Libav 0.7.1
|
00001 /* 00002 * 4X Technologies .4xm File Demuxer (no muxer) 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 RIFF_TAG MKTAG('R', 'I', 'F', 'F') 00034 #define FOURXMV_TAG MKTAG('4', 'X', 'M', 'V') 00035 #define LIST_TAG MKTAG('L', 'I', 'S', 'T') 00036 #define HEAD_TAG MKTAG('H', 'E', 'A', 'D') 00037 #define TRK__TAG MKTAG('T', 'R', 'K', '_') 00038 #define MOVI_TAG MKTAG('M', 'O', 'V', 'I') 00039 #define VTRK_TAG MKTAG('V', 'T', 'R', 'K') 00040 #define STRK_TAG MKTAG('S', 'T', 'R', 'K') 00041 #define std__TAG MKTAG('s', 't', 'd', '_') 00042 #define name_TAG MKTAG('n', 'a', 'm', 'e') 00043 #define vtrk_TAG MKTAG('v', 't', 'r', 'k') 00044 #define strk_TAG MKTAG('s', 't', 'r', 'k') 00045 #define ifrm_TAG MKTAG('i', 'f', 'r', 'm') 00046 #define pfrm_TAG MKTAG('p', 'f', 'r', 'm') 00047 #define cfrm_TAG MKTAG('c', 'f', 'r', 'm') 00048 #define ifr2_TAG MKTAG('i', 'f', 'r', '2') 00049 #define pfr2_TAG MKTAG('p', 'f', 'r', '2') 00050 #define cfr2_TAG MKTAG('c', 'f', 'r', '2') 00051 #define snd__TAG MKTAG('s', 'n', 'd', '_') 00052 00053 #define vtrk_SIZE 0x44 00054 #define strk_SIZE 0x28 00055 00056 #define GET_LIST_HEADER() \ 00057 fourcc_tag = avio_rl32(pb); \ 00058 size = avio_rl32(pb); \ 00059 if (fourcc_tag != LIST_TAG) \ 00060 return AVERROR_INVALIDDATA; \ 00061 fourcc_tag = avio_rl32(pb); 00062 00063 typedef struct AudioTrack { 00064 int sample_rate; 00065 int bits; 00066 int channels; 00067 int stream_index; 00068 int adpcm; 00069 int64_t audio_pts; 00070 } AudioTrack; 00071 00072 typedef struct FourxmDemuxContext { 00073 int width; 00074 int height; 00075 int video_stream_index; 00076 int track_count; 00077 AudioTrack *tracks; 00078 00079 int64_t video_pts; 00080 float fps; 00081 } FourxmDemuxContext; 00082 00083 static int fourxm_probe(AVProbeData *p) 00084 { 00085 if ((AV_RL32(&p->buf[0]) != RIFF_TAG) || 00086 (AV_RL32(&p->buf[8]) != FOURXMV_TAG)) 00087 return 0; 00088 00089 return AVPROBE_SCORE_MAX; 00090 } 00091 00092 static int fourxm_read_header(AVFormatContext *s, 00093 AVFormatParameters *ap) 00094 { 00095 AVIOContext *pb = s->pb; 00096 unsigned int fourcc_tag; 00097 unsigned int size; 00098 int header_size; 00099 FourxmDemuxContext *fourxm = s->priv_data; 00100 unsigned char *header; 00101 int i, ret; 00102 AVStream *st; 00103 00104 fourxm->track_count = 0; 00105 fourxm->tracks = NULL; 00106 fourxm->fps = 1.0; 00107 00108 /* skip the first 3 32-bit numbers */ 00109 avio_skip(pb, 12); 00110 00111 /* check for LIST-HEAD */ 00112 GET_LIST_HEADER(); 00113 header_size = size - 4; 00114 if (fourcc_tag != HEAD_TAG || header_size < 0) 00115 return AVERROR_INVALIDDATA; 00116 00117 /* allocate space for the header and load the whole thing */ 00118 header = av_malloc(header_size); 00119 if (!header) 00120 return AVERROR(ENOMEM); 00121 if (avio_read(pb, header, header_size) != header_size){ 00122 av_free(header); 00123 return AVERROR(EIO); 00124 } 00125 00126 /* take the lazy approach and search for any and all vtrk and strk chunks */ 00127 for (i = 0; i < header_size - 8; i++) { 00128 fourcc_tag = AV_RL32(&header[i]); 00129 size = AV_RL32(&header[i + 4]); 00130 00131 if (fourcc_tag == std__TAG) { 00132 fourxm->fps = av_int2flt(AV_RL32(&header[i + 12])); 00133 } else if (fourcc_tag == vtrk_TAG) { 00134 /* check that there is enough