FFmpeg: libavformat/rpl.c Source File

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libavformat

rpl.c

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1 /*

2 * ARMovie/RPL demuxer

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 #include <inttypes.h>

23 #include <stdlib.h>

25 #include "libavutil/avstring.h"

26 #include "libavutil/dict.h"

27 #include "avformat.h"

28 #include "internal.h"

30 #define RPL_SIGNATURE "ARMovie\x0A"

31 #define RPL_SIGNATURE_SIZE 8

33 /** 256 is arbitrary, but should be big enough for any reasonable file. */

34 #define RPL_LINE_LENGTH 256

36 static int rpl_probe(AVProbeData *p)

37 {

38 if (memcmp(p->buf, RPL_SIGNATURE, RPL_SIGNATURE_SIZE))

39 return 0;

41 return AVPROBE_SCORE_MAX;

42 }

44 typedef struct RPLContext {

45 // RPL header data

46 int32_t frames_per_chunk;

48 // Stream position data

49 uint32_t chunk_number;

50 uint32_t chunk_part;

51 uint32_t frame_in_part;

52 } RPLContext;

54 static int read_line(AVIOContext * pb, char* line, int bufsize)

55 {

56 int i;

57 for (i = 0; i < bufsize - 1; i++) {

58 int b = avio_r8(pb);

59 if (b == 0)

60 break;

61 if (b == '\n') {

62 line[i] = '0円';

63 return url_feof(pb) ? -1 : 0;

64 }

65 line[i] = b;

66 }

67 line[i] = '0円';

68 return -1;

69 }

71 static int32_t read_int(const char* line, const char** endptr, int* error)

72 {

73 unsigned long result = 0;

74 for (; *line>='0' && *line<='9'; line++) {

75 if (result > (0x7FFFFFFF - 9) / 10)

76 *error = -1;

77 result = 10 * result + *line - '0';

78 }

79 *endptr = line;

80 return result;

81 }

83 static int32_t read_line_and_int(AVIOContext * pb, int* error)

84 {

85 char line[RPL_LINE_LENGTH];

86 const char *endptr;

87 *error |= read_line(pb, line, sizeof(line));

88 return read_int(line, &endptr, error);

89 }

91 /** Parsing for fps, which can be a fraction. Unfortunately,

92 * the spec for the header leaves out a lot of details,

93 * so this is mostly guessing.

94 */

95 static AVRational read_fps(const char* line, int* error)

96 {

97 int64_t num, den = 1;

98 AVRational result;

99 num = read_int(line, &line, error);

100 if (*line == '.')

101 line++;

102 for (; *line>='0' && *line<='9'; line++) {

103 // Truncate any numerator too large to fit into an int64_t

104 if (num > (INT64_MAX - 9) / 10 || den > INT64_MAX / 10)

105 break;

106 num = 10 * num + *line - '0';

107 den *= 10;

108 }

109 if (!num)

110 *error = -1;

111 av_reduce(&result.num, &result.den, num, den, 0x7FFFFFFF);

112 return result;

113 }

114

115 static int rpl_read_header(AVFormatContext *s)

116 {

117 AVIOContext *pb = s->pb;

118 RPLContext *rpl = s->priv_data;

119 AVStream *vst = NULL, *ast = NULL;

120 int total_audio_size;

121 int error = 0;

122

123 uint32_t i;

124

125 int32_t audio_format, chunk_catalog_offset, number_of_chunks;

126 AVRational fps;

127

128 char line[RPL_LINE_LENGTH];

129

130 // The header for RPL/ARMovie files is 21 lines of text

131 // containing the various header fields. The fields are always

132 // in the same order, and other text besides the first

133 // number usually isn't important.

134 // (The spec says that there exists some significance

135 // for the text in a few cases; samples needed.)

