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author | Vladimir Voroshilov <voroshil@gmail.com> | 2009-06-18 18:14:38 +0000 |
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committer | Vladimir Voroshilov <voroshil@gmail.com> | 2009-06-18 18:14:38 +0000 |
commit | 17dbe25438555b9fea85b057d1f39c054b6d4164 (patch) | |
tree | 1d55e821be94efeb297a98aed66fc4e83301933d /libavcodec/g729dec.c | |
parent | 71ee65155916730b124064e51f090c7fc0f59b71 (diff) | |
download | ffmpeg-streaming-17dbe25438555b9fea85b057d1f39c054b6d4164.zip ffmpeg-streaming-17dbe25438555b9fea85b057d1f39c054b6d4164.tar.gz |
G.729 decoding routine (skeleton, including parameters decoding).
Originally committed as revision 19218 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/g729dec.c')
-rw-r--r-- | libavcodec/g729dec.c | 113 |
1 files changed, 92 insertions, 21 deletions
diff --git a/libavcodec/g729dec.c b/libavcodec/g729dec.c index 28c48b5..08a3a09 100644 --- a/libavcodec/g729dec.c +++ b/libavcodec/g729dec.c @@ -72,15 +72,32 @@ #define SHARP_MAX 13017 typedef struct { - int sample_rate; - uint8_t packed_frame_size; ///< input frame size(in bytes) - uint8_t unpacked_frame_size;///< output frame size (in bytes) + uint8_t ac_index_bits[2]; ///< adaptive codebook index for second subframe (size in bits) + uint8_t parity_bit; ///< parity bit for pitch delay + uint8_t gc_1st_index_bits; ///< gain codebook (first stage) index (size in bits) + uint8_t gc_2nd_index_bits; ///< gain codebook (second stage) index (size in bits) + uint8_t fc_signs_bits; ///< number of pulses in fixed-codebook vector uint8_t fc_indexes_bits; ///< size (in bits) of fixed-codebook index entry - - /// mr_energy = mean_energy + 10 * log10(2^26 * subframe_size) in (7.13) - int mr_energy; } G729FormatDescription; +static const G729FormatDescription format_g729_8k = { + .ac_index_bits = {8,5}, + .parity_bit = 1, + .gc_1st_index_bits = GC_1ST_IDX_BITS_8K, + .gc_2nd_index_bits = GC_2ND_IDX_BITS_8K, + .fc_signs_bits = 4, + .fc_indexes_bits = 13, +}; + +static const G729FormatDescription format_g729d_6k4 = { + .ac_index_bits = {8,4}, + .parity_bit = 0, + .gc_1st_index_bits = GC_1ST_IDX_BITS_6K4, + .gc_2nd_index_bits = GC_2ND_IDX_BITS_6K4, + .fc_signs_bits = 2, + .fc_indexes_bits = 9, +}; + /** * \brief pseudo random number generator */ @@ -110,6 +127,64 @@ static av_cold int decoder_init(AVCodecContext * avctx) return 0; } +static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, + AVPacket *avpkt) +{ + const uint8_t *buf = avpkt->data; + int buf_size = avpkt->size; + int16_t *out_frame = data; + GetBitContext gb; + G729FormatDescription format; + int frame_erasure = 0; ///< frame erasure detected during decoding + int bad_pitch = 0; ///< parity check failed + int i; + uint8_t ma_predictor; ///< switched MA predictor of LSP quantizer + uint8_t quantizer_1st; ///< first stage vector of quantizer + uint8_t quantizer_2nd_lo; ///< second stage lower vector of quantizer (size in bits) + uint8_t quantizer_2nd_hi; ///< second stage higher vector of quantizer (size in bits) + + if (*data_size < SUBFRAME_SIZE << 2) { + av_log(avctx, AV_LOG_ERROR, "Error processing packet: output buffer too small\n"); + return AVERROR(EIO); + } + + if (buf_size == 10) { + format = format_g729_8k; + av_log(avctx, AV_LOG_DEBUG, "Packet type: %s\n", "G.729 @ 8kbit/s"); + } else if (buf_size == 8) { + format = format_g729d_6k4; + av_log(avctx, AV_LOG_DEBUG, "Packet type: %s\n", "G.729D @ 6.4kbit/s"); + } else { + av_log(avctx, AV_LOG_ERROR, "Packet size %d is unknown.\n", buf_size); + return (AVERROR_NOFMT); + } + + for (i=0; i < buf_size; i++) + frame_erasure |= buf[i]; + frame_erasure = !frame_erasure; + + init_get_bits(&gb, buf, buf_size); + + ma_predictor = get_bits(&gb, 1); + quantizer_1st = get_bits(&gb, VQ_1ST_BITS); + quantizer_2nd_lo = get_bits(&gb, VQ_2ND_BITS); + quantizer_2nd_hi = get_bits(&gb, VQ_2ND_BITS); + + for (i = 0; i < 2; i++) { + uint8_t ac_index; ///< adaptive codebook index + uint8_t pulses_signs; ///< fixed-codebook vector pulse signs + int fc_indexes; ///< fixed-codebook indexes + uint8_t gc_1st_index; ///< gain codebook (first stage) index + uint8_t gc_2nd_index; ///< gain codebook (second stage) index + + ac_index = get_bits(&gb, format.ac_index_bits[i]); + if(!i && format.parity_bit) + bad_pitch = get_parity(ac_index) == get_bits1(&gb); + fc_indexes = get_bits(&gb, format.fc_indexes_bits); + pulses_signs = get_bits(&gb, format.fc_signs_bits); + gc_1st_index = get_bits(&gb, format.gc_1st_index_bits); + gc_2nd_index = get_bits(&gb, format.gc_2nd_index_bits); + ff_acelp_weighted_vector_sum(fc + pitch_delay_int[i], fc + pitch_delay_int[i], fc, 1 << 14, @@ -117,32 +192,28 @@ static av_cold int decoder_init(AVCodecContext * avctx) 0, 14, SUBFRAME_SIZE - pitch_delay_int[i]); - if (ctx->frame_erasure) { + if (frame_erasure) { ctx->gain_pitch = (29491 * ctx->gain_pitch) >> 15; // 0.90 (0.15) ctx->gain_code = ( 2007 * ctx->gain_code ) >> 11; // 0.98 (0.11) gain_corr_factor = 0; } else { - ctx->gain_pitch = cb_gain_1st_8k[parm->gc_1st_index[i]][0] + - cb_gain_2nd_8k[parm->gc_2nd_index[i]][0]; - gain_corr_factor = cb_gain_1st_8k[parm->gc_1st_index[i]][1] + - cb_gain_2nd_8k[parm->gc_2nd_index[i]][1]; + ctx->gain_pitch = cb_gain_1st_8k[gc_1st_index][0] + + cb_gain_2nd_8k[gc_2nd_index][0]; + gain_corr_factor = cb_gain_1st_8k[gc_1st_index][1] + + cb_gain_2nd_8k[gc_2nd_index][1]; ff_acelp_weighted_vector_sum(ctx->exc + i * SUBFRAME_SIZE, ctx->exc + i * SUBFRAME_SIZE, fc, - (!voicing && ctx->frame_erasure) ? 0 : ctx->gain_pitch, - ( voicing && ctx->frame_erasure) ? 0 : ctx->gain_code, + (!voicing && frame_erasure) ? 0 : ctx->gain_pitch, + ( voicing && frame_erasure) ? 0 : ctx->gain_code, 1 << 13, 14, SUBFRAME_SIZE); - - if (buf_size < packed_frame_size) { - av_log(avctx, AV_LOG_ERROR, "Error processing packet: packet size too small\n"); - return AVERROR(EIO); - } - if (*data_size < unpacked_frame_size) { - av_log(avctx, AV_LOG_ERROR, "Error processing packet: output buffer too small\n"); - return AVERROR(EIO); } + *data_size = SUBFRAME_SIZE << 2; + return buf_size; +} + AVCodec g729_decoder = { "g729", |