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 "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 = get_le32(pb); \
00058     size = get_le32(pb); \
00059     if (fourcc_tag != LIST_TAG) \
00060         return AVERROR_INVALIDDATA; \
00061     fourcc_tag = get_le32(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     ByteIOContext *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     url_fseek(pb, 12, SEEK_CUR);
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 (get_buffer(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         if (size > header_size - i - 8 && (fourcc_tag == vtrk_TAG || fourcc_tag == strk_TAG)) {
00131             av_log(s, AV_LOG_ERROR, "chunk larger than array %d>%d\n", size, header_size - i - 8);
00132             return AVERROR_INVALIDDATA;
00133         }
00134 
00135         if (fourcc_tag == std__TAG) {
00136             fourxm->fps = av_int2flt(AV_RL32(&header[i + 12]));
00137         } else if (fourcc_tag == vtrk_TAG) {
00138             /* check that there is enough data */
00139             if (size != vtrk_SIZE) {
00140                 ret= AVERROR_INVALIDDATA;
00141                 goto fail;
00142             }
00143             fourxm->width  = AV_RL32(&header[i + 36]);
00144             fourxm->height = AV_RL32(&header[i + 40]);
00145 
00146             /* allocate a new AVStream */
00147             st = av_new_stream(s, 0);
00148             if (!st){
00149                 ret= AVERROR(ENOMEM);
00150                 goto fail;
00151             }
00152             av_set_pts_info(st, 60, 1, fourxm->fps);
00153 
00154             fourxm->video_stream_index = st->index;
00155 
00156             st->codec->codec_type = CODEC_TYPE_VIDEO;
00157             st->codec->codec_id = CODEC_ID_4XM;
00158             st->codec->extradata_size = 4;
00159             st->codec->extradata = av_malloc(4);
00160             AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16]));
00161             st->codec->width  = fourxm->width;
00162             st->codec->height = fourxm->height;
00163 
00164             i += 8 + size;
00165         } else if (fourcc_tag == strk_TAG) {
00166             int current_track;
00167             /* check that there is enough data */
00168             if (size != strk_SIZE) {
00169                 ret= AVERROR_INVALIDDATA;
00170                 goto fail;
00171             }
00172             current_track = AV_RL32(&header[i + 8]);
00173             if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){
00174                 av_log(s, AV_LOG_ERROR, "current_track too large\n");
00175                 ret= -1;
00176                 goto fail;
00177             }
00178             if (current_track + 1 > fourxm->track_count) {
00179                 fourxm->track_count = current_track + 1;
00180                 fourxm->tracks = av_realloc(fourxm->tracks,
00181                     fourxm->track_count * sizeof(AudioTrack));
00182                 if (!fourxm->tracks) {
00183                     ret=  AVERROR(ENOMEM);
00184                     goto fail;
00185                 }
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             i += 8 + size;
00193 
00194             /* allocate a new AVStream */
00195             st = av_new_stream(s, current_track);
00196             if (!st){
00197                 ret= AVERROR(ENOMEM);
00198                 goto fail;
00199             }
00200 
00201             av_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
00202 
00203             fourxm->tracks[current_track].stream_index = st->index;
00204 
00205             st->codec->codec_type = CODEC_TYPE_AUDIO;
00206             st->codec->codec_tag = 0;
00207             st->codec->channels              = fourxm->tracks[current_track].channels;
00208             st->codec->sample_rate           = fourxm->tracks[current_track].sample_rate;
00209             st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
00210             st->codec->bit_rate              = st->codec->channels * st->codec->sample_rate *
00211                 st->codec->bits_per_coded_sample;
00212             st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
00213             if (fourxm->tracks[current_track].adpcm){
00214                 st->codec->codec_id = CODEC_ID_ADPCM_4XM;
00215             }else if (st->codec->bits_per_coded_sample == 8){
00216                 st->codec->codec_id = CODEC_ID_PCM_U8;
00217             }else
00218                 st->codec->codec_id = CODEC_ID_PCM_S16LE;
