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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 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 /**
23  * @file
24  * id Quake II CIN file demuxer by Mike Melanson (melanson@pcisys.net)
25  * For more information about the id CIN format, visit:
26  * http://www.csse.monash.edu.au/~timf/
27  *
28  * CIN is a somewhat quirky and ill-defined format. Here are some notes
29  * for anyone trying to understand the technical details of this format:
30  *
31  * The format has no definite file signature. This is problematic for a
32  * general-purpose media player that wants to automatically detect file
33  * types. However, a CIN file does start with 5 32-bit numbers that
34  * specify audio and video parameters. This demuxer gets around the lack
35  * of file signature by performing sanity checks on those parameters.
36  * Probabalistically, this is a reasonable solution since the number of
37  * valid combinations of the 5 parameters is a very small subset of the
38  * total 160-bit number space.
39  *
40  * Refer to the function idcin_probe() for the precise A/V parameters
41  * that this demuxer allows.
42  *
43  * Next, each audio and video frame has a duration of 1/14 sec. If the
44  * audio sample rate is a multiple of the common frequency 22050 Hz it will
45  * divide evenly by 14. However, if the sample rate is 11025 Hz:
46  * 11025 (samples/sec) / 14 (frames/sec) = 787.5 (samples/frame)
47  * The way the CIN stores audio in this case is by storing 787 sample
48  * frames in the first audio frame and 788 sample frames in the second
49  * audio frame. Therefore, the total number of bytes in an audio frame
50  * is given as:
51  * audio frame #0: 787 * (bytes/sample) * (# channels) bytes in frame
52  * audio frame #1: 788 * (bytes/sample) * (# channels) bytes in frame
53  * audio frame #2: 787 * (bytes/sample) * (# channels) bytes in frame
54  * audio frame #3: 788 * (bytes/sample) * (# channels) bytes in frame
55  *
56  * Finally, not all id CIN creation tools agree on the resolution of the
57  * color palette, apparently. Some creation tools specify red, green, and
58  * blue palette components in terms of 6-bit VGA color DAC values which
59  * range from 0..63. Other tools specify the RGB components as full 8-bit
60  * values that range from 0..255. Since there are no markers in the file to
61  * differentiate between the two variants, this demuxer uses the following
62  * heuristic:
63  * - load the 768 palette bytes from disk
64  * - assume that they will need to be shifted left by 2 bits to
65  * transform them from 6-bit values to 8-bit values
66  * - scan through all 768 palette bytes
67  * - if any bytes exceed 63, do not shift the bytes at all before
68  * transmitting them to the video decoder
69  */
70 
72 #include "libavutil/imgutils.h"
73 #include "libavutil/intreadwrite.h"
74 #include "avformat.h"
75 #include "internal.h"
76 
77 #define HUFFMAN_TABLE_SIZE (64 * 1024)
78 #define IDCIN_FPS 14
79 
80 typedef struct IdcinDemuxContext {
86 
87  /* demux state variables */
91  int64_t first_pkt_pos;
93 
94 static int idcin_probe(AVProbeData *p)
95 {
96  unsigned int number, sample_rate;
97  unsigned int w, h;
98  int i;
99 
100  /*
101  * This is what you could call a "probabilistic" file check: id CIN
102  * files don't have a definite file signature. In lieu of such a marker,
103  * perform sanity checks on the 5 32-bit header fields:
104  * width, height: greater than 0, less than or equal to 1024
105  * audio sample rate: greater than or equal to 8000, less than or
106  * equal to 48000, or 0 for no audio
107  * audio sample width (bytes/sample): 0 for no audio, or 1 or 2
108  * audio channels: 0 for no audio, or 1 or 2
109  */
110 
