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/png.h"
30 #include "avformat.h"
31 #include "internal.h"
32 
33 typedef struct {
34  int offset;
35  int size;
36  int nb_pal;
37 } IcoImage;
38 
39 typedef struct {
40  int current_image;
41  int nb_images;
42  IcoImage * images;
43 } IcoDemuxContext;
44 
45 static int probe(const AVProbeData *p)
46 {
47  unsigned i, frames, checked = 0;
48 
49  if (p->buf_size < 22 || AV_RL16(p->buf) || AV_RL16(p->buf + 2) != 1)
50  return 0;
51  frames = AV_RL16(p->buf + 4);
52  if (!frames)
53  return 0;
54  for (i = 0; i < frames && i * 16 + 22 <= p->buf_size; i++) {
55  unsigned offset;
56  if (AV_RL16(p->buf + 10 + i * 16) & ~1)
57  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
58  if (p->buf[13 + i * 16])
59  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
60  if (AV_RL32(p->buf + 14 + i * 16) < 40)
61  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
62  offset = AV_RL32(p->buf + 18 + i * 16);
63  if (offset < 22)
64  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
65  if (offset > p->buf_size - 8)
66  continue;
67  if (p->buf[offset] != 40 && AV_RB64(p->buf + offset) != PNGSIG)
68  return FFMIN(i, AVPROBE_SCORE_MAX / 4);
69  checked++;
70  }
71 
72  if (checked < frames)
73  return AVPROBE_SCORE_MAX / 4 + FFMIN(checked, 1);
74  return AVPROBE_SCORE_MAX / 2 + 1;
75 }
76 
77 static int read_header(AVFormatContext *s)
78 {
79  IcoDemuxContext *ico = s->priv_data;
80  AVIOContext *pb = s->pb;
81  int i, codec;
82 
83  avio_skip(pb, 4);
84  ico->nb_images = avio_rl16(pb);
85 
86  if (!ico->nb_images)
87  return AVERROR_INVALIDDATA;
88 
89  ico->images = av_malloc_array(ico->nb_images, sizeof(IcoImage));
90  if (!ico->images)
91  return AVERROR(ENOMEM);
92 
93  for (i = 0; i < ico->nb_images; i++) {
94  AVStream *st;
95  int tmp;
96 
97  if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
98  return AVERROR_INVALIDDATA;
99 
100  st = avformat_new_stream(s, NULL);
101  if (!st)
102  return AVERROR(ENOMEM);
103 
104  st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
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  return AVERROR_INVALIDDATA;
117  }
118  ico->images[i].offset = avio_rl32(pb);
119 
120  if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0)
121  return AVERROR_INVALIDDATA;
122 
123  codec = avio_rl32(pb);
124  switch (codec) {
125  case MKTAG(0x89, 'P', 'N', 'G'):
126  st->codecpar->codec_id = AV_CODEC_ID_PNG;
127  st->codecpar->width = 0;
128  st->codecpar->height = 0;
129  break;
130  case 40:
131  if (ico->images[i].size < 40)
132  return AVERROR_INVALIDDATA;
133  st->codecpar->codec_id = AV_CODEC_ID_BMP;
134  tmp = avio_rl32(pb);
135  if (tmp)
136  st->codecpar->width = tmp;
137  tmp = avio_rl32(pb);
138  if (tmp)
139  st->codecpar->height = tmp / 2;
140  break;
141  default:
142  avpriv_request_sample(s, "codec %d", codec);
143  return AVERROR_INVALIDDATA;
144  }
145  }
146 
147  return 0;
148 }
149 
150 static int read_packet(AVFormatContext *s, AVPacket *pkt)
151 {
152  IcoDemuxContext *ico = s->priv_data;
153  IcoImage *image;
154  AVIOContext *pb = s->pb;
155  AVStream *st;
156  int ret;
157 
158  if (ico->current_image >= ico->nb_images)
159  return AVERROR_EOF;
160 
161  st = s->streams[0];
162 
163  image = &ico->images[ico->current_image];
164 
165  if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
166  return ret;
167 
168  if (s->streams[ico->current_image]->codecpar->codec_id == AV_CODEC_ID_PNG) {
169  if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
170  return ret;
171  } else {
172  uint8_t *buf;
173  if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
174  return ret;
175  buf = pkt->data;
176 
177  /* add BMP header */
178  bytestream_put_byte(&buf, 'B');
179  bytestream_put_byte(&buf, 'M');
180  bytestream_put_le32(&buf, pkt->size);
181  bytestream_put_le16(&buf, 0);
182  bytestream_put_le16(&buf, 0);
183  bytestream_put_le32(&buf, 0);
184 
185  if ((ret = avio_read(pb, buf, image->size)) != image->size) {
186  return ret < 0 ? ret : AVERROR_INVALIDDATA;
187  }
188 
189  st->codecpar->bits_per_coded_sample = AV_RL16(buf + 14);
190 
191  if (AV_RL32(buf + 32))
192  image->nb_pal = AV_RL32(buf + 32);
193 
194  if (st->codecpar->bits_per_coded_sample <= 8 && !image->nb_pal) {
195  image->nb_pal = 1 << st->codecpar->bits_per_coded_sample;
196  AV_WL32(buf + 32, image->nb_pal);
197  }
