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  if(ff_get_extradata(s, st->codecpar, pb, st->codecpar->extradata_size) < 0)
131  return AVERROR(ENOMEM);
132 
133  /** setup audio stream if present */
134  if(sound_rate){
135  if (!channels || channels > 42) {
136  av_log(s, AV_LOG_ERROR, "Invalid number of channels: %d\n", channels);
137  return AVERROR_INVALIDDATA;
138  }
139 
140  pts_num = def_sound_size;
141  pts_den = rate;
142 
143  st = avformat_new_stream(s, NULL);
144  if (!st)
145  return AVERROR(ENOMEM);
148  st->codecpar->codec_tag = 1;
149  st->codecpar->channels = channels;
151  st->codecpar->sample_rate = rate;
154  st->codecpar->block_align = st->codecpar->channels *
156  avpriv_set_pts_info(st,32,1,rate);
157  }
158 
159  avpriv_set_pts_info(s->streams[0], 32, pts_num, pts_den);
160 
161  chunk_size = av_malloc(frame_count * sizeof(uint32_t));
162  audio_size = av_malloc(frame_count * sizeof(uint32_t));
163  chunk_offset = av_malloc(frame_count * sizeof(uint32_t));
164 
165  if(!chunk_size || !audio_size || !chunk_offset){
166  av_free(chunk_size);
167  av_free(audio_size);
168  av_free(chunk_offset);
169  return AVERROR(ENOMEM);
170  }
171 
172  /** read offset and size tables */
173  for(i=0; i < frame_count;i++) {
174  if (avio_feof(pb))
175  return AVERROR_INVALIDDATA;
176  chunk_size[i] = avio_rl32(pb);
177  }
178  for(i=0; i < frame_count;i++) {
179  if (avio_feof(pb))
180  return AVERROR_INVALIDDATA;
181  chunk_offset[i] = avio_rl32(pb);
182  }
183  for(i=0; i < frame_count;i++) {
184  if (avio_feof(pb))
185  return AVERROR_INVALIDDATA;
186  audio_size[i] = avio_rl32(pb) & 0xFFFF;
187  }
188 
189  /** build the sample index */
190  for(i=0;i<frame_count;i++){
191  if(chunk_size[i] < 0 || audio_size[i] > chunk_size[i]){
192  ret = AVERROR_INVALIDDATA;
193  break;
194  }
195 
196  if(sound_rate && audio_size[i]){
197  av_add_index_entry(s->streams[1], chunk_offset[i],
198  audio_frame_counter,audio_size[i], 0, AVINDEX_KEYFRAME);
199  audio_frame_counter += audio_size[i] / channels;
200  }
201  av_add_index_entry(s->streams[0], chunk_offset[i] + audio_size[i],
202  video_frame_counter,chunk_size[i]-audio_size[i],0,AVINDEX_KEYFRAME);
203  ++video_frame_counter;
204  }
205 
206 
207  av_free(chunk_size);
208  av_free(audio_size);
209  av_free(chunk_offset);
210 
211  return ret;
212 }
213 
214 /**
215  * read a single audio or video packet
216  * @param s demuxer context
217  * @param pkt the packet to be filled
218  * @return 0 on success, AVERROR otherwise
219  */
221  AVPacket *pkt)
222 {
223  Rl2DemuxContext *rl2 = s->priv_data;
224  AVIOContext *pb = s->pb;
226  int i;
227  int ret = 0;
228  int stream_id = -1;
229  int64_t pos = INT64_MAX;
230 
231  /** check if there is a valid video or audio entry that can be used */
232  for(i=0; i<s->nb_streams; i++){
233  if(rl2->index_pos[i] < s->streams[i]->nb_index_entries
234  && s->streams[i]->index_entries[ rl2->index_pos[i] ].pos < pos){
235  sample = &s->streams[i]->index_entries[ rl2->index_pos[i] ];
236  pos= sample->pos;
237  stream_id= i;
238  }
239  }
240 
241  if(stream_id == -1)
242  return AVERROR_EOF;
243 
244  ++rl2->index_pos[stream_id];
245 
246  /** position the stream (will probably be there anyway) */
247  avio_seek(pb, sample->pos, SEEK_SET);
248 
249  /** fill the packet */
250  ret = av_get_packet(pb, pkt, sample->size);
251  if(ret != sample->size){
252  av_packet_unref(pkt);
253  return AVERROR(EIO);
254  }
255 
256  pkt->stream_index = stream_id;
257  pkt->pts = sample->timestamp;
258 
259  return ret;
260 }
261 
262 /**
263  * seek to a new timestamp
264  * @param s demuxer context
265  * @param stream_index index of the stream that should be seeked
266  * @param timestamp wanted timestamp
267  * @param flags direction and seeking mode
268  * @return 0 on success, -1 otherwise
269  */
270 static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
271 {
272  AVStream *st = s->streams[stream_index];
273  Rl2DemuxContext *rl2 = s->priv_data;
274  int i;
275  int index = av_index_search_timestamp(st, timestamp, flags);
276  if(index < 0)
277  return -1;
278 
279  rl2->index_pos[stream_index] = index;
280  timestamp = st->index_entries[index].timestamp;
281 
282  for(i=0; i < s->nb_streams; i++){
283  AVStream *st2 = s->streams[i];
284  index = av_index_search_timestamp(st2,
285  av_rescale_q(timestamp, st->time_base, st2->time_base),
286  flags | AVSEEK_FLAG_BACKWARD);
287 
288  if(index < 0)
289  index = 0;
290 
291  rl2->index_pos[i] = index;
292  }
293 
294  return 0;
295 }
296 
298  .name = "rl2",
299  .long_name = NULL_IF_CONFIG_SMALL("RL2"),
300  .priv_data_size = sizeof(Rl2DemuxContext),
305 };
#define AVSEEK_FLAG_BACKWARD
Definition: avformat.h:2511
#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:2043
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:4896
int64_t pos
Definition: avformat.h:810
static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
seek to a new timestamp
Definition: rl2.c:270
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:3960
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
AVIndexEntry * index_entries
Only used if the format does not support seeking natively.
Definition: avformat.h:1110
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
static AVPacket pkt
#define sample
AVInputFormat ff_rl2_demuxer
Definition: rl2.c:297
Format I/O context.
Definition: avformat.h:1358
static const char signature[]
Definition: ipmovie.c:615
#define av_cold
Definition: attributes.h:82
#define av_malloc(s)
int width
Video only.
Definition: avcodec.h:4026
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:803
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4469
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:1426
#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
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3989
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:817
#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
int av_index_search_timestamp(AVStream *st, int64_t timestamp, int flags)
Get the index for a specific timestamp.
Definition: utils.c:2158
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:772
int64_t timestamp
Timestamp in AVStream.time_base units, preferably the time from which on correctly decoded frames are...
Definition: avformat.h:811
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3956
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3978
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
int block_align
Audio only.
Definition: avcodec.h:4077
#define s(width, name)
Definition: cbs_vp9.c:257
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
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
#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:220
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
#define RLV2_TAG
Definition: rl2.c:45
int nb_index_entries
Definition: avformat.h:1112
int index
Definition: gxfenc.c:89
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
#define RLV3_TAG
Definition: rl2.c:46
#define flags(name, subs,...)
Definition: cbs_av1.c:561
#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: avcodec.h:4070
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:756
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:3316
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:1386
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: avcodec.h:4002
int channels
Audio only.
Definition: avcodec.h:4066
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
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:3964
int stream_index
Definition: avcodec.h:1482
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avformat.h:910
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: avcodec.h:1457
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1473