FFmpeg: libavformat/rl2.c Source File

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 "demux.h"
41 #include "internal.h"
42 
43  #define EXTRADATA1_SIZE (6 + 256 * 3) ///< video base, clr, palette
44 
45  #define FORM_TAG MKBETAG('F', 'O', 'R', 'M')
46  #define RLV2_TAG MKBETAG('R', 'L', 'V', '2')
47  #define RLV3_TAG MKBETAG('R', 'L', 'V', '3')
48 
49  typedef struct Rl2DemuxContext {
50   unsigned int index_pos[2]; ///< indexes in the sample tables
51 } Rl2DemuxContext;
52 
53 
54 /**
55  * check if the file is in rl2 format
56  * @param p probe buffer
57  * @return 0 when the probe buffer does not contain rl2 data, > 0 otherwise
58  */
59  static int rl2_probe(const AVProbeData *p)
60 {
61 
62  if(AV_RB32(&p->buf[0]) != FORM_TAG)
63  return 0;
64 
65  if(AV_RB32(&p->buf[8]) != RLV2_TAG &&
66  AV_RB32(&p->buf[8]) != RLV3_TAG)
67  return 0;
68 
69  return AVPROBE_SCORE_MAX;
70 }
71 
72 /**
73  * read rl2 header data and setup the avstreams
74  * @param s demuxer context
75  * @return 0 on success, AVERROR otherwise
76  */
77  static av_cold int rl2_read_header(AVFormatContext *s)
78 {
79  AVIOContext *pb = s->pb;
80  AVStream *st;
81  unsigned int frame_count;
82  unsigned int audio_frame_counter = 0;
83  unsigned int video_frame_counter = 0;
84  unsigned int back_size;
85  unsigned short sound_rate;
86  unsigned short rate;
87  unsigned short channels;
88  unsigned short def_sound_size;
89  unsigned int signature;
90  unsigned int pts_den = 11025; /* video only case */
91  unsigned int pts_num = 1103;
92  unsigned int* chunk_offset = NULL;
93  int* chunk_size = NULL;
94  int* audio_size = NULL;
95  int i;
96  int ret = 0;
97 
98  avio_skip(pb,4); /* skip FORM tag */
99  back_size = avio_rl32(pb); /**< get size of the background frame */
100  signature = avio_rb32(pb);
101  avio_skip(pb, 4); /* data size */
102  frame_count = avio_rl32(pb);
103 
104  /* disallow back_sizes and frame_counts that may lead to overflows later */
105  if(back_size > INT_MAX/2 || frame_count > INT_MAX / sizeof(uint32_t))
106  return AVERROR_INVALIDDATA;
107 
108  avio_skip(pb, 2); /* encoding method */
109  sound_rate = avio_rl16(pb);
110  rate = avio_rl16(pb);
111  channels = avio_rl16(pb);
112  def_sound_size = avio_rl16(pb);
113 
114  /** setup video stream */
115  st = avformat_new_stream(s, NULL);
116  if(!st)
117  return AVERROR(ENOMEM);
118 
119  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
120  st->codecpar->codec_id = AV_CODEC_ID_RL2;
121  st->codecpar->codec_tag = 0; /* no fourcc */
122  st->codecpar->width = 320;
123  st->codecpar->height = 200;
124 
125  /** allocate and fill extradata */
126  st->codecpar->extradata_size = EXTRADATA1_SIZE;
127 
128  if(signature == RLV3_TAG && back_size > 0)
129  st->codecpar->extradata_size += back_size;
130 
131  ret = ff_get_extradata(s, st->codecpar, pb, st->codecpar->extradata_size);
132  if (ret < 0)
133  return ret;
134 
135  /** setup audio stream if present */
136  if(sound_rate){
137  if (!channels || channels > 42) {
138  av_log(s, AV_LOG_ERROR, "Invalid number of channels: %d\n", channels);
139  return AVERROR_INVALIDDATA;
140  }
141 
142  pts_num = def_sound_size;
143  pts_den = rate;
144 
145  st = avformat_new_stream(s, NULL);
146  if (!st)
147  return AVERROR(ENOMEM);
148  st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
149  st->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
150  st->codecpar->codec_tag = 1;
151  st->codecpar->ch_layout.nb_channels = channels;
152  st->codecpar->bits_per_coded_sample = 8;
153  st->codecpar->sample_rate = rate;
154  st->codecpar->bit_rate = channels * st->codecpar->sample_rate *
155  st->codecpar->bits_per_coded_sample;
156  st->codecpar->block_align = channels *
157  st->codecpar->bits_per_coded_sample / 8;
158  avpriv_set_pts_info(st,32,1,rate);
159  }
160 
161  avpriv_set_pts_info(s->streams[0], 32, pts_num, pts_den);
162 
163  chunk_size = av_malloc(frame_count * sizeof(uint32_t));
164  audio_size = av_malloc(frame_count * sizeof(uint32_t));
165  chunk_offset = av_malloc(frame_count * sizeof(uint32_t));
166 
167  if(!chunk_size || !audio_size || !chunk_offset){
168  av_free(chunk_size);
169  av_free(audio_size);
170  av_free(chunk_offset);
171  return AVERROR(ENOMEM);
172  }
173 
174  /** read offset and size tables */
