Wanna do some tests without building a test card video completely from scratch myself.
I have at least one BD with A/V sync tests, but I'd rather not have to use 16:9 for testing VHS workflows.
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A lot of THX certified DVDs include test patterns. I don't recall if there are any A/V sync tests. You could use AviSynth to generate ColorBars and overlay a graph of the audio.
ColorBars(width=720, height=576) AssumeFPS(25) AudioGraph(0)
Sadly, no sync tests with THX discs.
ColorBars: I forgot that "The tone pulses in the right speaker, being turned on and off once every second." Thought it was a constant.
So I could overlay the AudioGraph in the burned video, capture it, run AudioGraph on the capture, and visually see any offset, yeah? I suppose Subtract + DelayAudio could be used to determine the number of ms? Assuming levels can be matched relatively closely...
Are there any industry-standard test patterns for automatically determining A/V offset values?
[Attachment 41370 - Click to enlarge]
With a 25 fps video we know that the duration of each frame is 40 ms. You can see the audio change amplitude at about 1/4 the width of the frame, 40 * 1/4 = 10.