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             if (header_size < i + 16) {
00138                 av_log(s, AV_LOG_ERROR, "std TAG truncated\n");
00139                 return AVERROR_INVALIDDATA;
00140             }
00141             fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));
00142         } else if (fourcc_tag == vtrk_TAG) {
00143             /* check that there is enough data */
00144             if (size != vtrk_SIZE) {
00145                 ret= AVERROR_INVALIDDATA;
00146                 goto fail;
00147             }
00148             fourxm->width  = AV_RL32(&header[i + 36]);
00149             fourxm->height = AV_RL32(&header[i + 40]);
00150 
00151             /* allocate a new AVStream */
00152             st = avformat_new_stream(s, NULL);
00153             if (!st){
00154                 ret= AVERROR(ENOMEM);
00155                 goto fail;
00156             }
00157             avpriv_set_pts_info(st, 60, 1, fourxm->fps);
00158 
00159             fourxm->video_stream_index = st->index;
00160 
00161             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00162             st->codec->codec_id = AV_CODEC_ID_4XM;
00163             st->codec->extradata_size = 4;
00164             st->codec->extradata = av_malloc(4);
00165             AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16]));
00166             st->codec->width  = fourxm->width;
00167             st->codec->height = fourxm->height;
00168 
00169             i += 8 + size;
00170         } else if (fourcc_tag == strk_TAG) {
00171             int current_track;
00172             /* check that there is enough data */
00173             if (size != strk_SIZE) {
00174                 ret= AVERROR_INVALIDDATA;
00175                 goto fail;
00176             }
00177             current_track = AV_RL32(&header[i + 8]);
00178             if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){
00179                 av_log(s, AV_LOG_ERROR, "current_track too large\n");
00180                 ret = AVERROR_INVALIDDATA;
00181                 goto fail;
00182             }
00183             if (current_track + 1 > fourxm->track_count) {
00184                 fourxm->tracks = av_realloc_f(fourxm->tracks,
00185                                               sizeof(AudioTrack),
00186                                               current_track + 1);
00187                 if (!fourxm->tracks) {
00188                     ret = AVERROR(ENOMEM);
00189                     goto fail;
00190                 }
00191                 memset(&fourxm->tracks[fourxm->track_count], 0,
00192                        sizeof(AudioTrack) * (current_track + 1 - fourxm->track_count));
00193                 fourxm->track_count = current_track + 1;
00194             }
00195             fourxm->tracks[current_track].adpcm       = AV_RL32(&header[i + 12]);
00196             fourxm->tracks[current_track].channels    = AV_RL32(&header[i + 36]);
00197             fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]);
00198             fourxm->tracks[current_track].bits        = AV_RL32(&header[i + 44]);
00199             fourxm->tracks[current_track].audio_pts   = 0;
00200             if(   fourxm->tracks[current_track].channels    <= 0
00201                || fourxm->tracks[current_track].sample_rate <= 0
00202                || fourxm->tracks[current_track].bits        <  0){
00203                 av_log(s, AV_LOG_ERROR, "audio header invalid\n");
00204                 ret = AVERROR_INVALIDDATA;
00205                 goto fail;
00206             }
00207             if(!fourxm->tracks[current_track].adpcm && fourxm->tracks[current_track].bits<8){
00208                 av_log(s, AV_LOG_ERROR, "bits unspecified for non ADPCM\n");
00209                 ret = AVERROR_INVALIDDATA;
00210                 goto fail;
00211             }
00212             i += 8 + size;
00213 
00214             /* allocate a new AVStream */
00215             st = avformat_new_stream(s, NULL);
00216             if (!st){
00217                 ret= AVERROR(ENOMEM);
00218                 goto fail;
00219             }
00220 
00221             st->id = current_track;
00222             avpriv_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
00223 
00224             fourxm->tracks[current_track].stream_index = st->index;
00225 
00226             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00227             st->codec->codec_tag = 0;
00228             st->codec->channels              = fourxm->tracks[current_track].channels;
00229             st->codec->sample_rate           = fourxm->tracks[current_track].sample_rate;
00230             st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
00231             st->codec->bit_rate              = st->codec->channels * st->codec->sample_rate *
00232                 st->codec->bits_per_coded_sample;
00233             st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00234             if (fourxm->tracks[current_track].adpcm){
