FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
rpl.c
Go to the documentation of this file.
1 /*
2  * ARMovie/RPL demuxer
3  * Copyright (c) 2007 Christian Ohm, 2008 Eli Friedman
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  */
21 
22 #include <inttypes.h>
23 #include <stdlib.h>
24 
25 #include "libavutil/avstring.h"
26 #include "libavutil/dict.h"
27 #include "avformat.h"
28 #include "internal.h"
29 
30 #define RPL_SIGNATURE "ARMovie\x0A"
31 #define RPL_SIGNATURE_SIZE 8
32 
33 /** 256 is arbitrary, but should be big enough for any reasonable file. */
34 #define RPL_LINE_LENGTH 256
35 
36 static int rpl_probe(AVProbeData *p)
37 {
38  if (memcmp(p->buf, RPL_SIGNATURE, RPL_SIGNATURE_SIZE))
39  return 0;
40 
41  return AVPROBE_SCORE_MAX;
42 }
43 
44 typedef struct RPLContext {
45  // RPL header data
47 
48  // Stream position data
49  uint32_t chunk_number;
50  uint32_t chunk_part;
51  uint32_t frame_in_part;
52 } RPLContext;
53 
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';
63  return url_feof(pb) ? -1 : 0;
64  }
65  line[i] = b;
66  }
67  line[i] = '\0';
68  return -1;
69 }
70 
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 }
82 
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 }
90 
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 
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);
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:
166  // The header is wrong here, at least sometimes
167  vst->codec->bits_per_coded_sample = 16;
168  break;
169  case 130:
171  break;
172  default:
173  avpriv_report_missing_feature(s, "Video format %i",
174  vst->codec->codec_tag);
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)
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 
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 
354  .name = "rpl",
355  .long_name = NULL_IF_CONFIG_SMALL("RPL / ARMovie"),
356  .priv_data_size = sizeof(RPLContext),
360 };