static int pcm_decode_frame(AVCodecContext *avctx, void *data, int *data_size, uint8_t *buf, int buf_size) { PCMDecode *s = avctx->priv_data; int c, n; short *samples; uint8_t *src, *src2[MAX_CHANNELS]; samples = data; src = buf; n= av_get_bits_per_sample(avctx->codec_id)/8; if((n && buf_size % n) || avctx->channels > MAX_CHANNELS){ av_log(avctx, AV_LOG_ERROR, "invalid PCM packet\n"); return -1; } buf_size= FFMIN(buf_size, *data_size/2); *data_size=0; n = buf_size/avctx->channels; for(c=0;c<avctx->channels;c++) src2[c] = &src[c*n]; switch(avctx->codec->id) { case CODEC_ID_PCM_S32LE: decode_to16(4, 1, 0, &src, &samples, buf_size); break; case CODEC_ID_PCM_S32BE: decode_to16(4, 0, 0, &src, &samples, buf_size); break; case CODEC_ID_PCM_U32LE: decode_to16(4, 1, 1, &src, &samples, buf_size); break; case CODEC_ID_PCM_U32BE: decode_to16(4, 0, 1, &src, &samples, buf_size); break; case CODEC_ID_PCM_S24LE: decode_to16(3, 1, 0, &src, &samples, buf_size); break; case CODEC_ID_PCM_S24BE: decode_to16(3, 0, 0, &src, &samples, buf_size); break; case CODEC_ID_PCM_U24LE: decode_to16(3, 1, 1, &src, &samples, buf_size); break; case CODEC_ID_PCM_U24BE: decode_to16(3, 0, 1, &src, &samples, buf_size); break; case CODEC_ID_PCM_S24DAUD: n = buf_size / 3; for(;n>0;n--) { uint32_t v = bytestream_get_be24(&src); v >>= 4; // sync flags are here *samples++ = ff_reverse[(v >> 8) & 0xff] + (ff_reverse[v & 0xff] << 8); } break; case CODEC_ID_PCM_S16LE: n = buf_size >> 1; for(;n>0;n--) { *samples++ = bytestream_get_le16(&src); } break; case CODEC_ID_PCM_S16LE_PLANAR: for(n>>=1;n>0;n--) for(c=0;c<avctx->channels;c++) *samples++ = bytestream_get_le16(&src2[c]); src = src2[avctx->channels-1]; break; case CODEC_ID_PCM_S16BE: n = buf_size >> 1; for(;n>0;n--) { *samples++ = bytestream_get_be16(&src); } break; case CODEC_ID_PCM_U16LE: n = buf_size >> 1; for(;n>0;n--) { *samples++ = bytestream_get_le16(&src) - 0x8000; } break; case CODEC_ID_PCM_U16BE: n = buf_size >> 1; for(;n>0;n--) { *samples++ = bytestream_get_be16(&src) - 0x8000; } break; case CODEC_ID_PCM_S8: n = buf_size; for(;n>0;n--) { *samples++ = *src++ << 8; } break; case CODEC_ID_PCM_U8: n = buf_size; for(;n>0;n--) { *samples++ = ((int)*src++ - 128) << 8; } break; case CODEC_ID_PCM_ZORK: n = buf_size; for(;n>0;n--) { int x= *src++; if(x&128) x-= 128; else x = -x; *samples++ = x << 8; } break; case CODEC_ID_PCM_ALAW: case CODEC_ID_PCM_MULAW: n = buf_size; for(;n>0;n--) { *samples++ = s->table[*src++]; } break; default: return -1; } *data_size = (uint8_t *)samples - (uint8_t *)data; return src - buf; }