FFmpeg
rl2.c
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1 /*
2  * RL2 Format Demuxer
3  * Copyright (c) 2008 Sascha Sommer (saschasommer@freenet.de)
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  * RL2 file demuxer
24  * @file
25  * @author Sascha Sommer (saschasommer@freenet.de)
26  * @see http://wiki.multimedia.cx/index.php?title=RL2
27  *
28  * extradata:
29  * 2 byte le initial drawing offset within 320x200 viewport
30  * 4 byte le number of used colors
31  * 256 * 3 bytes rgb palette
32  * optional background_frame
33  */
34 
35 #include <stdint.h>
36 
37 #include "libavutil/intreadwrite.h"
38 #include "libavutil/mathematics.h"
39 #include "avformat.h"
40 #include "internal.h"
41 
42 #define EXTRADATA1_SIZE (6 + 256 * 3) ///< video base, clr, palette
43 
44 #define FORM_TAG MKBETAG('F', 'O', 'R', 'M')
45 #define RLV2_TAG MKBETAG('R', 'L', 'V', '2')
46 #define RLV3_TAG MKBETAG('R', 'L', 'V', '3')
47 
48 typedef struct Rl2DemuxContext {
49  unsigned int index_pos[2]; ///< indexes in the sample tables
51 
52 
53 /**
54  * check if the file is in rl2 format
55  * @param p probe buffer
56  * @return 0 when the probe buffer does not contain rl2 data, > 0 otherwise
57  */
58 static int rl2_probe(const AVProbeData *p)
59 {
60 
61  if(AV_RB32(&p->buf[0]) != FORM_TAG)
62  return 0;
63 
64  if(AV_RB32(&p->buf[8]) != RLV2_TAG &&
65  AV_RB32(&p->buf[8]) != RLV3_TAG)
66  return 0;
67 
68  return AVPROBE_SCORE_MAX;
69 }
70 
71 /**
72  * read rl2 header data and setup the avstreams
73  * @param s demuxer context
74  * @return 0 on success, AVERROR otherwise
75  */
77 {
78  AVIOContext *pb = s->pb;
79  AVStream *st;
80  unsigned int frame_count;
81  unsigned int audio_frame_counter = 0;
82  unsigned int video_frame_counter = 0;
83  unsigned int back_size;
84  unsigned short sound_rate;
85  unsigned short rate;
86  unsigned short channels;
87  unsigned short def_sound_size;
88  unsigned int signature;
89  unsigned int pts_den = 11025; /* video only case */
90  unsigned int pts_num = 1103;
91  unsigned int* chunk_offset = NULL;
92  int* chunk_size = NULL;
93  int* audio_size = NULL;
94  int i;
95  int ret = 0;
96 
97  avio_skip(pb,4); /* skip FORM tag */
98  back_size = avio_rl32(pb); /**< get size of the background frame */
99  signature = avio_rb32(pb);
100  avio_skip(pb, 4); /* data size */
101  frame_count = avio_rl32(pb);
102 
103  /* disallow back_sizes and frame_counts that may lead to overflows later */
104  if(back_size > INT_MAX/2 || frame_count > INT_MAX / sizeof(uint32_t))
105  return AVERROR_INVALIDDATA;
106 
107  avio_skip(pb, 2); /* encoding method */
108  sound_rate = avio_rl16(pb);
109  rate = avio_rl16(pb);
110  channels = avio_rl16(pb);
111  def_sound_size = avio_rl16(pb);
112 
113  /** setup video stream */
114  st = avformat_new_stream(s, NULL);
115  if(!st)
116  return AVERROR(ENOMEM);
117 
120  st->codecpar->codec_tag = 0; /* no fourcc */
121  st->codecpar->width = 320;
122  st->codecpar->height = 200;
123 
124  /** allocate and fill extradata */
126 
127  if(signature == RLV3_TAG && back_size > 0)
128  st->codecpar->extradata_size += back_size;
129 
130  ret = ff_get_extradata(s, st->codecpar, pb, st->codecpar->extradata_size);
131  if (ret < 0)
132  return ret;
133 
134  /** setup audio stream if present */
135  if(sound_rate){
136  if (!channels || channels > 42) {
137  av_log(s, AV_LOG_ERROR, "Invalid number of channels: %d\n", channels);
138  return AVERROR_INVALIDDATA;
139  }
140 
141  pts_num = def_sound_size;
142  pts_den = rate;
143 
144  st = avformat_new_stream(s, NULL);
145  if (!st)
146  return AVERROR(ENOMEM);
149  st->codecpar->codec_tag = 1;
150  st->codecpar->channels = channels;
152  st->codecpar->sample_rate = rate;
155  st->codecpar->block_align = st->codecpar->channels *
