static int g722_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { G722Context *c = avctx->priv_data; int16_t *out_buf = data; int j, out_len = 0; const int skip = 8 - avctx->bits_per_coded_sample; const int16_t *quantizer_table = low_inv_quants[skip]; GetBitContext gb; init_get_bits(&gb, avpkt->data, avpkt->size * 8); for (j = 0; j < avpkt->size; j++) { int ilow, ihigh, rlow, rhigh, dhigh; int xout1, xout2; ihigh = get_bits(&gb, 2); ilow = get_bits(&gb, 6 - skip); skip_bits(&gb, skip); rlow = av_clip((c->band[0].scale_factor * quantizer_table[ilow] >> 10) + c->band[0].s_predictor, -16384, 16383); ff_g722_update_low_predictor(&c->band[0], ilow >> (2 - skip)); dhigh = c->band[1].scale_factor * ff_g722_high_inv_quant[ihigh] >> 10; rhigh = av_clip(dhigh + c->band[1].s_predictor, -16384, 16383); ff_g722_update_high_predictor(&c->band[1], dhigh, ihigh); c->prev_samples[c->prev_samples_pos++] = rlow + rhigh; c->prev_samples[c->prev_samples_pos++] = rlow - rhigh; ff_g722_apply_qmf(c->prev_samples + c->prev_samples_pos - 24, &xout1, &xout2); out_buf[out_len++] = av_clip_int16(xout1 >> 12); out_buf[out_len++] = av_clip_int16(xout2 >> 12); if (c->prev_samples_pos >= PREV_SAMPLES_BUF_SIZE) { memmove(c->prev_samples, c->prev_samples + c->prev_samples_pos - 22, 22 * sizeof(c->prev_samples[0])); c->prev_samples_pos = 22; } } *data_size = out_len << 1; return avpkt->size; }