FFmpeg: libavformat/4xm.c Source File

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libavformat

4xm.c

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1 /*

2 * 4X Technologies .4xm File Demuxer (no muxer)

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 */

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 */

30 #include "libavutil/intreadwrite.h"

31 #include "libavutil/intfloat.h"

32 #include "avformat.h"

33 #include "internal.h"

35 #define RIFF_TAG MKTAG('R', 'I', 'F', 'F')

36 #define FOURXMV_TAG MKTAG('4', 'X', 'M', 'V')

37 #define LIST_TAG MKTAG('L', 'I', 'S', 'T')

38 #define HEAD_TAG MKTAG('H', 'E', 'A', 'D')

39 #define TRK__TAG MKTAG('T', 'R', 'K', '_')

40 #define MOVI_TAG MKTAG('M', 'O', 'V', 'I')

41 #define VTRK_TAG MKTAG('V', 'T', 'R', 'K')

42 #define STRK_TAG MKTAG('S', 'T', 'R', 'K')

43 #define std__TAG MKTAG('s', 't', 'd', '_')

44 #define name_TAG MKTAG('n', 'a', 'm', 'e')

45 #define vtrk_TAG MKTAG('v', 't', 'r', 'k')

46 #define strk_TAG MKTAG('s', 't', 'r', 'k')

47 #define ifrm_TAG MKTAG('i', 'f', 'r', 'm')

48 #define pfrm_TAG MKTAG('p', 'f', 'r', 'm')

49 #define cfrm_TAG MKTAG('c', 'f', 'r', 'm')

50 #define ifr2_TAG MKTAG('i', 'f', 'r', '2')

51 #define pfr2_TAG MKTAG('p', 'f', 'r', '2')

52 #define cfr2_TAG MKTAG('c', 'f', 'r', '2')

53 #define snd__TAG MKTAG('s', 'n', 'd', '_')

55 #define vtrk_SIZE 0x44

56 #define strk_SIZE 0x28

58 #define GET_LIST_HEADER() \

59 fourcc_tag = avio_rl32(pb); \

60 size = avio_rl32(pb); \

61 if (fourcc_tag != LIST_TAG) \

62 return AVERROR_INVALIDDATA; \

63 fourcc_tag = avio_rl32(pb);

65 typedef struct AudioTrack {

66 int sample_rate;

67 int bits;

68 int channels;

69 int stream_index;

70 int adpcm;

71 int64_t audio_pts;

72 } AudioTrack;

74 typedef struct FourxmDemuxContext {

75 int video_stream_index;

76 int track_count;

77 AudioTrack *tracks;

79 int64_t video_pts;

80 float fps;

81 } FourxmDemuxContext;

83 static 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;

89 return AVPROBE_SCORE_MAX;

90 }

92 static int parse_vtrk(AVFormatContext *s,

93 FourxmDemuxContext *fourxm, uint8_t *buf, int size,

94 int left)

95 {

96 AVStream *st;

97 /* check that there is enough data */

98 if (size != vtrk_SIZE || left < size + 8) {

99 return AVERROR_INVALIDDATA;

100 }

101

102 /* allocate a new AVStream */

103 st = avformat_new_stream(s, NULL);

104 if (!st)

105 return AVERROR(ENOMEM);

106

107 avpriv_set_pts_info(st, 60, 1, fourxm->fps);

108

109 fourxm->video_stream_index = st->index;

110

111 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

112 st->codec->codec_id = AV_CODEC_ID_4XM;

113

114 st->codec->extradata = av_mallocz(4 + FF_INPUT_BUFFER_PADDING_SIZE);

115 if (!st->codec->extradata)

116 return AVERROR(ENOMEM);

117 st->codec->extradata_size = 4;

118 AV_WL32(st->codec->extradata, AV_RL32(buf + 16));

119 st->codec->width = AV_RL32(buf + 36);

120 st->codec->height = AV_RL32(buf + 40);

121

122 return 0;

123 }

124

125

126 static int parse_strk(AVFormatContext *s,

127 FourxmDemuxContext *fourxm, uint8_t *buf, int size,

128 int left)

129 {

130 AVStream *st;

131 int track;

132 /* check that there is enough data */

133 if (size != strk_SIZE || left < size + 8)

134 return AVERROR_INVALIDDATA;

135

136 track = AV_RL32(buf + 8);

137 if ((unsigned)track >= UINT_MAX / sizeof(AudioTrack) - 1) {

138 av_log(s, AV_LOG_ERROR, "current_track too large\n");

139 return AVERROR_INVALIDDATA;