157  avpriv_set_pts_info(st,32,1,rate);
158  }
159 
160  avpriv_set_pts_info(s->streams[0], 32, pts_num, pts_den);
161 
162  chunk_size = av_malloc(frame_count * sizeof(uint32_t));
163  audio_size = av_malloc(frame_count * sizeof(uint32_t));
164  chunk_offset = av_malloc(frame_count * sizeof(uint32_t));
165 
166  if(!chunk_size || !audio_size || !chunk_offset){
167  av_free(chunk_size);
168  av_free(audio_size);
169  av_free(chunk_offset);
170  return AVERROR(ENOMEM);
171  }
172 
173  /** read offset and size tables */
174  for(i=0; i < frame_count;i++) {
175  if (avio_feof(pb)) {
176  ret = AVERROR_INVALIDDATA;
177  goto end;
178  }
179  chunk_size[i] = avio_rl32(pb);
180  }
181  for(i=0; i < frame_count;i++) {
182  if (avio_feof(pb)) {
183  ret = AVERROR_INVALIDDATA;
184  goto end;
185  }
186  chunk_offset[i] = avio_rl32(pb);
187  }
188  for(i=0; i < frame_count;i++) {
189  if (avio_feof(pb)) {
190  ret = AVERROR_INVALIDDATA;
191  goto end;
192  }
193  audio_size[i] = avio_rl32(pb) & 0xFFFF;
194  }
195 
196  /** build the sample index */
197  for(i=0;i<frame_count;i++){
198  if(chunk_size[i] < 0 || audio_size[i] > chunk_size[i]){
199  ret = AVERROR_INVALIDDATA;
200  break;
201  }
202 
203  if(sound_rate && audio_size[i]){
204  av_add_index_entry(s->streams[1], chunk_offset[i],
205  audio_frame_counter,audio_size[i], 0, AVINDEX_KEYFRAME);
206  audio_frame_counter += audio_size[i] / channels;
207  }
208  av_add_index_entry(s->streams[0], chunk_offset[i] + audio_size[i],
209  video_frame_counter,chunk_size[i]-audio_size[i],0,AVINDEX_KEYFRAME);
210  ++video_frame_counter;
211  }
212 
213 end:
214  av_free(chunk_size);
215  av_free(audio_size);
216  av_free(chunk_offset);
217 
218  return ret;
219 }
220 
221 /**
222  * read a single audio or video packet
223  * @param s demuxer context
224  * @param pkt the packet to be filled
225  * @return 0 on success, AVERROR otherwise
226  */
228  AVPacket *pkt)
229 {
230  Rl2DemuxContext *rl2 = s->priv_data;
231  AVIOContext *pb = s->pb;
233  int i;
234  int ret = 0;
235  int stream_id = -1;
236  int64_t pos = INT64_MAX;
237 
238  /** check if there is a valid video or audio entry that can be used */
239  for(i=0; i<s->nb_streams; i++){
240  if(rl2->index_pos[i] < s->streams[i]->nb_index_entries
241  && s->streams[i]->index_entries[ rl2->index_pos[i] ].pos < pos){
242  sample = &s->streams[i]->index_entries[ rl2->index_pos[i] ];
243  pos= sample->pos;
244  stream_id= i;
245  }
246  }
247 
248  if(stream_id == -1)
249  return AVERROR_EOF;
250 
251  ++rl2->index_pos[stream_id];
252 
253  /** position the stream (will probably be there anyway) */
254  avio_seek(pb, sample->pos, SEEK_SET);
255 
256  /** fill the packet */
257  ret = av_get_packet(pb, pkt, sample->size);
258  if(ret != sample->size){
259  return AVERROR(EIO);
260  }
261 
262  pkt->stream_index = stream_id;
263  pkt->pts = sample->timestamp;
264 
265  return ret;
266 }
267 
268 /**
269  * seek to a new timestamp
270  * @param s demuxer context
271  * @param stream_index index of the stream that should be seeked
272  * @param timestamp wanted timestamp
273  * @param flags direction and seeking mode
274  * @return 0 on success, -1 otherwise
275  */
276 static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
277 {
278  AVStream *st = s->streams[stream_index];
279  Rl2DemuxContext *rl2 = s->priv_data;
280  int i;
281  int index = av_index_search_timestamp(st, timestamp, flags);
282  if(index < 0)
283  return -1;
284 
285  rl2->index_pos[stream_index] = index;
286  timestamp = st->index_entries[index].timestamp;
287 
288  for(i=0; i < s->nb_streams; i++){
289  AVStream *st2 = s->streams[i];
290  index = av_index_search_timestamp(st2,
291  av_rescale_q(timestamp, st->time_base, st2->time_base),
