Libav 0.7.1
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00001 /* 00002 * id RoQ (.roq) File Demuxer 00003 * Copyright (c) 2003 The ffmpeg Project 00004 * 00005 * This file is part of Libav. 00006 * 00007 * Libav is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * Libav is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with Libav; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00030 #include "libavutil/intreadwrite.h" 00031 #include "avformat.h" 00032 00033 #define RoQ_MAGIC_NUMBER 0x1084 00034 #define RoQ_CHUNK_PREAMBLE_SIZE 8 00035 #define RoQ_AUDIO_SAMPLE_RATE 22050 00036 #define RoQ_CHUNKS_TO_SCAN 30 00037 00038 #define RoQ_INFO 0x1001 00039 #define RoQ_QUAD_CODEBOOK 0x1002 00040 #define RoQ_QUAD_VQ 0x1011 00041 #define RoQ_SOUND_MONO 0x1020 00042 #define RoQ_SOUND_STEREO 0x1021 00043 00044 typedef struct RoqDemuxContext { 00045 00046 int width; 00047 int height; 00048 int audio_channels; 00049 00050 int video_stream_index; 00051 int audio_stream_index; 00052 00053 int64_t video_pts; 00054 unsigned int audio_frame_count; 00055 00056 } RoqDemuxContext; 00057 00058 static int roq_probe(AVProbeData *p) 00059 { 00060 if ((AV_RL16(&p->buf[0]) != RoQ_MAGIC_NUMBER) || 00061 (AV_RL32(&p->buf[2]) != 0xFFFFFFFF)) 00062 return 0; 00063 00064 return AVPROBE_SCORE_MAX; 00065 } 00066 00067 static int roq_read_header(AVFormatContext *s, 00068 AVFormatParameters *ap) 00069 { 00070 RoqDemuxContext *roq = s->priv_data; 00071 AVIOContext *pb = s->pb; 00072 int framerate; 00073 AVStream *st; 00074 unsigned char preamble[RoQ_CHUNK_PREAMBLE_SIZE]; 00075 00076 /* get the main header */ 00077 if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) != 00078 RoQ_CHUNK_PREAMBLE_SIZE) 00079 return AVERROR(EIO); 00080 framerate = AV_RL16(&preamble[6]); 00081 00082 /* init private context parameters */ 00083 roq->width = roq->height = roq->audio_channels = roq->video_pts = 00084 roq->audio_frame_count = 0; 00085 roq->audio_stream_index = -1; 00086 00087 st = av_new_stream(s, 0); 00088 if (!st) 00089 return AVERROR(ENOMEM); 00090 av_set_pts_info(st, 63, 1, framerate); 00091 roq->video_stream_index = st->index; 00092 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 00093 st->codec->codec_id = CODEC_ID_ROQ; 00094 st->codec->codec_tag = 0; /* no fourcc */ 00095 00096 return 0; 00097 } 00098 00099 static int roq_read_packet(AVFormatContext *s, 00100 AVPacket *pkt) 00101 { 00102 RoqDemuxContext *roq = s->priv_data; 00103 AVIOContext *pb = s->pb; 00104 int ret = 0; 00105 unsigned int chunk_size; 00106 unsigned int chunk_type; 00107 unsigned int codebook_size; 00108 unsigned char preamble[RoQ_CHUNK_PREAMBLE_SIZE]; 00109 int packet_read = 0; 00110 int64_t codebook_offset; 00111 00112 while (!packet_read) { 00113 00114 if (s->pb->eof_reached) 00115 return AVERROR(EIO); 00116 00117 /* get the next chunk preamble */ 00118 if ((ret = avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE)) != 00119 RoQ_CHUNK_PREAMBLE_SIZE) 00120 return AVERROR(EIO); 00121 00122 chunk_type = AV_RL16(&preamble[0]); 00123 chunk_size = AV_RL32(&preamble[2]); 00124 if(chunk_size > INT_MAX) 00125 return AVERROR_INVALIDDATA; 00126 00127 switch (chunk_type) { 00128 00129 case RoQ_INFO: 00130 if (!roq->width || !roq->height) { 00131 AVStream *st = s->streams[roq->video_stream_index]; 00132 if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) != RoQ_CHUNK_PREAMBLE_SIZE) 00133 return AVERROR(EIO); 00134 st->codec->width = roq->width = AV_RL16(preamble); 00135 st->codec->height = roq->height = AV_RL16(preamble + 2); 00136 break; 00137 } 00138 /* don't care about this chunk anymore */ 00139 avio_skip(pb, RoQ_CHUNK_PREAMBLE_SIZE); 00140 break; 00141 00142 case RoQ_QUAD_CODEBOOK: 00143 /* packet needs to contain both this codebook and next VQ chunk */ 00144 codebook_offset = avio_tell(pb) - RoQ_CHUNK_PREAMBLE_SIZE; 00145 codebook_size = chunk_size; 00146 avio_skip(pb, codebook_size); 00147 if (avio_read(pb, preamble, RoQ_CHUNK_PREAMBLE_SIZE) != 00148 RoQ_CHUNK_PREAMBLE_SIZE) 00149 return AVERROR(EIO); 00150 chunk_size = AV_RL32(&preamble[2]) + RoQ_CHUNK_PREAMBLE_SIZE * 2 + 00151 codebook_size; 00152 00153 /* rewind */ 00154 avio_seek(pb, codebook_offset, SEEK_SET); 00155 00156 /* load up the packet */ 00157 ret= av_get_packet(pb, pkt, chunk_size); 00158 if (ret != chunk_size) 00159 return AVERROR(EIO); 00160 pkt->stream_index = roq->video_stream_index; 00161 pkt->pts = roq->video_pts++; 00162 00163 packet_read = 1; 00164 break; 00165 00166 case RoQ_SOUND_MONO: 00167 case RoQ_SOUND_STEREO: 00168 if (roq->audio_stream_index == -1) { 00169 AVStream *st = av_new_stream(s, 1); 00170 if (!st) 00171 return AVERROR(ENOMEM); 00172 av_set_pts_info(st, 32, 1, RoQ_AUDIO_SAMPLE_RATE); 00173 roq->audio_stream_index = st->index; 00174 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 00175 st->codec->codec_id = CODEC_ID_ROQ_DPCM; 00176 st->codec->codec_tag = 0; /* no tag */ 00177 st->codec->channels = roq->audio_channels = chunk_type == RoQ_SOUND_STEREO ? 2 : 1; 00178 st->codec->sample_rate = RoQ_AUDIO_SAMPLE_RATE; 00179 st->codec->bits_per_coded_sample = 16; 00180 st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * 00181 st->codec->bits_per_coded_sample; 00182 st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample; 00183 } 00184 case RoQ_QUAD_VQ: 00185 /* load up the packet */ 00186 if (av_new_packet(pkt, chunk_size + RoQ_CHUNK_PREAMBLE_SIZE)) 00187 return AVERROR(EIO); 00188 /* copy over preamble */ 00189 memcpy(pkt->data, preamble, RoQ_CHUNK_PREAMBLE_SIZE); 00190 00191 if (chunk_type == RoQ_QUAD_VQ) { 00192 pkt->stream_index = roq->video_stream_index; 00193 pkt->pts = roq->video_pts++; 00194 } else { 00195 pkt->stream_index = roq->audio_stream_index; 00196 pkt->pts = roq->audio_frame_count; 00197 roq->audio_frame_count += (chunk_size / roq->audio_channels); 00198 } 00199 00200 pkt->pos= avio_tell(pb); 00201 ret = avio_read(pb, pkt->data + RoQ_CHUNK_PREAMBLE_SIZE, 00202 chunk_size); 00203 if (ret != chunk_size) 00204 ret = AVERROR(EIO); 00205 00206 packet_read = 1; 00207 break; 00208 00209 default: 00210 av_log(s, AV_LOG_ERROR, " unknown RoQ chunk (%04X)\n", chunk_type); 00211 return AVERROR_INVALIDDATA; 00212 break; 00213 } 00214 } 00215 00216 return ret; 00217 } 00218 00219 AVInputFormat ff_roq_demuxer = { 00220 "RoQ", 00221 NULL_IF_CONFIG_SMALL("id RoQ format"), 00222 sizeof(RoqDemuxContext), 00223 roq_probe, 00224 roq_read_header, 00225 roq_read_packet, 00226 };