[FFmpeg-cvslog] r15961 - in trunk/libavcodec: qcelpdata.h qcelpdec.c
vitor
subversion
Sun Nov 30 18:18:17 CET 2008
Author: vitor
Date: Sun Nov 30 18:18:17 2008
New Revision: 15961
Log:
More OKed parts of the QCELP decoder
patch by Kenan Gillet, kenan.gillet gmail com
Modified:
trunk/libavcodec/qcelpdata.h
trunk/libavcodec/qcelpdec.c
Modified: trunk/libavcodec/qcelpdata.h
==============================================================================
--- trunk/libavcodec/qcelpdata.h (original)
+++ trunk/libavcodec/qcelpdata.h Sun Nov 30 18:18:17 2008
@@ -34,6 +34,33 @@
#include "libavutil/common.h"
/**
+ * QCELP unpacked data frame
+ */
+typedef struct {
+/// @defgroup qcelp_codebook_parameters QCELP excitation codebook parameters
+/// @{
+ uint8_t cbsign[16]; ///!< sign of the codebook gain for each codebook subframe
+ uint8_t cbgain[16]; ///!< unsigned codebook gain for each codebook subframe
+ uint8_t cindex[16]; ///!< codebook index for each codebook subframe
+/// @}
+
+/// @defgroup qcelp_pitch_parameters QCELP pitch prediction parameters
+/// @{
+ uint8_t plag[4]; ///!< pitch lag for each pitch subframe
+ uint8_t pfrac[4]; ///!< fractional pitch lag for each pitch subframe
+ uint8_t pgain[4]; ///!< pitch gain for each pitch subframe
+/// @}
+
+ /**
+ * line spectral pair frequencies (LSP) for RATE_OCTAVE,
+ * line spectral pair frequencies grouped into five vectors
+ * of dimension two (LSPV) for other rates
+ */
+ uint8_t lspv[10];
+
+} QCELPFrame;
+
+/**
* pre-calculated table for hammsinc function
* Only half of the table is needed because of symmetry.
*
@@ -47,7 +74,7 @@ typedef struct {
uint8_t bitlen; /*!< number of bits to read */
} QCELPBitmap;
-#define QCELP_OF(variable, bit, len) {offsetof(QCELPContext, variable), bit, len}
+#define QCELP_OF(variable, bit, len) {offsetof(QCELPFrame, variable), bit, len}
/* Disable the below code for now to allow 'make checkheaders' to pass. */
#if 0
@@ -243,7 +270,7 @@ static const QCELPBitmap * const qcelp_u
qcelp_rate_full_bitmap,
};
-static const uint16_t qcelp_bits_per_rate[5] = {
+static const uint16_t qcelp_unpacking_bitmaps_lengths[5] = {
0, ///!< for SILENCE rate
FF_ARRAY_ELEMS(qcelp_rate_octave_bitmap),
FF_ARRAY_ELEMS(qcelp_rate_quarter_bitmap),
Modified: trunk/libavcodec/qcelpdec.c
==============================================================================
--- trunk/libavcodec/qcelpdec.c (original)
+++ trunk/libavcodec/qcelpdec.c Sun Nov 30 18:18:17 2008
@@ -40,6 +40,24 @@
#undef NDEBUG
#include <assert.h>
+typedef struct {
+ GetBitContext gb;
+ qcelp_packet_rate bitrate;
+ QCELPFrame frame; /*!< unpacked data frame */
+ uint8_t erasure_count;
+ uint8_t octave_count; /*!< count the consecutive RATE_OCTAVE frames */
+ float prev_lspf[10];
+ float predictor_lspf[10]; /*!< LSP predictor,
+ only use for RATE_OCTAVE and I_F_Q */
+ float formant_mem[170];
+ float last_codebook_gain;
+ int prev_g1[2];
+ int prev_bitrate;
+ float prev_pitch_gain[4];
+ uint8_t prev_pitch_lag[4];
+ uint16_t first16bits;
+} QCELPContext;
+
static void weighted_vector_sumf(float *out, const float *in_a,
const float *in_b, float weight_coeff_a,
float weight_coeff_b, int length)
@@ -99,8 +117,8 @@ static int decode_lspf(QCELPContext *q,
for(i=0; i<10; i++)
{
q->predictor_lspf[i] =
- lspf[i] = (q->lspv[i] ? QCELP_LSP_SPREAD_FACTOR
- : -QCELP_LSP_SPREAD_FACTOR)
+ lspf[i] = (q->frame.lspv[i] ? QCELP_LSP_SPREAD_FACTOR
+ : -QCELP_LSP_SPREAD_FACTOR)
+ predictors[i] * QCELP_LSP_OCTAVE_PREDICTOR
+ (i + 1) * ((1 - QCELP_LSP_OCTAVE_PREDICTOR)/11);
}
@@ -141,8 +159,8 @@ static int decode_lspf(QCELPContext *q,
tmp_lspf = 0.;
for(i=0; i<5 ; i++)
{
- lspf[2*i+0] = tmp_lspf += qcelp_lspvq[i][q->lspv[i]][0] * 0.0001;
- lspf[2*i+1] = tmp_lspf += qcelp_lspvq[i][q->lspv[i]][1] * 0.0001;
+ lspf[2*i+0] = tmp_lspf += qcelp_lspvq[i][q->frame.lspv[i]][0] * 0.0001;
+ lspf[2*i+1] = tmp_lspf += qcelp_lspvq[i][q->frame.lspv[i]][1] * 0.0001;
}
// Check for badly received packets.