data */ 00135 if (size != vtrk_SIZE) { 00136 ret= AVERROR_INVALIDDATA; 00137 goto fail; 00138 } 00139 fourxm->width = AV_RL32(&header[i + 36]); 00140 fourxm->height = AV_RL32(&header[i + 40]); 00141 00142 /* allocate a new AVStream */ 00143 st = av_new_stream(s, 0); 00144 if (!st){ 00145 ret= AVERROR(ENOMEM); 00146 goto fail; 00147 } 00148 av_set_pts_info(st, 60, 1, fourxm->fps); 00149 00150 fourxm->video_stream_index = st->index; 00151 00152 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 00153 st->codec->codec_id = CODEC_ID_4XM; 00154 st->codec->extradata_size = 4; 00155 st->codec->extradata = av_malloc(4); 00156 AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16])); 00157 st->codec->width = fourxm->width; 00158 st->codec->height = fourxm->height; 00159 00160 i += 8 + size; 00161 } else if (fourcc_tag == strk_TAG) { 00162 int current_track; 00163 /* check that there is enough data */ 00164 if (size != strk_SIZE) { 00165 ret= AVERROR_INVALIDDATA; 00166 goto fail; 00167 } 00168 current_track = AV_RL32(&header[i + 8]); 00169 if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){ 00170 av_log(s, AV_LOG_ERROR, "current_track too large\n"); 00171 ret= -1; 00172 goto fail; 00173 } 00174 if (current_track + 1 > fourxm->track_count) { 00175 fourxm->track_count = current_track + 1; 00176 fourxm->tracks = av_realloc(fourxm->tracks, 00177 fourxm->track_count * sizeof(AudioTrack)); 00178 if (!fourxm->tracks) { 00179 ret= AVERROR(ENOMEM); 00180 goto fail; 00181 } 00182 } 00183 fourxm->tracks[current_track].adpcm = AV_RL32(&header[i + 12]); 00184 fourxm->tracks[current_track].channels = AV_RL32(&header[i + 36]); 00185 fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]); 00186 fourxm->tracks[current_track].bits = AV_RL32(&header[i + 44]); 00187 fourxm->tracks[current_track].audio_pts = 0; 00188 if( fourxm->tracks[current_track].channels <= 0 00189 || fourxm->tracks[current_track].sample_rate <= 0 00190 || fourxm->tracks[current_track].bits < 0){ 00191 av_log(s, AV_LOG_ERROR, "audio header invalid\n"); 00192 ret= -1; 00193 goto fail; 00194 } 00195 i += 8 + size; 00196 00197 /* allocate a new AVStream */ 00198 st = av_new_stream(s, current_track); 00199 if (!st){ 00200 ret= AVERROR(ENOMEM); 00201 goto fail; 00202 } 00203 00204 av_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate); 00205 00206 fourxm->tracks[current_track].stream_index = st->index; 00207 00208 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 00209 st->codec->codec_tag = 0; 00210 st->codec->channels = fourxm->tracks[current_track].channels; 00211 st->codec->sample_rate = fourxm->tracks[current_track].sample_rate; 00212 st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits; 00213 st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * 00214 st->codec->bits_per_coded_sample; 00215 st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample; 00216 if (fourxm->tracks[current_track].adpcm){ 00217 st->codec->codec_id = CODEC_ID_ADPCM_4XM; 00218 }else if (st->codec->bits_per_coded_sample == 8){ 00219 st->codec->codec_id = CODEC_ID_PCM_U8; 00220 }else 00221 st->codec->codec_id = CODEC_ID_PCM_S16LE; 00222 } 00223 } 00224 00225 /* skip over the LIST-MOVI chunk (which is where the stream should be */ 00226 GET_LIST_HEADER(); 00227 if (fourcc_tag != MOVI_TAG){ 00228 