FFmpeg
cdxl.c
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1 /*
2  * CDXL demuxer
3  * Copyright (c) 2011-2012 Paul B Mahol
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 
23 #include "libavutil/intreadwrite.h"
24 #include "libavutil/parseutils.h"
25 #include "libavutil/opt.h"
26 #include "avformat.h"
27 #include "demux.h"
28 #include "internal.h"
29 
30 #define CDXL_HEADER_SIZE 32
31 
32 typedef struct CDXLDemuxContext {
33  AVClass *class;
36  int srate;
42  int64_t filesize;
43  int64_t pos;
45 
46 static int cdxl_read_probe(const AVProbeData *p)
47 {
48  int score = AVPROBE_SCORE_EXTENSION + 10;
49  const uint8_t *buf = p->buf;
50 
51  if (p->buf_size < CDXL_HEADER_SIZE)
52  return 0;
53 
54  /* check type */
55  if (buf[0] > 1)
56  return 0;
57 
58  /* reserved bytes should always be set to 0 */
59  if (AV_RL24(&buf[29]))
60  return 0;
61 
62  /* check palette size */
63  if (!AV_RN16(&buf[20]))
64  return 0;
65  if (buf[0] == 1 && AV_RB16(&buf[20]) > 512)
66  return 0;
67  if (buf[0] == 0 && AV_RB16(&buf[20]) > 768)
68  return 0;
69 
70  if (!AV_RN16(&buf[22]) && AV_RN16(&buf[24]))
71  return 0;
72 
73  if (buf[0] == 0 && (!buf[26] || !AV_RB16(&buf[24])))
74  return 0;
75 
76  /* check number of planes */
77  if (buf[19] != 6 && buf[19] != 8 && buf[19] != 24)
78  return 0;
79 
80  if (buf[18])
81  return 0;
82 
83  /* check widh and height */
84  if (AV_RB16(&buf[14]) > 640 || AV_RB16(&buf[16]) > 480 ||
85  AV_RB16(&buf[14]) == 0 || AV_RB16(&buf[16]) == 0)
86  return 0;
87 
88  /* chunk size */
89  if (AV_RB32(&buf[2]) <= AV_RB16(&buf[20]) + AV_RB16(&buf[22]) * (1 + !!(buf[1] & 0x10)) + CDXL_HEADER_SIZE)
90  return 0;
91 
92  /* previous chunk size */
93  if (AV_RN32(&buf[6]))
94  score /= 2;
95 
96  /* current frame number, usually starts from 1 */
97  if (AV_RB32(&buf[10]) != 1)
98  score /= 2;
99 
100  return score;
101 }
102 
104 {
105  CDXLDemuxContext *cdxl = s->priv_data;
106 
107  cdxl->read_chunk = 0;
108  cdxl->video_stream_index = -1;
109  cdxl->audio_stream_index = -1;
110 
111  cdxl->filesize = avio_size(s->pb);
112 
113  s->ctx_flags |= AVFMTCTX_NOHEADER;
114 
115  return 0;
116 }
117 
119 {
120  CDXLDemuxContext *cdxl = s->priv_data;
121  AVIOContext *pb = s->pb;
122  uint32_t current_size, video_size, image_size;
123  uint16_t audio_size, palette_size, width, height;
124  int channels, type, format, ret;
125 
126  if (avio_feof(pb))
127  return AVERROR_EOF;
128 
129  if (!cdxl->read_chunk) {
130  cdxl->pos = avio_tell(pb);
132  return AVERROR_EOF;
133  }
134  if (cdxl->header[0] > 1) {
135  av_log(s, AV_LOG_ERROR, "unsupported cdxl file\n");
136  return AVERROR_INVALIDDATA;
137  }
138 
139  type = cdxl->header[0];
140  channels = 1 + !!(cdxl->header[1] & 0x10);
141  format = cdxl->header[1] & 0xE0;
142  current_size = AV_RB32(&cdxl->header[2]);
143  width = AV_RB16(&cdxl->header[14]);
144  height = AV_RB16(&cdxl->header[16]);
145  palette_size = AV_RB16(&cdxl->header[20]);
146  audio_size = AV_RB16(&cdxl->header[22]) * channels;
147  cdxl->srate = AV_RB16(&cdxl->header[24]);
148  if (!cdxl->srate && audio_size)
149  cdxl->srate = cdxl->sample_rate;
150  cdxl->frate.num = cdxl->header[26];
151  cdxl->frate.den = 1;
152  if (cdxl->header[19] == 0 ||
153  FFALIGN(width, 16) * (uint64_t)height * cdxl->header[19] > INT_MAX)
154  return AVERROR_INVALIDDATA;
155  if (format == 0x20)
156  image_size = width * height * cdxl->header[19] / 8;
157  else
158  image_size = FFALIGN(width, 16) * height * cdxl->header[19] / 8;
159  video_size = palette_size + image_size;
160 
161  if ((type == 1 && palette_size > 512) ||
162  (type == 0 && palette_size > 768))
