uint16_t frame_size;
int center_mix_level; ///< Center mix level index
int surround_mix_level; ///< Surround mix level index
+ uint16_t channel_map;
/** @} */
} AC3HeaderInfo;
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)
{
*/
int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr);
+/**
+ * Parses AC-3 frame header and sets channel_map
+ * Parses the header up to the lfeon (channel_map in E-AC-3)
+ * element, which is the first 52, 54 or 104 bits depending
+ * on the audio coding mode.
+ * @param gbc[in] BitContext containing the first 54 bits of the frame.
+ * @param hdr[out] Pointer to struct where header info is written.
+ * @return value returned by ff_ac3_parse_header
+ */
+int ff_ac3_parse_header_full(GetBitContext *gbc, AC3HeaderInfo *hdr);
+
#endif /* FFMPEG_AC3_PARSER_H */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 3, 3, 3, 3,
3, 6, 6, 6, 6, 6, 6, 12, 12, 12, 12, 24, 24, 24, 24, 24
};
+/**
+ * Default channel map for a dependent substream defined by acmod
+ */
+const uint16_t ff_eac3_default_chmap[8] = {
+ AC3_CHMAP_L | AC3_CHMAP_R, // FIXME Ch1+Ch2
+ AC3_CHMAP_C,
+ AC3_CHMAP_L | AC3_CHMAP_R,
+ AC3_CHMAP_L | AC3_CHMAP_C | AC3_CHMAP_R,
+ AC3_CHMAP_L | AC3_CHMAP_R | AC3_CHMAP_C_SUR,
+ AC3_CHMAP_L | AC3_CHMAP_C | AC3_CHMAP_R | AC3_CHMAP_C_SUR,
+ AC3_CHMAP_L | AC3_CHMAP_R | AC3_CHMAP_L_SUR | AC3_CHMAP_R_SUR,
+ AC3_CHMAP_L | AC3_CHMAP_C | AC3_CHMAP_R | AC3_CHMAP_L_SUR | AC3_CHMAP_R_SUR
+};
extern const int16_t ff_ac3_floor_tab[8];
extern const uint16_t ff_ac3_fast_gain_tab[8];
extern const uint8_t ff_ac3_critical_band_size_tab[50];
+extern const uint16_t ff_eac3_default_chmap[8];
+
+/** Custom channel map locations bitmask
+ * Other channels described in documentation:
+ * Lc/Rc pair, Lrs/Rrs pair, Ts, Lsd/Rsd pair,
+ * Lw/Rw pair, Lvh/Rvh pair, Cvh, Reserved, LFE2
+ */
+enum CustomChannelMapLocation{
+ AC3_CHMAP_L= 1<<(15-0),
+ AC3_CHMAP_C= 1<<(15-1),
+ AC3_CHMAP_R= 1<<(15-2),
+ AC3_CHMAP_L_SUR= 1<<(15-3),
+ AC3_CHMAP_R_SUR = 1<<(15-4),
+ AC3_CHMAP_C_SUR= 1<<(15-7),
+ AC3_CHMAP_LFE = 1<<(15-15)
+};
#endif /* FFMPEG_AC3TAB_H */