ret= AVERROR_INVALIDDATA; 00229 goto fail; 00230 } 00231 00232 av_free(header); 00233 /* initialize context members */ 00234 fourxm->video_pts = -1; /* first frame will push to 0 */ 00235 00236 return 0; 00237 fail: 00238 av_freep(&fourxm->tracks); 00239 av_free(header); 00240 return ret; 00241 } 00242 00243 static int fourxm_read_packet(AVFormatContext *s, 00244 AVPacket *pkt) 00245 { 00246 FourxmDemuxContext *fourxm = s->priv_data; 00247 AVIOContext *pb = s->pb; 00248 unsigned int fourcc_tag; 00249 unsigned int size; 00250 int ret = 0; 00251 unsigned int track_number; 00252 int packet_read = 0; 00253 unsigned char header[8]; 00254 int audio_frame_count; 00255 00256 while (!packet_read) { 00257 00258 if ((ret = avio_read(s->pb, header, 8)) < 0) 00259 return ret; 00260 fourcc_tag = AV_RL32(&header[0]); 00261 size = AV_RL32(&header[4]); 00262 if (pb->eof_reached) 00263 return AVERROR(EIO); 00264 switch (fourcc_tag) { 00265 00266 case LIST_TAG: 00267 /* this is a good time to bump the video pts */ 00268 fourxm->video_pts ++; 00269 00270 /* skip the LIST-* tag and move on to the next fourcc */ 00271 avio_rl32(pb); 00272 break; 00273 00274 case ifrm_TAG: 00275 case pfrm_TAG: 00276 case cfrm_TAG: 00277 case ifr2_TAG: 00278 case pfr2_TAG: 00279 case cfr2_TAG: 00280 /* allocate 8 more bytes than 'size' to account for fourcc 00281 * and size */ 00282 if (size + 8 < size || av_new_packet(pkt, size + 8)) 00283 return AVERROR(EIO); 00284 pkt->stream_index = fourxm->video_stream_index; 00285 pkt->pts = fourxm->video_pts; 00286 pkt->pos = avio_tell(s->pb); 00287 memcpy(pkt->data, header, 8); 00288 ret = avio_read(s->pb, &pkt->data[8], size); 00289 00290 if (ret < 0){ 00291 av_free_packet(pkt); 00292 }else 00293 packet_read = 1; 00294 break; 00295 00296 case snd__TAG: 00297 track_number = avio_rl32(pb); 00298 avio_skip(pb, 4); 00299 size-=8; 00300 00301 if (track_number < fourxm->track_count && fourxm->tracks[track_number].channels>0) { 00302 ret= av_get_packet(s->pb, pkt, size); 00303 if(ret<0) 00304 return AVERROR(EIO); 00305 pkt->stream_index = 00306 fourxm->tracks[track_number].stream_index; 00307 pkt->pts = fourxm->tracks[track_number].audio_pts; 00308 packet_read = 1; 00309 00310 /* pts accounting */ 00311 audio_frame_count = size; 00312 if (fourxm->tracks[track_number].adpcm) 00313 audio_frame_count -= 00314 2 * (fourxm->tracks[track_number].channels); 00315 audio_frame_count /= 00316 fourxm->tracks[track_number].channels; 00317 if (fourxm->tracks[track_number].adpcm){ 00318 audio_frame_count *= 2; 00319 }else 00320 audio_frame_count /= 00321 (fourxm->tracks[track_number].bits / 8); 00322 fourxm->tracks[track_number].audio_pts += audio_frame_count; 00323 00324 } else { 00325 avio_skip(pb, size); 00326 } 00327 break; 00328 00329 default: 00330 avio_skip(pb, size); 00331 break; 00332 } 00333 } 00334 return ret; 00335 } 00336 00337 static int fourxm_read_close(AVFormatContext *s) 00338 { 00339 FourxmDemuxContext *fourxm = s->priv_data; 00340 00341 av_freep(&fourxm->tracks); 00342 00343 return 0; 00344 } 00345 00346 AVInputFormat ff_fourxm_demuxer = { 00347 "4xm", 00348 NULL_IF_CONFIG_SMALL("4X Technologies format"), 00349 sizeof(FourxmDemuxContext), 00350 fourxm_probe, 00351 fourxm_read_header, 00352 fourxm_read_packet, 00353 fourxm_read_close, 00354 };