175  for(i=0; i < frame_count;i++) {
176  if (avio_feof(pb)) {
177  ret = AVERROR_INVALIDDATA;
178  goto end;
179  }
180  chunk_size[i] = avio_rl32(pb);
181  }
182  for(i=0; i < frame_count;i++) {
183  if (avio_feof(pb)) {
184  ret = AVERROR_INVALIDDATA;
185  goto end;
186  }
187  chunk_offset[i] = avio_rl32(pb);
188  }
189  for(i=0; i < frame_count;i++) {
190  if (avio_feof(pb)) {
191  ret = AVERROR_INVALIDDATA;
192  goto end;
193  }
194  audio_size[i] = avio_rl32(pb) & 0xFFFF;
195  }
196 
197  /** build the sample index */
198  for(i=0;i<frame_count;i++){
199  if(chunk_size[i] < 0 || audio_size[i] > chunk_size[i]){
200  ret = AVERROR_INVALIDDATA;
201  break;
202  }
203 
204  if(sound_rate && audio_size[i]){
205  av_add_index_entry(s->streams[1], chunk_offset[i],
206  audio_frame_counter,audio_size[i], 0, AVINDEX_KEYFRAME);
207  audio_frame_counter += audio_size[i] / channels;
208  }
209  av_add_index_entry(s->streams[0], chunk_offset[i] + audio_size[i],
210  video_frame_counter,chunk_size[i]-audio_size[i],0,AVINDEX_KEYFRAME);
211  ++video_frame_counter;
212  }
213 
214 end:
215  av_free(chunk_size);
216  av_free(audio_size);
217  av_free(chunk_offset);
218 
219  return ret;
220 }
221 
222 /**
223  * read a single audio or video packet
224  * @param s demuxer context
225  * @param pkt the packet to be filled
226  * @return 0 on success, AVERROR otherwise
227  */
228  static int rl2_read_packet(AVFormatContext *s,
229  AVPacket *pkt)
230 {
231  Rl2DemuxContext *rl2 = s->priv_data;
232  AVIOContext *pb = s->pb;
233  AVIndexEntry *sample = NULL;
234  int i;
235  int ret = 0;
236  int stream_id = -1;
237  int64_t pos = INT64_MAX;
238 
239  /** check if there is a valid video or audio entry that can be used */
240  for(i=0; i<s->nb_streams; i++){
241  const FFStream *const sti = ffstream(s->streams[i]);
242  if (rl2->index_pos[i] < sti->nb_index_entries
243  && sti->index_entries[ rl2->index_pos[i] ].pos < pos) {
244  sample = &sti->index_entries[ rl2->index_pos[i] ];
245  pos= sample->pos;
246  stream_id= i;
247  }
248  }
249 
250  if(stream_id == -1)
251  return AVERROR_EOF;
252 
253  ++rl2->index_pos[stream_id];
254 
255  /** position the stream (will probably be there anyway) */
256  avio_seek(pb, sample->pos, SEEK_SET);
257 
258  /** fill the packet */
259  ret = av_get_packet(pb, pkt, sample->size);
260  if(ret != sample->size){
261  return AVERROR(EIO);
262  }
263 
264  pkt->stream_index = stream_id;
265  pkt->pts = sample->timestamp;
266 
267  return ret;
268 }
269 
270 /**
271  * seek to a new timestamp
272  * @param s demuxer context
273  * @param stream_index index of the stream that should be seeked
274  * @param timestamp wanted timestamp
275  * @param flags direction and seeking mode
276  * @return 0 on success, -1 otherwise
277  */
278  static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
279 {
280  AVStream *st = s->streams[stream_index];
281  Rl2DemuxContext *rl2 = s->priv_data;
282  int i;
283  int index = av_index_search_timestamp(st, timestamp, flags);
284  if(index < 0)
285  return -1;
286 
287  rl2->index_pos[stream_index] = index;
288  timestamp = ffstream(st)->index_entries[index].timestamp;
289 
290  for(i=0; i < s->nb_streams; i++){
291  AVStream *st2 = s->streams[i];
292  index = av_index_search_timestamp(st2,
293  av_rescale_q(timestamp, st->time_base, st2->time_base),
294  flags | AVSEEK_FLAG_BACKWARD);
295 
296  if(index < 0)
297  index = 0;
298 
299  rl2->index_pos[i] = index;
300  }
301 
302  return 0;
303 }
304 
305  const AVInputFormat ff_rl2_demuxer = {
306  .name = "rl2",
307  .long_name = NULL_IF_CONFIG_SMALL("RL2"),
308  .priv_data_size = sizeof(Rl2DemuxContext),
309  .read_probe = rl2_probe,
310  .read_header = rl2_read_header,
311  .read_packet = rl2_read_packet,
312  .read_seek = rl2_read_seek,
313 };
ff_rl2_demuxer
const AVInputFormat ff_rl2_demuxer
Definition: rl2.c:305
AVERROR
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
FORM_TAG
#define FORM_TAG
Definition: rl2.c:45
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
rl2_read_header
static av_cold int rl2_read_header(AVFormatContext *s)
read rl2 header data and setup the avstreams
Definition: rl2.c:77
rl2_read_seek
static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