136 error |= read_line(pb, line, sizeof(line)); // ARMovie

137 error |= read_line(pb, line, sizeof(line)); // movie name

138 av_dict_set(&s->metadata, "title" , line, 0);

139 error |= read_line(pb, line, sizeof(line)); // date/copyright

140 av_dict_set(&s->metadata, "copyright", line, 0);

141 error |= read_line(pb, line, sizeof(line)); // author and other

142 av_dict_set(&s->metadata, "author" , line, 0);

143

144 // video headers

145 vst = avformat_new_stream(s, NULL);

146 if (!vst)

147 return AVERROR(ENOMEM);

148 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

149 vst->codec->codec_tag = read_line_and_int(pb, &error); // video format

150 vst->codec->width = read_line_and_int(pb, &error); // video width

151 vst->codec->height = read_line_and_int(pb, &error); // video height

152 vst->codec->bits_per_coded_sample = read_line_and_int(pb, &error); // video bits per sample

153 error |= read_line(pb, line, sizeof(line)); // video frames per second

154 fps = read_fps(line, &error);

155 avpriv_set_pts_info(vst, 32, fps.den, fps.num);

156

157 // Figure out the video codec

158 switch (vst->codec->codec_tag) {

159 #if 0

160 case 122:

161 vst->codec->codec_id = AV_CODEC_ID_ESCAPE122;

162 break;

163 #endif

164 case 124:

165 vst->codec->codec_id = AV_CODEC_ID_ESCAPE124;

166 // The header is wrong here, at least sometimes

167 vst->codec->bits_per_coded_sample = 16;

168 break;

169 case 130:

170 vst->codec->codec_id = AV_CODEC_ID_ESCAPE130;

171 break;

172 default:

173 avpriv_report_missing_feature(s, "Video format %i",

174 vst->codec->codec_tag);

175 vst->codec->codec_id = AV_CODEC_ID_NONE;

176 }

177

178 // Audio headers

179

180 // ARMovie supports multiple audio tracks; I don't have any

181 // samples, though. This code will ignore additional tracks.

182 audio_format = read_line_and_int(pb, &error); // audio format ID

183 if (audio_format) {

184 ast = avformat_new_stream(s, NULL);

185 if (!ast)

186 return AVERROR(ENOMEM);

187 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

188 ast->codec->codec_tag = audio_format;

189 ast->codec->sample_rate = read_line_and_int(pb, &error); // audio bitrate

190 ast->codec->channels = read_line_and_int(pb, &error); // number of audio channels

191 ast->codec->bits_per_coded_sample = read_line_and_int(pb, &error); // audio bits per sample

192 // At least one sample uses 0 for ADPCM, which is really 4 bits

193 // per sample.

194 if (ast->codec->bits_per_coded_sample == 0)

195 ast->codec->bits_per_coded_sample = 4;

196

197 ast->codec->bit_rate = ast->codec->sample_rate *

198 ast->codec->bits_per_coded_sample *

199 ast->codec->channels;

200

201 ast->codec->codec_id = AV_CODEC_ID_NONE;

202 switch (audio_format) {

203 case 1:

204 if (ast->codec->bits_per_coded_sample == 16) {

205 // 16-bit audio is always signed

206 ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

207 break;

208 }

209 // There are some other formats listed as legal per the spec;

210 // samples needed.

211 break;

212 case 101:

213 if (ast->codec->bits_per_coded_sample == 8) {

214 // The samples with this kind of audio that I have

215 // are all unsigned.

216 ast->codec->codec_id = AV_CODEC_ID_PCM_U8;

217 break;

218 } else if (ast->codec->bits_per_coded_sample == 4) {

219 ast->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_EA_SEAD;

220 break;

221 }

222 break;

223 }

224 if (ast->codec->codec_id == AV_CODEC_ID_NONE)

225 avpriv_request_sample(s, "Audio format %"PRId32,

226 audio_format);

227 avpriv_set_pts_info(ast, 32, 1, ast->codec->bit_rate);

228 } else {

229 for (i = 0; i < 3; i++)

230 error |= read_line(pb, line, sizeof(line));

231 }

232

233 rpl->frames_per_chunk = read_line_and_int(pb, &error); // video frames per chunk

234 if (rpl->frames_per_chunk > 1 && vst->codec->codec_tag != 124)

235 av_log(s, AV_LOG_WARNING,

236 "Don't know how to split frames for video format %i. "

237 "Video stream will be broken!\n", vst->codec->codec_tag);

238

239 number_of_chunks = read_line_and_int(pb, &error); // number of chunks in the file

240 // The number in the header is actually the index of the last chunk.

