TS: Increment PMT version when codecs change for strict demuxers. v8.0.30 - #4731
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The PMT was always written with version_number=0. On HTTP-TS, when AAC audio appears after the initial video-only PMT, strict demuxers such as libVLC ignored the re-announced PMT (same version) and reported "Audio packets for PID 257 arrive but have no PMT entry", dropping the audio. Bump the PMT version_number modulo 32 each time encode_pat_pmt() is invoked due to a codec change, as required by ISO/IEC 13818-1 2.6.4. The PAT is left unchanged because its program-to-PMT-PID mapping never changes, and the version resets to 0 on SrsTsContext::reset() so each HLS segment starts fresh. Add KernelTSTest.PmtVersionIncrementsOnCodecChange which drives the real HTTP-TS codec-discovery ordering and asserts the on-wire PMT versions are [0, 1], and [0] after reset. Co-Authored-By: Claude <noreply@anthropic.com>
Update SRS 8.0 revision to v8.0.29 in both C++ and Go version files, and add the changelog entry for PR ossrs#4731. --------- Co-authored-by: chatgpt-codex-connector[bot] <199175422+chatgpt-codex-connector[bot]@users.noreply.github.com>
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Fix HTTP-TS playback with strict MPEG-TS demuxers, such as MobileVLCKit/libVLC on iOS, by incrementing the PMT
version_numberwhenever SRS refreshes the PMT after a codec-set change.Problem
For HTTP-TS, SRS may start with unknown audio/video codecs when
guess_has_avis enabled. If the first media packet is video, SRS emits an initial PMT that describes only the video PID. When AAC audio is discovered later, SRS emits another PMT that adds the AAC PID0x101.Before this fix, every PMT used
version_number = 0. Strict demuxers can treat a same-version PMT as unchanged, ignore the refreshed PMT, and then drop AAC packets because PID257 / 0x101was never registered. The visible symptom is video playback without audio for HTTP-TS on iOS libVLC.Root cause
SrsTsPacket::create_pmt()hardcoded the PMT version to zero, whileSrsTsContext::encode()already refreshes PAT/PMT when the codec set changes. The PMT content changes, but the PMT version does not, so strict receivers may reject the update.