m35 / jpsxdec

jPSXdec: cross-platform PlayStation 1 audio and video converter
http://jpsxdec.blogspot.com/
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Frame rate is displayed incorrectly #76

Open jooqw opened 1 year ago

jooqw commented 1 year ago

Environment

jPSXdec version: 1.06 beta Operating system: Win11 Java runtime environment : 1.8.0_381

PlayStation Game (if applicable)

Name: Um Jammer Lammy Region code (e.g. SLUS-1234): SCUS_944.48

Description

What were you doing?: Checking videos

What happened?: Frame rate was displayed incorrectly in 1.06 beta but it was normal on 1.0 image here is on 1.0 image

What was or was not supposed to happen?: not supposed to happen

m35 commented 1 year ago

Unfortunately Um Jammer Lammy has been particularly troublesome because several of its videos have variable frame rates. Neither jPSXdec v1.00 nor v1.06 actually have the correct frame rate because the video doesn't really have one.

I haven't tested it lately, but I think v1.00 will use the 7.039 fps, but the video frame timings will drift and play sooner or later than what you would see in game. v1.06 tried to improve the situation by increasing the frame rate, then repeating frames until the correct time to show the next frame. Definitely not ideal, but it's the best we can do with the AVI format.

I'd like to change from the AVI format to MKV because MKV supports variable frame rates. But there's no timeline on when that will be available.