1/* 2 * Electronic Arts .cdata file Demuxer 3 * Copyright (c) 2007 Peter Ross 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * Electronic Arts cdata Format Demuxer 25 * by Peter Ross (pross@xvid.org) 26 * 27 * Technical details here: 28 * http://wiki.multimedia.cx/index.php?title=EA_Command_And_Conquer_3_Audio_Codec 29 */ 30 31#include "avformat.h" 32 33typedef struct { 34 unsigned int channels; 35 unsigned int audio_pts; 36} CdataDemuxContext; 37 38static int cdata_probe(AVProbeData *p) 39{ 40 const uint8_t *b = p->buf; 41 42 if (b[0] == 0x04 && (b[1] == 0x00 || b[1] == 0x04 || b[1] == 0x0C)) 43 return AVPROBE_SCORE_MAX/8; 44 return 0; 45} 46 47static int cdata_read_header(AVFormatContext *s, AVFormatParameters *ap) 48{ 49 CdataDemuxContext *cdata = s->priv_data; 50 ByteIOContext *pb = s->pb; 51 unsigned int sample_rate, header; 52 AVStream *st; 53 54 header = get_be16(pb); 55 switch (header) { 56 case 0x0400: cdata->channels = 1; break; 57 case 0x0404: cdata->channels = 2; break; 58 case 0x040C: cdata->channels = 4; break; 59 default: 60 av_log(s, AV_LOG_INFO, "unknown header 0x%04x\n", header); 61 return -1; 62 }; 63 64 sample_rate = get_be16(pb); 65 url_fskip(pb, 12); 66 67 st = av_new_stream(s, 0); 68 if (!st) 69 return AVERROR(ENOMEM); 70 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 71 st->codec->codec_tag = 0; /* no fourcc */ 72 st->codec->codec_id = CODEC_ID_ADPCM_EA_XAS; 73 st->codec->channels = cdata->channels; 74 st->codec->sample_rate = sample_rate; 75 av_set_pts_info(st, 64, 1, sample_rate); 76 77 cdata->audio_pts = 0; 78 return 0; 79} 80 81static int cdata_read_packet(AVFormatContext *s, AVPacket *pkt) 82{ 83 CdataDemuxContext *cdata = s->priv_data; 84 int packet_size = 76*cdata->channels; 85 86 int ret = av_get_packet(s->pb, pkt, packet_size); 87 if (ret < 0) 88 return ret; 89 pkt->pts = cdata->audio_pts++; 90 return 0; 91} 92 93AVInputFormat ea_cdata_demuxer = { 94 "ea_cdata", 95 NULL_IF_CONFIG_SMALL("Electronic Arts cdata"), 96 sizeof(CdataDemuxContext), 97 cdata_probe, 98 cdata_read_header, 99 cdata_read_packet, 100 .extensions = "cdata", 101}; 102