FFmpeg  4.3
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 {
42  int nb_images;
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 
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  ico->images = av_malloc_array(ico->nb_images, sizeof(IcoImage));
88  if (!ico->images)
89  return AVERROR(ENOMEM);
90 
91  for (i = 0; i < ico->nb_images; i++) {
92  AVStream *st;
93  int tmp;
94 
95  if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
96  break;
97 
98  st = avformat_new_stream(s, NULL);
99  if (!st) {
100  av_freep(&ico->images);
101  return AVERROR(ENOMEM);
102  }
103 
105  st->codecpar->width = avio_r8(pb);
106  st->codecpar->height = avio_r8(pb);
107  ico->images[i].nb_pal = avio_r8(pb);
108  if (ico->images[i].nb_pal == 255)
109  ico->images[i].nb_pal = 0;
110 
111  avio_skip(pb, 5);
112 
113  ico->images[i].size = avio_rl32(pb);
114  if (ico->images[i].size <= 0) {
115  av_log(s, AV_LOG_ERROR, "Invalid image size %d\n", ico->images[i].size);
116  av_freep(&ico->images);
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  break;
123 
124  codec = avio_rl32(pb);
125  switch (codec) {
126  case MKTAG(0x89, 'P', 'N', 'G'):
128  st->codecpar->width = 0;
129  st->codecpar->height = 0;
130  break;
131  case 40:
132  if (ico->images[i].size < 40) {
133  av_freep(&ico->images);
134  return AVERROR_INVALIDDATA;
135  }
137  tmp = avio_rl32(pb);
138  if (tmp)
139  st->codecpar->width = tmp;
140  tmp = avio_rl32(pb);
141  if (tmp)
142  st->codecpar->height = tmp / 2;
143  break;
144  default:
145  avpriv_request_sample(s, "codec %d", codec);
146  av_freep(&ico->images);
147  return AVERROR_INVALIDDATA;
148  }
149  }
150 
151  return 0;
152 }
153 
155 {
156  IcoDemuxContext *ico = s->priv_data;
157  IcoImage *image;
158  AVIOContext *pb = s->pb;
159  AVStream *st = s->streams[0];
160  int ret;
161 
162  if (ico->current_image >= ico->nb_images)
163  return AVERROR_EOF;
164 
165  image = &ico->images[ico->current_image];
166 
167  if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
168  return ret;
169 
170  if (s->streams[ico->current_image]->codecpar->codec_id == AV_CODEC_ID_PNG) {
171  if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
172  return ret;
173  } else {
174  uint8_t *buf;
175  if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
176  return ret;
177  buf = pkt->data;
178 
179  /* add BMP header */
180  bytestream_put_byte(&buf, 'B');
181  bytestream_put_byte(&buf, 'M');
182  bytestream_put_le32(&buf, pkt->size);
183  bytestream_put_le16(&buf, 0);
184  bytestream_put_le16(&buf, 0);
185  bytestream_put_le32(&buf, 0);
186 
187  if ((ret = avio_read(pb, buf, image->size)) != image->size) {
188  return ret < 0 ? ret : AVERROR_INVALIDDATA;
189  }
190 
191  st->codecpar->bits_per_coded_sample = AV_RL16(buf + 14);
192 
193  if (AV_RL32(buf + 32))
194  image->nb_pal = AV_RL32(buf + 32);
195 
196  if (st->codecpar->bits_per_coded_sample <= 8 && !image->nb_pal) {
197  image->nb_pal = 1 << st->codecpar->bits_per_coded_sample;
198  AV_WL32(buf + 32, image->nb_pal);
199  }
200 
201  AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
202  AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
203  }
204 
205  pkt->stream_index = ico->current_image++;
207 
208  return 0;
209 }
210 
212 {
213  IcoDemuxContext *ico = s->priv_data;
214  av_freep(&ico->images);
215  return 0;
216 }
217 
219  .name = "ico",
220  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
221  .priv_data_size = sizeof(IcoDemuxContext),
222  .read_probe = probe,
227 };
IcoDemuxContext::nb_images
int nb_images
Definition: icodec.c:42
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:4519
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:55
MKTAG
#define MKTAG(a, b, c, d)
Definition: common.h:406
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:462
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:26
AVPacket::data
uint8_t * data
Definition: packet.h:355
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:388
read_header
static int read_header(AVFormatContext *s)
Definition: icodec.c:78
ff_ico_demuxer
AVInputFormat ff_ico_demuxer
Definition: icodec.c:218
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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:145
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:731
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
AVInputFormat
Definition: avformat.h:636
AV_RB64
#define AV_RB64
Definition: intreadwrite.h:164
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:211
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:88
AV_CODEC_ID_BMP
@ AV_CODEC_ID_BMP
Definition: codec_id.h:127
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:641
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:126
AV_RL16
#define AV_RL16
Definition: intreadwrite.h:42
AV_CODEC_ID_PNG
@ AV_CODEC_ID_PNG
Definition: codec_id.h:110
AVFormatContext
Format I/O context.
Definition: avformat.h:1335
internal.h
bmp.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1012
NULL
#define NULL
Definition: coverity.c:32
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:441
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:747
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
AVPacket::size
int size
Definition: packet.h:356
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:186
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:616
FFMIN
#define FFMIN(a, b)
Definition: common.h:96
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: icodec.c:154
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:361
PNGSIG
#define PNGSIG
Definition: png.h:47
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
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
uint8_t
uint8_t
Definition: audio_convert.c:194
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:304
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:865
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:241
avformat.h
IcoImage::offset
int offset
Definition: icodec.c:35
IcoImage::size
int size
Definition: icodec.c:36
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
AV_RL32
#define AV_RL32
Definition: intreadwrite.h:146
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:625
AVPacket::stream_index
int stream_index
Definition: packet.h:357
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:329
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:39
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:332
png.h
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:35
bytestream.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:564
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:59
IcoDemuxContext
Definition: icodec.c:40
IcoImage::nb_pal
int nb_pal
Definition: icodec.c:37