static int wv_read_block_header(AVFormatContext *ctx, AVIOContext *pb) { WVContext *wc = ctx->priv_data; int ret; int rate, bpp, chan; uint32_t chmask, flags; wc->pos = avio_tell(pb); /* don't return bogus packets with the ape tag data */ if (wc->apetag_start && wc->pos >= wc->apetag_start) return AVERROR_EOF; ret = avio_read(pb, wc->block_header, WV_HEADER_SIZE); if (ret != WV_HEADER_SIZE) return (ret < 0) ? ret : AVERROR_EOF; ret = ff_wv_parse_header(&wc->header, wc->block_header); if (ret < 0) { av_log(ctx, AV_LOG_ERROR, "Invalid block header.\n"); return ret; } if (wc->header.version < 0x402 || wc->header.version > 0x410) { av_log(ctx, AV_LOG_ERROR, "Unsupported version %03X\n", wc->header.version); return AVERROR_PATCHWELCOME; } /* Blocks with zero samples don't contain actual audio information * and should be ignored */ if (!wc->header.samples) return 0; // parse flags flags = wc->header.flags; bpp = ((flags & 3) + 1) << 3; chan = 1 + !(flags & WV_MONO); chmask = flags & WV_MONO ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO; rate = wv_rates[(flags >> 23) & 0xF]; wc->multichannel = !(wc->header.initial && wc->header.final); if (wc->multichannel) { chan = wc->chan; chmask = wc->chmask; } if ((rate == -1 || !chan) && !wc->block_parsed) { int64_t block_end = avio_tell(pb) + wc->header.blocksize; if (!pb->seekable) { av_log(ctx, AV_LOG_ERROR, "Cannot determine additional parameters\n"); return AVERROR_INVALIDDATA; } while (avio_tell(pb) < block_end) { int id, size; id = avio_r8(pb); size = (id & 0x80) ? avio_rl24(pb) : avio_r8(pb); size <<= 1; if (id & 0x40) size--; switch (id & 0x3F) { case 0xD: if (size <= 1) { av_log(ctx, AV_LOG_ERROR, "Insufficient channel information\n"); return AVERROR_INVALIDDATA; } chan = avio_r8(pb); switch (size - 2) { case 0: chmask = avio_r8(pb); break; case 1: chmask = avio_rl16(pb); break; case 2: chmask = avio_rl24(pb); break; case 3: chmask = avio_rl32(pb); break; case 5: avio_skip(pb, 1); chan |= (avio_r8(pb) & 0xF) << 8; chmask = avio_rl24(pb); break; default: av_log(ctx, AV_LOG_ERROR, "Invalid channel info size %d\n", size); return AVERROR_INVALIDDATA; } break; case 0x27: rate = avio_rl24(pb); break; default: avio_skip(pb, size); } if (id & 0x40) avio_skip(pb, 1); } if (rate == -1) { av_log(ctx, AV_LOG_ERROR, "Cannot determine custom sampling rate\n"); return AVERROR_INVALIDDATA; } avio_seek(pb, block_end - wc->header.blocksize, SEEK_SET); } if (!wc->bpp) wc->bpp = bpp; if (!wc->chan) wc->chan = chan; if (!wc->chmask) wc->chmask = chmask; if (!wc->rate) wc->rate = rate; if (flags && bpp != wc->bpp) { av_log(ctx, AV_LOG_ERROR, "Bits per sample differ, this block: %i, header block: %i\n", bpp, wc->bpp); return AVERROR_INVALIDDATA; } if (flags && !wc->multichannel && chan != wc->chan) { av_log(ctx, AV_LOG_ERROR, "Channels differ, this block: %i, header block: %i\n", chan, wc->chan); return AVERROR_INVALIDDATA; } if (flags && rate != -1 && rate != wc->rate) { av_log(ctx, AV_LOG_ERROR, "Sampling rate differ, this block: %i, header block: %i\n", rate, wc->rate); return AVERROR_INVALIDDATA; } return 0; }