voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size) { VocDecContext *voc = s->priv_data; AVCodecContext *dec = st->codec; ByteIOContext *pb = s->pb; VocType type; int size, tmp_codec; int sample_rate = 0; int channels = 1; while (!voc->remaining_size) { type = get_byte(pb); if (type == VOC_TYPE_EOF) return AVERROR(EIO); voc->remaining_size = get_le24(pb); if (!voc->remaining_size) { if (url_is_streamed(s->pb)) return AVERROR(EIO); voc->remaining_size = url_fsize(pb) - url_ftell(pb); } max_size -= 4; switch (type) { case VOC_TYPE_VOICE_DATA: dec->sample_rate = 1000000 / (256 - get_byte(pb)); if (sample_rate) dec->sample_rate = sample_rate; dec->channels = channels; tmp_codec = ff_codec_get_id(ff_voc_codec_tags, get_byte(pb)); if (dec->codec_id == CODEC_ID_NONE) dec->codec_id = tmp_codec; else if (dec->codec_id != tmp_codec) av_log(s, AV_LOG_WARNING, "Ignoring mid-stream change in audio codec\n"); dec->bits_per_coded_sample = av_get_bits_per_sample(dec->codec_id); voc->remaining_size -= 2; max_size -= 2; channels = 1; break; case VOC_TYPE_VOICE_DATA_CONT: break; case VOC_TYPE_EXTENDED: sample_rate = get_le16(pb); get_byte(pb); channels = get_byte(pb) + 1; sample_rate = 256000000 / (channels * (65536 - sample_rate)); voc->remaining_size = 0; max_size -= 4; break; case VOC_TYPE_NEW_VOICE_DATA: dec->sample_rate = get_le32(pb); dec->bits_per_coded_sample = get_byte(pb); dec->channels = get_byte(pb); tmp_codec = ff_codec_get_id(ff_voc_codec_tags, get_le16(pb)); if (dec->codec_id == CODEC_ID_NONE) dec->codec_id = tmp_codec; else if (dec->codec_id != tmp_codec) av_log(s, AV_LOG_WARNING, "Ignoring mid-stream change in audio codec\n"); url_fskip(pb, 4); voc->remaining_size -= 12; max_size -= 12; break; default: url_fskip(pb, voc->remaining_size); max_size -= voc->remaining_size; voc->remaining_size = 0; break; } if (dec->codec_id == CODEC_ID_NONE) { av_log(s, AV_LOG_ERROR, "Invalid codec_id\n"); if (s->audio_codec_id == CODEC_ID_NONE) return AVERROR(EINVAL); } } dec->bit_rate = dec->sample_rate * dec->bits_per_coded_sample; if (max_size <= 0) max_size = 2048; size = FFMIN(voc->remaining_size, max_size); voc->remaining_size -= size; return av_get_packet(pb, pkt, size); }