From 8ce32a7cbb17e47e4e7f8a278c5b05cd9e6e967e Mon Sep 17 00:00:00 2001 From: xiongweixiao Date: Mon, 12 May 2025 07:36:35 +0800 Subject: [PATCH] lavf: vvc_probe: lower probe score for invalid SPS/PPS/IRAP order to avoid misdetection of mp3 as VVC The current vvc_probe function checks for SPS, PPS, and IRAP NAL units but does not enforce their detection order. This can lead to false positives when PPS or IRAP appear before SPS, causing malformed or non-compliant bitstreams to be incorrectly identified as valid VVC streams. This commit modifies the logic to use boolean flags and enforces the correct detection sequence: SPS must be detected before PPS, and PPS before IRAP. This ensures more accurate probing and prevents invalid bitstreams from being misidentified. For streams with wrong ordering a lower score is returned This change addresses issues reported in: - https://trac.ffmpeg.org/ticket/11496 - https://trac.ffmpeg.org/ticket/11087 Signed-off-by: xiongweixiao Signed-off-by: Michael Niedermayer --- libavformat/vvcdec.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/libavformat/vvcdec.c b/libavformat/vvcdec.c index 0a0e24b71c..1bfa1b5d69 100644 --- a/libavformat/vvcdec.c +++ b/libavformat/vvcdec.c @@ -44,6 +44,7 @@ static int vvc_probe(const AVProbeData *p) { uint32_t code = -1; int sps = 0, pps = 0, irap = 0; + int valid_pps = 0, valid_irap = 0; int i; for (i = 0; i < p->buf_size - 1; i++) { @@ -60,17 +61,29 @@ static int vvc_probe(const AVProbeData *p) switch (type) { case VVC_SPS_NUT: sps++; break; - case VVC_PPS_NUT: pps++; break; + case VVC_PPS_NUT: + pps++; + if (sps) + valid_pps++; + break; case VVC_IDR_N_LP: case VVC_IDR_W_RADL: case VVC_CRA_NUT: - case VVC_GDR_NUT: irap++; break; + case VVC_GDR_NUT: + irap++; + if (valid_pps) + valid_irap++; + break; } } } - if (sps && pps && irap) + if (valid_irap) return AVPROBE_SCORE_EXTENSION + 1; // 1 more than .mpg + if (sps && pps && irap) + return AVPROBE_SCORE_EXTENSION / 2; + if (sps || pps || irap) + return AVPROBE_SCORE_EXTENSION / 4; return 0; }