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 "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 {
41  int nb_images;
44 
45 static int probe(AVProbeData *p)
46 {
47  if (AV_RL16(p->buf) == 0 && AV_RL16(p->buf + 2) == 1 && AV_RL16(p->buf + 4))
48  return AVPROBE_SCORE_MAX / 3;
49  return 0;
50 }
51 
53 {
54  IcoDemuxContext *ico = s->priv_data;
55  AVIOContext *pb = s->pb;
56  int i, codec;
57 
58  avio_skip(pb, 4);
59  ico->nb_images = avio_rl16(pb);
60 
61  ico->images = av_malloc(ico->nb_images * sizeof(IcoImage));
62  if (!ico->images)
63  return AVERROR(ENOMEM);
64 
65  for (i = 0; i < ico->nb_images; i++) {
66  AVStream *st;
67  int tmp;
68 
69  if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
70  break;
71 
72  st = avformat_new_stream(s, NULL);
73  if (!st)
74  return AVERROR(ENOMEM);
75 
77  st->codec->width = avio_r8(pb);
78  st->codec->height = avio_r8(pb);
79  ico->images[i].nb_pal = avio_r8(pb);
80  if (ico->images[i].nb_pal == 255)
81  ico->images[i].nb_pal = 0;
82 
83  avio_skip(pb, 5);
84 
85  ico->images[i].size = avio_rl32(pb);
86  ico->images[i].offset = avio_rl32(pb);
87 
88  if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0)
89  break;
90 
91  codec = avio_rl32(pb);
92  switch (codec) {
93  case MKTAG(0x89, 'P', 'N', 'G'):
95  st->codec->width = 0;
96  st->codec->height = 0;
97  break;
98  case 40:
99  if (ico->images[i].size < 40)
100  return AVERROR_INVALIDDATA;
102  tmp = avio_rl32(pb);
103  if (tmp)
104  st->codec->width = tmp;
105  tmp = avio_rl32(pb);
106  if (tmp)
107  st->codec->height = tmp / 2;
108  break;
109  default:
110  avpriv_request_sample(s, "codec %d", codec);
111  return AVERROR_INVALIDDATA;
112  }
113  }
114 
115  return 0;
116 }
117 
119 {
120  IcoDemuxContext *ico = s->priv_data;
121  IcoImage *image;
122  AVIOContext *pb = s->pb;
123  AVStream *st = s->streams[0];
124  int ret;
125 
126  if (ico->current_image >= ico->nb_images)
127  return AVERROR(EIO);
128 
129  image = &ico->images[ico->current_image];
130 
131  if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
132  return ret;
133 
134  if (s->streams[ico->current_image]->codec->codec_id == AV_CODEC_ID_PNG) {
135  if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
136  return ret;
137  } else {
138  uint8_t *buf;
139  if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
140  return ret;
141  buf = pkt->data;
142 
143  /* add BMP header */
144  bytestream_put_byte(&buf, 'B');
145  bytestream_put_byte(&buf, 'M');
146  bytestream_put_le32(&buf, pkt->size);
147  bytestream_put_le16(&buf, 0);
148  bytestream_put_le16(&buf, 0);
149  bytestream_put_le32(&buf, 0);
150 
151  if ((ret = avio_read(pb, buf, image->size)) < 0)
152  return ret;
153 
154  st->codec->bits_per_coded_sample = AV_RL16(buf + 14);
155 
156  if (AV_RL32(buf + 32))
157  image->nb_pal = AV_RL32(buf + 32);
158 
159  if (st->codec->bits_per_coded_sample <= 8 && !image->nb_pal) {
160  image->nb_pal = 1 << st->codec->bits_per_coded_sample;
161  AV_WL32(buf + 32, image->nb_pal);
162  }
163 
164  AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
165  AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
166  }
167 
168  pkt->stream_index = ico->current_image++;
169  pkt->flags |= AV_PKT_FLAG_KEY;
170 
171  return 0;
172 }
173 
175  .name = "ico",
176  .long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
177  .priv_data_size = sizeof(IcoDemuxContext),
178  .read_probe = probe,
182 };
const char * s
Definition: avisynth_c.h:668
Bytestream IO Context.
Definition: avio.h:68
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:199
#define AV_RL16
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:256
int offset
Definition: icodec.c:34
IcoImage * images
Definition: icodec.c:42
Format I/O context.
Definition: avformat.h:944
#define AV_WL32(p, darg)
Definition: intreadwrite.h:282
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
uint8_t
static int probe(AVProbeData *p)
Definition: icodec.c:45
static AVPacket pkt
Definition: demuxing.c:56
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
AVStream ** streams
Definition: avformat.h:992
uint8_t * data
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.
int bits_per_coded_sample
bits per sample/pixel from the demuxer (needed for huffyuv).
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:478
AVInputFormat ff_ico_demuxer
Definition: icodec.c:174
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:73
int nb_pal
Definition: icodec.c:36
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:579
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
int flags
A combination of AV_PKT_FLAG values.
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:469
AVCodecContext * codec
Codec context associated with this stream.
Definition: avformat.h:662
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:336
static int read_probe(AVProbeData *pd)
ret
Definition: avfilter.c:821
int width
picture width / height.
#define AV_RL32
Stream structure.
Definition: avformat.h:643
#define AVFMT_NOTIMESTAMPS
Format does not need / have any timestamps.
Definition: avformat.h:352
NULL
Definition: eval.c:55
enum AVMediaType codec_type
enum AVCodecID codec_id
AVIOContext * pb
I/O context.
Definition: avformat.h:977
int current_image
Definition: icodec.c:40
void * buf
Definition: avisynth_c.h:594
void * av_malloc(size_t size)
Allocate a block of size bytes with alignment suitable for all memory accesses (including vectors if ...
Definition: mem.c:73
synthesis window for stochastic i
This structure contains the data a format has to probe a file.
Definition: avformat.h:334
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFilterBuffer 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.Buffer references ownership and permissions
static int read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: icodec.c:118
static int flags
Definition: cpu.c:23
#define AVPROBE_SCORE_MAX
maximum score, half of that is used for file-extension-based detection
Definition: avformat.h:340
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:563
Main libavformat public API header.
int size
Definition: icodec.c:35
int nb_images
Definition: icodec.c:41
void * priv_data
Format private data.
Definition: avformat.h:964
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:461
static int read_header(AVFormatContext *s)
Definition: icodec.c:52
#define MKTAG(a, b, c, d)
Definition: common.h:282
This structure stores compressed data.