FFmpeg
icodec.c
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1 /*
2  * Microsoft Windows ICO demuxer
3  * Copyright (c) 2011 Peter Ross (pross@xvid.org)
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  * @file
24  * Microsoft Windows ICO demuxer
25  */
26 
27 #include "libavutil/intreadwrite.h"
28 #include "libavcodec/bytestream.h"
29 #include "libavcodec/bmp.h"
30 #include "libavcodec/png.h"
31 #include "avformat.h"
32 #include "internal.h"
33 
34 typedef struct {
35  int offset;
36  int size;
37  int nb_pal;
38 } IcoImage;
39 
40 typedef struct {
41  int current_image;
42  int nb_images;
43  IcoImage * images;
44 } IcoDemuxContext;
45 
46 static int probe(const AVProbeData *p)
47 {
48  unsigned i, frames, checked = 0;
49 
50  if (p->buf_size < 22 || AV_RL16(p->buf) || AV_RL16(p->buf + 2) != 1)
51  return 0;
52  frames = AV_RL16(p->buf + 4);
53  if (!frames)
54  return 0;
55  for (i = 0; i < frames && i * 16 + 22 <= p->buf_size; i++) {
56  unsigned offset;
57  if (AV_RL16(p->buf + 10 + i * 16) & ~1)
58  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
59  if (p->buf[13 + i * 16])
60  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
61  if (AV_RL32(p->buf + 14 + i * 16) < 40)
62  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
63  offset = AV_RL32(p->buf + 18 + i * 16);
64  if (offset < 22)
65  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
66  if (offset > p->buf_size - 8)
67  continue;
68  if (p->buf[offset] != 40 && AV_RB64(p->buf + offset) != PNGSIG)
69  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
70  checked++;
71  }
72 
73  if (checked < frames)
74  return AVPROBE_SCORE_MAX / 4 + FFMIN(checked, 1);
75  return AVPROBE_SCORE_MAX / 2 + 1;
76 }
77 
78 static int read_header(AVFormatContext *s)
79 {
80  IcoDemuxContext *ico = s->priv_data;
81  AVIOContext *pb = s->pb;
82  int i, codec;
83 
84  avio_skip(pb, 4);
85  ico->nb_images = avio_rl16(pb);
86 
87  if (!ico->nb_images)
88  return AVERROR_INVALIDDATA;
89 
90  ico->images = av_malloc_array(ico->nb_images, sizeof(IcoImage));
91  if (!ico->images)
92  return AVERROR(ENOMEM);
93 
94  for (i = 0; i < ico->nb_images; i++) {
95  AVStream *st;
96  int tmp;
97 
98  if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
99  return AVERROR_INVALIDDATA;
100 
101  st = avformat_new_stream(s, NULL);
102  if (!st)
103  return AVERROR(ENOMEM);
104 
105  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
106  st->codecpar->width = avio_r8(pb);
107  st->codecpar->height = avio_r8(pb);
108  ico->images[i].nb_pal = avio_r8(pb);
109  if (ico->images[i].nb_pal == 255)
110  ico->images[i].nb_pal = 0;
111 
112  avio_skip(pb, 5);
113 
114  ico->images[i].size = avio_rl32(pb);
115  if (ico->images[i].size <= 0) {
116  av_log(s, AV_LOG_ERROR, "Invalid image size %d\n", ico->images[i].size);
117  return AVERROR_INVALIDDATA;
118  }
119  ico->images[i].offset = avio_rl32(pb);
120 
121  if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0)
122  return AVERROR_INVALIDDATA;
123 
124  codec = avio_rl32(pb);
125  switch (codec) {
126  case MKTAG(0x89, 'P', 'N', 'G'):
127  st->codecpar->codec_id = AV_CODEC_ID_PNG;
128  st->codecpar->width = 0;
129  st->codecpar->height = 0;
130  break;
131  case 40:
132  if (ico->images[i].size < 40)
133  return AVERROR_INVALIDDATA;
134  st->codecpar->codec_id = AV_CODEC_ID_BMP;
135  tmp = avio_rl32(pb);
136  if (tmp)
137  st->codecpar->width = tmp;
138  tmp = avio_rl32(pb);
139  if (tmp)
140  st->codecpar->height = tmp / 2;
141  break;
142  default:
143  avpriv_request_sample(s, "codec %d", codec);
144  return AVERROR_INVALIDDATA;
145  }
146  }
147 
148  return 0;
149 }
150 
151 static int read_packet(AVFormatContext *s, AVPacket *pkt)
152 {
153  IcoDemuxContext *ico = s->priv_data;
154  IcoImage *image;
155  AVIOContext *pb = s->pb;
156  AVStream *st;
157  int ret;
158 
159  if (ico->current_image >= ico->nb_images)
160  return AVERROR_EOF;
161 
162  st = s->streams[0];
163 
164  image = &ico->images[ico->current_image];
165 
166  if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
167  return ret;
168 
169  if (s->streams[ico->current_image]->codecpar->codec_id == AV_CODEC_ID_PNG) {
170  if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
171  return ret;
172  } else {
173  uint8_t *buf;
174  if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
175  return ret;
176  buf = pkt->data;
177 
178  /* add BMP header */
179  bytestream_put_byte(&buf, 'B');
180  bytestream_put_byte(&buf, 'M');
181  bytestream_put_le32(&buf, pkt->size);
182  bytestream_put_le16(&buf, 0);
183  bytestream_put_le16(&buf, 0);
184  bytestream_put_le32(&buf, 0);
185 
186  if ((ret = avio_read(pb, buf, image->size)) != image->size) {
187  return ret < 0 ? ret : AVERROR_INVALIDDATA;
188  }
189 
190  st->codecpar->bits_per_coded_sample = AV_RL16(buf + 14);
191 
192  if (AV_RL32(buf + 32))
193  image->nb_pal = AV_RL32(buf + 32);
194 
