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oyvindln / vhs-decode

Software defined VHS decoder - Fork (maybe temporary) of the ld-decode Laserdisc rf decoder
GNU General Public License v3.0
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Sync locking fails on 240p/288p type signals and other non-standard vblank #19

Open oyvindln opened 3 years ago

oyvindln commented 3 years ago

Issue for both cvbs-decode and vhs-decode.

oyvindln commented 2 years ago

Current code only looks for a standards-conforming line of eq/vsync/eq pulses. Dropons on a field is usually okay due to guessing based on previous vsync, but we get issues with samples where the vblank area is abnormal like "240p/288p" type signals.

Maybe a first fallback could be to do something based on pulses longer than some set length since it will have to be present in some form for a CRT to display it.

oyvindln commented 1 year ago

--fallback_vsync option does this for vhs-decode now. Causes some sync issues on the crafters sample that at least needs to be figured out before making it standard.