Reject invalid MPEG puts for certain lib versions #8803
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It seems it started requiring 64k at 1.05.
This mimics behavior with clamped sizes and wrap around, and also makes it easier to implement the garbage data handling the PSP has.
This also parses a bit earlier, not requiring a full 2048 bytes ahead at all times.
Older libraries only, but this will cause it to reject packets that don't make sense. So far, this seems to mirror the behavior of various garbage packets sent to the real firmware.
When we've got garbage data, this has to stay incorrect. Without this, Megaman X gets confused when playing its video (because it enqueues garbage packets.) See hrydgard#3318.
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Are you plan to write UMD video in the future ? |
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Well, it'd probably be more worthwhile to ask FFmpeg to detect and support atrac3plus (which it can already decode) in standard video files. If they did that, most likely UMD videos would be playable in just any video player you wanted, as long as it used ffmpeg. That sounds like a better outcome than PPSSPP having support for it, especially because PPSSPP is a pretty terrible video player. It can't handle subtitles or fonts in the stream, doesn't have fancy scrubbing controls, doesn't support embedded album art, doesn't add latency to video when audio is lagging (which would be a terrible thing for an emulator but is a great thing for a video player), etc. Basically, there are a bunch of really popular video players out there that people have devoted hundreds or even thousands of hours to making great. And they are great. I feel no motivation to throw hundreds of my own hours into making a not-as-great video player. Isn't it better for a great video player to support another video format, rather than a great emulator to try to "me too" being a video player? -[Unknown] |
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Also fixes #6657 |
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Oh, cool. I guess that explains what was happening there. Does it help #8526? -[Unknown] |
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No. |
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@zminhquanz btw, here's the ticket for that: https://trac.ffmpeg.org/ticket/3233 -[Unknown] |
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oh , i'm very pleasure , good job |
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Does it add from #8702 |
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No, that's not related. |
The good news: this reportedly fixes #3318, and fixes #6657.
This change is probably a bit risky, but I've tested a number of games and haven't run into any video problems. I still don't really know what "PMP videos" are and have not tested the specialized code dedicated to them.
Here are the major things this does:
However, one note: I have found two 1.03 mpeg.prx's that have different behavior. Technically, some of this behavior is correct for 1.03a but not for 1.03b. Hoping it doesn't matter, I don't want to go down the route of crcing them for version numbers...
-[Unknown]