rpl.c
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1 /*
2  * ARMovie/RPL demuxer
3  * Copyright (c) 2007 Christian Ohm, 2008 Eli Friedman
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/avstring.h"
23 #include "libavutil/dict.h"
24 #include "avformat.h"
25 #include "internal.h"
26 #include <stdlib.h>
27 
28 #define RPL_SIGNATURE "ARMovie\x0A"
29 #define RPL_SIGNATURE_SIZE 8
30 
32 #define RPL_LINE_LENGTH 256
33 
34 static int rpl_probe(AVProbeData *p)
35 {
36  if (memcmp(p->buf, RPL_SIGNATURE, RPL_SIGNATURE_SIZE))
37  return 0;
38 
39  return AVPROBE_SCORE_MAX;
40 }
41 
42 typedef struct RPLContext {
43  // RPL header data
45 
46  // Stream position data
47  uint32_t chunk_number;
48  uint32_t chunk_part;
49  uint32_t frame_in_part;
50 } RPLContext;
51 
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';
61  return 0;
62  }
63  line[i] = b;
64  }
65  line[i] = '\0';
66  return -1;
67 }
68 
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 }
80 
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 }
88 
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 
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);
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 = CODEC_ID_ESCAPE122;
160  break;
161 #endif
162  case 124:
164  // The header is wrong here, at least sometimes
165  vst->codec->bits_per_coded_sample = 16;
166  break;
167 #if 0
168  case 130:
169  vst->codec->codec_id = CODEC_ID_ESCAPE130;
170  break;
171 #endif
172  default:
174  "RPL video format %i not supported yet!\n",
175  vst->codec->codec_tag);
176  vst->codec->codec_id = CODEC_ID_NONE;
177  }
178 
179  // Audio headers
180 
181  // ARMovie supports multiple audio tracks; I don't have any
182  // samples, though. This code will ignore additional tracks.
183  audio_format = read_line_and_int(pb, &error); // audio format ID
184  if (audio_format) {
185  ast = avformat_new_stream(s, NULL);
186  if (!ast)
187  return AVERROR(ENOMEM);
188  ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
189  ast->codec->codec_tag = audio_format;
190  ast->codec->sample_rate = read_line_and_int(pb, &error); // audio bitrate
191  ast->codec->channels = read_line_and_int(pb, &error); // number of audio channels
192  ast->codec->bits_per_coded_sample = read_line_and_int(pb, &error); // audio bits per sample
193  // At least one sample uses 0 for ADPCM, which is really 4 bits
194  // per sample.
195  if (ast->codec->bits_per_coded_sample == 0)
196  ast->codec->bits_per_coded_sample = 4;
197 
198  ast->codec->bit_rate = ast->codec->sample_rate *
199  ast->codec->bits_per_coded_sample *
200  ast->codec->channels;
201 
202  ast->codec->codec_id = CODEC_ID_NONE;
203  switch (audio_format) {
204  case 1:
205  if (ast->codec->bits_per_coded_sample == 16) {
206  // 16-bit audio is always signed
207  ast->codec->codec_id = CODEC_ID_PCM_S16LE;
208  break;
209  }
210  // There are some other formats listed as legal per the spec;
211  // samples needed.
212  break;
213  case 101:
214  if (ast->codec->bits_per_coded_sample == 8) {
215  // The samples with this kind of audio that I have
216  // are all unsigned.
217  ast->codec->codec_id = CODEC_ID_PCM_U8;
218  break;
219  } else if (ast->codec->bits_per_coded_sample == 4) {
220  ast->codec->codec_id = CODEC_ID_ADPCM_IMA_EA_SEAD;
221  break;
222  }
223  break;
224  }
225  if (ast->codec->codec_id == CODEC_ID_NONE) {
227  "RPL audio format %i not supported yet!\n",
228  audio_format);
229  }
230  avpriv_set_pts_info(ast, 32, 1, ast->codec->bit_rate);
231  } else {
232  for (i = 0; i < 3; i++)
233  error |= read_line(pb, line, sizeof(line));
234  }
235 
236  rpl->frames_per_chunk = read_line_and_int(pb, &error); // video frames per chunk
237  if (rpl->frames_per_chunk > 1 && vst->codec->codec_tag != 124)
239  "Don't know how to split frames for video format %i. "
240  "Video stream will be broken!\n", vst->codec->codec_tag);
241 
242  number_of_chunks = read_line_and_int(pb, &error); // number of chunks in the file
243  // The number in the header is actually the index of the last chunk.