195  if (st->codecpar->bits_per_coded_sample <= 8 && !image->nb_pal) {
196  image->nb_pal = 1 << st->codecpar->bits_per_coded_sample;
197  AV_WL32(buf + 32, image->nb_pal);
198  }
199 
200  AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
201  AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
202  }
203 
204  pkt->stream_index = ico->current_image++;
205  pkt->flags |= AV_PKT_FLAG_KEY;
206 
207  return 0;
208 }
209 
210 static int ico_read_close(AVFormatContext * s)
211 {
212  IcoDemuxContext *ico = s->priv_data;
213  av_freep(&ico->images);
214  return 0;
215 }
216 
217 const AVInputFormat ff_ico_demuxer = {
218  .name = "ico",
219  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
220  .priv_data_size = sizeof(IcoDemuxContext),
221  .flags_internal = FF_FMT_INIT_CLEANUP,
222  .read_probe = probe,
223  .read_header = read_header,
224  .read_packet = read_packet,
225  .read_close = ico_read_close,
226  .flags = AVFMT_NOTIMESTAMPS,
227 };
IcoDemuxContext::nb_images
int nb_images
Definition: icodec.c:42
FF_FMT_INIT_CLEANUP
#define FF_FMT_INIT_CLEANUP
For an AVInputFormat with this flag set read_close() needs to be called by the caller upon read_heade...
Definition: internal.h:48
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: utils.c:760
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
AV_WL32
#define AV_WL32(p, v)
Definition: intreadwrite.h:426
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:468
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:26
AVPacket::data
uint8_t * data
Definition: packet.h:373
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:450
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:425
read_header
static int read_header(AVFormatContext *s)
Definition: icodec.c:78
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:459
IcoDemuxContext::images
IcoImage * images
Definition: icodec.c:43
frames
if it could not because there are no more frames
Definition: filter_design.txt:266
read_close
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:141
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:743
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:643
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
ico_read_close
static int ico_read_close(AVFormatContext *s)
Definition: icodec.c:210
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: avpacket.c:99
AV_CODEC_ID_BMP
@ AV_CODEC_ID_BMP
Definition: codec_id.h:128
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:648
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:449
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
AV_CODEC_ID_PNG
@ AV_CODEC_ID_PNG
Definition: codec_id.h:111
AVFormatContext
Format I/O context.
Definition: avformat.h:1193
internal.h
bmp.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1088
NULL
#define NULL
Definition: coverity.c:32
ff_ico_demuxer
const AVInputFormat ff_ico_demuxer
Definition: icodec.c:217
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:447
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:759
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
AVPacket::size
int size
Definition: packet.h:374
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
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:632
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: icodec.c:151
offset
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 offset
Definition: writing_filters.txt:86
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:379
PNGSIG
#define PNGSIG
Definition: png.h:49
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
AVCodecParameters::height
int height
Definition: codec_par.h:127
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:32
IcoImage
Definition: icodec.c:34
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
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:197
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:928
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
avformat.h
IcoImage::offset
int offset
Definition: icodec.c:35
IcoImage::size
int size
Definition: icodec.c:36
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
IcoDemuxContext::current_image
int current_image
Definition: icodec.c:41
probe
static int probe(const AVProbeData *p)
Definition: icodec.c:46
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:641
AVPacket::stream_index
int stream_index
Definition: packet.h:375
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
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:102
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
png.h
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
bytestream.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
IcoDemuxContext
Definition: icodec.c:40
AV_RB64
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_RB64
Definition: bytestream.h:95
IcoImage::nb_pal
int nb_pal
Definition: icodec.c:37
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