[FFmpeg-cvslog] r19218 - trunk/libavcodec/g729dec.c
voroshil
subversion
Thu Jun 18 20:14:39 CEST 2009
Author: voroshil
Date: Thu Jun 18 20:14:38 2009
New Revision: 19218
Log:
G.729 decoding routine (skeleton, including parameters decoding).
Modified:
trunk/libavcodec/g729dec.c
Modified: trunk/libavcodec/g729dec.c
==============================================================================
--- trunk/libavcodec/g729dec.c Thu Jun 18 02:22:08 2009 (r19217)
+++ trunk/libavcodec/g729dec.c Thu Jun 18 20:14:38 2009 (r19218)
@@ -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(AVCodecC
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(AVCodecC
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",
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