244  number_of_chunks++;
245 
246  error |= read_line(pb, line, sizeof(line)); // "even" chunk size in bytes
247  error |= read_line(pb, line, sizeof(line)); // "odd" chunk size in bytes
248  chunk_catalog_offset = // offset of the "chunk catalog"
249  read_line_and_int(pb, &error); // (file index)
250  error |= read_line(pb, line, sizeof(line)); // offset to "helpful" sprite
251  error |= read_line(pb, line, sizeof(line)); // size of "helpful" sprite
252  error |= read_line(pb, line, sizeof(line)); // offset to key frame list
253 
254  // Read the index
255  avio_seek(pb, chunk_catalog_offset, SEEK_SET);
256  total_audio_size = 0;
257  for (i = 0; i < number_of_chunks; i++) {
258  int64_t offset, video_size, audio_size;
259  error |= read_line(pb, line, sizeof(line));
260  if (3 != sscanf(line, "%"PRId64" , %"PRId64" ; %"PRId64,
261  &offset, &video_size, &audio_size))
262  error = -1;
263  av_add_index_entry(vst, offset, i * rpl->frames_per_chunk,
264  video_size, rpl->frames_per_chunk, 0);
265  if (ast)
266  av_add_index_entry(ast, offset + video_size, total_audio_size,
267  audio_size, audio_size * 8, 0);
268  total_audio_size += audio_size * 8;
269  }
270 
271  if (error) return AVERROR(EIO);
272 
273  return 0;
274 }
275 
277 {
278  RPLContext *rpl = s->priv_data;
279  AVIOContext *pb = s->pb;
280  AVStream* stream;
281  AVIndexEntry* index_entry;
282  uint32_t ret;
283 
284  if (rpl->chunk_part == s->nb_streams) {
285  rpl->chunk_number++;
286  rpl->chunk_part = 0;
287  }
288 
289  stream = s->streams[rpl->chunk_part];
290 
291  if (rpl->chunk_number >= stream->nb_index_entries)
292  return -1;
293 
294  index_entry = &stream->index_entries[rpl->chunk_number];
295 
296  if (rpl->frame_in_part == 0)
297  if (avio_seek(pb, index_entry->pos, SEEK_SET) < 0)
298  return AVERROR(EIO);
299 
300  if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
301  stream->codec->codec_tag == 124) {
302  // We have to split Escape 124 frames because there are
303  // multiple frames per chunk in Escape 124 samples.
304  uint32_t frame_size;
305 
306  avio_skip(pb, 4); /* flags */
307  frame_size = avio_rl32(pb);
308  if (avio_seek(pb, -8, SEEK_CUR) < 0)
309  return AVERROR(EIO);
310 
311  ret = av_get_packet(pb, pkt, frame_size);
312  if (ret != frame_size) {
313  av_free_packet(pkt);
314  return AVERROR(EIO);
315  }
316  pkt->duration = 1;
317  pkt->pts = index_entry->timestamp + rpl->frame_in_part;
318  pkt->stream_index = rpl->chunk_part;
319 
320  rpl->frame_in_part++;
321  if (rpl->frame_in_part == rpl->frames_per_chunk) {
322  rpl->frame_in_part = 0;
323  rpl->chunk_part++;
324  }
325  } else {
326  ret = av_get_packet(pb, pkt, index_entry->size);
327  if (ret != index_entry->size) {
328  av_free_packet(pkt);
329  return AVERROR(EIO);
330  }
331 
332  if (stream->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
333  // frames_per_chunk should always be one here; the header
334  // parsing will warn if it isn't.
335  pkt->duration = rpl->frames_per_chunk;
336  } else {
337  // All the audio codecs supported in this container
338  // (at least so far) are constant-bitrate.
339  pkt->duration = ret * 8;
340  }
341  pkt->pts = index_entry->timestamp;
342  pkt->stream_index = rpl->chunk_part;
343  rpl->chunk_part++;
344  }
345 
346  // None of the Escape formats have keyframes, and the ADPCM
347  // format used doesn't have keyframes.
348  if (rpl->chunk_number == 0 && rpl->frame_in_part == 0)
349  pkt->flags |= AV_PKT_FLAG_KEY;
350 
351  return ret;
352 }
353 
355  .name = "rpl",
356  .long_name = NULL_IF_CONFIG_SMALL("RPL/ARMovie format"),
357  .priv_data_size = sizeof(RPLContext),
361 };