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libavformat/4xm.c

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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 "libavutil/intfloat.h"
00032 #include "avformat.h"
00033 #include "internal.h"
00034 
00035 #define     RIFF_TAG MKTAG('R', 'I', 'F', 'F')
00036 #define  FOURXMV_TAG MKTAG('4', 'X', 'M', 'V')
00037 #define     LIST_TAG MKTAG('L', 'I', 'S', 'T')
00038 #define     HEAD_TAG MKTAG('H', 'E', 'A', 'D')
00039 #define     TRK__TAG MKTAG('T', 'R', 'K', '_')
00040 #define     MOVI_TAG MKTAG('M', 'O', 'V', 'I')
00041 #define     VTRK_TAG MKTAG('V', 'T', 'R', 'K')
00042 #define     STRK_TAG MKTAG('S', 'T', 'R', 'K')
00043 #define     std__TAG MKTAG('s', 't', 'd', '_')
00044 #define     name_TAG MKTAG('n', 'a', 'm', 'e')
00045 #define     vtrk_TAG MKTAG('v', 't', 'r', 'k')
00046 #define     strk_TAG MKTAG('s', 't', 'r', 'k')
00047 #define     ifrm_TAG MKTAG('i', 'f', 'r', 'm')
00048 #define     pfrm_TAG MKTAG('p', 'f', 'r', 'm')
00049 #define     cfrm_TAG MKTAG('c', 'f', 'r', 'm')
00050 #define     ifr2_TAG MKTAG('i', 'f', 'r', '2')
00051 #define     pfr2_TAG MKTAG('p', 'f', 'r', '2')
00052 #define     cfr2_TAG MKTAG('c', 'f', 'r', '2')
00053 #define     snd__TAG MKTAG('s', 'n', 'd', '_')
00054 
00055 #define vtrk_SIZE 0x44
00056 #define strk_SIZE 0x28
00057 
00058 #define GET_LIST_HEADER() \
00059     fourcc_tag = avio_rl32(pb); \
00060     size = avio_rl32(pb); \
00061     if (fourcc_tag != LIST_TAG) \
00062         return AVERROR_INVALIDDATA; \
00063     fourcc_tag = avio_rl32(pb);
00064 
00065 typedef struct AudioTrack {
00066     int sample_rate;
00067     int bits;
00068     int channels;
00069     int stream_index;
00070     int adpcm;
00071     int64_t audio_pts;
00072 } AudioTrack;
00073 
00074 typedef struct FourxmDemuxContext {
00075     int width;
00076     int height;
00077     int video_stream_index;
00078     int track_count;
00079     AudioTrack *tracks;
00080 
00081     int64_t video_pts;
00082     float fps;
00083 } FourxmDemuxContext;
00084 
00085 static int fourxm_probe(AVProbeData *p)
00086 {
00087     if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
00088         (AV_RL32(&p->buf[8]) != FOURXMV_TAG))
00089         return 0;
00090 
00091     return AVPROBE_SCORE_MAX;
00092 }
00093 
00094 static int fourxm_read_header(AVFormatContext *s,
00095                               AVFormatParameters *ap)
00096 {
00097     AVIOContext *pb = s->pb;
00098     unsigned int fourcc_tag;
00099     unsigned int size;
00100     int header_size;
00101     FourxmDemuxContext *fourxm = s->priv_data;
00102     unsigned char *header;
00103     int i, ret;
00104     AVStream *st;
00105 
00106     fourxm->track_count = 0;
00107     fourxm->tracks = NULL;
00108     fourxm->fps = 1.0;
00109 
00110     /* skip the first 3 32-bit numbers */
00111     avio_skip(pb, 12);
00112 
00113     /* check for LIST-HEAD */
00114     GET_LIST_HEADER();
00115     header_size = size - 4;
00116     if (fourcc_tag != HEAD_TAG || header_size < 0)
00117         return AVERROR_INVALIDDATA;
00118 
00119     /* allocate space for the header and load the whole thing */
00120     header = av_malloc(header_size);
00121     if (!header)
00122         return AVERROR(ENOMEM);
00123     if (avio_read(pb, header, header_size) != header_size){
00124         av_free(header);
00125         return AVERROR(EIO);
00126     }
00127 
00128     /* take the lazy approach and search for any and all vtrk and strk chunks */
00129     for (i = 0; i < header_size - 8; i++) {
00130         fourcc_tag = AV_RL32(&header[i]);
00131         size = AV_RL32(&header[i + 4]);
00132 
00133         if (fourcc_tag == std__TAG) {
00134             fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));
00135         } else if (fourcc_tag == vtrk_TAG) {
00136             /* check that there is enough data */
00137             if (size != vtrk_SIZE) {
00138                 ret= AVERROR_INVALIDDATA;
00139                 goto fail;
00140             }
00141             fourxm->width  = AV_RL32(&header[i + 36]);
00142             fourxm->height = AV_RL32(&header[i + 40]);
00143 
00144             /* allocate a new AVStream */
00145             st = avformat_new_stream(s, NULL);
00146             if (!st){
00147                 ret= AVERROR(ENOMEM);
00148                 goto fail;
