screens (1600x1200 pixels and above). When this box is checked (by default), images are enlarged so they don’t look tiny on the screen. Unchecking the box turns this feature off. Images are smaller but better suited for website presentation. The setting is saved.

Display contains settings that affect font and windows sizes. Described above.

INI File Settings contains operations that affect saved Imatest settings (the contents of imatest-v2.ini and other INI files). Many can be accessed from the Manage settings window. Learn more in Saved settings.

• Manage Settings opens the Manage settings window.
  
• Save Settings copies the current active settings from imatest-v2.ini to a named file (with extension ini). Particularly useful for saving regions of interest (ROIs) for SFR runs and for controlling Imatest IT modules. The most recent folder used to save or retrieve settings is displayed in the file selection dialog box, but any folder may be selected.
• Load Settings retrieves settings from a named file (with extension ini) and stores them in imatest.ini. It is useful for restoring ROIs or for restoring settings after they have been reset. The most recent folder used to save or retrieve settings is displayed in the file selection dialog box, but any folder may be selected.
• View/Edit Settings displays the settings— the contents of imatest.ini— in the Notepad viewer. You can edit this file (with care!) and save it as a named file if desired. You can send us the contents of imatest.ini for help with troubleshooting. The Notepad window should be closed when you are finished viewing it: it may interfere with some Imatest operations.
• INI File Editor (formerly Edit/reset module(s)) opens a special editor that allows ini file values to be examined and entire sections to be deleted if the corresponding module crashes. Described in Troubleshooting.
• Scan & repair INI file Scans the INI file for errors that may be introduced when there are non-Latin characters (Chinese, Hebrew, etc.) in path names.
• Reset Defaults (All) restores settings to their default values by resetting imatest.ini. This an extreme measure that sometimes clears bugs. See Troubleshooting. Use only as a last resort. It is a good idea to save settings prior to resetting them.

Help contains Online Help, Register, Register Upgrade, and About, and Welcome window. Many are included with brief explanations in the Help guide window.

• Online Help corresponds to the Help button; it opens a browser window.
• Register and Register Upgrade are used to register Imatest.
• About displays the Imatest version and user registration information.
• Check for updates opens a web page that shows the latest version.
• Welcome window displays the window that normally appears when Imatest is started in evaluation model.
• Several additional web pages, including this one, are included.

 

Troubleshooting — what to do if you encounter a bug

Despite our best efforts (which are continually improving), customers sometimes encounter bugs, in part because we keep adding features (most requested by customers). Bugs can be caused by bad images, a bad sequence of operations, or errors in Imatest code. There are several things you can do when you encounter an error. Most of them can be found in the Troubleshooting page or by pressing Error handling (in the  Help tab).

1. Check the Online My License tool or the Download page to make sure you have the most recent version of the Imatest release allowed by your license.
   If you use the Download page you’ll need to compare your support expiration date with the Change log. You can find the most recent version by clicking on Latest release or the Previous releases version (for example, 2020.1), then clicking on Download upgrade. The current version appears in the Save window, e.g., Imatest-2020.1.14-upgrade.exe. Download the current version if it’s newer than the version you’re running. For detailed highlights of Imatest releases, see Imatest Updates and Features.
   
   
2. Try the technique in A module that formerly worked has stopped working, also described in Troubleshooting. Essentially, you open the INI file editor, select the section corresponding the the broken module (for example, [sfplus]), delete the section, then Save the results. This initializes the settings for the section (you’ll have to reenter them), but often fixes bugs caused by a bad ini setting. 

3. If an error reporting window (shown reduced on the right; click on it to view full-sized) appears, examine the instructions and the error text, and if it’s not obvious (sometime it’s an easy fix, for example, for a missing file), press Send Error Report.  This opens a second window that lets you enter your email address and a description of what happened. Then press Send Error Report (yes, again). We will do our best to fix it.

   It can be extremely helpful if you send the image that was loaded into Imatest when the error occurred. If nothing else, we’ll if we find anything wrong with it.

   Please follow this procedure to report an error. Sometimes we receive screen shots of this window. It’s occasionally useful, but it often lacks information we need to fix the bug (the exact Imatest build, the INI file, and events that preceded the crash).

Figures

Imatest results are displayed in individual windows called Figures. A typical figure— a result of running SFR— is shown on the right.

Figures may be resized, minimized, maximized, or closed using standard Windows operations. In addition, several Windows and Matlab-specific operations can be found in the toolbar at the top of the image.

The first four icons in the toolbar are standard Windows icons: New file, Open, Save, and Print. Open and Save refer to Matlab .fig figures, which should be used sparingly because they require excessive storage. 

