# libSceAvPlayer technical debt

### Silent stubs

- [libSceAvPlayer](../../../core/libs/prx/libSceAvPlayer/Export.cpp): `sceAvPlayerSetLogCallback` accepts a callback that is never called, as the player produces no log messages, and `sceAvPlayerSetAvailableBandwidth` has no effect, as it governs HLS sources, which `sceAvPlayerAddSource` does not implement; after a source is added it returns `OPERATION_FAILED`, as [prosper's reading of the module](https://github.com/mattias800/prosper/blob/8dcb5dfdb9997ede7c76783995010d6abd1222f8/prosper/src/hle/video/avplayer.cpp#L960-L972) describes.
- [sceAvPlayerSetTrickSpeed](../../../core/libs/prx/libSceAvPlayer/src/Source.cpp) (libSceAvPlayer) with a negative speed runs the clock backwards but delivers no frames; when a forward speed is set again, playback resumes from the rewound time. With a source, a zero speed returns `INVALID_PARAMS` before the `OPERATION_FAILED` of a stopped, finished or failed player, the order AnyPS5 had before; that order is unmeasured. In [prosper's reading of the module](https://github.com/mattias800/prosper/blob/8dcb5dfdb9997ede7c76783995010d6abd1222f8/prosper/src/hle/video/avplayer.cpp#L929-L959), only the missing source is checked first. A zero speed is refused with `NOT_SUPPORTED`, with every other speed from -399 to 399 except 100, and no player state is checked.

### Unknown function info

- [AvPlayer loop warnings](../../../core/libs/prx/libSceAvPlayer/src/Source.cpp) are queued when the first audio or video frame of a loop is delivered, following [KytyPS5's playback boundary tracking](https://github.com/KytyPS5/KytyPS5/blob/a6f4e8e7f456b8697d3102823d3f16400c3e121e/src/libs/avPlayer.cpp#L1038-L1043). The console's exact callback timing is unverified. Decode-ahead does not announce a loop while the caller is consuming the previous pass.

- [sceAvPlayerAddSource](../../../core/libs/prx/libSceAvPlayer/src/Source.cpp) (libSceAvPlayer) - requests up to 4 additional decode-ahead video framebuffers from the memory replacement beyond `num_output_video_framebuffers` when memory is available; the console's internal buffering behaviour is unknown
- [sceAvPlayerInit / sceAvPlayerInitEx](../../../core/libs/prx/libSceAvPlayer/src/Player.cpp) (libSceAvPlayer) - behaviour without a memory replacement unknown; frame and sample buffers then come from the guest heap
- [sceAvPlayerInitEx](../../../core/libs/prx/libSceAvPlayer/Export.cpp) (libSceAvPlayer) - the PS5 init data layout (`this_size` 0x230: auto start at 0x74, nine 0x30-byte thread parameter blocks from 0x78, output video frame buffer count at 0x228) follows [KytyPS5](https://github.com/KytyPS5/KytyPS5/blob/main/src/libs/avPlayer.cpp), [prosper](https://github.com/mattias800/prosper/blob/main/prosper/src/hle/video/avplayer.cpp), [SharpProspero](https://github.com/SvenGDK/SharpProspero/blob/main/src/SharpProspero/Interop/Media/AvPlayer.cs) and [sharpemu](https://github.com/sharpemu/sharpemu/blob/main/src/SharpEmu.Libs/AvPlayer/AvPlayerExports.cs), which agree on it. PPSA25063 fills the same fields, writes auto start 0 and starts playback with `sceAvPlayerStart`; a title that sets auto start has not been seen. A smaller `this_size` is read with the PS4 offsets. The thread parameters are ignored
- [AvPlayer auto start](../../../core/libs/prx/libSceAvPlayer/src/Player.cpp) (libSceAvPlayer) - the auto start that `sceAvPlayerAddSource` queues for a player with auto start or without an event callback starts the player only while it is still ready: a title that starts the player itself before the auto start runs keeps its playback and the frames it holds. Not confirmed on a title.

- [Paused initial video](../../../core/libs/prx/libSceAvPlayer/src/Source.cpp) (libSceAvPlayer) keeps the first picture available when audio has already established the playback epoch before the caller pauses. Further pictures of that epoch stay blocked, as after a paused jump. The console's exact initial preparation ordering has not been measured.

### Functional

- [sceAvPlayerGetVideoData / sceAvPlayerGetVideoDataEx](../../../core/libs/prx/libSceAvPlayer/src/Source.cpp) (libSceAvPlayer) - delivers a video frame up to 0.75 × frame duration ahead of its timestamp in default sync mode to accommodate presentation loops that poll slightly before the refresh boundary; the console's exact presentation tolerance is unverified.
- [sceAvPlayerGetVideoData](../../../core/libs/prx/libSceAvPlayer/src/Source.cpp) (libSceAvPlayer) in sync mode `SCE_AVPLAYER_AV_SYNC_MODE_NONE` skips queued frames that the audio clock has already passed while the title pulls audio, so a title that requests video slower than the film's frame rate keeps the picture with the sound. Whether the console hands out every frame in this mode is unknown. PPSA12544 requests 7-19 frames per second for a 30 fps cinematic