seek to a new timestamp
Definition: rl2.c:278
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:65
mathematics.h
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:300
AVIndexEntry
Definition: avformat.h:807
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
AVINDEX_KEYFRAME
#define AVINDEX_KEYFRAME
Definition: avformat.h:815
ff_get_extradata
int ff_get_extradata(void *logctx, 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: demux_utils.c:355
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:697
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:407
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
av_add_index_entry
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: seek.c:118
rl2_probe
static int rl2_probe(const AVProbeData *p)
check if the file is in rl2 format
Definition: rl2.c:59
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:743
signature
static const char signature[]
Definition: ipmovie.c:591
avio_rb32
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:790
pkt
AVPacket * pkt
Definition: movenc.c:59
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AVInputFormat
Definition: avformat.h:656
av_cold
#define av_cold
Definition: attributes.h:90
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
AV_CODEC_ID_RL2
@ AV_CODEC_ID_RL2
Definition: codec_id.h:164
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:127
AVIndexEntry::timestamp
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:809
channels
channels
Definition: aptx.h:32
av_rescale_q
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
EXTRADATA1_SIZE
#define EXTRADATA1_SIZE
video base, clr, palette
Definition: rl2.c:43
AVFormatContext
Format I/O context.
Definition: avformat.h:1213
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
AVSEEK_FLAG_BACKWARD
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2289
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:532
AVStream::time_base
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented.
Definition: avformat.h:978
NULL
#define NULL
Definition: coverity.c:32
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
FFStream::nb_index_entries
int nb_index_entries
Definition: internal.h:254
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
index
int index
Definition: gxfenc.c:89
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:177
AVCodecParameters::extradata_size
int extradata_size
Size of the extradata content in bytes.
Definition: codec_par.h:79
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
FFStream
Definition: internal.h:197
Rl2DemuxContext
Definition: rl2.c:49
Rl2DemuxContext::index_pos
unsigned int index_pos[2]
indexes in the sample tables
Definition: rl2.c:50
sample
#define sample
Definition: flacdsp_template.c:44
AV_RB32
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:96
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:367
AVCodecParameters::height
int height
Definition: codec_par.h:128
AVCodecParameters::block_align
int block_align
Audio only.
Definition: codec_par.h:184
demux.h
RLV3_TAG
#define RLV3_TAG
Definition: rl2.c:47
av_get_packet
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:102
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
AVStream
Stream structure.
Definition: avformat.h:948
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
pos
unsigned int pos
Definition: spdifenc.c:412
avformat.h
AVIndexEntry::pos
int64_t pos
Definition: avformat.h:808
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
FFStream::index_entries
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: internal.h:252
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:103
AV_CODEC_ID_PCM_U8
@ AV_CODEC_ID_PCM_U8
Definition: codec_id.h:323
RLV2_TAG
#define RLV2_TAG
Definition: rl2.c:46
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVCodecParameters::bit_rate
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: codec_par.h:90
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
rl2_read_packet
static int rl2_read_packet(AVFormatContext *s, AVPacket *pkt)
read a single audio or video packet
Definition: rl2.c:228
av_index_search_timestamp
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: seek.c:238
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:375
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