@@ -166,6 +184,83 @@ static int decode_lspf(QCELPContext *q,
}
/**
+ * Converts codebook transmission codes to GAIN and INDEX.
+ *
+ * @param q the context
+ * @param gain array holding the decoded gain
+ *
+ * TIA/EIA/IS-733 2.4.6.2
+ */
+static void decode_gain_and_index(QCELPContext *q,
+ float *gain) {
+ int i, subframes_count, g1[16];
+ float slope;
+
+ if (q->bitrate >= RATE_QUARTER) {
+ switch (q->bitrate) {
+ case RATE_FULL: subframes_count = 16; break;
+ case RATE_HALF: subframes_count = 4; break;
+ default: subframes_count = 5;
+ }
+ for (i = 0; i < subframes_count; i++) {
+ g1[i] = 4 * q->frame.cbgain[i];
+ if (q->bitrate == RATE_FULL && !((i+1) & 3)) {
+ g1[i] += av_clip((g1[i-1] + g1[i-2] + g1[i-3]) / 3 - 6, 0, 32);
+ }
+
+ gain[i] = qcelp_g12ga[g1[i]];
+
+ if (q->frame.cbsign[i]) {
+ gain[i] = -gain[i];
+ q->frame.cindex[i] = (q->frame.cindex[i]-89) & 127;
+ }
+ }
+
+ q->prev_g1[0] = g1[i-2];
+ q->prev_g1[1] = g1[i-1];
+ q->last_codebook_gain = qcelp_g12ga[g1[i-1]];
+
+ if (q->bitrate == RATE_QUARTER) {
+ // Provide smoothing of the unvoiced excitation energy.
+ gain[7] = gain[4];
+ gain[6] = 0.4*gain[3] + 0.6*gain[4];
+ gain[5] = gain[3];
+ gain[4] = 0.8*gain[2] + 0.2*gain[3];
+ gain[3] = 0.2*gain[1] + 0.8*gain[2];
+ gain[2] = gain[1];
+ gain[1] = 0.6*gain[0] + 0.4*gain[1];
+ }
+ } else {
+ if (q->bitrate == RATE_OCTAVE) {
+ g1[0] = 2 * q->frame.cbgain[0]
+ + av_clip((q->prev_g1[0] + q->prev_g1[1]) / 2 - 5, 0, 54);
+ subframes_count = 8;
+ } else {
+ assert(q->bitrate == I_F_Q);
+
+ g1[0] = q->prev_g1[1];
+ switch (q->erasure_count) {
+ case 1 : break;
+ case 2 : g1[0] -= 1; break;
+ case 3 : g1[0] -= 2; break;
+ default: g1[0] -= 6;
+ }
+ if (g1[0] < 0)
+ g1[0] = 0;
+ subframes_count = 4;
+ }
+ // This interpolation is done to produce smoother background noise.
+ slope = 0.5*(qcelp_g12ga[g1[0]] - q->last_codebook_gain) / subframes_count;
+ for (i = 1; i <= subframes_count; i++)
+ gain[i-1] = q->last_codebook_gain + slope * i;
+ q->last_codebook_gain = gain[i-2];
+
+ q->prev_g1[0] = q->prev_g1[1];
+ q->prev_g1[1] = g1[0];
+ }
+}
+
+/**
* If the received packet is Rate 1/4 a further sanity check is made of the
* codebook gain.
