FFmpeg
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  * Probabilistically, 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(const 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  }
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->codecpar->codec_tag = 0; /* no fourcc */
204  st->codecpar->width = width;
205  st->codecpar->height = height;
206 
207  /* load up the Huffman tables into extradata */
208  if ((ret = ff_get_extradata(s, st->codecpar, 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->codecpar->codec_tag = 1;
221  st->codecpar->channels = channels;
222  st->codecpar->channel_layout = channels > 1 ? AV_CH_LAYOUT_STEREO :
225  st->codecpar->bits_per_coded_sample = bytes_per_sample * 8;
226  st->codecpar->bit_rate = sample_rate * bytes_per_sample * 8 * channels;
227  st->codecpar->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_packet_unref(pkt);
317  return AVERROR(EIO);
318  }
319  if (command == 1) {
320  uint8_t *pal;
321 
324  if (!pal) {
325  av_packet_unref(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
Bytestream IO Context.
Definition: avio.h:161
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
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:4929
const char * g
Definition: vf_curves.c:115
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
channels
Definition: aptx.c:30
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int index
stream index in AVFormatContext
Definition: avformat.h:882
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
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:334
static AVPacket pkt
#define AV_CH_LAYOUT_STEREO
Format I/O context.
Definition: avformat.h:1358
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:1963
uint8_t
int width
Video only.
Definition: avcodec.h:4034
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1498
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
#define height
#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:310
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
uint64_t channel_layout
Audio only.
Definition: avcodec.h:4070
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:650
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3997
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1512
#define U(x)
Definition: vp56_arith.h:37
int current_audio_chunk
Definition: idcin.c:88
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
An AV_PKT_DATA_PALETTE side data packet contains exactly AVPALETTE_SIZE bytes worth of palette...
Definition: avcodec.h:1193
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * r
Definition: vf_curves.c:114
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
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:1486
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
int block_align
Audio only.
Definition: avcodec.h:4085
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:282
#define b
Definition: input.c:41
audio channel layout utility functions
int video_stream_index
Definition: idcin.c:81
#define width
int block_align
Definition: idcin.c:85
uint8_t w
Definition: llviddspenc.c:38
#define s(width, name)
Definition: cbs_vp9.c:257
int audio_stream_index
Definition: idcin.c:82
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
sample_rate
#define IDCIN_FPS
Definition: idcin.c:78
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
static int command(AVFilterContext *ctx, const char *cmd, const char *arg, char *res, int res_len, int flags)
Definition: vf_drawtext.c:869
int audio_chunk_size1
Definition: idcin.c:83
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:456
int error
contains the error code or 0 if no error happened
Definition: avio.h:245
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
#define flags(name, subs,...)
Definition: cbs_av1.c:561
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int sample_rate
Audio only.
Definition: avcodec.h:4078
Main libavformat public API header.
static int idcin_probe(const AVProbeData *p)
Definition: idcin.c:94
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:920
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, 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:3339
#define AVFMT_NO_BYTE_SEEK
Format does not allow seeking by bytes.
Definition: avformat.h:475
int eof_reached
true if was unable to read due to error or eof
Definition: avio.h:239
void * priv_data
Format private data.
Definition: avformat.h:1386
static int idcin_read_header(AVFormatContext *s)
Definition: idcin.c:152
int next_chunk_is_video
Definition: idcin.c:89
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:4010
int channels
Audio only.
Definition: avcodec.h:4074
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVInputFormat ff_idcin_demuxer
Definition: idcin.c:371
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:361
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: avcodec.h:3972
uint8_t * av_packet_new_side_data(AVPacket *pkt, enum AVPacketSideDataType type, int size)
Allocate new information of a packet.
Definition: avpacket.c:329
int stream_index
Definition: avcodec.h:1482
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
#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:1457