/*
- * AC3 parser
+ * AC-3 parser
* Copyright (c) 2003 Fabrice Bellard.
* Copyright (c) 2003 Michael Niedermayer.
*
1, 2, 3, 6
};
-/**
- * Table for center mix levels
- * reference: Section 5.4.2.4 cmixlev
- */
-static const uint8_t center_levels[4] = { 2, 3, 4, 3 };
-
-/**
- * Table for surround mix levels
- * reference: Section 5.4.2.5 surmixlev
- */
-static const uint8_t surround_levels[4] = { 2, 4, 0, 4 };
-
int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
{
int frame_size_code;
- int num_blocks;
memset(hdr, 0, sizeof(*hdr));
if(hdr->bitstream_id > 16)
return AC3_PARSE_ERROR_BSID;
+ hdr->num_blocks = 6;
+
+ /* set default mix levels */
+ hdr->center_mix_level = 1; // -4.5dB
+ hdr->surround_mix_level = 1; // -6.0dB
+
if(hdr->bitstream_id <= 10) {
/* Normal AC-3 */
hdr->crc1 = get_bits(gbc, 16);
skip_bits(gbc, 3); // skip bitstream mode
hdr->channel_mode = get_bits(gbc, 3);
- /* set default mix levels */
- hdr->center_mix_level = 3; // -4.5dB
- hdr->surround_mix_level = 4; // -6.0dB
-
if(hdr->channel_mode == AC3_CHMODE_STEREO) {
skip_bits(gbc, 2); // skip dsurmod
} else {
if((hdr->channel_mode & 1) && hdr->channel_mode != AC3_CHMODE_MONO)
- hdr->center_mix_level = center_levels[get_bits(gbc, 2)];
+ hdr->center_mix_level = get_bits(gbc, 2);
if(hdr->channel_mode & 4)
- hdr->surround_mix_level = surround_levels[get_bits(gbc, 2)];
+ hdr->surround_mix_level = get_bits(gbc, 2);
}
hdr->lfe_on = get_bits1(gbc);
hdr->channels = ff_ac3_channels_tab[hdr->channel_mode] + hdr->lfe_on;
hdr->frame_size = ff_ac3_frame_size_tab[frame_size_code][hdr->sr_code] * 2;
hdr->frame_type = EAC3_FRAME_TYPE_AC3_CONVERT; //EAC3_FRAME_TYPE_INDEPENDENT;
+ hdr->substreamid = 0;
} else {
/* Enhanced AC-3 */
hdr->crc1 = 0;
if(hdr->frame_type == EAC3_FRAME_TYPE_RESERVED)
return AC3_PARSE_ERROR_FRAME_TYPE;
- skip_bits(gbc, 3); // skip substream id
+ hdr->substreamid = get_bits(gbc, 3);
hdr->frame_size = (get_bits(gbc, 11) + 1) << 1;
if(hdr->frame_size < AC3_HEADER_SIZE)
return AC3_PARSE_ERROR_SAMPLE_RATE;
hdr->sample_rate = ff_ac3_sample_rate_tab[sr_code2] / 2;
hdr->sr_shift = 1;
- num_blocks = 6;
} else {
- num_blocks = eac3_blocks[get_bits(gbc, 2)];
+ hdr->num_blocks = eac3_blocks[get_bits(gbc, 2)];
hdr->sample_rate = ff_ac3_sample_rate_tab[hdr->sr_code];
hdr->sr_shift = 0;
}
hdr->lfe_on = get_bits1(gbc);
hdr->bit_rate = (uint32_t)(8.0 * hdr->frame_size * hdr->sample_rate /
- (num_blocks * 256.0));
+ (hdr->num_blocks * 256.0));
hdr->channels = ff_ac3_channels_tab[hdr->channel_mode] + hdr->lfe_on;
}
return 0;
}
+int ff_ac3_parse_header_full(GetBitContext *gbc, AC3HeaderInfo *hdr){
+ int ret, i;
+ ret = ff_ac3_parse_header(gbc, hdr);
+ if(!ret){
+ if(hdr->bitstream_id>10){
+ /* Enhanced AC-3 */
+ skip_bits(gbc, 5); // skip bitstream id
+
+ /* skip dialog normalization and compression gain */
+ for (i = 0; i < (hdr->channel_mode ? 1 : 2); i++) {
+ skip_bits(gbc, 5); // skip dialog normalization
+ if (get_bits1(gbc)) {
+ skip_bits(gbc, 8); //skip Compression gain word
+ }
+ }
+ /* dependent stream channel map */
+ if (hdr->frame_type == EAC3_FRAME_TYPE_DEPENDENT && get_bits1(gbc)) {
+ hdr->channel_map = get_bits(gbc, 16); //custom channel map
+ return 0;
+ }
+ }
+ //default channel map based on acmod and lfeon
+ hdr->channel_map = ff_eac3_default_chmap[hdr->channel_mode];
+ if(hdr->lfe_on)
+ hdr->channel_map |= AC3_CHMAP_LFE;
+ }
+ return ret;
+}
+
static int ac3_sync(uint64_t state, AACAC3ParseContext *hdr_info,
int *need_next_header, int *new_frame_start)
{
AVCodecParser ac3_parser = {
- { CODEC_ID_AC3 },
+ { CODEC_ID_AC3, CODEC_ID_EAC3 },
sizeof(AACAC3ParseContext),
ac3_parse_init,
ff_aac_ac3_parse,
- NULL,
+ ff_parse_close,
};