diff options
author | Michael Chinen <mchinen@gmail.com> | 2010-12-07 16:30:18 +0300 |
---|---|---|
committer | Justin Ruggles <justin.ruggles@gmail.com> | 2010-12-07 16:30:18 +0300 |
commit | 625daac4bddda7858d16869c90ba7df95e7702c6 (patch) | |
tree | 5c888a88d3dc8f601bcdaf71d9b6c54d0b4ceca0 /libavcodec/flacdec.c | |
parent | 86b6e387cc16f873d2739af14f63696b648e0423 (diff) |
Move decode_frame_header() from flacdec.c to flac.c/h to share with the
forthcoming FLAC parser.
Patch by Michael Chinen [mchinen at gmail]
Originally committed as revision 25909 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/flacdec.c')
-rw-r--r-- | libavcodec/flacdec.c | 102 |
1 files changed, 1 insertions, 101 deletions
diff --git a/libavcodec/flacdec.c b/libavcodec/flacdec.c index 8488a9d090..f6206947a8 100644 --- a/libavcodec/flacdec.c +++ b/libavcodec/flacdec.c @@ -67,16 +67,6 @@ typedef struct FLACContext { unsigned int allocated_bitstream_size; } FLACContext; -static const int sample_size_table[] = -{ 0, 8, 12, 0, 16, 20, 24, 0 }; - -static int64_t get_utf8(GetBitContext *gb) -{ - int64_t val; - GET_UTF8(val, get_bits(gb, 8), return -1;) - return val; -} - static void allocate_buffers(FLACContext *s); int ff_flac_is_extradata_valid(AVCodecContext *avctx, @@ -480,103 +470,13 @@ static inline int decode_subframe(FLACContext *s, int channel) return 0; } -/** - * Validate and decode a frame header. - * @param avctx AVCodecContext to use as av_log() context - * @param gb GetBitContext from which to read frame header - * @param[out] fi frame information - * @return non-zero on error, 0 if ok - */ -static int decode_frame_header(AVCodecContext *avctx, GetBitContext *gb, - FLACFrameInfo *fi) -{ - int bs_code, sr_code, bps_code; - - /* frame sync code */ - skip_bits(gb, 16); - - /* block size and sample rate codes */ - bs_code = get_bits(gb, 4); - sr_code = get_bits(gb, 4); - - /* channels and decorrelation */ - fi->ch_mode = get_bits(gb, 4); - if (fi->ch_mode < FLAC_MAX_CHANNELS) { - fi->channels = fi->ch_mode + 1; - fi->ch_mode = FLAC_CHMODE_INDEPENDENT; - } else if (fi->ch_mode <= FLAC_CHMODE_MID_SIDE) { - fi->channels = 2; - } else { - av_log(avctx, AV_LOG_ERROR, "invalid channel mode: %d\n", fi->ch_mode); - return -1; - } - - /* bits per sample */ - bps_code = get_bits(gb, 3); - if (bps_code == 3 || bps_code == 7) { - av_log(avctx, AV_LOG_ERROR, "invalid sample size code (%d)\n", - bps_code); - return -1; - } - fi->bps = sample_size_table[bps_code]; - - /* reserved bit */ - if (get_bits1(gb)) { - av_log(avctx, AV_LOG_ERROR, "broken stream, invalid padding\n"); - return -1; - } - - /* sample or frame count */ - if (get_utf8(gb) < 0) { - av_log(avctx, AV_LOG_ERROR, "utf8 fscked\n"); - return -1; - } - - /* blocksize */ - if (bs_code == 0) { - av_log(avctx, AV_LOG_ERROR, "reserved blocksize code: 0\n"); - return -1; - } else if (bs_code == 6) { - fi->blocksize = get_bits(gb, 8) + 1; - } else if (bs_code == 7) { - fi->blocksize = get_bits(gb, 16) + 1; - } else { - fi->blocksize = ff_flac_blocksize_table[bs_code]; - } - - /* sample rate */ - if (sr_code < 12) { - fi->samplerate = ff_flac_sample_rate_table[sr_code]; - } else if (sr_code == 12) { - fi->samplerate = get_bits(gb, 8) * 1000; - } else if (sr_code == 13) { - fi->samplerate = get_bits(gb, 16); - } else if (sr_code == 14) { - fi->samplerate = get_bits(gb, 16) * 10; - } else { - av_log(avctx, AV_LOG_ERROR, "illegal sample rate code %d\n", - sr_code); - return -1; - } - - /* header CRC-8 check */ - skip_bits(gb, 8); - if (av_crc(av_crc_get_table(AV_CRC_8_ATM), 0, gb->buffer, - get_bits_count(gb)/8)) { - av_log(avctx, AV_LOG_ERROR, "header crc mismatch\n"); - return -1; - } - - return 0; -} - static int decode_frame(FLACContext *s) { int i; GetBitContext *gb = &s->gb; FLACFrameInfo fi; - if (decode_frame_header(s->avctx, gb, &fi)) { + if (ff_flac_decode_frame_header(s->avctx, gb, &fi)) { av_log(s->avctx, AV_LOG_ERROR, "invalid frame header\n"); return -1; } |