FFmpeg: libavformat/4xm.c Source File

00001 /*
00002  * 4X Technologies .4xm File Demuxer (no muxer)
00003  * Copyright (c) 2003  The ffmpeg Project
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 {
00096     AVIOContext *pb = s->pb;
00097     unsigned int fourcc_tag;
00098     unsigned int size;
00099     int header_size;
00100     FourxmDemuxContext *fourxm = s->priv_data;
00101     unsigned char *header;
00102     int i, ret;
00103     AVStream *st;
00104 
00105     fourxm->track_count = 0;
00106     fourxm->tracks = NULL;
00107     fourxm->fps = 1.0;
00108 
00109     /* skip the first 3 32-bit numbers */
00110     avio_skip(pb, 12);
00111 
00112     /* check for LIST-HEAD */
00113     GET_LIST_HEADER();
00114     header_size = size - 4;
00115     if (fourcc_tag != HEAD_TAG || header_size < 0)
00116         return AVERROR_INVALIDDATA;
00117 
00118     /* allocate space for the header and load the whole thing */
00119     header = av_malloc(header_size);
00120     if (!header)
00121         return AVERROR(ENOMEM);
00122     if (avio_read(pb, header, header_size) != header_size){
00123         av_free(header);
00124         return AVERROR(EIO);
00125     }
00126 
00127     /* take the lazy approach and search for any and all vtrk and strk chunks */
00128     for (i = 0; i < header_size - 8; i++) {
00129         fourcc_tag = AV_RL32(&header[i]);
00130         size = AV_RL32(&header[i + 4]);
00131         if (size > header_size - i - 8 && (fourcc_tag == vtrk_TAG || fourcc_tag == strk_TAG)) {
00132             av_log(s, AV_LOG_ERROR, "chunk larger than array %d>%d\n", size, header_size - i - 8);
00133             return AVERROR_INVALIDDATA;
00134         }
00135 
00136         if (fourcc_tag == std__TAG) {
00137             fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));
00138         } else if (fourcc_tag == vtrk_TAG) {
00139             /* check that there is enough data */
00140             if (size != vtrk_SIZE) {
00141                 ret= AVERROR_INVALIDDATA;
00142                 goto fail;
00143             }
00144             fourxm->width  = AV_RL32(&header[i + 36]);
00145             fourxm->height = AV_RL32(&header[i + 40]);
00146 
00147             /* allocate a new AVStream */
00148             st = avformat_new_stream(s, NULL);
00149             if (!st){
00150                 ret= AVERROR(ENOMEM);
00151                 goto fail;
00152             }
00153             avpriv_set_pts_info(st, 60, 1, fourxm->fps);
00154 
00155             fourxm->video_stream_index = st->index;
00156 
00157             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00158             st->codec->codec_id = AV_CODEC_ID_4XM;
00159             st->codec->extradata_size = 4;
00160             st->codec->extradata = av_malloc(4);
00161             AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16]));
00162             st->codec->width  = fourxm->width;
00163             st->codec->height = fourxm->height;
00164 
00165             i += 8 + size;
00166         } else if (fourcc_tag == strk_TAG) {
00167             int current_track;
00168             /* check that there is enough data */
00169             if (size != strk_SIZE) {
00170                 ret= AVERROR_INVALIDDATA;
00171                 goto fail;
00172             }
00173             current_track = AV_RL32(&header[i + 8]);
00174             if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){
00175                 av_log(s, AV_LOG_ERROR, "current_track too large\n");
00176                 ret = AVERROR_INVALIDDATA;
00177                 goto fail;
00178             }
00179             if (current_track + 1 > fourxm->track_count) {
00180                 fourxm->tracks = av_realloc_f(fourxm->tracks,
00181                                               sizeof(AudioTrack),
00182                                               current_track + 1);
00183                 if (!fourxm->tracks) {
00184                     ret = AVERROR(ENOMEM);
00185                     goto fail;
00186                 }
00187                 memset(&fourxm->tracks[fourxm->track_count], 0,
00188                        sizeof(AudioTrack) * (current_track + 1 - fourxm->track_count));
00189                 fourxm->track_count = current_track + 1;
00190             }
00191             fourxm->tracks[current_track].adpcm       = AV_RL32(&header[i + 12]);
00192             fourxm->tracks[current_track].channels    = AV_RL32(&header[i + 36]);
00193             fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]);
00194             fourxm->tracks[current_track].bits        = AV_RL32(&header[i + 44]);
00195             fourxm->tracks[current_track].audio_pts   = 0;
00196             if(   fourxm->tracks[current_track].channels    <= 0
00197                || fourxm->tracks[current_track].sample_rate <= 0
00198                || fourxm->tracks[current_track].bits        <  0){
00199                 av_log(s, AV_LOG_ERROR, "audio header invalid\n");
00200                 ret = AVERROR_INVALIDDATA;
00201                 goto fail;
00202             }
00203             if(!fourxm->tracks[current_track].adpcm && fourxm->tracks[current_track].bits<8){
00204                 av_log(s, AV_LOG_ERROR, "bits unspecified for non ADPCM\n");
00205                 ret = AVERROR_INVALIDDATA;
00206                 goto fail;
00207             }
00208             i += 8 + size;
00209 
00210             /* allocate a new AVStream */
00211             st = avformat_new_stream(s, NULL);
00212             if (!st){
00213                 ret= AVERROR(ENOMEM);
00214                 goto fail;
00215             }
00216 
00217             st->id = current_track;
00218             avpriv_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
