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 {
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;
160  int ret;
161 
162  if (ico->current_image >= ico->nb_images)
163  return AVERROR_EOF;
164 
165  st = s->streams[0];
166 
167  image = &ico->images[ico->current_image];
168 
169  if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
170  return ret;
171 
173  if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
174  return ret;
175  } else {
176  uint8_t *buf;
177  if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
178  return ret;
179  buf = pkt->data;
180 
181  /* add BMP header */
182  bytestream_put_byte(&buf, 'B');
183  bytestream_put_byte(&buf, 'M');
184  bytestream_put_le32(&buf, pkt->size);
185  bytestream_put_le16(&buf, 0);
186  bytestream_put_le16(&buf, 0);
187  bytestream_put_le32(&buf, 0);
188 
189  if ((ret = avio_read(pb, buf, image->size)) != image->size) {
190  return ret < 0 ? ret : AVERROR_INVALIDDATA;
191  }
192 
193  st->codecpar->bits_per_coded_sample = AV_RL16(buf + 14);
194 
195  if (AV_RL32(buf + 32))
196  image->nb_pal = AV_RL32(buf + 32);
197 
198  if (st->codecpar->bits_per_coded_sample <= 8 && !image->nb_pal) {
199  image->nb_pal = 1 << st->codecpar->bits_per_coded_sample;
200  AV_WL32(buf + 32, image->nb_pal);
201  }
202 
203  AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
204  AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
205  }
206 
207  pkt->stream_index = ico->current_image++;
208  pkt->flags |= AV_PKT_FLAG_KEY;
209 
210  return 0;
211 }
212 
214 {
215  IcoDemuxContext *ico = s->priv_data;
216  av_freep(&ico->images);
217  return 0;
218 }
219 
221  .name = "ico",
222  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
223  .priv_data_size = sizeof(IcoDemuxContext),
224  .read_probe = probe,
229 };
#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
#define avpriv_request_sample(...)
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int size
Definition: packet.h:364
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:341
static AVPacket pkt
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:91
if it could not because there are no more frames
int offset
Definition: icodec.c:35
IcoImage * images
Definition: icodec.c:43
Format I/O context.
Definition: avformat.h:1239
uint8_t
int width
Video only.
Definition: codec_par.h:126
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
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4453
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1307
uint8_t * data
Definition: packet.h:363
#define AVERROR_EOF
End of file.
Definition: error.h:55
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
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:305
#define av_log(a,...)
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:637
AVInputFormat ff_ico_demuxer
Definition: icodec.c:220
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:401
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
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
int nb_pal
Definition: icodec.c:37
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:752
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:153
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
#define PNGSIG
Definition: png.h:47
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:369
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:628
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
#define FFMIN(a, b)
Definition: common.h:96
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:880
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:462
AVIOContext * pb
I/O context.
Definition: avformat.h:1281
int current_image
Definition: icodec.c:41
static int ico_read_close(AVFormatContext *s)
Definition: icodec.c:213
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: icodec.c:154
#define flags(name, subs,...)
Definition: cbs_av1.c:560
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
static int probe(const AVProbeData *p)
Definition: icodec.c:46
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:736
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:91
Main libavformat public API header.
int size
Definition: icodec.c:36
int nb_images
Definition: icodec.c:42
void * priv_data
Format private data.
Definition: avformat.h:1267
int bits_per_coded_sample
The number of bits per sample in the codedwords.
Definition: codec_par.h:102
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:652
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1045
#define av_malloc_array(a, b)
static int read_header(AVFormatContext *s)
Definition: icodec.c:78
int stream_index
Definition: packet.h:365
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
#define MKTAG(a, b, c, d)
Definition: common.h:405
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:91
This structure stores compressed data.
Definition: packet.h:340
int i
Definition: input.c:407
#define AV_WL32(p, v)
Definition: intreadwrite.h:426
static uint8_t tmp[11]
Definition: aes_ctr.c:26