diff options
author | Aurelien Jacobs <aurel@gnuage.org> | 2007-05-09 03:25:31 +0400 |
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committer | Aurelien Jacobs <aurel@gnuage.org> | 2007-05-09 03:25:31 +0400 |
commit | 99ff31dc750e8ac562b529c3ec374cfbb3e66157 (patch) | |
tree | 61c8496a4d314d0b05942559ec49400f1258d5b5 /libavcodec/parser.c | |
parent | e0fe500f01ebd7c1b129674213845a48ec46008c (diff) |
move aac and ac3 parsers in their own files
Originally committed as revision 8941 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/parser.c')
-rw-r--r-- | libavcodec/parser.c | 298 |
1 files changed, 0 insertions, 298 deletions
diff --git a/libavcodec/parser.c b/libavcodec/parser.c index 9b1e792e26..482ace298a 100644 --- a/libavcodec/parser.c +++ b/libavcodec/parser.c @@ -311,301 +311,3 @@ int ff_mpeg4video_split(AVCodecContext *avctx, } return 0; } - -/*************************/ - -#if defined(CONFIG_AC3_PARSER) || defined(CONFIG_AAC_PARSER) -/* also used for ADTS AAC */ -typedef struct AC3ParseContext { - uint8_t *inbuf_ptr; - int frame_size; - int header_size; - int (*sync)(const uint8_t *buf, int *channels, int *sample_rate, - int *bit_rate, int *samples); - uint8_t inbuf[8192]; /* input buffer */ -} AC3ParseContext; - -#define AC3_HEADER_SIZE 7 -#define AAC_HEADER_SIZE 7 - -#ifdef CONFIG_AC3_PARSER - -static const uint8_t eac3_blocks[4] = { - 1, 2, 3, 6 -}; - -#endif /* CONFIG_AC3_PARSER */ - -#ifdef CONFIG_AAC_PARSER -static const int aac_sample_rates[16] = { - 96000, 88200, 64000, 48000, 44100, 32000, - 24000, 22050, 16000, 12000, 11025, 8000, 7350 -}; - -static const int aac_channels[8] = { - 0, 1, 2, 3, 4, 5, 6, 8 -}; -#endif - -#ifdef CONFIG_AC3_PARSER -int ff_ac3_parse_header(const uint8_t buf[7], AC3HeaderInfo *hdr) -{ - GetBitContext gbc; - - memset(hdr, 0, sizeof(*hdr)); - - init_get_bits(&gbc, buf, 54); - - hdr->sync_word = get_bits(&gbc, 16); - if(hdr->sync_word != 0x0B77) - return -1; - - /* read ahead to bsid to make sure this is AC-3, not E-AC-3 */ - hdr->bsid = show_bits_long(&gbc, 29) & 0x1F; - if(hdr->bsid > 10) - return -2; - - hdr->crc1 = get_bits(&gbc, 16); - hdr->fscod = get_bits(&gbc, 2); - if(hdr->fscod == 3) - return -3; - - hdr->frmsizecod = get_bits(&gbc, 6); - if(hdr->frmsizecod > 37) - return -4; - - skip_bits(&gbc, 5); // skip bsid, already got it - - hdr->bsmod = get_bits(&gbc, 3); - hdr->acmod = get_bits(&gbc, 3); - if((hdr->acmod & 1) && hdr->acmod != 1) { - hdr->cmixlev = get_bits(&gbc, 2); - } - if(hdr->acmod & 4) { - hdr->surmixlev = get_bits(&gbc, 2); - } - if(hdr->acmod == 2) { - hdr->dsurmod = get_bits(&gbc, 2); - } - hdr->lfeon = get_bits1(&gbc); - - hdr->halfratecod = FFMAX(hdr->bsid, 8) - 8; - hdr->sample_rate = ff_ac3_freqs[hdr->fscod] >> hdr->halfratecod; - hdr->bit_rate = (ff_ac3_bitratetab[hdr->frmsizecod>>1] * 1000) >> hdr->halfratecod; - hdr->channels = ff_ac3_channels[hdr->acmod] + hdr->lfeon; - hdr->frame_size = ff_ac3_frame_sizes[hdr->frmsizecod][hdr->fscod] * 2; - - return 0; -} - -static int ac3_sync(const uint8_t *buf, int *channels, int *sample_rate, - int *bit_rate, int *samples) -{ - int err; - unsigned int fscod, acmod, bsid, lfeon; - unsigned int strmtyp, substreamid, frmsiz, fscod2, numblkscod; - GetBitContext bits; - AC3HeaderInfo hdr; - - err = ff_ac3_parse_header(buf, &hdr); - - if(err < 0 && err != -2) - return 0; - - bsid = hdr.bsid; - if(bsid <= 10) { /* Normal AC-3 */ - *sample_rate = hdr.sample_rate; - *bit_rate = hdr.bit_rate; - *channels = hdr.channels; - *samples = AC3_FRAME_SIZE; - return hdr.frame_size; - } else if (bsid > 10 && bsid <= 16) { /* Enhanced AC-3 */ - init_get_bits(&bits, &buf[2], (AC3_HEADER_SIZE-2) * 8); - strmtyp = get_bits(&bits, 2); - substreamid = get_bits(&bits, 3); - - if (strmtyp != 0 || substreamid != 0) - return 0; /* Currently don't support additional streams */ - - frmsiz = get_bits(&bits, 11) + 1; - fscod = get_bits(&bits, 2); - if (fscod == 3) { - fscod2 = get_bits(&bits, 2); - numblkscod = 3; - - if(fscod2 == 3) - return 0; - - *sample_rate = ff_ac3_freqs[fscod2] / 2; - } else { - numblkscod = get_bits(&bits, 2); - - *sample_rate = ff_ac3_freqs[fscod]; - } - - acmod = get_bits(&bits, 