163  return AVERROR_INVALIDDATA;
164  if (current_size < (uint64_t)audio_size + video_size + CDXL_HEADER_SIZE)
165  return AVERROR_INVALIDDATA;
166 
167  if (!cdxl->frate.num && audio_size && cdxl->srate > 0) {
168  cdxl->frate = (AVRational){ cdxl->srate, audio_size };
169  } else if (!cdxl->frate.num) {
170  cdxl->frate = cdxl->frame_rate;
171  }
172 
173  if (cdxl->read_chunk && audio_size) {
174  if (cdxl->audio_stream_index == -1) {
176  if (!st)
177  return AVERROR(ENOMEM);
178 
180  st->codecpar->codec_tag = 0;
183  st->codecpar->sample_rate= cdxl->srate;
184  st->start_time = 0;
185  cdxl->audio_stream_index = st->index;
186  avpriv_set_pts_info(st, 64, 1, cdxl->srate);
187  if (current_size && cdxl->filesize > 0 && audio_size > 0)
188  st->duration = (cdxl->filesize / current_size) * audio_size / channels;
189  }
190 
191  ret = av_get_packet(pb, pkt, audio_size);
192  if (ret < 0)
193  return ret;
195  pkt->pos = cdxl->pos;
196  pkt->duration = audio_size / channels;
197  cdxl->read_chunk = 0;
198  } else {
199  if (cdxl->video_stream_index == -1) {
201  if (!st)
202  return AVERROR(ENOMEM);
203 
205  st->codecpar->codec_tag = 0;
207  st->codecpar->width = width;
208  st->codecpar->height = height;
209 
210  if (current_size && cdxl->filesize > 0)
211  st->nb_frames = cdxl->filesize / current_size;
212  st->start_time = 0;
213  cdxl->video_stream_index = st->index;
214  avpriv_set_pts_info(st, 64, cdxl->frate.den, cdxl->frate.num);
215  }
216 
217  if ((ret = av_new_packet(pkt, video_size + CDXL_HEADER_SIZE)) < 0)
218  return ret;
219  memcpy(pkt->data, cdxl->header, CDXL_HEADER_SIZE);
220  ret = avio_read(pb, pkt->data + CDXL_HEADER_SIZE, video_size);
221  if (ret < 0) {
222  return ret;
223  }
227  pkt->pos = cdxl->pos;
228  pkt->duration = 1;
229  cdxl->read_chunk = audio_size;
230  }
231 
232  if (!cdxl->read_chunk)
233  avio_skip(pb, current_size - audio_size - video_size - CDXL_HEADER_SIZE);
234  return ret;
235 }
236 
237 static int read_seek(AVFormatContext *s, int stream_index,
238  int64_t timestamp, int flags)
239 {
240  CDXLDemuxContext *cdxl = s->priv_data;
241 
242  cdxl->read_chunk = 0;
243 
244  return -1;
245 }
246 
247 #define OFFSET(x) offsetof(CDXLDemuxContext, x)
248 static const AVOption cdxl_options[] = {
249  { "sample_rate", "", OFFSET(sample_rate), AV_OPT_TYPE_INT, { .i64=11025 }, 8000, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
250  { "frame_rate", "", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, { .str="15" }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
251  { NULL },
252 };
253 
254 static const AVClass cdxl_demuxer_class = {
255  .class_name = "CDXL demuxer",
256  .item_name = av_default_item_name,
257  .option = cdxl_options,
258  .version = LIBAVUTIL_VERSION_INT,
259 };
260 
262  .p.name = "cdxl",
263  .p.long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),
264  .p.priv_class = &cdxl_demuxer_class,
265  .p.extensions = "cdxl,xl",
266  .p.flags = AVFMT_GENERIC_INDEX,
267  .priv_data_size = sizeof(CDXLDemuxContext),
271  .read_seek = read_seek,
272 };
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
CDXLDemuxContext::frate
AVRational frate
Definition: cdxl.c:35
opt.h
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AV_OPT_TYPE_VIDEO_RATE
@ AV_OPT_TYPE_VIDEO_RATE
offset must point to AVRational
Definition: opt.h:258
cdxl_read_header
static int cdxl_read_header(AVFormatContext *s)
Definition: cdxl.c:103
AV_RN16
#define AV_RN16(p)
Definition: intreadwrite.h:354
CDXLDemuxContext::audio_stream_index
int audio_stream_index
Definition: cdxl.c:41
AVPacket::data
uint8_t * data
Definition: packet.h:520
AVOption
AVOption.