241 number_of_chunks++;

242

243 error |= read_line(pb, line, sizeof(line)); // "even" chunk size in bytes

244 error |= read_line(pb, line, sizeof(line)); // "odd" chunk size in bytes

245 chunk_catalog_offset = // offset of the "chunk catalog"

246 read_line_and_int(pb, &error); // (file index)

247 error |= read_line(pb, line, sizeof(line)); // offset to "helpful" sprite

248 error |= read_line(pb, line, sizeof(line)); // size of "helpful" sprite

249 error |= read_line(pb, line, sizeof(line)); // offset to key frame list

250

251 // Read the index

252 avio_seek(pb, chunk_catalog_offset, SEEK_SET);

253 total_audio_size = 0;

254 for (i = 0; !error && i < number_of_chunks; i++) {

255 int64_t offset, video_size, audio_size;

256 error |= read_line(pb, line, sizeof(line));

257 if (3 != sscanf(line, "%"SCNd64" , %"SCNd64" ; %"SCNd64,

258 &offset, &video_size, &audio_size)) {

259 error = -1;

260 continue;

261 }

262 av_add_index_entry(vst, offset, i * rpl->frames_per_chunk,

263 video_size, rpl->frames_per_chunk, 0);

264 if (ast)

265 av_add_index_entry(ast, offset + video_size, total_audio_size,

266 audio_size, audio_size * 8, 0);

267 total_audio_size += audio_size * 8;

268 }

269

270 if (error) return AVERROR(EIO);

271

272 return 0;

273 }

274

275 static int rpl_read_packet(AVFormatContext *s, AVPacket *pkt)

276 {

277 RPLContext *rpl = s->priv_data;

278 AVIOContext *pb = s->pb;

279 AVStream* stream;

280 AVIndexEntry* index_entry;

281 uint32_t ret;

282

283 if (rpl->chunk_part == s->nb_streams) {

284 rpl->chunk_number++;

285 rpl->chunk_part = 0;

286 }

287

288 stream = s->streams[rpl->chunk_part];

289

290 if (rpl->chunk_number >= stream->nb_index_entries)

291 return AVERROR_EOF;

292

293 index_entry = &stream->index_entries[rpl->chunk_number];

294

295 if (rpl->frame_in_part == 0)

296 if (avio_seek(pb, index_entry->pos, SEEK_SET) < 0)

297 return AVERROR(EIO);

298

299 if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO &&

300 stream->codec->codec_tag == 124) {

301 // We have to split Escape 124 frames because there are

302 // multiple frames per chunk in Escape 124 samples.

303 uint32_t frame_size;

304

305 avio_skip(pb, 4); /* flags */

306 frame_size = avio_rl32(pb);

307 if (avio_seek(pb, -8, SEEK_CUR) < 0)

308 return AVERROR(EIO);

309

310 ret = av_get_packet(pb, pkt, frame_size);

311 if (ret != frame_size) {

312 av_free_packet(pkt);

313 return AVERROR(EIO);

314 }

315 pkt->duration = 1;

316 pkt->pts = index_entry->timestamp + rpl->frame_in_part;

317 pkt->stream_index = rpl->chunk_part;

318

319 rpl->frame_in_part++;

320 if (rpl->frame_in_part == rpl->frames_per_chunk) {

321 rpl->frame_in_part = 0;

322 rpl->chunk_part++;

323 }

324 } else {

325 ret = av_get_packet(pb, pkt, index_entry->size);

326 if (ret != index_entry->size) {

327 av_free_packet(pkt);

328 return AVERROR(EIO);

329 }

330

331 if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

332 // frames_per_chunk should always be one here; the header

333 // parsing will warn if it isn't.

334 pkt->duration = rpl->frames_per_chunk;

335 } else {

336 // All the audio codecs supported in this container

337 // (at least so far) are constant-bitrate.

338 pkt->duration = ret * 8;

339 }

340 pkt->pts = index_entry->timestamp;

341 pkt->stream_index = rpl->chunk_part;

342 rpl->chunk_part++;

343 }

344

345 // None of the Escape formats have keyframes, and the ADPCM

346 // format used doesn't have keyframes.

347 if (rpl->chunk_number == 0 && rpl->frame_in_part == 0)

348 pkt->flags |= AV_PKT_FLAG_KEY;

349

350 return ret;

351 }

352

353 AVInputFormat ff_rpl_demuxer = {

354 .name = "rpl",

355 .long_name = NULL_IF_CONFIG_SMALL("RPL / ARMovie"),

356 .priv_data_size = sizeof(RPLContext),

357 .read_probe = rpl_probe,

358 .read_header = rpl_read_header,

359 .read_packet = rpl_read_packet,

360 };

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