*
@@ -224,7 +319,7 @@ static void compute_svector(const QCELPC
for(i=0; i<16; i++)
{
tmp_gain = gain[i] * QCELP_RATE_FULL_CODEBOOK_RATIO;
- cindex = -q->cindex[i];
+ cindex = -q->frame.cindex[i];
for(j=0; j<10; j++)
*cdn_vector++ = tmp_gain * qcelp_rate_full_codebook[cindex++ & 127];
}
@@ -233,17 +328,17 @@ static void compute_svector(const QCELPC
for(i=0; i<4; i++)
{
tmp_gain = gain[i] * QCELP_RATE_HALF_CODEBOOK_RATIO;
- cindex = -q->cindex[i];
+ cindex = -q->frame.cindex[i];
for (j = 0; j < 40; j++)
*cdn_vector++ = tmp_gain * qcelp_rate_half_codebook[cindex++ & 127];
}
break;
case RATE_QUARTER:
- cbseed = (0x0003 & q->lspv[4])<<14 |
- (0x003F & q->lspv[3])<< 8 |
- (0x0060 & q->lspv[2])<< 1 |
- (0x0007 & q->lspv[1])<< 3 |
- (0x0038 & q->lspv[0])>> 3 ;
+ cbseed = (0x0003 & q->frame.lspv[4])<<14 |
+ (0x003F & q->frame.lspv[3])<< 8 |
+ (0x0060 & q->frame.lspv[2])<< 1 |
+ (0x0007 & q->frame.lspv[1])<< 3 |
+ (0x0038 & q->frame.lspv[0])>> 3 ;
rnd = q->rnd_fir_filter_mem + 20;
for(i=0; i<8; i++)
{
@@ -439,6 +534,107 @@ static void warn_insufficient_frame_qual
message);
}
+static int qcelp_decode_frame(AVCodecContext *avctx,
+ void *data,
+ int *data_size,
+ uint8_t *buf,
+ const int buf_size) {
+ QCELPContext *q = avctx->priv_data;
+ float *outbuffer = data;
+ int i;
+ float quantized_lspf[10], lpc[10];
+ float gain[16];
+ float *formant_mem;
+
+ if ((q->bitrate = determine_bitrate(avctx, buf_size, &buf)) == I_F_Q) {
+ warn_insufficient_frame_quality(avctx, "bitrate cannot be determined.");
+ goto erasure;
+ }
+
+ if (q->bitrate == RATE_OCTAVE &&
+ (q->first16bits = AV_RB16(buf)) == 0xFFFF) {
+ warn_insufficient_frame_quality(avctx, "Bitrate is 1/8 and first 16 bits are on.");
+ goto erasure;
+ }
+
+ if (q->bitrate > SILENCE) {
+ const QCELPBitmap *bitmaps = qcelp_unpacking_bitmaps_per_rate[q->bitrate];
+ const QCELPBitmap *bitmaps_end = qcelp_unpacking_bitmaps_per_rate[q->bitrate]
+ + qcelp_unpacking_bitmaps_lengths[q->bitrate];
+ uint8_t *unpacked_data = (uint8_t *)&q->frame;
+
+ init_get_bits(&q->gb, buf, 8*buf_size);
+
+ memset(&q->frame, 0, sizeof(QCELPFrame));
+
+ for (; bitmaps < bitmaps_end; bitmaps++)
+ unpacked_data[bitmaps->index] |= get_bits(&q->gb, bitmaps->bitlen) << bitmaps->bitpos;
+
+ // Check for erasures/blanks on rates 1, 1/4 and 1/8.
+ if (q->frame.reserved) {
+ warn_insufficient_frame_quality(avctx, "Wrong data in reserved frame area.");
+ goto erasure;
+ }
+ if (q->bitrate == RATE_QUARTER && codebook_sanity_check_for_rate_quarter(q->frame.cbgain)) {
+ warn_insufficient_frame_quality(avctx, "Codebook gain sanity check failed.");
+ goto erasure;
+ }
+
+ if (q->bitrate >= RATE_HALF) {
+ for (i = 0; i < 4; i++) {
+ if (q->frame.pfrac[i] && q->frame.plag[i] >= 124) {
+ warn_insufficient_frame_quality(avctx, "Cannot initialize pitch filter.");
+ goto erasure;
+ }
+ }
+ }
+ }
+
+ decode_gain_and_index(q, gain);
+ compute_svector(q, gain, outbuffer);
+
+ if (decode_lspf(q, quantized_lspf) < 0) {
+ warn_insufficient_frame_quality(avctx, "Badly received packets in frame.");
+ goto erasure;
+ }
+
+
+ apply_pitch_filters(q, outbuffer);
+
+ if (q->bitrate == I_F_Q) {
+erasure:
+ q->bitrate = I_F_Q;
+ q->erasure_count++;
+ decode_gain_and_index(q, gain);
+ compute_svector(q, gain, outbuffer);
+ decode_lspf(q, quantized_lspf);
+ apply_pitch_filters(q, outbuffer);
+ } else
+ q->erasure_count = 0;
+
+ formant_mem = q->formant_mem + 10;
+ for (i = 0; i < 4; i++) {
+ interpolate_lpc(q, quantized_lspf, lpc, i);
+ ff_celp_lp_synthesis_filterf(formant_mem, lpc, outbuffer + i * 40, 40, 10);
+ formant_mem += 40;
+ }
+ memcpy(q->formant_mem, q->formant_mem + 160, 10 * sizeof(float));
+
+ // FIXME: postfilter and final gain control should be here.
+ // TIA/EIA/IS-733 2.4.8.6
+
+ formant_mem = q->formant_mem + 10;
+ for (i = 0; i < 160; i++)
+ *outbuffer++ = av_clipf(*formant_mem++, QCELP_CLIP_LOWER_BOUND, QCELP_CLIP_UPPER_BOUND);
+
+ memcpy(q->prev_lspf, quantized_lspf, sizeof(q->prev_lspf));
+ q->prev_bitrate = q->bitrate;
+
+ *data_size = 160 * sizeof(*outbuffer);
+
+ return *data_size;
+}
+
AVCodec qcelp_decoder =
{
.name = "qcelp",
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