idcin.c
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1 /*
2  * id Quake II CIN File Demuxer
3  * Copyright (c) 2003 The ffmpeg Project
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 
71 #include "libavutil/intreadwrite.h"
72 #include "avformat.h"
73 #include "internal.h"
74 
75 #define HUFFMAN_TABLE_SIZE (64 * 1024)
76 #define IDCIN_FPS 14
77 
78 typedef struct IdcinDemuxContext {
83 
84  /* demux state variables */
88 
89  int64_t pts;
91 
92 static int idcin_probe(AVProbeData *p)
93 {
94  unsigned int number;
95 
96  /*
97  * This is what you could call a "probabilistic" file check: id CIN
98  * files don't have a definite file signature. In lieu of such a marker,
99  * perform sanity checks on the 5 32-bit header fields:
100  * width, height: greater than 0, less than or equal to 1024
101  * audio sample rate: greater than or equal to 8000, less than or
102  * equal to 48000, or 0 for no audio
103  * audio sample width (bytes/sample): 0 for no audio, or 1 or 2
104  * audio channels: 0 for no audio, or 1 or 2
105  */
106 
107  /* check we have enough data to do all checks, otherwise the
108  0-padding may cause a wrong recognition */
109  if (p->buf_size < 20)
110  return 0;
111 
112  /* check the video width */
113  number = AV_RL32(&p->buf[0]);
114  if ((number == 0) || (number > 1024))
115  return 0;
116 
117  /* check the video height */
118  number = AV_RL32(&p->buf[4]);
119  if ((number == 0) || (number > 1024))
120  return 0;
121 
122  /* check the audio sample rate */
123  number = AV_RL32(&p->buf[8]);
124  if ((number != 0) && ((number < 8000) | (number > 48000)))
125  return 0;
126 
127  /* check the audio bytes/sample */
128  number = AV_RL32(&p->buf[12]);
129  if (number > 2)
130  return 0;
131 
132  /* check the audio channels */
133  number = AV_RL32(&p->buf[16]);
134  if (number > 2)
135  return 0;
136 
137  /* return half certainly since this check is a bit sketchy */
138  return AVPROBE_SCORE_MAX / 2;
139 }
140 
142  AVFormatParameters *ap)
143 {
144  AVIOContext *pb = s->pb;
145  IdcinDemuxContext *idcin = s->priv_data;
146  AVStream *st;
147  unsigned int width, height;
148  unsigned int sample_rate, bytes_per_sample, channels;
149 
150  /* get the 5 header parameters */
151  width = avio_rl32(pb);
152  height = avio_rl32(pb);
153  sample_rate = avio_rl32(pb);
154  bytes_per_sample = avio_rl32(pb);
155  channels = avio_rl32(pb);
156 
157  st = avformat_new_stream(s, NULL);
158  if (!st)
159  return AVERROR(ENOMEM);
160  avpriv_set_pts_info(st, 33, 1, IDCIN_FPS);
161  idcin->video_stream_index = st->index;
164  st->codec->codec_tag = 0; /* no fourcc */
165  st->codec->width = width;
166  st->codec->height = height;
167 
168  /* load up the Huffman tables into extradata */
171  if (avio_read(pb, st->codec->extradata, HUFFMAN_TABLE_SIZE) !=
173  return AVERROR(EIO);
174 
175  /* if sample rate is 0, assume no audio */
176  if (sample_rate) {
177  idcin->audio_present = 1;
178  st = avformat_new_stream(s, NULL);
179  if (!st)
180  return AVERROR(ENOMEM);
181  avpriv_set_pts_info(st, 33, 1, IDCIN_FPS);
182  idcin->audio_stream_index = st->index;
184  st->codec->codec_tag = 1;
185  st->codec->channels = channels;
186  st->codec->sample_rate = sample_rate;
187  st->codec->bits_per_coded_sample = bytes_per_sample * 8;
188  st->codec->bit_rate = sample_rate * bytes_per_sample * 8 * channels;
189  st->codec->block_align = bytes_per_sample * channels;
190  if (bytes_per_sample == 1)
192  else
194 
195  if (sample_rate % 14 != 0) {
196  idcin->audio_chunk_size1 = (sample_rate / 14) *
197  bytes_per_sample * channels;
198  idcin->audio_chunk_size2 = (sample_rate / 14 + 1) *
199  bytes_per_sample * channels;
200  } else {
201  idcin->audio_chunk_size1 = idcin->audio_chunk_size2 =
202  (sample_rate / 14) * bytes_per_sample * channels;
203  }
204  idcin->current_audio_chunk = 0;
205  } else
206  idcin->audio_present = 1;
207 
208  idcin->next_chunk_is_video = 1;
209  idcin->pts = 0;
210 
211  return 0;
212 }
213 
215  AVPacket *pkt)
216 {
217  int ret;
218  unsigned int command;
219  unsigned int chunk_size;
220  IdcinDemuxContext *idcin = s->priv_data;
221  AVIOContext *pb = s->pb;
222  int i;
223  int palette_scale;
224  unsigned char r, g, b;
225  unsigned char palette_buffer[768];
226  uint32_t palette[256];
227 
228  if (s->pb->eof_reached)
229  return AVERROR(EIO);
230 
231  if (idcin->next_chunk_is_video) {
232  command = avio_rl32(pb);
233  if (command == 2) {
234  return AVERROR(EIO);
235  } else if (command == 1) {
236  /* trigger a palette change */
237  if (avio_read(pb, palette_buffer, 768) != 768)
238  return AVERROR(EIO);
239  /* scale the palette as necessary */
240  palette_scale = 2;
241  for (i = 0; i < 768; i++)
242  if (palette_buffer[i] > 63) {
243  palette_scale = 0;
244  break;
245  }
246 
247  for (i = 0; i < 256; i++) {
248  r = palette_buffer[i * 3 ] << palette_scale;
249  g = palette_buffer[i * 3 + 1] << palette_scale;
250  b = palette_buffer[i * 3 + 2] << palette_scale;
251  palette[i] = (r << 16) | (g << 8) | (b);
252  }
253  }
254 
255  chunk_size = avio_rl32(pb);
256  /* skip the number of decoded bytes (always equal to width * height) */
257  avio_skip(pb, 4);
258  chunk_size -= 4;
259  ret= av_get_packet(pb, pkt, chunk_size);
260  if (ret < 0)
261  return ret;
262  if (command == 1) {
263  uint8_t *pal;
264 
267  if (ret < 0)
268  return ret;
269  memcpy(pal, palette, AVPALETTE_SIZE);
270  }
271  pkt->stream_index = idcin->video_stream_index;
272  pkt->pts = idcin->pts;
273  } else {
274  /* send out the audio chunk */
275  if (idcin->current_audio_chunk)
276  chunk_size = idcin->audio_chunk_size2;
277  else
278  chunk_size = idcin->audio_chunk_size1;
279  ret= av_get_packet(pb, pkt, chunk_size);
280  if (ret < 0)
281  return ret;
282  pkt->stream_index = idcin->audio_stream_index;
283  pkt->pts = idcin->pts;
284 
285  idcin->current_audio_chunk ^= 1;
286  idcin->pts++;
287  }
288 
289  if (idcin->audio_present)
290  idcin->next_chunk_is_video ^= 1;
291 
292  return ret;
293 }
294 
296  .name = "idcin",
297  .long_name = NULL_IF_CONFIG_SMALL("id Cinematic format"),
298  .priv_data_size = sizeof(IdcinDemuxContext),
302 };