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 "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 av_log(s, AV_LOG_WARNING,

172 "RPL video format %i not supported yet!\n",

173 vst->codec->codec_tag);

174 vst->codec->codec_id = AV_CODEC_ID_NONE;

175 }

176

177 // Audio headers

178

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

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

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

182 if (audio_format) {

183 ast = avformat_new_stream(s, NULL);

184 if (!ast)

185 return AVERROR(ENOMEM);

186 ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;

187 ast->codec->codec_tag = audio_format;

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

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

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

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

192 // per sample.

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

194 ast->codec->bits_per_coded_sample = 4;

195

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

197 ast->codec->bits_per_coded_sample *

198 ast->codec->channels;

199

200 ast->codec->codec_id = AV_CODEC_ID_NONE;

201 switch (audio_format) {

202 case 1:

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

204 // 16-bit audio is always signed

205 ast->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

206 break;

207 }

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

209 // samples needed.

210 break;

211 case 101:

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

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

214 // are all unsigned.

215 ast->codec->codec_id = AV_CODEC_ID_PCM_U8;

216 break;

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

218 ast->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_EA_SEAD;

219 break;

220 }

221 break;

222 }

223 if (ast->codec->codec_id == AV_CODEC_ID_NONE) {

224 av_log(s, AV_LOG_WARNING,

225 "RPL audio format %i not supported yet!\n",

226 audio_format);

227 }

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

229 } else {

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

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

232 }

233

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

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

236 av_log(s, AV_LOG_WARNING,

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

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

239

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

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

242 number_of_chunks++;

243

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

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

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

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

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

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

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

251

252 // Read the index

253 avio_seek(pb, chunk_catalog_offset, SEEK_SET);

254 total_audio_size = 0;

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

256 int64_t offset, video_size, audio_size;

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

258 if (3 != sscanf(line, "%"PRId64" , %"PRId64" ; %"PRId64,

259 &offset, &video_size, &audio_size))

260 error = -1;

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

262 video_size, rpl->frames_per_chunk, 0);

263 if (ast)

264 av_add_index_entry(ast, offset + video_size, total_audio_size,

265 audio_size, audio_size * 8, 0);

266 total_audio_size += audio_size * 8;

267 }

268

269 if (error) return AVERROR(EIO);

270

271 return 0;

272 }

273

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

275 {

276 RPLContext *rpl = s->priv_data;

277 AVIOContext *pb = s->pb;

278 AVStream* stream;

279 AVIndexEntry* index_entry;

280 uint32_t ret;

281

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

283 rpl->chunk_number++;

284 rpl->chunk_part = 0;

285 }

286

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

288

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

290 return AVERROR_EOF;

291

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

293

294 if (rpl->frame_in_part == 0)

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

296 return AVERROR(EIO);

297

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

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

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

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

302 uint32_t frame_size;

303

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

305 frame_size = avio_rl32(pb);

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

307 return AVERROR(EIO);

308

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

310 if (ret != frame_size) {

311 av_free_packet(pkt);

312 return AVERROR(EIO);

313 }

314 pkt->duration = 1;

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

316 pkt->stream_index = rpl->chunk_part;

317

318 rpl->frame_in_part++;

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

320 rpl->frame_in_part = 0;

321 rpl->chunk_part++;

322 }

323 } else {

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

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

326 av_free_packet(pkt);

327 return AVERROR(EIO);

328 }

329

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

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

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

333 pkt->duration = rpl->frames_per_chunk;

334 } else {

335 // All the audio codecs supported in this container

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

337 pkt->duration = ret * 8;

338 }

339 pkt->pts = index_entry->timestamp;

340 pkt->stream_index = rpl->chunk_part;

341 rpl->chunk_part++;

342 }

343

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

345 // format used doesn't have keyframes.

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

347 pkt->flags |= AV_PKT_FLAG_KEY;

348

349 return ret;

350 }

351

352 AVInputFormat ff_rpl_demuxer = {

353 .name = "rpl",

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

355 .priv_data_size = sizeof(RPLContext),

356 .read_probe = rpl_probe,

357 .read_header = rpl_read_header,

358 .read_packet = rpl_read_packet,

359 };

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