198 
199  if (image->nb_pal > INT_MAX / 4 - 14 - 40)
200  return AVERROR_INVALIDDATA;
201 
202  AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
203  AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
204  }
205 
206  pkt->stream_index = ico->current_image++;
207  pkt->flags |= AV_PKT_FLAG_KEY;
208 
209  return 0;
210 }
211 
212 static int ico_read_close(AVFormatContext * s)
213 {
214  IcoDemuxContext *ico = s->priv_data;
215  av_freep(&ico->images);
216  return 0;
217 }
218 
219 const AVInputFormat ff_ico_demuxer = {
220  .name = "ico",
221  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
222  .priv_data_size = sizeof(IcoDemuxContext),
223  .flags_internal = FF_FMT_INIT_CLEANUP,
224  .read_probe = probe,
225  .read_header = read_header,
226  .read_packet = read_packet,
227  .read_close = ico_read_close,
228  .flags = AVFMT_NOTIMESTAMPS,
229 };
IcoDemuxContext::nb_images
int nb_images
Definition: icodec.c:41
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:46
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AV_WL32
#define AV_WL32(p, v)
Definition: intreadwrite.h:424
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
AVFMT_NOTIMESTAMPS
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:480
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:28
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:455
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
read_header
static int read_header(AVFormatContext *s)
Definition: icodec.c:77
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:464
IcoDemuxContext::images
IcoImage * images
Definition: icodec.c:42
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:143
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:761
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:547
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
ico_read_close
static int ico_read_close(AVFormatContext *s)
Definition: icodec.c:212
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:98
AV_CODEC_ID_BMP
@ AV_CODEC_ID_BMP
Definition: codec_id.h:130
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:552
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:454
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
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:113
AVFormatContext
Format I/O context.
Definition: avformat.h:1105
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:862
NULL
#define NULL
Definition: coverity.c:32
ff_ico_demuxer
const AVInputFormat ff_ico_demuxer
Definition: icodec.c:219
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:452
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:777
AVIOContext
Bytestream IO Context.
Definition: avio.h:166
AVPacket::size
int size
Definition: packet.h:375
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:106
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:650
read_packet
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: icodec.c:150
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:380
PNGSIG
#define PNGSIG
Definition: png.h:49
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:244
AVCodecParameters::height
int height
Definition: codec_par.h:129
av_malloc_array
#define av_malloc_array(a, b)
Definition: tableprint_vlc.h:31
IcoImage
Definition: icodec.c:33
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:103
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:839
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:278
avformat.h
IcoImage::offset
int offset
Definition: icodec.c:34
IcoImage::size
int size
Definition: icodec.c:35
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:40
probe
static int probe(const AVProbeData *p)
Definition: icodec.c:45
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:659
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:365
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:29
AVCodecParameters::bits_per_coded_sample
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:104
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
png.h
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
bytestream.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:467
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
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
IcoDemuxContext
Definition: icodec.c:39
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:36
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