[FFmpeg-devel] [PATCH] avcodec/mpegaudiodec_template: disable CRC checking for layers 1 and 2

James Almer jamrial at gmail.com
Mon Aug 3 16:43:11 EEST 2020


Layers 1 and 2 use lengths in bits which are not a multiple of 8,
and our CRC works on a per-byte basis.

Based on b48397e7b8

Signed-off-by: James Almer <jamrial at gmail.com>
---
 libavcodec/mpegaudiodec_template.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/mpegaudiodec_template.c b/libavcodec/mpegaudiodec_template.c
index 3d7e3ba4f2..3ae73d3c8d 100644
--- a/libavcodec/mpegaudiodec_template.c
+++ b/libavcodec/mpegaudiodec_template.c
@@ -1568,7 +1568,7 @@ static int mp_decode_frame(MPADecodeContext *s, OUT_INT **samples,
 
     if (s->error_protection) {
         uint16_t crc = get_bits(&s->gb, 16);
-        if (s->err_recognition & AV_EF_CRCCHECK) {
+        if (s->err_recognition & AV_EF_CRCCHECK && s->layer == 3) {
             const int sec_len = s->lsf ? ((s->nb_channels == 1) ? 9  : 17) :
                                          ((s->nb_channels == 1) ? 17 : 32);
             const AVCRC *crc_tab = av_crc_get_table(AV_CRC_16_ANSI);
-- 
2.27.0



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