Cosalient Pattern Generator Lite (includes image ADL measurment tool)

[Guy Kuo]

Cosalient Pattern Generator Lite is a video pattern generator and picture ADL measurement tool for MacOS and Windows. It displays patterns I most often need to do a quick display setup with a HTPC. Parts of it are from the pattern generator used to create AVIA Pro.

This is a "personal use only" treat for fellow HT enthusiasts. No product support from Kuo Software is implied. App is not to be distributed commercially nor used to create derivative products.

64 bit versions are supplied for Windows and MacOS. Decompress the zip for your OS prior to use. You may need to right click the app on MacOS on first launch to open it. On Windows, you may need to give the exe permission to run. Do NOT rename or remove any of the associated directories or library files in the Windows version.

Program is navigated via keyboard commands. <> move to prev/next pattern. ? gets you the help screen.

Also, the ADL tool now shows the RGB value and luma% at mouse position.

MacOS version
http://cosalient.com/picture/jvc/Cosalient%20Pattern%20Generator%20Lite%20MacOS.zip

Windows version
http://cosalient.com/picture/jvc/Cosalient%20Pattern%20Generator%20Lite%20Windows.zip


Keyboard functions are...

? help
f or Esc - toggle full screen
q or x - quit application
<> - next / previous pattern
left or right arrow - next / previous pattern

`1234567890 - window patterns from 0 to 100%. Use <> keys to step by 5% luma.
All windows include three black PLUGE lines at RGB 3, 6, 9 for black level adjustment
100% window has two white PLUGE lines at RGB 249, 252 for contrast adjustment

c - color bars at 75%
h - hatch (yellow, cyan, white) for panel convergence
d - dots (yellow, white) for lens focusing
r - red field
g - green field - for lens focusing looking at pixel gaps
b - blue field
w - white field - for checking uniformity
s - sharpness, resolution, chip chart
p - picture ADL% tool
(s in ADL tool saves image and analysis results to jpeg file)

Drag and drop a JPEG or PNG image onto app to measure Average Display Luminance for the image. ADL% is reported for EOTF's of pure 2.2 gamma, pure 2.4 gamma, and BT.1886 set to emulate dark CRT. Both full frame and black bar omitted figures are calculated. Luma histogram scaling is 10% of full frame pixel population at histogram's top line.

Cosalient Pattern Generator Lite accurately imports JPEG or PNG images. Other image types may have their data altered by OS color profile adjustments by merely opening the file (especially under MacOS)

For best accuracy measuring ADL%, obtain your image directly from a playback software, like VLC or MPC-HC, that can directly extract a frame as PNG. Screen captures may not preserved RGB levels.


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BT.1886 parameters used...

See the ITU example at https://www.itu.int/dms_pubrec/itu-r/rec/bt/R-REC-BT.1886-0-201103-I!!PDF-E.pdf

I have set the EOTF parameters to follow the alternative emulation of a CRT with dark black level.

Vc = 0.35
alpha1 = 2.6
alpha2 = 3.0
beta = 0.0183
k = 1/(1 + beta)^alpha1

'Rec BT1886 alt EOTF to emulate a CRT
if V < Vc then
VgammaEOTF = (k * (Vc + beta)^alpha1minus2) * (V + beta)^alpha2
else
VgammaEOTF = k * (V + beta)^alpha1
end