FFmpeg  4.4
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];
291  av_rescale_q(timestamp, st->time_base, st2->time_base),
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 };
channels
Definition: aptx.h:33
#define av_cold
Definition: attributes.h:88
Main libavformat public API header.
#define AVINDEX_KEYFRAME
Definition: avformat.h:811
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2415
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:364
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:734
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
#define AV_RB32
Definition: intreadwrite.h:130
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#define s(width, name)
Definition: cbs_vp9.c:257
#define NULL
Definition: coverity.c:32
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
#define sample
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:318
@ AV_CODEC_ID_RL2
Definition: codec_id.h:163
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4505
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:2011
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2128
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
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
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
int index
Definition: gxfenc.c:89
int i
Definition: input.c:407
static const char signature[]
Definition: ipmovie.c:615
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:4941
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:3330
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
#define RLV2_TAG
Definition: rl2.c:45
AVInputFormat ff_rl2_demuxer
Definition: rl2.c:303
static int rl2_probe(const AVProbeData *p)
check if the file is in rl2 format
Definition: rl2.c:58
static int rl2_read_packet(AVFormatContext *s, AVPacket *pkt)
read a single audio or video packet
Definition: rl2.c:227
static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
seek to a new timestamp
Definition: rl2.c:276
#define RLV3_TAG
Definition: rl2.c:46
static av_cold int rl2_read_header(AVFormatContext *s)
read rl2 header data and setup the avstreams
Definition: rl2.c:76
#define FORM_TAG
Definition: rl2.c:44
#define EXTRADATA1_SIZE
video base, clr, palette
Definition: rl2.c:42
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
unsigned int pos
Definition: spdifenc.c:412
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:78
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
int width
Video only.
Definition: codec_par.h:126
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:89
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
int block_align
Audio only.
Definition: codec_par.h:177
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:64
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int sample_rate
Audio only.
Definition: codec_par.h:170
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:805
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:902
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1090
unsigned int index_pos[2]
indexes in the sample tables
Definition: rl2.c:49
#define av_free(p)
#define av_malloc(s)
#define av_log(a,...)
AVPacket * pkt
Definition: movenc.c:59