Definition: opt.h:357
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:538
AVCodecParameters::codec_tag
uint32_t codec_tag
Additional information about the codec (corresponds to the AVI FOURCC).
Definition: codec_par.h:59
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:454
avio_size
int64_t avio_size(AVIOContext *s)
Get the filesize.
Definition: aviobuf.c:323
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:575
sample_rate
sample_rate
Definition: ffmpeg_filter.c:424
CDXLDemuxContext::pos
int64_t pos
Definition: cdxl.c:43
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:853
av_shrink_packet
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: packet.c:113
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
type
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf type
Definition: writing_filters.txt:86
AVStream::duration
int64_t duration
Decoding: duration of the stream, in stream time base.
Definition: avformat.h:802
AVRational::num
int num
Numerator.
Definition: rational.h:59
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:42
width
#define width
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: packet.c:98
format
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 format(the sample packing is implied by the sample format) and sample rate. The lists are not just lists
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:134
CDXLDemuxContext::read_chunk
int read_chunk
Definition: cdxl.c:34
channels
channels
Definition: aptx.h:31
AVFormatContext
Format I/O context.
Definition: avformat.h:1255
CDXLDemuxContext::header
uint8_t header[CDXL_HEADER_SIZE]
Definition: cdxl.c:39
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
AVFMTCTX_NOHEADER
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:1206
AVRational
Rational number (pair of numerator and denominator).
Definition: rational.h:58
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
AV_RN32
#define AV_RN32(p)
Definition: intreadwrite.h:358
parseutils.h
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
CDXLDemuxContext::frame_rate
AVRational frame_rate
Definition: cdxl.c:37
cdxl_read_probe
static int cdxl_read_probe(const AVProbeData *p)
Definition: cdxl.c:46
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:461
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
AVStream::nb_frames
int64_t nb_frames
number of frames in this stream if known or 0
Definition: avformat.h:804
CDXL_HEADER_SIZE
#define CDXL_HEADER_SIZE
Definition: cdxl.c:30
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
read_seek
static int read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: cdxl.c:237
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:94
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
AV_RL24
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_RL24
Definition: bytestream.h:93
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
height
#define height
CDXLDemuxContext
Definition: cdxl.c:32
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:526
cdxl_demuxer_class
static const AVClass cdxl_demuxer_class
Definition: cdxl.c:254
av_channel_layout_default
void av_channel_layout_default(AVChannelLayout *ch_layout, int nb_channels)
Get the default channel layout for a given number of channels.
Definition: channel_layout.c:834
AVCodecParameters::height
int height
Definition: codec_par.h:135
demux.h
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:91
CDXLDemuxContext::srate
int srate
Definition: cdxl.c:36
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
cdxl_read_packet
static int cdxl_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: cdxl.c:118
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
OFFSET
#define OFFSET(x)
Definition: cdxl.c:247
CDXLDemuxContext::video_stream_index
int video_stream_index
Definition: cdxl.c:40
avformat.h
cdxl_options
static const AVOption cdxl_options[]
Definition: cdxl.c:248
AVStream::index
int index
stream index in AVFormatContext
Definition: avformat.h:749
ff_cdxl_demuxer
const FFInputFormat ff_cdxl_demuxer
Definition: cdxl.c:261
channel_layout.h
AVRational::den
int den
Denominator.
Definition: rational.h:60
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:245
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:612
CDXLDemuxContext::sample_rate
int sample_rate
Definition: cdxl.c:38
AVPacket::stream_index
int stream_index
Definition: packet.h:522
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:318
AV_OPT_FLAG_DECODING_PARAM
#define AV_OPT_FLAG_DECODING_PARAM
A generic parameter which can be set by the user for demuxing or decoding.
Definition: opt.h:284
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:78
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:497
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:540
FFInputFormat
Definition: demux.h:37
CDXLDemuxContext::filesize
int64_t filesize
Definition: cdxl.c:42
AV_CODEC_ID_PCM_S8_PLANAR
@ AV_CODEC_ID_PCM_S8_PLANAR
Definition: codec_id.h:355
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
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
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:792
AV_CODEC_ID_CDXL
@ AV_CODEC_ID_CDXL
Definition: codec_id.h:211
AV_RB16
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_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:98
avio_feof
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:346