1/* 2 * 4X Technologies .4xm File Demuxer (no muxer) 3 * Copyright (c) 2003 The ffmpeg Project 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * 4X Technologies file demuxer 25 * by Mike Melanson (melanson@pcisys.net) 26 * for more information on the .4xm file format, visit: 27 * http://www.pcisys.net/~melanson/codecs/ 28 */ 29 30#include "libavutil/intreadwrite.h" 31#include "avformat.h" 32 33#define RIFF_TAG MKTAG('R', 'I', 'F', 'F') 34#define FOURXMV_TAG MKTAG('4', 'X', 'M', 'V') 35#define LIST_TAG MKTAG('L', 'I', 'S', 'T') 36#define HEAD_TAG MKTAG('H', 'E', 'A', 'D') 37#define TRK__TAG MKTAG('T', 'R', 'K', '_') 38#define MOVI_TAG MKTAG('M', 'O', 'V', 'I') 39#define VTRK_TAG MKTAG('V', 'T', 'R', 'K') 40#define STRK_TAG MKTAG('S', 'T', 'R', 'K') 41#define std__TAG MKTAG('s', 't', 'd', '_') 42#define name_TAG MKTAG('n', 'a', 'm', 'e') 43#define vtrk_TAG MKTAG('v', 't', 'r', 'k') 44#define strk_TAG MKTAG('s', 't', 'r', 'k') 45#define ifrm_TAG MKTAG('i', 'f', 'r', 'm') 46#define pfrm_TAG MKTAG('p', 'f', 'r', 'm') 47#define cfrm_TAG MKTAG('c', 'f', 'r', 'm') 48#define ifr2_TAG MKTAG('i', 'f', 'r', '2') 49#define pfr2_TAG MKTAG('p', 'f', 'r', '2') 50#define cfr2_TAG MKTAG('c', 'f', 'r', '2') 51#define snd__TAG MKTAG('s', 'n', 'd', '_') 52 53#define vtrk_SIZE 0x44 54#define strk_SIZE 0x28 55 56#define GET_LIST_HEADER() \ 57 fourcc_tag = get_le32(pb); \ 58 size = get_le32(pb); \ 59 if (fourcc_tag != LIST_TAG) \ 60 return AVERROR_INVALIDDATA; \ 61 fourcc_tag = get_le32(pb); 62 63typedef struct AudioTrack { 64 int sample_rate; 65 int bits; 66 int channels; 67 int stream_index; 68 int adpcm; 69 int64_t audio_pts; 70} AudioTrack; 71 72typedef struct FourxmDemuxContext { 73 int width; 74 int height; 75 int video_stream_index; 76 int track_count; 77 AudioTrack *tracks; 78 79 int64_t video_pts; 80 float fps; 81} FourxmDemuxContext; 82 83static int fourxm_probe(AVProbeData *p) 84{ 85 if ((AV_RL32(&p->buf[0]) != RIFF_TAG) || 86 (AV_RL32(&p->buf[8]) != FOURXMV_TAG)) 87 return 0; 88 89 return AVPROBE_SCORE_MAX; 90} 91 92static int fourxm_read_header(AVFormatContext *s, 93 AVFormatParameters *ap) 94{ 95 ByteIOContext *pb = s->pb; 96 unsigned int fourcc_tag; 97 unsigned int size; 98 int header_size; 99 FourxmDemuxContext *fourxm = s->priv_data; 100 unsigned char *header; 101 int i, ret; 102 AVStream *st; 103 104 fourxm->track_count = 0; 105 fourxm->tracks = NULL; 106 fourxm->fps = 1.0; 107 108 /* skip the first 3 32-bit numbers */ 109 url_fseek(pb, 12, SEEK_CUR); 110 111 /* check for LIST-HEAD */ 112 GET_LIST_HEADER(); 113 header_size = size - 4; 114 if (fourcc_tag != HEAD_TAG || header_size < 0) 115 return AVERROR_INVALIDDATA; 116 117 /* allocate space for the header and load the whole thing */ 118 header = av_malloc(header_size); 119 if (!header) 120 return AVERROR(ENOMEM); 121 if (get_buffer(pb, header, header_size) != header_size){ 122 av_free(header); 123 return AVERROR(EIO); 124 } 125 126 /* take the lazy approach and search for any and all vtrk and strk chunks */ 127 for (i = 0; i < header_size - 8; i++) { 128 fourcc_tag = AV_RL32(&header[i]); 129 size = AV_RL32(&header[i + 4]); 130 131 if (fourcc_tag == std__TAG) { 132 fourxm->fps = av_int2flt(AV_RL32(&header[i + 12])); 133 } else if (fourcc_tag == vtrk_TAG) { 134 /* check that there is enough data */ 135 if (size != vtrk_SIZE) { 136 ret= AVERROR_INVALIDDATA; 137 goto fail; 138 } 139 fourxm->width = AV_RL32(&header[i + 36]); 140 fourxm->height = AV_RL32(&header[i + 40]); 141 142 /* allocate a new AVStream */ 143 st = av_new_stream(s, 0); 144 if (!st){ 145 ret= AVERROR(ENOMEM); 146 goto fail; 147 } 148 av_set_pts_info(st, 60, 1, fourxm->fps); 149 150 fourxm->video_stream_index = st->index; 151 152 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 153 st->codec->codec_id = CODEC_ID_4XM; 154 st->codec->extradata_size = 4; 155 st->codec->extradata = av_malloc(4); 156 AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16])); 157 st->codec->width = fourxm->width; 158 st->codec->height = fourxm->height; 159 160 i += 8 + size; 161 } else if (fourcc_tag == strk_TAG) { 162 int current_track; 163 /* check that there is enough data */ 164 if (size != strk_SIZE) { 165 ret= AVERROR_INVALIDDATA; 166 goto fail; 167 } 168 current_track = AV_RL32(&header[i + 8]); 169 if((unsigned)current_track >= UINT_MAX / sizeof(AudioTrack) - 1){ 170 av_log(s, AV_LOG_ERROR, "current_track too large\n"); 171 ret= -1; 172 goto fail; 173 } 174 if (current_track + 1 > fourxm->track_count) { 175 fourxm->track_count = current_track + 1; 176 fourxm->tracks = av_realloc(fourxm->tracks, 177 fourxm->track_count * sizeof(AudioTrack)); 178 if (!fourxm->tracks) { 179 ret= AVERROR(ENOMEM); 180 goto fail; 181 } 182 } 183 fourxm->tracks[current_track].adpcm = AV_RL32(&header[i + 12]); 184 fourxm->tracks[current_track].channels = AV_RL32(&header[i + 36]); 185 fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]); 186 fourxm->tracks[current_track].bits = AV_RL32(&header[i + 44]); 187 fourxm->tracks[current_track].audio_pts = 0; 188 i += 8 + size; 189 190 /* allocate a new AVStream */ 191 st = av_new_stream(s, current_track); 192 if (!st){ 193 ret= AVERROR(ENOMEM); 194 goto fail; 195 } 196 197 av_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate); 198 199 fourxm->tracks[current_track].stream_index = st->index; 200 201 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 202 st->codec->codec_tag = 0; 203 st->codec->channels = fourxm->tracks[current_track].channels; 204 st->codec->sample_rate = fourxm->tracks[current_track].sample_rate; 205 st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits; 206 st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * 207 st->codec->bits_per_coded_sample; 208 st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample; 209 if (fourxm->tracks[current_track].adpcm){ 210 st->codec->codec_id = CODEC_ID_ADPCM_4XM; 211 }else if (st->codec->bits_per_coded_sample == 8){ 212 st->codec->codec_id = CODEC_ID_PCM_U8; 213 }else 214 st->codec->codec_id = CODEC_ID_PCM_S16LE; 215 } 216 } 217 218 /* skip over the LIST-MOVI chunk (which is where the stream should be */ 219 GET_LIST_HEADER(); 