BACKENDS: 3DS: BLADERUNNER: Slightly slow video elements (cutscenes, menu animations, etc)

[BallM4788]

Platform: New Nintendo 3DS
ScummVM version: commit ​78ec256
Description: Whenever a video element such as a cutscene or a menu animation plays, it does so at a slightly slower speed than it should. This causes it to become progressively more out of sync with its accompanying audio, which plays at the proper speed. I'm not sure whether this holds true in normal gameplay as well; if it does, it's not as noticeable.
Reproduction: Trigger any cutscene or menu animation. The easiest way is to start a new game. The problem is especially visible in the opening cutscene; by the time the scene reaches the Runciter's Animals segment, the video is ~1 second out of sync with the audio as evidenced by characters' lip movements.

[antoniou79]

Could you try this with a developer build after this recent patch?
​https://github.com/scummvm/scummvm/commit/772a38588c6712fdd89076ad49b0d03bacdaca18

I don't expect it will resolve the issue entirely, since the patch does not speed up the video decoder, but it should try to keep audio and video synched. So this could lead to audio glitches, while the audio waits for the video to catch up.

I'm still interested on the resulting behavior though, if you could check.

[BallM4788]

Just finished trying it out. Yeah there are definitely some audio glitches that last fractions of a second each, but it's not enough to by annoying or unbearable. As far as when the glitches occur in cutscenes, it seems to be when there's a lot of drastically changing colors on screen. Some examples in the opening cutscene:

• the fire spurts in the LA flyover
• the dramaic camera sweep to the Runciter's Animals exterior
• some of the character closeups
• McCoy waking up in his Spinner

No audio glitches in-game from what I tried out. It seems like character animation in-game MIGHT be be a smidgen laggy in this build, but it's such a small amount it might just be me seeing things.

Thinking back on it, there was this same issue (slow video) on 3DS with Riven around a year or so ago, though I can't remember what was done to fix it. Might want to ask Bastien (bgK), since he's pretty much the go-to guy for Mohawk (the Myst/Riven engine) stuff.

[antoniou79]

Aside from the new audio glitches, does the video still become desynched with the audio for you after the recent commit?

[BallM4788]

Aside from the audio glitches no, everything's synced up.

[antoniou79]

Nice, good to know. And thank you for the detailed feedback!
I'll leave this ticket open, since I want to review the decoder code for any possible optimizations.