00219 
00220             fourxm->tracks[current_track].stream_index = st->index;
00221 
00222             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00223             st->codec->codec_tag = 0;
00224             st->codec->channels              = fourxm->tracks[current_track].channels;
00225             st->codec->sample_rate           = fourxm->tracks[current_track].sample_rate;
00226             st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
00227             st->codec->bit_rate              = st->codec->channels * st->codec->sample_rate *
00228                 st->codec->bits_per_coded_sample;
00229             st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00230             if (fourxm->tracks[current_track].adpcm){
00231                 st->codec->codec_id = AV_CODEC_ID_ADPCM_4XM;
00232             }else if (st->codec->bits_per_coded_sample == 8){
00233                 st->codec->codec_id = AV_CODEC_ID_PCM_U8;
00234             }else
00235                 st->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
00236         }
00237     }
00238 
00239     /* skip over the LIST-MOVI chunk (which is where the stream should be */
00240     GET_LIST_HEADER();
00241     if (fourcc_tag != MOVI_TAG){
00242         ret= AVERROR_INVALIDDATA;
00243         goto fail;
00244     }
00245 
00246     av_free(header);
00247     /* initialize context members */
00248     fourxm->video_pts = -1;  /* first frame will push to 0 */
00249 
00250     return 0;
00251 fail:
00252     av_freep(&fourxm->tracks);
00253     av_free(header);
00254     return ret;
00255 }
00256 
00257 static int fourxm_read_packet(AVFormatContext *s,
00258                               AVPacket *pkt)
00259 {
00260     FourxmDemuxContext *fourxm = s->priv_data;
00261     AVIOContext *pb = s->pb;
00262     unsigned int fourcc_tag;
00263     unsigned int size;
00264     int ret = 0;
00265     unsigned int track_number;
00266     int packet_read = 0;
00267     unsigned char header[8];
00268     int audio_frame_count;
00269 
00270     while (!packet_read) {
00271 
00272         if ((ret = avio_read(s->pb, header, 8)) < 0)
00273             return ret;
00274         fourcc_tag = AV_RL32(&header[0]);
00275         size = AV_RL32(&header[4]);
00276         if (url_feof(pb))
00277             return AVERROR(EIO);
00278         switch (fourcc_tag) {
00279 
00280         case LIST_TAG:
00281             /* this is a good time to bump the video pts */
00282             fourxm->video_pts ++;
00283 
00284             /* skip the LIST-* tag and move on to the next fourcc */
00285             avio_rl32(pb);
00286             break;
00287 
00288         case ifrm_TAG:
00289         case pfrm_TAG:
00290         case cfrm_TAG:
00291         case ifr2_TAG:
00292         case pfr2_TAG:
00293         case cfr2_TAG:
00294             /* allocate 8 more bytes than 'size' to account for fourcc
00295              * and size */
00296             if (size + 8 < size || av_new_packet(pkt, size + 8))
00297                 return AVERROR(EIO);
00298             pkt->stream_index = fourxm->video_stream_index;
00299             pkt->pts = fourxm->video_pts;
00300             pkt->pos = avio_tell(s->pb);
00301             memcpy(pkt->data, header, 8);
00302             ret = avio_read(s->pb, &pkt->data[8], size);
00303 
00304             if (ret < 0){
00305                 av_free_packet(pkt);
00306             }else
00307                 packet_read = 1;
00308             break;
00309 
00310         case snd__TAG:
00311             track_number = avio_rl32(pb);
00312             avio_skip(pb, 4);
00313             size-=8;
00314 
00315             if (track_number < fourxm->track_count && fourxm->tracks[track_number].channels>0) {
00316                 ret= av_get_packet(s->pb, pkt, size);
00317                 if(ret<0)
00318                     return AVERROR(EIO);
00319                 pkt->stream_index =
00320                     fourxm->tracks[track_number].stream_index;
00321                 pkt->pts = fourxm->tracks[track_number].audio_pts;
00322                 packet_read = 1;
00323 
00324                 /* pts accounting */
00325                 audio_frame_count = size;
00326                 if (fourxm->tracks[track_number].adpcm)
00327                     audio_frame_count -=
00328                         2 * (fourxm->tracks[track_number].channels);
00329                 audio_frame_count /=
00330                       fourxm->tracks[track_number].channels;
00331                 if (fourxm->tracks[track_number].adpcm){
00332                     audio_frame_count *= 2;
00333                 }else
00334                     audio_frame_count /=
00335                     (fourxm->tracks[track_number].bits / 8);
00336                 fourxm->tracks[track_number].audio_pts += audio_frame_count;
00337 
00338             } else {
00339                 avio_skip(pb, size);
00340             }
00341             break;
00342 
00343         default:
00344             avio_skip(pb, size);
00345             break;
00346         }
00347     }
00348     return ret;
00349 }
00350 
00351 static int fourxm_read_close(AVFormatContext *s)
00352 {
00353     FourxmDemuxContext *fourxm = s->priv_data;
00354 
00355     av_freep(&fourxm->tracks);
00356 
00357     return 0;
00358 }
00359 
00360 AVInputFormat ff_fourxm_demuxer = {
00361     .name           = "4xm",
00362     .long_name      = NULL_IF_CONFIG_SMALL("4X Technologies"),
00363     .priv_data_size = sizeof(FourxmDemuxContext),
00364     .read_probe     = fourxm_probe,
00365     .read_header    = fourxm_read_header,
00366     .read_packet    = fourxm_read_packet,
00367     .read_close     = fourxm_read_close,
00368 };