AnyPS5/docs/dev/debt/libSceOpusDec.md

libSceOpusDec technical debt

Unknown function info

• sceOpusDecCancel, sceOpusDecCreate, sceOpusDecCtl, sceOpusDecDecodeFloat, sceOpusDecDecodeFloatWithPriority, sceOpusDecDecodeFloatWithPriorityAndTimeout, sceOpusDecDecodeWithPriority and sceOpusDecDecodeWithPriorityAndTimeout (libSceOpusDec) - names and NIDs are present in the PS5 3.20 export inventory, but no credible prototypes were found. They are declared without parameters solely to resolve known imports; this is not an ABI claim.

Functional

• libSceOpusDec uses FFmpeg for mono/stereo signed-16 decoding at the creation rates the research lists: 8000, 12000, 16000, 24000 and 48000 Hz. The supplied module confirms the exported arguments, read-only context inputs, 640-byte state size and creation rates. Validation errors and their precedence are recovered. Console PCM equivalence, AJM failures, context ownership and termination with live decoders remain unimplemented. Packet loss concealment still throws; decoder state is kept in host registries instead of the native guest state layout.
• sceOpusDecDecode (libSceOpusDec) returns exactly the packet's duration, as libopus does. FFmpeg resamples narrowband SILK from 8 kHz and holds back 24 samples of the first narrowband packet after the decoder starts or after a packet of another bandwidth, releasing them with the next packet that is not narrowband. The decoder keeps FFmpeg's output in order and pads the start with silence, so such a packet begins with 24 samples (0.5 ms) of silence and the output after it is 24 samples late; libopus has no such gap
• sceOpusDecDecode (libSceOpusDec, libSceOpusCeltDec) decodes at 48000 Hz and converts to a lower creation rate with FFmpeg's resampler, where libopus decodes at that rate directly. The resampler's filter delay is padded with silence at the start of the stream like the narrowband delay above, so the output is late by that delay and is not sample-identical to libopus; which of the two the console matches is not measured