piLagTesterPRO version 2.4 released!

I just uploaded version 2.4 of the piLagTesterPRO release for pi0 and pi4 users. 

A few interesting changes in this release:

The pi4 version now has proper handing of display overscan (the annoying trait of TVs to crop off the edges of the video signal). Overscan compensation is enabled in text mode only (basically, putting a border around the text). When testing lag, however, those borders are removed and the entire screen is used. 

A new command line option has been added which uses wide test probe bars that span the entire width of the screen. This is useful for testing a display that is not showing a complete image (such as due to a cracked LCD panel). 

A new utility script has been added called "autoTest", which takes a single argument: the number of samples to record before calculating the average lag. This then tests the entire set of resolutions/refresh rates specified in the script with zero interaction required from the user. Very handy for checking if the input lag has changed after a firmware update or a configuration change. 

I've also added a small test image to the lower corner of the screen where the real-time input lag graph is. This serves as a quick and handy way to check how well the TV is upscaling/downscaling the input to the TV's native resolution, and how this interacts with the zoom/scaling/aspect ratio/overscan options of the TV.

Below, left, is an actual screen capture of the image from a Panasonic plasma TV. And, to the right, the full test image as it should appear on a pixel perfect display with no cropping at native resolution. 



This single image isn't perfect, but it does combine all the major things I care about: cropping, aliasing, and over sharpening/ringing in a single 160 pixel wide image. But the best thing about making a Lag Tester that runs a full Linux OS is that this test image can easily be replaced with any PNG file you wish. I recommend a small one, though, so it doesn't interfere with the visibility of the input lag plot.

Last but far from least, this is the first piLagTesterPRO release where 4k support is fully tested and verified against published values by RTINGS on a couple different TVs. This is such a significant "news" item that I'll do a full post just about it later. 

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