111  /* check we have enough data to do all checks, otherwise the
112  0-padding may cause a wrong recognition */
113  if (p->buf_size < 20 + HUFFMAN_TABLE_SIZE + 12)
114  return 0;
115 
116  /* check the video width */
117  w = AV_RL32(&p->buf[0]);
118  if ((w == 0) || (w > 1024))
119  return 0;
120 
121  /* check the video height */
122  h = AV_RL32(&p->buf[4]);
123  if ((h == 0) || (h > 1024))
124  return 0;
125 
126  /* check the audio sample rate */
127  sample_rate = AV_RL32(&p->buf[8]);
128  if (sample_rate && (sample_rate < 8000 || sample_rate > 48000))
129  return 0;
130 
131  /* check the audio bytes/sample */
132  number = AV_RL32(&p->buf[12]);
133  if (number > 2 || sample_rate && !number)
134  return 0;
135 
136  /* check the audio channels */
137  number = AV_RL32(&p->buf[16]);
138  if (number > 2 || sample_rate && !number)
139  return 0;
140 
141  i = 20 + HUFFMAN_TABLE_SIZE;
142  if (AV_RL32(&p->buf[i]) == 1)
143  i += 768;
144 
145  if (i+12 > p->buf_size || AV_RL32(&p->buf[i+8]) != w*h)
146  return 1;
147 
148  /* return half certainty since this check is a bit sketchy */
150 }
151 
153 {
154  AVIOContext *pb = s->pb;
155  IdcinDemuxContext *idcin = s->priv_data;
156  AVStream *st;
157  unsigned int width, height;
158  unsigned int sample_rate, bytes_per_sample, channels;
159  int ret;
160 
161  /* get the 5 header parameters */
162  width = avio_rl32(pb);
163  height = avio_rl32(pb);
164  sample_rate = avio_rl32(pb);
165  bytes_per_sample = avio_rl32(pb);
166  channels = avio_rl32(pb);
167 
168  if (s->pb->eof_reached) {
169  av_log(s, AV_LOG_ERROR, "incomplete header\n");
170  return s->pb->error ? s->pb->error : AVERROR_EOF;
171  }
172 
173  if (av_image_check_size(width, height, 0, s) < 0)
174  return AVERROR_INVALIDDATA;
175  if (sample_rate > 0) {
176  if (sample_rate < 14 || sample_rate > INT_MAX) {
177  av_log(s, AV_LOG_ERROR, "invalid sample rate: %u\n", sample_rate);
178  return AVERROR_INVALIDDATA;
179  }
180  if (bytes_per_sample < 1 || bytes_per_sample > 2) {
181  av_log(s, AV_LOG_ERROR, "invalid bytes per sample: %u\n",
182  bytes_per_sample);
183  return AVERROR_INVALIDDATA;
184  }
185  if (channels < 1 || channels > 2) {
186  av_log(s, AV_LOG_ERROR, "invalid channels: %u\n", channels);
187  return AVERROR_INVALIDDATA;
188  }
189  idcin->audio_present = 1;
190  } else {
191  /* if sample rate is 0, assume no audio */
192  idcin->audio_present = 0;
193  }
194 
195  st = avformat_new_stream(s, NULL);
196  if (!st)
197  return AVERROR(ENOMEM);
198  avpriv_set_pts_info(st, 33, 1, IDCIN_FPS);
199  st->start_time = 0;
200  idcin->video_stream_index = st->index;
203  st->codec->codec_tag = 0; /* no fourcc */
204  st->codec->width = width;
205  st->codec->height = height;
206 
207  /* load up the Huffman tables into extradata */
208  if ((ret = ff_get_extradata(st->codec, pb, HUFFMAN_TABLE_SIZE)) < 0)
209  return ret;
210 
211  if (idcin->audio_present) {
212  idcin->audio_present = 1;
213  st = avformat_new_stream(s, NULL);
214  if (!st)
215  return AVERROR(ENOMEM);
216  avpriv_set_pts_info(st, 63, 1, sample_rate);
217  st->start_time = 0;
218  idcin->audio_stream_index = st->index;
220  st->codec->codec_tag = 1;
221  st->codec->channels = channels;
222  st->codec->channel_layout = channels > 1 ? AV_CH_LAYOUT_STEREO :
225  st->codec->bits_per_coded_sample = bytes_per_sample * 8;
226  st->codec->bit_rate = sample_rate * bytes_per_sample * 8 * channels;
227  st->codec->block_align = idcin->block_align = bytes_per_sample * channels;
228  if (bytes_per_sample == 1)
230  else
232 
233  if (sample_rate % 14 != 0) {
234  idcin->audio_chunk_size1 = (sample_rate / 14) *
235  bytes_per_sample * channels;
236  idcin->audio_chunk_size2 = (sample_rate / 14 + 1) *
237  bytes_per_sample * channels;
238  } else {
