/* * Creative Voice File demuxer. * Copyright (c) 2006 Aurelien Jacobs <aurel@gnuage.org> * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/intreadwrite.h" #include "voc.h" #include "internal.h" static int voc_probe(AVProbeData *p) { int version, check; if (memcmp(p->buf, ff_voc_magic, sizeof(ff_voc_magic) - 1)) return 0; version = AV_RL16(p->buf + 22); check = AV_RL16(p->buf + 24); if (~version + 0x1234 != check) return 10; return AVPROBE_SCORE_MAX; } static int voc_read_header(AVFormatContext *s, AVFormatParameters *ap) { VocDecContext *voc = s->priv_data; AVIOContext *pb = s->pb; int header_size; AVStream *st; avio_skip(pb, 20); header_size = avio_rl16(pb) - 22; if (header_size != 4) { av_log(s, AV_LOG_ERROR, "unknown header size: %d\n", header_size); return AVERROR(ENOSYS); } avio_skip(pb, header_size); st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); st->codec->codec_type = AVMEDIA_TYPE_AUDIO; voc->remaining_size = 0; return 0; } int voc_get_packet(AVFormatContext *s, AVPacket *pkt, AVStream *st, int max_size) { VocDecContext *voc = s->priv_data; AVCodecContext *dec = st->codec; AVIOContext *pb = s->pb; VocType type; int size, tmp_codec=-1; int sample_rate = 0; int channels = 1; while (!voc->remaining_size) { type = avio_r8(pb); if (type == VOC_TYPE_EOF) return AVERROR(EIO); voc->remaining_size = avio_rl24(pb); if (!voc->remaining_size) { if (!s->pb->seekable) return AVERROR(EIO); voc->remaining_size = avio_size(pb) - avio_tell(pb); } max_size -= 4; switch (type) { case VOC_TYPE_VOICE_DATA: dec->sample_rate = 1000000 / (256 - avio_r8(pb)); if (sample_rate) dec->sample_rate = sample_rate; dec->channels = channels; tmp_codec = avio_r8(pb); 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 = avio_rl16(pb); avio_r8(pb); channels = avio_r8(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 = avio_rl32(pb); dec->bits_per_coded_sample = avio_r8(pb); dec->channels = avio_r8(pb); tmp_codec = avio_rl16(pb); avio_skip(pb, 4); voc->remaining_size -= 12; max_size -= 12; break; default: avio_skip(pb, voc->remaining_size); max_size -= voc->remaining_size; voc->remaining_size = 0; break; } } if (tmp_codec >= 0) { tmp_codec = ff_codec_get_id(ff_voc_codec_tags, tmp_codec); 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"); if (dec->codec_id == CODEC_ID_NONE) { if (s->audio_codec_id == CODEC_ID_NONE) { av_log(s, AV_LOG_ERROR, "unknown codec tag\n"); return AVERROR(EINVAL); } av_log(s, AV_LOG_WARNING, "unknown codec tag\n"); } } 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); } static int voc_read_packet(AVFormatContext *s, AVPacket *pkt) { return voc_get_packet(s, pkt, s->streams[0], 0); } AVInputFormat ff_voc_demuxer = { .name = "voc", .long_name = NULL_IF_CONFIG_SMALL("Creative Voice file format"), .priv_data_size = sizeof(VocDecContext), .read_probe = voc_probe, .read_header = voc_read_header, .read_packet = voc_read_packet, .codec_tag=(const AVCodecTag* const []){ff_voc_codec_tags, 0}, };