FFmpeg: libavformat/rpl.c Source File

FFmpeg

[フレーム]

libavformat

rpl.c

Go to the documentation of this file.

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 "libavutil/avstring.h"

23 #include "libavutil/dict.h"

24 #include "avformat.h"

25 #include "internal.h"

26 #include <stdlib.h>

28 #define RPL_SIGNATURE "ARMovie\x0A"

29 #define RPL_SIGNATURE_SIZE 8

31 /** 256 is arbitrary, but should be big enough for any reasonable file. */

32 #define RPL_LINE_LENGTH 256

34 static int rpl_probe(AVProbeData *p)

35 {

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

37 return 0;

39 return AVPROBE_SCORE_MAX;

40 }

42 typedef struct RPLContext {

43 // RPL header data

44 int32_t frames_per_chunk;

46 // Stream position data

47 uint32_t chunk_number;

48 uint32_t chunk_part;

49 uint32_t frame_in_part;

50 } RPLContext;

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

53 {

54 int i;

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

56 int b = avio_r8(pb);

57 if (b == 0)

58 break;

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

60 line[i] = '0円';

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

62 }

63 line[i] = b;

64 }

65 line[i] = '0円';

66 return -1;

67 }

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

70 {

71 unsigned long result = 0;

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

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

74 *error = -1;

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

76 }

77 *endptr = line;

78 return result;

79 }

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

82 {

83 char line[RPL_LINE_LENGTH];

84 const char *endptr;

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

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

87 }

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

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

91 * so this is mostly guessing.

92 */

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

94 {

95 int64_t num, den = 1;

96 AVRational result;

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

98 if (*line == '.')

99 line++;

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

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

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

103 break;

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

105 den *= 10;

106 }

107 if (!num)

108 *error = -1;

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

110 return result;

111 }

112

113 static int rpl_read_header(AVFormatContext *s)

114 {

115 AVIOContext *pb = s->pb;

116 RPLContext *rpl = s->priv_data;

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

118 int total_audio_size;

119 int error = 0;

120

121 uint32_t i;

122

123 int32_t audio_format, chunk_catalog_offset, number_of_chunks;

124 AVRational fps;

125

126 char line[RPL_LINE_LENGTH];

127

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

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

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

131 // number usually isn't important.

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

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

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

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

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

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

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

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

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

141

142 // video headers

143 vst = avformat_new_stream(s, NULL);

144 if (!vst)

145 return AVERROR(ENOMEM);

146 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;

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

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

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

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

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

152 fps = read_fps(line, &error);

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

154

155 // Figure out the video codec

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

157 #if 0

158 case 122:

159 vst->codec->codec_id = AV_CODEC_ID_ESCAPE122;

160 break;

161 #endif

162 case 124:

163 vst->codec->codec_id = AV_CODEC_ID_ESCAPE124;

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

165 vst->codec->bits_per_coded_sample = 16;

166 break;

167 case 130:

168 vst->codec->codec_id = AV_CODEC_ID_ESCAPE130;

169 break;

170 default:

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

172 vst->codec->codec_tag);

173 vst->codec->codec_id = AV_CODEC_ID_NONE;

174 }

175

176 // Audio headers

177

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

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

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

181 if (audio_format) {

182 ast = avformat_new_stream(s, NULL);

183 if (!ast)

184 return AVERROR(ENOMEM);

185 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

186 ast->codec->codec_tag = audio_format;

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

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

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

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

191 // per sample.

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

193 ast->codec->bits_per_coded_sample = 4;

194

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

196 ast->codec->bits_per_coded_sample *

197 ast->codec->channels;

198

199 ast->codec->codec_id = AV_CODEC_ID_NONE;

200 switch (audio_format) {

201 case 1:

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

203 // 16-bit audio is always signed

204 ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

205 break;

206 }

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

208 // samples needed.

209 break;

210 case 101:

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

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

213 // are all unsigned.

214 ast->codec->codec_id = AV_CODEC_ID_PCM_U8;

215 break;

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

217 ast->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_EA_SEAD;

218 break;

219 }

220 break;

221 }

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

223 avpriv_request_sample(s, "Audio format %i", audio_format);

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

225 } else {

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

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

228 }

229

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

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

232 av_log(s, AV_LOG_WARNING,

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

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

235

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

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

238 number_of_chunks++;

239

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

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

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

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

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

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

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

247

248 // Read the index

249 avio_seek(pb, chunk_catalog_offset, SEEK_SET);

250 total_audio_size = 0;

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

252 int64_t offset, video_size, audio_size;

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

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

255 &offset, &video_size, &audio_size))

256 error = -1;

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

258 video_size, rpl->frames_per_chunk, 0);

259 if (ast)

260 av_add_index_entry(ast, offset + video_size, total_audio_size,

261 audio_size, audio_size * 8, 0);

262 total_audio_size += audio_size * 8;

263 }

264

265 if (error) return AVERROR(EIO);

266

267 return 0;

268 }

269

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

271 {

272 RPLContext *rpl = s->priv_data;

273 AVIOContext *pb = s->pb;

274 AVStream* stream;

275 AVIndexEntry* index_entry;

276 uint32_t ret;

277

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

279 rpl->chunk_number++;

280 rpl->chunk_part = 0;

281 }

282

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

284

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

286 return AVERROR_EOF;

287

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

289

290 if (rpl->frame_in_part == 0)

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

292 return AVERROR(EIO);

293

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

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

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

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

298 uint32_t frame_size;

299

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

301 frame_size = avio_rl32(pb);

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

303 return AVERROR(EIO);

304

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

306 if (ret != frame_size) {

307 av_free_packet(pkt);

308 return AVERROR(EIO);

309 }

310 pkt->duration = 1;

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

312 pkt->stream_index = rpl->chunk_part;

313

314 rpl->frame_in_part++;

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

316 rpl->frame_in_part = 0;

317 rpl->chunk_part++;

318 }

319 } else {

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

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

322 av_free_packet(pkt);

323 return AVERROR(EIO);

324 }

325

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

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

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

329 pkt->duration = rpl->frames_per_chunk;

330 } else {

331 // All the audio codecs supported in this container

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

333 pkt->duration = ret * 8;

334 }

335 pkt->pts = index_entry->timestamp;

336 pkt->stream_index = rpl->chunk_part;

337 rpl->chunk_part++;

338 }

339

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

341 // format used doesn't have keyframes.

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

343 pkt->flags |= AV_PKT_FLAG_KEY;

344

345 return ret;

346 }

347

348 AVInputFormat ff_rpl_demuxer = {

349 .name = "rpl",

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

351 .priv_data_size = sizeof(RPLContext),

352 .read_probe = rpl_probe,

353 .read_header = rpl_read_header,

354 .read_packet = rpl_read_packet,

355 };

Generated on Sat Jan 25 2014 19:52:04 for FFmpeg by doxygen 1.8.2