239  idcin->audio_chunk_size1 = idcin->audio_chunk_size2 =
240  (sample_rate / 14) * bytes_per_sample * channels;
241  }
242  idcin->current_audio_chunk = 0;
243  }
244 
245  idcin->next_chunk_is_video = 1;
246  idcin->first_pkt_pos = avio_tell(s->pb);
247 
248  return 0;
249 }
250 
252  AVPacket *pkt)
253 {
254  int ret;
255  unsigned int command;
256  unsigned int chunk_size;
257  IdcinDemuxContext *idcin = s->priv_data;
258  AVIOContext *pb = s->pb;
259  int i;
260  int palette_scale;
261  unsigned char r, g, b;
262  unsigned char palette_buffer[768];
263  uint32_t palette[256];
264 
265  if (avio_feof(s->pb))
266  return s->pb->error ? s->pb->error : AVERROR_EOF;
267 
268  if (idcin->next_chunk_is_video) {
269  command = avio_rl32(pb);
270  if (command == 2) {
271  return AVERROR(EIO);
272  } else if (command == 1) {
273  /* trigger a palette change */
274  ret = avio_read(pb, palette_buffer, 768);
275  if (ret < 0) {
276  return ret;
277  } else if (ret != 768) {
278  av_log(s, AV_LOG_ERROR, "incomplete packet\n");
279  return AVERROR(EIO);
280  }
281  /* scale the palette as necessary */
282  palette_scale = 2;
283  for (i = 0; i < 768; i++)
284  if (palette_buffer[i] > 63) {
285  palette_scale = 0;
286  break;
287  }
288 
289  for (i = 0; i < 256; i++) {
290  r = palette_buffer[i * 3 ] << palette_scale;
291  g = palette_buffer[i * 3 + 1] << palette_scale;
292  b = palette_buffer[i * 3 + 2] << palette_scale;
293  palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b);
294  if (palette_scale == 2)
295  palette[i] |= palette[i] >> 6 & 0x30303;
296  }
297  }
298 
299  if (s->pb->eof_reached) {
300  av_log(s, AV_LOG_ERROR, "incomplete packet\n");
301  return s->pb->error ? s->pb->error : AVERROR_EOF;
302  }
303  chunk_size = avio_rl32(pb);
304  if (chunk_size < 4 || chunk_size > INT_MAX - 4) {
305  av_log(s, AV_LOG_ERROR, "invalid chunk size: %u\n", chunk_size);
306  return AVERROR_INVALIDDATA;
307  }
308  /* skip the number of decoded bytes (always equal to width * height) */
309  avio_skip(pb, 4);
310  chunk_size -= 4;
311  ret= av_get_packet(pb, pkt, chunk_size);
312  if (ret < 0)
313  return ret;
314  else if (ret != chunk_size) {
315  av_log(s, AV_LOG_ERROR, "incomplete packet\n");
316  av_free_packet(pkt);
317  return AVERROR(EIO);
318  }
319  if (command == 1) {
320  uint8_t *pal;
321 
324  if (!pal) {
325  av_free_packet(pkt);
326  return AVERROR(ENOMEM);
327  }
328  memcpy(pal, palette, AVPALETTE_SIZE);
329  pkt->flags |= AV_PKT_FLAG_KEY;
330  }
331  pkt->stream_index = idcin->video_stream_index;
332  pkt->duration = 1;
333  } else {
334  /* send out the audio chunk */
335  if (idcin->current_audio_chunk)
336  chunk_size = idcin->audio_chunk_size2;
337  else
338  chunk_size = idcin->audio_chunk_size1;
339  ret= av_get_packet(pb, pkt, chunk_size);
340  if (ret < 0)
341  return ret;
342  pkt->stream_index = idcin->audio_stream_index;
343  pkt->duration = chunk_size / idcin->block_align;
344 
345  idcin->current_audio_chunk ^= 1;
346  }
347 
348  if (idcin->audio_present)
349  idcin->next_chunk_is_video ^= 1;
350 
351  return 0;
352 }
353 
354 static int idcin_read_seek(AVFormatContext *s, int stream_index,
355  int64_t timestamp, int flags)
356 {
357  IdcinDemuxContext *idcin = s->priv_data;
358 
359  if (idcin->first_pkt_pos > 0) {
360  int64_t ret = avio_seek(s->pb, idcin->first_pkt_pos, SEEK_SET);
361  if (ret < 0)
362  return ret;
363  ff_update_cur_dts(s, s->streams[idcin->video_stream_index], 0);
364  idcin->next_chunk_is_video = 1;
365  idcin->current_audio_chunk = 0;
366  return 0;
367  }
368  return -1;
369 }
370 
372  .name = "idcin",
373  .long_name = NULL_IF_CONFIG_SMALL("id Cinematic"),
374  .priv_data_size = sizeof(IdcinDemuxContext),
380 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
Bytestream IO Context.