00219         }
00220     }
00221 
00222     /* skip over the LIST-MOVI chunk (which is where the stream should be */
00223     GET_LIST_HEADER();
00224     if (fourcc_tag != MOVI_TAG){
00225         ret= AVERROR_INVALIDDATA;
00226         goto fail;
00227     }
00228 
00229     av_free(header);
00230     /* initialize context members */
00231     fourxm->video_pts = -1;  /* first frame will push to 0 */
00232 
00233     return 0;
00234 fail:
00235     av_freep(&fourxm->tracks);
00236     av_free(header);
00237     return ret;
00238 }
00239 
00240 static int fourxm_read_packet(AVFormatContext *s,
00241                               AVPacket *pkt)
00242 {
00243     FourxmDemuxContext *fourxm = s->priv_data;
00244     ByteIOContext *pb = s->pb;
00245     unsigned int fourcc_tag;
00246     unsigned int size, out_size;
00247     int ret = 0;
00248     unsigned int track_number;
00249     int packet_read = 0;
00250     unsigned char header[8];
00251     int audio_frame_count;
00252 
00253     while (!packet_read) {
00254 
00255         if ((ret = get_buffer(s->pb, header, 8)) < 0)
00256             return ret;
00257         fourcc_tag = AV_RL32(&header[0]);
00258         size = AV_RL32(&header[4]);
00259         if (url_feof(pb))
00260             return AVERROR(EIO);
00261         switch (fourcc_tag) {
00262 
00263         case LIST_TAG:
00264             /* this is a good time to bump the video pts */
00265             fourxm->video_pts ++;
00266 
00267             /* skip the LIST-* tag and move on to the next fourcc */
00268             get_le32(pb);
00269             break;
00270 
00271         case ifrm_TAG:
00272         case pfrm_TAG:
00273         case cfrm_TAG:
00274         case ifr2_TAG:
00275         case pfr2_TAG:
00276         case cfr2_TAG:
00277             /* allocate 8 more bytes than 'size' to account for fourcc
00278              * and size */
00279             if (size + 8 < size || av_new_packet(pkt, size + 8))
00280                 return AVERROR(EIO);
00281             pkt->stream_index = fourxm->video_stream_index;
00282             pkt->pts = fourxm->video_pts;
00283             pkt->pos = url_ftell(s->pb);
00284             memcpy(pkt->data, header, 8);
00285             ret = get_buffer(s->pb, &pkt->data[8], size);
00286 
00287             if (ret < 0){
00288                 av_free_packet(pkt);
00289             }else
00290                 packet_read = 1;
00291             break;
00292 
00293         case snd__TAG:
00294             track_number = get_le32(pb);
00295             out_size= get_le32(pb);
00296             size-=8;
00297 
00298             if (track_number < fourxm->track_count) {
00299                 ret= av_get_packet(s->pb, pkt, size);
00300                 if(ret<0)
00301                     return AVERROR(EIO);
00302                 pkt->stream_index =
00303                     fourxm->tracks[track_number].stream_index;
00304                 pkt->pts = fourxm->tracks[track_number].audio_pts;
00305                 packet_read = 1;
00306 
00307                 /* pts accounting */
00308                 audio_frame_count = size;
00309                 if (fourxm->tracks[track_number].adpcm)
00310                     audio_frame_count -=
00311                         2 * (fourxm->tracks[track_number].channels);
00312                 audio_frame_count /=
00313                       fourxm->tracks[track_number].channels;
00314                 if (fourxm->tracks[track_number].adpcm){
00315                     audio_frame_count *= 2;
00316                 }else
00317                     audio_frame_count /=
00318                     (fourxm->tracks[track_number].bits / 8);
00319                 fourxm->tracks[track_number].audio_pts += audio_frame_count;
00320 
00321             } else {
00322                 url_fseek(pb, size, SEEK_CUR);
00323             }
00324             break;
00325 
00326         default:
00327             url_fseek(pb, size, SEEK_CUR);
00328             break;
00329         }
00330     }
00331     return ret;
00332 }
00333 
00334 static int fourxm_read_close(AVFormatContext *s)
00335 {
00336     FourxmDemuxContext *fourxm = s->priv_data;
00337 
00338     av_freep(&fourxm->tracks);
00339 
00340     return 0;
00341 }
00342 
00343 AVInputFormat fourxm_demuxer = {
00344     "4xm",
00345     NULL_IF_CONFIG_SMALL("4X Technologies format"),
00346     sizeof(FourxmDemuxContext),
00347     fourxm_probe,
00348     fourxm_read_header,
00349     fourxm_read_packet,
00350     fourxm_read_close,
00351 };