292  flags | AVSEEK_FLAG_BACKWARD);
293 
294  if(index < 0)
295  index = 0;
296 
297  rl2->index_pos[i] = index;
298  }
299 
300  return 0;
301 }
302 
304  .name = "rl2",
305  .long_name = NULL_IF_CONFIG_SMALL("RL2"),
306  .priv_data_size = sizeof(Rl2DemuxContext),
311 };
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2513
#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 rl2_probe(const AVProbeData *p)
check if the file is in rl2 format
Definition: rl2.c:58
int av_add_index_entry(AVStream *st, int64_t pos, int64_t timestamp, int size, int distance, int flags)
Add an index entry into a sorted list.
Definition: utils.c:2045
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:4938
int64_t pos
Definition: avformat.h:805
static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
seek to a new timestamp
Definition: rl2.c:276
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1105
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:341
static AVPacket pkt
#define sample
AVInputFormat ff_rl2_demuxer
Definition: rl2.c:303
Format I/O context.
Definition: avformat.h:1351
static const char signature[]
Definition: ipmovie.c:615
#define av_cold
Definition: attributes.h:88
#define av_malloc(s)
int width
Video only.
Definition: codec_par.h:126
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:790
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4519
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:87
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
#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:304
channels
Definition: aptx.h:33
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
#define AVINDEX_KEYFRAME
Definition: avformat.h:812
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2162
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:806
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
unsigned int pos
Definition: spdifenc.c:410
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1407
int block_align
Audio only.
Definition: codec_par.h:177
#define s(width, name)
Definition: cbs_vp9.c:257
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
Stream structure.
Definition: avformat.h:876
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
#define FORM_TAG
Definition: rl2.c:44
static int rl2_read_packet(AVFormatContext *s, AVPacket *pkt)
read a single audio or video packet
Definition: rl2.c:227
#define RLV2_TAG
Definition: rl2.c:45
int nb_index_entries
Definition: avformat.h:1107
int index
Definition: gxfenc.c:89
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
#define RLV3_TAG
Definition: rl2.c:46
#define flags(name, subs,...)
Definition: cbs_av1.c:560
#define EXTRADATA1_SIZE
video base, clr, palette
Definition: rl2.c:42
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
static av_cold int rl2_read_header(AVFormatContext *s)
read rl2 header data and setup the avstreams
Definition: rl2.c:76
int sample_rate
Audio only.
Definition: codec_par.h:170
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:743
Main libavformat public API header.
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
unsigned int index_pos[2]
indexes in the sample tables
Definition: rl2.c:49
#define av_free(p)
void * priv_data
Format private data.
Definition: avformat.h:1379
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
int channels
Audio only.
Definition: codec_par.h:166
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:368
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
int stream_index
Definition: packet.h:357
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:905
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
This structure stores compressed data.
Definition: packet.h:332
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:348
int i
Definition: input.c:406