Of the remaining icons, Zoom in: is particularly useful. Clicking on it highlights it and enables you to zoom in on regions of the plots. You can click and drag to create a zoom rectangle or you can click on any point to zoom in on that point. Double-clicking anywhere inside the image restores the full unzoomed image.

Data cursor example

Data Cursor, selected on by the toolbar icon, lets you click on a curve and display its coordinates in a small box called a Datatip. Right-clicking on the Datatip lets you can delete it or choose additional options.

In most modules, figures can be saved as either PNG files (a standard losslessly-compressed image file format) or as Matlab FIG files, which can be opened by Open Fig file in the Utility dropdown menu, then manipulated (zoomed and rotated). PNG files are usually preferred because FIG files require much more storage, especially for 3D FIG files, which can be rotated. 

Too many open Figures

Figures can proliferate if you do a number of runs, especially runs with multiple regions. System performance degrades if too many Figures are open. Figures can be closed individually by clicking X on the upper right of the Figure or by any of the usual Windows techniques. You can close them all by clicking Close figures in the Imatest main window.

CSV and JSON output files

Individual Imatest modules can optionally write two types of output file that contain most results.

• CSV files are most often displayed with Microsoft Excel.
• JSON files, which contain a single large JSON structure, can be read into programs written in almost any language with a single line of code using functions linked from the JSON website. They can be displayed in any text editor.

Please contact us if you have requests or suggestions about Imatest output. [Notes: These files are not saved in evaluation mode. ]

CSV files– Excel-readable Comma-Separated Variable format. Here is an example of typical output.

Module,Colorcheck
File,Canon_EOS10d_ColorCheck_lt_small.jpg
Run date,31-Dec-2005 18:11:00
Zone,Gray,Pixel,Pixel/255,Px/255 ideal,Log(exp),Log(px/255),WB Err Deg,WB Err Mired
19, 1, 241.6, 0.9475, 0.9569, -0.050, -0.023, 163, -3.8
20, 2, 215.8, 0.8464, 0.7922, -0.230, -0.072, 491, -10.8
21, 3, 179.0, 0.7020, 0.6353, -0.440, -0.154, 450, -10.0

The same data displayed in Excel looks like this.

JSON files are somewhat human-readable text files that contain a single structure— optimized for reading into programs written in virtually any programming language.

{
      "jstruct": {
            "dateRun": "03-May-2018 12:14:03",
            "ini_time_size": "03-May-2018 12:02:35 104121B  MD5 = 6a03a447754eefcc2ada6698ec63d30e",
            "version": "Imatest 5.1.0. ALPHA  Colorcheck",
            "build": "NOT COMPILED",
            "full_path_name": "C:\\imatest\\Data\\Colorcheck\\Canon_eos10d_ColorCheck_lt.jpg",
            "file_name": "Canon_eos10d_ColorCheck_lt.jpg",
            "mean_cameraSat_Pct": [0.9888],
            "pxlLevel_graypatch": [241.67,215.9,179.27,135.26,84.58,34.63],
            "pxlLevel_norml_graypatch": [0.9477,0.8467,0.703,0.5304,0.3317,0.1358],
            "densityNominal": [0.949,0.7882,0.6314,0.4784,0.3255,0.1922],
            "logExposure": [-0.05,-0.23,-0.44,-0.7,-1.05,-1.5],
            "logNormlPxlLevel": [-0.023,-0.072,-0.153,-0.275,-0.479,-0.867],
            "whiteBalErrDegs": [157.3,478,487.1,833.4,954.2,568.3],
...
            "Mean_Delta_E_00": [5.31],
            "Max_Delta_E_00": [11.42],
            "Sigma_Delta_E_00": [5.76],
            "Mean_Delta_C_00": [3.05],
            "Mean_White_Balance_delta_C_00": [2.87],
            "Max_Delta_C_00": [7.52],
            "Sigma_Delta_C_00": [3.45],
            "Mean_Delta_C_00_Sat_corrected": [3.08],
            "Max_Delta_C_00_Sat_corrected": [7.5],
            "Sigma_Delta_C_00_Sat_corrected": [3.44],
            "passfail": {
                  "ini_time_size": "04-Jul-2017 09:31:58 1734B  MD5 = 1a759325ea50ce2c4bc826dae419feac",
                  "passFailFile": "C:\\imatest\\Data\\ini_files\\passfailtest_1.txt",
                  "started_at": "2018-05-03 12:14:03",
                  "ended_at": "2018-05-03 12:14:20",
                  "runtime": [9.135914449],
                  "INI_read_success": "[colorcheck] NOT FOUND",
                  "all_tests_passed": [1]
            }
      }
}