3); - lfeon = get_bits1(&bits); - - *samples = eac3_blocks[numblkscod] * 256; - *bit_rate = frmsiz * (*sample_rate) * 16 / (*samples); - *channels = ff_ac3_channels[acmod] + lfeon; - - return frmsiz * 2; - } - - /* Unsupported bitstream version */ - return 0; -} -#endif /* CONFIG_AC3_PARSER */ - -#ifdef CONFIG_AAC_PARSER -static int aac_sync(const uint8_t *buf, int *channels, int *sample_rate, - int *bit_rate, int *samples) -{ - GetBitContext bits; - int size, rdb, ch, sr; - - init_get_bits(&bits, buf, AAC_HEADER_SIZE * 8); - - if(get_bits(&bits, 12) != 0xfff) - return 0; - - skip_bits1(&bits); /* id */ - skip_bits(&bits, 2); /* layer */ - skip_bits1(&bits); /* protection_absent */ - skip_bits(&bits, 2); /* profile_objecttype */ - sr = get_bits(&bits, 4); /* sample_frequency_index */ - if(!aac_sample_rates[sr]) - return 0; - skip_bits1(&bits); /* private_bit */ - ch = get_bits(&bits, 3); /* channel_configuration */ - if(!aac_channels[ch]) - return 0; - skip_bits1(&bits); /* original/copy */ - skip_bits1(&bits); /* home */ - - /* adts_variable_header */ - skip_bits1(&bits); /* copyright_identification_bit */ - skip_bits1(&bits); /* copyright_identification_start */ - size = get_bits(&bits, 13); /* aac_frame_length */ - skip_bits(&bits, 11); /* adts_buffer_fullness */ - rdb = get_bits(&bits, 2); /* number_of_raw_data_blocks_in_frame */ - - *channels = aac_channels[ch]; - *sample_rate = aac_sample_rates[sr]; - *samples = (rdb + 1) * 1024; - *bit_rate = size * 8 * *sample_rate / *samples; - - return size; -} -#endif /* CONFIG_AAC_PARSER */ - -#ifdef CONFIG_AC3_PARSER -static int ac3_parse_init(AVCodecParserContext *s1) -{ - AC3ParseContext *s = s1->priv_data; - s->inbuf_ptr = s->inbuf; - s->header_size = AC3_HEADER_SIZE; - s->sync = ac3_sync; - return 0; -} -#endif - -#ifdef CONFIG_AAC_PARSER -static int aac_parse_init(AVCodecParserContext *s1) -{ - AC3ParseContext *s = s1->priv_data; - s->inbuf_ptr = s->inbuf; - s->header_size = AAC_HEADER_SIZE; - s->sync = aac_sync; - return 0; -} -#endif - -/* also used for ADTS AAC */ -static int ac3_parse(AVCodecParserContext *s1, - AVCodecContext *avctx, - const uint8_t **poutbuf, int *poutbuf_size, - const uint8_t *buf, int buf_size) -{ - AC3ParseContext *s = s1->priv_data; - const uint8_t *buf_ptr; - int len, sample_rate, bit_rate, channels, samples; - - *poutbuf = NULL; - *poutbuf_size = 0; - - buf_ptr = buf; - while (buf_size > 0) { - len = s->inbuf_ptr - s->inbuf; - if (s->frame_size == 0) { - /* no header seen : find one. We need at least s->header_size - bytes to parse it */ - len = FFMIN(s->header_size - len, buf_size); - - memcpy(s->inbuf_ptr, buf_ptr, len); - buf_ptr += len; - s->inbuf_ptr += len; - buf_size -= len; - if ((s->inbuf_ptr - s->inbuf) == s->header_size) { - len = s->sync(s->inbuf, &channels, &sample_rate, &bit_rate, - &samples); - if (len == 0) { - /* no sync found : move by one byte (inefficient, but simple!) */ - memmove(s->inbuf, s->inbuf + 1, s->header_size - 1); - s->inbuf_ptr--; - } else { - s->frame_size = len; - /* update codec info */ - avctx->sample_rate = sample_rate; - /* set channels,except if the user explicitly requests 1 or 2 channels, XXX/FIXME this is a bit ugly */ - if(avctx->codec_id == CODEC_ID_AC3){ - if(avctx->channels!=1 && avctx->channels!=2){ - avctx->channels = channels; - } - } else { - avctx->channels = channels; - } - avctx->bit_rate = bit_rate; - avctx->frame_size = samples; - } - } - } else { - len = FFMIN(s->frame_size - len, buf_size); - - memcpy(s->inbuf_ptr, buf_ptr, len); - buf_ptr += len; - s->inbuf_ptr += len; - buf_size -= len; - - if(s->inbuf_ptr - s->inbuf == s->frame_size){ - *poutbuf = s->inbuf; - *poutbuf_size = s->frame_size; - s->inbuf_ptr = s->inbuf; - s->frame_size = 0; - break; - } - } - } - return buf_ptr - buf; -} -#endif /* CONFIG_AC3_PARSER || CONFIG_AAC_PARSER */ - -#ifdef CONFIG_AC3_PARSER -AVCodecParser ac3_parser = { - { CODEC_ID_AC3 }, - sizeof(AC3ParseContext), - ac3_parse_init, - ac3_parse, - NULL, -}; -#endif -#ifdef CONFIG_AAC_PARSER -AVCodecParser aac_parser = { - { CODEC_ID_AAC }, - sizeof(AC3ParseContext), - aac_parse_init, - ac3_parse, - NULL, -}; -#endif |