140 }

141

142 if (track + 1 > fourxm->track_count) {

143 if (av_reallocp_array(&fourxm->tracks, track + 1, sizeof(AudioTrack)))

144 return AVERROR(ENOMEM);

145 memset(&fourxm->tracks[fourxm->track_count], 0,

146 sizeof(AudioTrack) * (track + 1 - fourxm->track_count));

147 fourxm->track_count = track + 1;

148 }

149 fourxm->tracks[track].adpcm = AV_RL32(buf + 12);

150 fourxm->tracks[track].channels = AV_RL32(buf + 36);

151 fourxm->tracks[track].sample_rate = AV_RL32(buf + 40);

152 fourxm->tracks[track].bits = AV_RL32(buf + 44);

153 fourxm->tracks[track].audio_pts = 0;

154

155 if (fourxm->tracks[track].channels <= 0 ||

156 fourxm->tracks[track].sample_rate <= 0 ||

157 fourxm->tracks[track].bits <= 0) {

158 av_log(s, AV_LOG_ERROR, "audio header invalid\n");

159 return AVERROR_INVALIDDATA;

160 }

161 if (!fourxm->tracks[track].adpcm && fourxm->tracks[track].bits<8) {

162 av_log(s, AV_LOG_ERROR, "bits unspecified for non ADPCM\n");

163 return AVERROR_INVALIDDATA;

164 }

165

166 /* allocate a new AVStream */

167 st = avformat_new_stream(s, NULL);

168 if (!st)

169 return AVERROR(ENOMEM);

170

171 st->id = track;

172 avpriv_set_pts_info(st, 60, 1, fourxm->tracks[track].sample_rate);

173

174 fourxm->tracks[track].stream_index = st->index;

175

176 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

177 st->codec->codec_tag = 0;

178 st->codec->channels = fourxm->tracks[track].channels;

179 st->codec->sample_rate = fourxm->tracks[track].sample_rate;

180 st->codec->bits_per_coded_sample = fourxm->tracks[track].bits;

181 st->codec->bit_rate = st->codec->channels *

182 st->codec->sample_rate *

183 st->codec->bits_per_coded_sample;

184 st->codec->block_align = st->codec->channels *

185 st->codec->bits_per_coded_sample;

186

187 if (fourxm->tracks[track].adpcm){

188 st->codec->codec_id = AV_CODEC_ID_ADPCM_4XM;

189 } else if (st->codec->bits_per_coded_sample == 8) {

190 st->codec->codec_id = AV_CODEC_ID_PCM_U8;

191 } else

192 st->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

193

194 return 0;

195 }

196

197 static int fourxm_read_header(AVFormatContext *s)

198 {

199 AVIOContext *pb = s->pb;

200 unsigned int fourcc_tag;

201 unsigned int size;

202 int header_size;

203 FourxmDemuxContext *fourxm = s->priv_data;

204 unsigned char *header;

205 int i, ret;

206

207 fourxm->track_count = 0;

208 fourxm->tracks = NULL;

209 fourxm->fps = 1.0;

210

211 /* skip the first 3 32-bit numbers */

212 avio_skip(pb, 12);

213

214 /* check for LIST-HEAD */

215 GET_LIST_HEADER();

216 header_size = size - 4;

217 if (fourcc_tag != HEAD_TAG || header_size < 0)

218 return AVERROR_INVALIDDATA;

219

220 /* allocate space for the header and load the whole thing */

221 header = av_malloc(header_size);

222 if (!header)

223 return AVERROR(ENOMEM);

224 if (avio_read(pb, header, header_size) != header_size) {

225 av_free(header);

226 return AVERROR(EIO);

227 }

228

229 /* take the lazy approach and search for any and all vtrk and strk chunks */

230 for (i = 0; i < header_size - 8; i++) {

231 fourcc_tag = AV_RL32(&header[i]);

232 size = AV_RL32(&header[i + 4]);

233 if (size > header_size - i - 8 && (fourcc_tag == vtrk_TAG || fourcc_tag == strk_TAG)) {

234 av_log(s, AV_LOG_ERROR, "chunk larger than array %d>%d\n", size, header_size - i - 8);

235 return AVERROR_INVALIDDATA;

236 }

237

238 if (fourcc_tag == std__TAG) {

239 if (header_size - i < 16) {

240 av_log(s, AV_LOG_ERROR, "std TAG truncated\n");

241 ret = AVERROR_INVALIDDATA;

242 goto fail;

243 }

244 fourxm->fps = av_int2float(AV_RL32(&header[i + 12]));

245 } else if (fourcc_tag == vtrk_TAG) {

246 if ((ret = parse_vtrk(s, fourxm, header + i, size,

247 header_size - i)) < 0)