220 if (fourcc_tag != MOVI_TAG){ 221 ret= AVERROR_INVALIDDATA; 222 goto fail; 223 } 224 225 av_free(header); 226 /* initialize context members */ 227 fourxm->video_pts = -1; /* first frame will push to 0 */ 228 229 return 0; 230fail: 231 av_freep(&fourxm->tracks); 232 av_free(header); 233 return ret; 234} 235 236static int fourxm_read_packet(AVFormatContext *s, 237 AVPacket *pkt) 238{ 239 FourxmDemuxContext *fourxm = s->priv_data; 240 ByteIOContext *pb = s->pb; 241 unsigned int fourcc_tag; 242 unsigned int size, out_size; 243 int ret = 0; 244 unsigned int track_number; 245 int packet_read = 0; 246 unsigned char header[8]; 247 int audio_frame_count; 248 249 while (!packet_read) { 250 251 if ((ret = get_buffer(s->pb, header, 8)) < 0) 252 return ret; 253 fourcc_tag = AV_RL32(&header[0]); 254 size = AV_RL32(&header[4]); 255 if (url_feof(pb)) 256 return AVERROR(EIO); 257 switch (fourcc_tag) { 258 259 case LIST_TAG: 260 /* this is a good time to bump the video pts */ 261 fourxm->video_pts ++; 262 263 /* skip the LIST-* tag and move on to the next fourcc */ 264 get_le32(pb); 265 break; 266 267 case ifrm_TAG: 268 case pfrm_TAG: 269 case cfrm_TAG: 270 case ifr2_TAG: 271 case pfr2_TAG: 272 case cfr2_TAG: 273 /* allocate 8 more bytes than 'size' to account for fourcc 274 * and size */ 275 if (size + 8 < size || av_new_packet(pkt, size + 8)) 276 return AVERROR(EIO); 277 pkt->stream_index = fourxm->video_stream_index; 278 pkt->pts = fourxm->video_pts; 279 pkt->pos = url_ftell(s->pb); 280 memcpy(pkt->data, header, 8); 281 ret = get_buffer(s->pb, &pkt->data[8], size); 282 283 if (ret < 0){ 284 av_free_packet(pkt); 285 }else 286 packet_read = 1; 287 break; 288 289 case snd__TAG: 290 track_number = get_le32(pb); 291 out_size= get_le32(pb); 292 size-=8; 293 294 if (track_number < fourxm->track_count) { 295 ret= av_get_packet(s->pb, pkt, size); 296 if(ret<0) 297 return AVERROR(EIO); 298 pkt->stream_index = 299 fourxm->tracks[track_number].stream_index; 300 pkt->pts = fourxm->tracks[track_number].audio_pts; 301 packet_read = 1; 302 303 /* pts accounting */ 304 audio_frame_count = size; 305 if (fourxm->tracks[track_number].adpcm) 306 audio_frame_count -= 307 2 * (fourxm->tracks[track_number].channels); 308 audio_frame_count /= 309 fourxm->tracks[track_number].channels; 310 if (fourxm->tracks[track_number].adpcm){ 311 audio_frame_count *= 2; 312 }else 313 audio_frame_count /= 314 (fourxm->tracks[track_number].bits / 8); 315 fourxm->tracks[track_number].audio_pts += audio_frame_count; 316 317 } else { 318 url_fseek(pb, size, SEEK_CUR); 319 } 320 break; 321 322 default: 323 url_fseek(pb, size, SEEK_CUR); 324 break; 325 } 326 } 327 return ret; 328} 329 330static int fourxm_read_close(AVFormatContext *s) 331{ 332 FourxmDemuxContext *fourxm = s->priv_data; 333 334 av_freep(&fourxm->tracks); 335 336 return 0; 337} 338 339AVInputFormat fourxm_demuxer = { 340 "4xm", 341 NULL_IF_CONFIG_SMALL("4X Technologies format"), 342 sizeof(FourxmDemuxContext), 343 fourxm_probe, 344 fourxm_read_header, 345 fourxm_read_packet, 346 fourxm_read_close, 347}; 348