/* * CRYO APC audio format demuxer * Copyright (c) 2007 Anssi Hannula <anssi.hannula@gmail.com> * * 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 <string.h> #include "avformat.h" static int apc_probe(AVProbeData *p) { if (!strncmp(p->buf, "CRYO_APC", 8)) return AVPROBE_SCORE_MAX; return 0; } static int apc_read_header(AVFormatContext *s) { AVIOContext *pb = s->pb; AVStream *st; avio_rl32(pb); /* CRYO */ avio_rl32(pb); /* _APC */ avio_rl32(pb); /* 1.20 */ st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); st->codec->codec_type = AVMEDIA_TYPE_AUDIO; st->codec->codec_id = CODEC_ID_ADPCM_IMA_APC; avio_rl32(pb); /* number of samples */ st->codec->sample_rate = avio_rl32(pb); st->codec->extradata_size = 2 * 4; st->codec->extradata = av_malloc(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE); if (!st->codec->extradata) return AVERROR(ENOMEM); /* initial predictor values for adpcm decoder */ avio_read(pb, st->codec->extradata, 2 * 4); st->codec->channels = 1; if (avio_rl32(pb)) st->codec->channels = 2; st->codec->bits_per_coded_sample = 4; st->codec->bit_rate = st->codec->bits_per_coded_sample * st->codec->channels * st->codec->sample_rate; st->codec->block_align = 1; return 0; } #define MAX_READ_SIZE 4096 static int apc_read_packet(AVFormatContext *s, AVPacket *pkt) { if (av_get_packet(s->pb, pkt, MAX_READ_SIZE) <= 0) return AVERROR(EIO); pkt->stream_index = 0; return 0; } AVInputFormat ff_apc_demuxer = { .name = "apc", .long_name = NULL_IF_CONFIG_SMALL("CRYO APC format"), .read_probe = apc_probe, .read_header = apc_read_header, .read_packet = apc_read_packet, };