Definition: avio.h:111
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
void av_free_packet(AVPacket *pkt)
Free a packet.
Definition: avpacket.c:280
static int idcin_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: idcin.c:354
misc image utilities
#define HUFFMAN_TABLE_SIZE
Definition: idcin.c:77
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4075
const char * g
Definition: vf_curves.c:108
int ff_get_extradata(AVCodecContext *avctx, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:2945
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
int index
stream index in AVFormatContext
Definition: avformat.h:843
const char * b
Definition: vf_curves.c:109
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:204
int audio_present
Definition: idcin.c:90
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:277
static AVPacket pkt
#define AV_CH_LAYOUT_STEREO
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs...
Definition: avcodec.h:2298
Format I/O context.
Definition: avformat.h:1273
void ff_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp)
Update cur_dts of all streams based on the given timestamp and AVStream.
Definition: utils.c:1659
uint8_t
#define AVPALETTE_SIZE
Definition: pixfmt.h:33
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:3741
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1341
#define AVERROR_EOF
End of file.
Definition: error.h:55
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:244
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:390
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
Definition: avcodec.h:2995
int duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1440
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:538
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1468
#define U(x)
Definition: vp56_arith.h:37
int current_audio_chunk
Definition: idcin.c:88
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:659
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:175
const char * r
Definition: vf_curves.c:107
int audio_chunk_size2
Definition: idcin.c:84
static int idcin_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: idcin.c:251
int64_t first_pkt_pos
Definition: idcin.c:91
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1428
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2322
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:861
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:451
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
static int idcin_probe(AVProbeData *p)
Definition: idcin.c:94
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:241
int bit_rate
the average bitrate
Definition: avcodec.h:1566
audio channel layout utility functions
int video_stream_index
Definition: idcin.c:81
static int read_probe(AVProbeData *pd)
Definition: jvdec.c:55
int width
picture width / height.
Definition: avcodec.h:1680
int block_align
Definition: idcin.c:85
int audio_stream_index
Definition: idcin.c:82
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:620
Stream structure.
Definition: avformat.h:842
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
sample_rate
enum AVMediaType codec_type
Definition: avcodec.h:1509
#define IDCIN_FPS
Definition: idcin.c:78
enum AVCodecID codec_id
Definition: avcodec.h:1518
int sample_rate
samples per second
Definition: avcodec.h:2261
AVIOContext * pb
I/O context.
Definition: avformat.h:1315
static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Definition: vf_drawtext.c:765
unsigned int codec_tag
fourcc (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
Definition: avcodec.h:1533
BYTE int const BYTE int int int height
Definition: avisynth_c.h:676
int audio_chunk_size1
Definition: idcin.c:83
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
int error
contains the error code or 0 if no error happened
Definition: avio.h:145
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
static int flags
Definition: cpu.c:47
int palette
Definition: v4l.c:61
Main libavformat public API header.
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:894
#define AVFMT_NO_BYTE_SEEK
Format does not allow seeking by bytes.
Definition: avformat.h:480
int eof_reached
true if eof reached
Definition: avio.h:139
int channels
number of audio channels
Definition: avcodec.h:2262
void * priv_data
Format private data.
Definition: avformat.h:1301
static int idcin_read_header(AVFormatContext *s)
Definition: idcin.c:152
int next_chunk_is_video
Definition: idcin.c:89
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:628
AVInputFormat ff_idcin_demuxer
Definition: idcin.c:371
int avio_feof(AVIOContext *s)
feof() equivalent for AVIOContext.
Definition: aviobuf.c:301
uint8_t * av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int size)
Allocate new information of a packet.
Definition: avpacket.c:299
int stream_index
Definition: avcodec.h:1424
#define AV_CH_LAYOUT_MONO
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1399
static int width