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Fix FF decode by miniMax AI

Open sum2012 opened this issue 1 month ago • 3 comments

by https://agent.minimax.io/share/334835562430541?chat_type=1 fix #15203

original bad log (v1.19.3-1105-g636e5b33b6) v1.19.3-1105-g636e5b33b6-bad-ppsspplog.txt.zip Modify good log: fixed-ppsspplog.zip

The data at offset 2048 shows: 008800 00 00 01 ba 44 00 05 86 d5 c3 01 86 a3 f8 00 00 The pattern 00 00 01 ba is the MPEG-2 transport stream sync marker! This means the video data after the 2048-byte PSMF header is in MPEG-TS format.

sum2012 avatar Nov 16 '25 14:11 sum2012

Hmm.. I saw that the AI is mentioning "sync marker bytes 00 00 01 ba" at the end.

But according to this (page 7) https://ossrs.net/lts/zh-cn/assets/files/hls-mpeg-ts-VB_WhitePaper_TransportStreamVSProgramStream_rd2-54391b430dd4df50a827467e80854828.pdf

The first byte (Sync Byte) in MPEG-TS header supposed to be 0x47 🤔 which matched the answer at https://stackoverflow.com/questions/35974281/mpeg2-ts-sync-byte-and-continuity-error

anr2me avatar Nov 16 '25 16:11 anr2me

Hmm.. I saw that the AI is mentioning "sync marker bytes" at the end.

But according to this (page 7) https://ossrs.net/lts/zh-cn/assets/files/hls-mpeg-ts-VB_WhitePaper_TransportStreamVSProgramStream_rd2-54391b430dd4df50a827467e80854828.pdf

The first byte (Sync Byte) in MPEG-TS header supposed to be 0x47 🤔 which matched the answer at https://stackoverflow.com/questions/35974281/mpeg2-ts-sync-byte-and-continuity-error

MPEG-TS header check is in here https://github.com/hrydgard/ppsspp/pull/21012/files#diff-72f58d004beb4c29fe682970ebc40289bfd08d1ddbbf8cdd450a8338ac925d07R493

sum2012 avatar Nov 16 '25 21:11 sum2012

Interesting, will look at this soon.

hrydgard avatar Nov 22 '25 15:11 hrydgard