diff options
Diffstat (limited to 'libavcodec/ac3_parser.c')
-rw-r--r-- | libavcodec/ac3_parser.c | 20 |
1 files changed, 16 insertions, 4 deletions
diff --git a/libavcodec/ac3_parser.c b/libavcodec/ac3_parser.c index 17f205bfd2..14ca196aaf 100644 --- a/libavcodec/ac3_parser.c +++ b/libavcodec/ac3_parser.c @@ -34,6 +34,18 @@ static const uint8_t eac3_blocks[4] = { 1, 2, 3, 6 }; +/** + * Table for center mix levels + * reference: Section 5.4.2.4 cmixlev + */ +static const uint8_t center_levels[4] = { 4, 5, 6, 5 }; + +/** + * Table for surround mix levels + * reference: Section 5.4.2.5 surmixlev + */ +static const uint8_t surround_levels[4] = { 4, 6, 7, 6 }; + int avpriv_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr) { @@ -53,8 +65,8 @@ int avpriv_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr) hdr->num_blocks = 6; /* set default mix levels */ - hdr->center_mix_level = 1; // -4.5dB - hdr->surround_mix_level = 1; // -6.0dB + hdr->center_mix_level = 5; // -4.5dB + hdr->surround_mix_level = 6; // -6.0dB if(hdr->bitstream_id <= 10) { /* Normal AC-3 */ @@ -76,9 +88,9 @@ int avpriv_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr) skip_bits(gbc, 2); // skip dsurmod } else { if((hdr->channel_mode & 1) && hdr->channel_mode != AC3_CHMODE_MONO) - hdr->center_mix_level = get_bits(gbc, 2); + hdr-> center_mix_level = center_levels[get_bits(gbc, 2)]; if(hdr->channel_mode & 4) - hdr->surround_mix_level = get_bits(gbc, 2); + hdr->surround_mix_level = surround_levels[get_bits(gbc, 2)]; } hdr->lfe_on = get_bits1(gbc); |