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_readwrite.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_int2flt(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_f(fourxm->tracks,
00178                                               sizeof(AudioTrack),
00179                                               current_track + 1);
00180                 if (!fourxm->tracks) {
00181                     ret = AVERROR(ENOMEM);
00182                     goto fail;
00183                 }
00184                 memset(&fourxm->tracks[fourxm->track_count], 0,
00185                        sizeof(AudioTrack) * (current_track + 1 - fourxm->track_count));
00186                 fourxm->track_count = current_track + 1;
00187             }
00188             fourxm->tracks[current_track].adpcm       = AV_RL32(&header[i + 12]);
00189             fourxm->tracks[current_track].channels    = AV_RL32(&header[i + 36]);
00190             fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]);
00191             fourxm->tracks[current_track].bits        = AV_RL32(&header[i + 44]);
00192             fourxm->tracks[current_track].audio_pts   = 0;
00193             if(   fourxm->tracks[current_track].channels    <= 0
00194                || fourxm->tracks[current_track].sample_rate <= 0
00195                || fourxm->tracks[current_track].bits        <  0){
00196                 av_log(s, AV_LOG_ERROR, "audio header invalid\n");
00197                 ret= -1;
00198                 goto fail;
00199             }
00200             i += 8 + size;
00201 
00202             /* allocate a new AVStream */
00203             st = avformat_new_stream(s, NULL);
00204             if (!st){
00205                 ret= AVERROR(ENOMEM);
00206                 goto fail;
00207             }
00208 
00209             st->id = current_track;
00210             avpriv_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
00211 
00212             fourxm->tracks[current_track].stream_index = st->index;
00213 
00214             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00215             st->codec->codec_tag = 0;
00216             st->codec->channels              = fourxm->tracks[current_track].channels;
00217             st->codec->sample_rate           = fourxm->tracks[current_track].sample_rate;
00218             st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
00219             st->codec->bit_rate              = st->codec->channels * st->codec->sample_rate *
00220                 st->codec->bits_per_coded_sample;
00221             st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00222             if (fourxm->tracks[current_track].adpcm){
00223                 st->codec->codec_id = CODEC_ID_ADPCM_4XM;
00224             }else if (st->codec->bits_per_coded_sample == 8){
00225                 st->codec->codec_id = CODEC_ID_PCM_U8;
00226             }else
00227                 st->codec->codec_id = CODEC_ID_PCM_S16LE;
00228         }
00229     }
00230 
00231     /* skip over the LIST-MOVI chunk (which is where the stream should be */
00232     GET_LIST_HEADER();
00233     if (fourcc_tag != MOVI_TAG){
00234         ret= AVERROR_INVALIDDATA;
00235         goto fail;
00236     }
00237 
00238     av_free(header);
00239     /* initialize context members */
00240     fourxm->video_pts = -1;  /* first frame will push to 0 */
00241 
00242     return 0;
00243 fail:
00244     av_freep(&fourxm->tracks);
00245     av_free(header);
00246     return ret;
00247 }
00248 
00249 static int fourxm_read_packet(AVFormatContext *s,
00250                               AVPacket *pkt)
00251 {
00252     FourxmDemuxContext *fourxm = s->priv_data;
00253     AVIOContext *pb = s->pb;
00254     unsigned int fourcc_tag;
00255     unsigned int size;
00256     int ret = 0;
00257     unsigned int track_number;
00258     int packet_read = 0;
00259     unsigned char header[8];
00260     int audio_frame_count;
00261 
00262     while (!packet_read) {
00263 
00264         if ((ret = avio_read(s->pb, header, 8)) < 0)
00265             return ret;
00266         fourcc_tag = AV_RL32(&header[0]);
00267         size = AV_RL32(&header[4]);
00268         if (url_feof(pb))
00269             return AVERROR(EIO);
00270         switch (fourcc_tag) {
00271 
00272         case LIST_TAG:
00273             /* this is a good time to bump the video pts */
00274             fourxm->video_pts ++;
00275 
00276             /* skip the LIST-* tag and move on to the next fourcc */
00277             avio_rl32(pb);
00278             break;
00279 
00280         case ifrm_TAG:
00281         case pfrm_TAG:
00282         case cfrm_TAG:
00283         case ifr2_TAG:
00284         case pfr2_TAG:
00285         case cfr2_TAG:
00286             /* allocate 8 more bytes than 'size' to account for fourcc
00287              * and size */
00288             if (size + 8 < size || av_new_packet(pkt, size + 8))
00289                 return AVERROR(EIO);
00290             pkt->stream_index = fourxm->video_stream_index;
00291             pkt->pts = fourxm->video_pts;
00292             pkt->pos = avio_tell(s->pb);
00293             memcpy(pkt->data, header, 8);
00294             ret = avio_read(s->pb, &pkt->data[8], size);
00295 
00296             if (ret < 0){
00297                 av_free_packet(pkt);
00298             }else
00299                 packet_read = 1;
00300             break;
00301 
00302         case snd__TAG:
00303             track_number = avio_rl32(pb);
00304             avio_skip(pb, 4);
00305             size-=8;
00306 
00307             if (track_number < fourxm->track_count && fourxm->tracks[track_number].channels>0) {
00308                 ret= av_get_packet(s->pb, pkt, size);
00309                 if(ret<0)
00310                     return AVERROR(EIO);
00311                 pkt->stream_index =
00312                     fourxm->tracks[track_number].stream_index;
00313                 pkt->pts = fourxm->tracks[track_number].audio_pts;
00314                 packet_read = 1;
00315 
00316                 /* pts accounting */
00317                 audio_frame_count = size;
00318                 if (fourxm->tracks[track_number].adpcm)
00319                     audio_frame_count -=
00320                         2 * (fourxm->tracks[track_number].channels);
00321                 audio_frame_count /=
00322                       fourxm->tracks[track_number].channels;
00323                 if (fourxm->tracks[track_number].adpcm){
00324                     audio_frame_count *= 2;
00325                 }else
00326                     audio_frame_count /=
00327                     (fourxm->tracks[track_number].bits / 8);
00328                 fourxm->tracks[track_number].audio_pts += audio_frame_count;
00329 
00330             } else {
00331                 avio_skip(pb, size);
00332             }
00333             break;
00334 
00335         default:
00336             avio_skip(pb, size);
00337             break;
00338         }
00339     }
00340     return ret;
00341 }
00342 
00343 static int fourxm_read_close(AVFormatContext *s)
00344 {
00345     FourxmDemuxContext *fourxm = s->priv_data;
00346 
00347     av_freep(&fourxm->tracks);
00348 
00349     return 0;
00350 }
00351 
00352 AVInputFormat ff_fourxm_demuxer = {
00353     .name           = "4xm",
00354     .long_name      = NULL_IF_CONFIG_SMALL("4X Technologies format"),
00355     .priv_data_size = sizeof(FourxmDemuxContext),
00356     .read_probe     = fourxm_probe,
00357     .read_header    = fourxm_read_header,
00358     .read_packet    = fourxm_read_packet,
00359     .read_close     = fourxm_read_close,
00360 };