00235                 st->codec->codec_id = AV_CODEC_ID_ADPCM_4XM;
00236             }else if (st->codec->bits_per_coded_sample == 8){
00237                 st->codec->codec_id = AV_CODEC_ID_PCM_U8;
00238             }else
00239                 st->codec->codec_id = AV_CODEC_ID_PCM_S16LE;
00240         }
00241     }
00242 
00243     /* skip over the LIST-MOVI chunk (which is where the stream should be */
00244     GET_LIST_HEADER();
00245     if (fourcc_tag != MOVI_TAG){
00246         ret= AVERROR_INVALIDDATA;
00247         goto fail;
00248     }
00249 
00250     av_free(header);
00251     /* initialize context members */
00252     fourxm->video_pts = -1;  /* first frame will push to 0 */
00253 
00254     return 0;
00255 fail:
00256     av_freep(&fourxm->tracks);
00257     av_free(header);
00258     return ret;
00259 }
00260 
00261 static int fourxm_read_packet(AVFormatContext *s,
00262                               AVPacket *pkt)
00263 {
00264     FourxmDemuxContext *fourxm = s->priv_data;
00265     AVIOContext *pb = s->pb;
00266     unsigned int fourcc_tag;
00267     unsigned int size;
00268     int ret = 0;
00269     unsigned int track_number;
00270     int packet_read = 0;
00271     unsigned char header[8];
00272     int audio_frame_count;
00273 
00274     while (!packet_read) {
00275 
00276         if ((ret = avio_read(s->pb, header, 8)) < 0)
00277             return ret;
00278         fourcc_tag = AV_RL32(&header[0]);
00279         size = AV_RL32(&header[4]);
00280         if (url_feof(pb))
00281             return AVERROR(EIO);
00282         switch (fourcc_tag) {
00283 
00284         case LIST_TAG:
00285             /* this is a good time to bump the video pts */
00286             fourxm->video_pts ++;
00287 
00288             /* skip the LIST-* tag and move on to the next fourcc */
00289             avio_rl32(pb);
00290             break;
00291 
00292         case ifrm_TAG:
00293         case pfrm_TAG:
00294         case cfrm_TAG:
00295         case ifr2_TAG:
00296         case pfr2_TAG:
00297         case cfr2_TAG:
00298             /* allocate 8 more bytes than 'size' to account for fourcc
00299              * and size */
00300             if (size + 8 < size || av_new_packet(pkt, size + 8))
00301                 return AVERROR(EIO);
00302             pkt->stream_index = fourxm->video_stream_index;
00303             pkt->pts = fourxm->video_pts;
00304             pkt->pos = avio_tell(s->pb);
00305             memcpy(pkt->data, header, 8);
00306             ret = avio_read(s->pb, &pkt->data[8], size);
00307 
00308             if (ret < 0){
00309                 av_free_packet(pkt);
00310             }else
00311                 packet_read = 1;
00312             break;
00313 
00314         case snd__TAG:
00315             track_number = avio_rl32(pb);
00316             avio_skip(pb, 4);
00317             size-=8;
00318 
00319             if (track_number < fourxm->track_count && fourxm->tracks[track_number].channels>0) {
00320                 ret= av_get_packet(s->pb, pkt, size);
00321                 if(ret<0)
00322                     return AVERROR(EIO);
00323                 pkt->stream_index =
00324                     fourxm->tracks[track_number].stream_index;
00325                 pkt->pts = fourxm->tracks[track_number].audio_pts;
00326                 packet_read = 1;
00327 
00328                 /* pts accounting */
00329                 audio_frame_count = size;
00330                 if (fourxm->tracks[track_number].adpcm)
00331                     audio_frame_count -=
00332                         2 * (fourxm->tracks[track_number].channels);
00333                 audio_frame_count /=
00334                       fourxm->tracks[track_number].channels;
00335                 if (fourxm->tracks[track_number].adpcm){
00336                     audio_frame_count *= 2;
00337                 }else
00338                     audio_frame_count /=
00339                     (fourxm->tracks[track_number].bits / 8);
00340                 fourxm->tracks[track_number].audio_pts += audio_frame_count;
00341 
00342             } else {
00343                 avio_skip(pb, size);
00344             }
00345             break;
00346 
00347         default:
00348             avio_skip(pb, size);
00349             break;
00350         }
00351     }
00352     return ret;
00353 }
00354 
00355 static int fourxm_read_close(AVFormatContext *s)
00356 {
00357     FourxmDemuxContext *fourxm = s->priv_data;
00358 
00359     av_freep(&fourxm->tracks);
00360 
00361     return 0;
00362 }
00363 
00364 AVInputFormat ff_fourxm_demuxer = {
00365     .name           = "4xm",
00366     .long_name      = NULL_IF_CONFIG_SMALL("4X Technologies"),
00367     .priv_data_size = sizeof(FourxmDemuxContext),
00368     .read_probe     = fourxm_probe,
00369     .read_header    = fourxm_read_header,
00370     .read_packet    = fourxm_read_packet,
00371     .read_close     = fourxm_read_close,
00372 };