00149             }
00150             avpriv_set_pts_info(st, 60, 1, fourxm->fps);
00151 
00152             fourxm->video_stream_index = st->index;
00153 
00154             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00155             st->codec->codec_id = CODEC_ID_4XM;
00156             st->codec->extradata_size = 4;
00157             st->codec->extradata = av_malloc(4);
00158             AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16]));
00159             st->codec->width  = fourxm->width;
00160             st->codec->height = fourxm->height;
00161 
00162             i += 8 + size;
00163         } else if (fourcc_tag == strk_TAG) {
00164             int current_track;
00165             /* check that there is enough data */
00166             if (size != strk_SIZE) {
00167                 ret= AVERROR_INVALIDDATA;
00168                 goto fail;
00169             }
00170             current_track = AV_RL32(&header[i + 8]);
00171             if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){
00172                 av_log(s, AV_LOG_ERROR, "current_track too large\n");
00173                 ret= -1;
00174                 goto fail;
00175             }
00176             if (current_track + 1 > fourxm->track_count) {
00177                 fourxm->tracks = av_realloc(fourxm->tracks,
00178                     (current_track + 1) * sizeof(AudioTrack));
00179                 if (!fourxm->tracks) {
00180                     ret = AVERROR(ENOMEM);
00181                     goto fail;
00182                 }
00183                 memset(&fourxm->tracks[fourxm->track_count], 0,
00184                        sizeof(AudioTrack) * (current_track + 1 - fourxm->track_count));
00185                 fourxm->track_count = current_track + 1;
00186             }
00187             fourxm->tracks[current_track].adpcm       = AV_RL32(&header[i + 12]);
00188             fourxm->tracks[current_track].channels    = AV_RL32(&header[i + 36]);
00189             fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]);
00190             fourxm->tracks[current_track].bits        = AV_RL32(&header[i + 44]);
00191             fourxm->tracks[current_track].audio_pts   = 0;
00192             if(   fourxm->tracks[current_track].channels    <= 0
00193                || fourxm->tracks[current_track].sample_rate <= 0
00194                || fourxm->tracks[current_track].bits        <  0){
00195                 av_log(s, AV_LOG_ERROR, "audio header invalid\n");
00196                 ret= -1;
00197                 goto fail;
00198             }
00199             i += 8 + size;
00200 
00201             /* allocate a new AVStream */
00202             st = avformat_new_stream(s, NULL);
00203             if (!st){
00204                 ret= AVERROR(ENOMEM);
00205                 goto fail;
00206             }
00207 
00208             st->id = current_track;
00209             avpriv_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
00210 
00211             fourxm->tracks[current_track].stream_index = st->index;
00212 
00213             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00214             st->codec->codec_tag = 0;
00215             st->codec->channels              = fourxm->tracks[current_track].channels;
00216             st->codec->sample_rate           = fourxm->tracks[current_track].sample_rate;
00217             st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
00218             st->codec->bit_rate              = st->codec->channels * st->codec->sample_rate *
00219                 st->codec->bits_per_coded_sample;
00220             st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00221             if (fourxm->tracks[current_track].adpcm){
00222                 st->codec->codec_id = CODEC_ID_ADPCM_4XM;
00223             }else if (st->codec->bits_per_coded_sample == 8){
00224                 st->codec->codec_id = CODEC_ID_PCM_U8;
00225             }else
00226                 st->codec->codec_id = CODEC_ID_PCM_S16LE;
00227         }
00228     }
00229 
00230     /* skip over the LIST-MOVI chunk (which is where the stream should be */
00231     GET_LIST_HEADER();
00232     if (fourcc_tag != MOVI_TAG){
00233         ret= AVERROR_INVALIDDATA;
00234         goto fail;
00235     }
00236 
00237     av_free(header);
00238     /* initialize context members */
