static int tta_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { const uint8_t *buf = avpkt->data; int buf_size = avpkt->size; TTAContext *s = avctx->priv_data; int i; init_get_bits(&s->gb, buf, buf_size*8); { int32_t predictors[s->channels]; TTAFilter filters[s->channels]; TTARice rices[s->channels]; int cur_chan = 0, framelen = s->frame_length; int32_t *p; // FIXME: seeking s->total_frames--; if (!s->total_frames && s->last_frame_length) framelen = s->last_frame_length; // init per channel states for (i = 0; i < s->channels; i++) { predictors[i] = 0; ttafilter_init(&(filters[i]), ttafilter_configs[s->bps-1][0], ttafilter_configs[s->bps-1][1]); rice_init(&(rices[i]), 10, 10); } for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) { int32_t *predictor = &(predictors[cur_chan]); TTAFilter *filter = &(filters[cur_chan]); TTARice *rice = &(rices[cur_chan]); uint32_t unary, depth, k; int32_t value; unary = tta_get_unary(&s->gb); if (unary == 0) { depth = 0; k = rice->k0; } else { depth = 1; k = rice->k1; unary--; } if (k) value = (unary << k) + get_bits(&s->gb, k); else value = unary; // FIXME: copy paste from original switch (depth) { case 1: rice->sum1 += value - (rice->sum1 >> 4); if (rice->k1 > 0 && rice->sum1 < shift_16[rice->k1]) rice->k1--; else if(rice->sum1 > shift_16[rice->k1 + 1]) rice->k1++; value += shift_1[rice->k0]; default: rice->sum0 += value - (rice->sum0 >> 4); if (rice->k0 > 0 && rice->sum0 < shift_16[rice->k0]) rice->k0--; else if(rice->sum0 > shift_16[rice->k0 + 1]) rice->k0++; } // extract coded value #define UNFOLD(x) (((x)&1) ? (++(x)>>1) : (-(x)>>1)) *p = UNFOLD(value); // run hybrid filter ttafilter_process(filter, p, 0); // fixed order prediction #define PRED(x, k) (int32_t)((((uint64_t)x << k) - x) >> k) switch (s->bps) { case 1: *p += PRED(*predictor, 4); break; case 2: case 3: *p += PRED(*predictor, 5); break; case 4: *p += *predictor; break; } *predictor = *p; #if 0 // extract 32bit float from last two int samples if (s->is_float && ((p - data) & 1)) { uint32_t neg = *p & 0x80000000; uint32_t hi = *(p - 1); uint32_t lo = abs(*p) - 1; hi += (hi || lo) ? 0x3f80 : 0; // SWAP16: swap all the 16 bits *(p - 1) = (hi << 16) | SWAP16(lo) | neg; } #endif /*if ((get_bits_count(&s->gb)+7)/8 > buf_size) { av_log(NULL, AV_LOG_INFO, "overread!!\n"); break; }*/ // flip channels if (cur_chan < (s->channels-1)) cur_chan++; else { // decorrelate in case of stereo integer if (!s->is_float && (s->channels > 1)) { int32_t *r = p - 1; for (*p += *r / 2; r > p - s->channels; r--) *r = *(r + 1) - *r; } cur_chan = 0; } } skip_bits(&s->gb, 32); // frame crc // convert to output buffer switch(s->bps) { case 2: { uint16_t *samples = data; for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) { // *samples++ = (unsigned char)*p; // *samples++ = (unsigned char)(*p >> 8); *samples++ = *p; } *data_size = (uint8_t *)samples - (uint8_t *)data; break; } default: av_log(s->avctx, AV_LOG_ERROR, "Error, only 16bit samples supported!\n"); } } // return get_bits_count(&s->gb)+7)/8; return buf_size; }