248 goto fail;

249

250 i += 8 + size;

251 } else if (fourcc_tag == strk_TAG) {

252 if ((ret = parse_strk(s, fourxm, header + i, size,

253 header_size - i)) < 0)

254 goto fail;

255

256 i += 8 + size;

257 }

258 }

259

260 /* skip over the LIST-MOVI chunk (which is where the stream should be */

261 GET_LIST_HEADER();

262 if (fourcc_tag != MOVI_TAG) {

263 ret = AVERROR_INVALIDDATA;

264 goto fail;

265 }

266

267 av_free(header);

268 /* initialize context members */

269 fourxm->video_pts = -1; /* first frame will push to 0 */

270

271 return 0;

272 fail:

273 av_freep(&fourxm->tracks);

274 av_free(header);

275 return ret;

276 }

277

278 static int fourxm_read_packet(AVFormatContext *s,

279 AVPacket *pkt)

280 {

281 FourxmDemuxContext *fourxm = s->priv_data;

282 AVIOContext *pb = s->pb;

283 unsigned int fourcc_tag;

284 unsigned int size;

285 int ret = 0;

286 unsigned int track_number;

287 int packet_read = 0;

288 unsigned char header[8];

289 int audio_frame_count;

290

291 while (!packet_read) {

292 if ((ret = avio_read(s->pb, header, 8)) < 0)

293 return ret;

294 fourcc_tag = AV_RL32(&header[0]);

295 size = AV_RL32(&header[4]);

296 if (avio_feof(pb))

297 return AVERROR(EIO);

298 switch (fourcc_tag) {

299 case LIST_TAG:

300 /* this is a good time to bump the video pts */

301 fourxm->video_pts++;

302

303 /* skip the LIST-* tag and move on to the next fourcc */

304 avio_rl32(pb);

305 break;

306

307 case ifrm_TAG:

308 case pfrm_TAG:

309 case cfrm_TAG:

310 case ifr2_TAG:

311 case pfr2_TAG:

312 case cfr2_TAG:

313 /* allocate 8 more bytes than 'size' to account for fourcc

314 * and size */

315 if (size + 8 < size || av_new_packet(pkt, size + 8))

316 return AVERROR(EIO);

317 pkt->stream_index = fourxm->video_stream_index;

318 pkt->pts = fourxm->video_pts;

319 pkt->pos = avio_tell(s->pb);

320 memcpy(pkt->data, header, 8);

321 ret = avio_read(s->pb, &pkt->data[8], size);

322

323 if (ret < 0) {

324 av_free_packet(pkt);

325 } else {

326 packet_read = 1;

327 av_shrink_packet(pkt, ret + 8);

328 }

329 break;

330

331 case snd__TAG:

332 track_number = avio_rl32(pb);

333 avio_skip(pb, 4);

334 size -= 8;

335

336 if (track_number < fourxm->track_count &&

337 fourxm->tracks[track_number].channels > 0) {

338 ret = av_get_packet(s->pb, pkt, size);

339 if (ret < 0)

340 return AVERROR(EIO);

341 pkt->stream_index =

342 fourxm->tracks[track_number].stream_index;

343 pkt->pts = fourxm->tracks[track_number].audio_pts;

344 packet_read = 1;

345

346 /* pts accounting */

347 audio_frame_count = size;

348 if (fourxm->tracks[track_number].adpcm)

349 audio_frame_count -= 2 * (fourxm->tracks[track_number].channels);

350 audio_frame_count /= fourxm->tracks[track_number].channels;

351 if (fourxm->tracks[track_number].adpcm) {

352 audio_frame_count *= 2;

353 } else

354 audio_frame_count /=

355 (fourxm->tracks[track_number].bits / 8);

356 fourxm->tracks[track_number].audio_pts += audio_frame_count;

357 } else {

358 avio_skip(pb, size);

359 }

360 break;

361

362 default:

363 avio_skip(pb, size);

364 break;

365 }

366 }

367 return ret;

368 }

369

370 static int fourxm_read_close(AVFormatContext *s)

371 {

372 FourxmDemuxContext *fourxm = s->priv_data;

373

374 av_freep(&fourxm->tracks);

375

376 return 0;

377 }

378

379 AVInputFormat ff_fourxm_demuxer = {

380 .name = "4xm",

381 .long_name = NULL_IF_CONFIG_SMALL("4X Technologies"),

382 .priv_data_size = sizeof(FourxmDemuxContext),

383 .read_probe = fourxm_probe,

384 .read_header = fourxm_read_header,

385 .read_packet = fourxm_read_packet,

386 .read_close = fourxm_read_close,

387 };

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