00239     fourxm->video_pts = -1;  /* first frame will push to 0 */
00240 
00241     return 0;
00242 fail:
00243     av_freep(&fourxm->tracks);
00244     av_free(header);
00245     return ret;
00246 }
00247 
00248 static int fourxm_read_packet(AVFormatContext *s,
00249                               AVPacket *pkt)
00250 {
00251     FourxmDemuxContext *fourxm = s->priv_data;
00252     AVIOContext *pb = s->pb;
00253     unsigned int fourcc_tag;
00254     unsigned int size;
00255     int ret = 0;
00256     unsigned int track_number;
00257     int packet_read = 0;
00258     unsigned char header[8];
00259     int audio_frame_count;
00260 
00261     while (!packet_read) {
00262 
00263         if ((ret = avio_read(s->pb, header, 8)) < 0)
00264             return ret;
00265         fourcc_tag = AV_RL32(&header[0]);
00266         size = AV_RL32(&header[4]);
00267         if (pb->eof_reached)
00268             return AVERROR(EIO);
00269         switch (fourcc_tag) {
00270 
00271         case LIST_TAG:
00272             /* this is a good time to bump the video pts */
00273             fourxm->video_pts ++;
00274 
00275             /* skip the LIST-* tag and move on to the next fourcc */
00276             avio_rl32(pb);
00277             break;
00278 
00279         case ifrm_TAG:
00280         case pfrm_TAG:
00281         case cfrm_TAG:
00282         case ifr2_TAG:
00283         case pfr2_TAG:
00284         case cfr2_TAG:
00285             /* allocate 8 more bytes than 'size' to account for fourcc
00286              * and size */
00287             if (size + 8 < size || av_new_packet(pkt, size + 8))
00288                 return AVERROR(EIO);
00289             pkt->stream_index = fourxm->video_stream_index;
00290             pkt->pts = fourxm->video_pts;
00291             pkt->pos = avio_tell(s->pb);
00292             memcpy(pkt->data, header, 8);
00293             ret = avio_read(s->pb, &pkt->data[8], size);
00294 
00295             if (ret < 0){
00296                 av_free_packet(pkt);
00297             }else
00298                 packet_read = 1;
00299             break;
00300 
00301         case snd__TAG:
00302             track_number = avio_rl32(pb);
00303             avio_skip(pb, 4);
00304             size-=8;
00305 
00306             if (track_number < fourxm->track_count && fourxm->tracks[track_number].channels>0) {
00307                 ret= av_get_packet(s->pb, pkt, size);
00308                 if(ret<0)
00309                     return AVERROR(EIO);
00310                 pkt->stream_index =
00311                     fourxm->tracks[track_number].stream_index;
00312                 pkt->pts = fourxm->tracks[track_number].audio_pts;
00313                 packet_read = 1;
00314 
00315                 /* pts accounting */
00316                 audio_frame_count = size;
00317                 if (fourxm->tracks[track_number].adpcm)
00318                     audio_frame_count -=
00319                         2 * (fourxm->tracks[track_number].channels);
00320                 audio_frame_count /=
00321                       fourxm->tracks[track_number].channels;
00322                 if (fourxm->tracks[track_number].adpcm){
00323                     audio_frame_count *= 2;
00324                 }else
00325                     audio_frame_count /=
00326                     (fourxm->tracks[track_number].bits / 8);
00327                 fourxm->tracks[track_number].audio_pts += audio_frame_count;
00328 
00329             } else {
00330                 avio_skip(pb, size);
00331             }
00332             break;
00333 
00334         default:
00335             avio_skip(pb, size);
00336             break;
00337         }
00338     }
00339     return ret;
00340 }
00341 
00342 static int fourxm_read_close(AVFormatContext *s)
00343 {
00344     FourxmDemuxContext *fourxm = s->priv_data;
00345 
00346     av_freep(&fourxm->tracks);
00347 
00348     return 0;
00349 }
00350 
00351 AVInputFormat ff_fourxm_demuxer = {
00352     .name           = "4xm",
00353     .long_name      = NULL_IF_CONFIG_SMALL("4X Technologies format"),
00354     .priv_data_size = sizeof(FourxmDemuxContext),
00355     .read_probe     = fourxm_probe,
00356     .read_header    = fourxm_read_header,
00357     .read_packet    = fourxm_read_packet,
00358     .read_close     = fourxm_read_close,
00359 };
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