From 72915ca8ba66f96717838439ee13cb3f70f9863f Mon Sep 17 00:00:00 2001 From: Limin Wang Date: Mon, 11 Nov 2019 09:05:02 +0800 Subject: avformat/mp3dec: replace SAME_HEADER_MASK with MP3_MASK mp3 header bitstream syntax: header() { syncword 12bits bslsf id 1bit bslsf layer 2bit bslsf protection_bit 1bit bslsf bitrate_index 4bits bslsf sampling_frequency 2bits bslsf padding_bit 1bit bslsf private_bit 1bit bslsf mode 2bits bslsf mode_extension 2bits bslsf copyright 1bit bslsf original/home 1bit bslsf emphasis 2bits bslsf } if the header is masking with MP3_MASK(0xFFFE0CCF), below fields will be cleared: protection_bit, bitrate_index, sampling_freqency, mode with SAME_HEADER_MASK(0xFFFE0C00), extra below fields will be cleared which didn't make sense: mode_extension, copyright, original/home, emphasis As the MP3_MASK is good for same mp3 header masking and is defined in the header, so it's preferable to remove SAME_HEADER_MASK to keep the masking same. Signed-off-by: Limin Wang Signed-off-by: Michael Niedermayer --- libavformat/mp3dec.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c index dd14174..6888c88 100644 --- a/libavformat/mp3dec.c +++ b/libavformat/mp3dec.c @@ -42,8 +42,6 @@ #define XING_TOC_COUNT 100 -#define SAME_HEADER_MASK \ - (0xffe00000 | (3 << 17) | (3 << 10) | (3 << 19)) typedef struct { AVClass *class; @@ -398,7 +396,7 @@ static int mp3_read_header(AVFormatContext *s) ffio_ensure_seekback(s->pb, i + 1024 + frame_size + 4); ret = check(s->pb, off + i + frame_size, &header2); if (ret >= 0 && - (header & SAME_HEADER_MASK) == (header2 & SAME_HEADER_MASK)) + (header & MP3_MASK) == (header2 & MP3_MASK)) { av_log(s, i > 0 ? AV_LOG_INFO : AV_LOG_VERBOSE, "Skipping %d bytes of junk at %"PRId64".\n", i, off); ret = avio_seek(s->pb, off + i, SEEK_SET); -- cgit v1.1