2 * Microsoft Windows ICO demuxer
3 * Copyright (c) 2011 Peter Ross (pross@xvid.org)
5 * This file is part of FFmpeg.
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.
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.
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
24 * Microsoft Windows ICO demuxer
27 #include "libavutil/intreadwrite.h"
28 #include "libavcodec/bytestream.h"
29 #include "libavcodec/bmp.h"
45 static int probe(AVProbeData *p)
47 if (AV_RL16(p->buf) == 0 && AV_RL16(p->buf + 2) == 1 && AV_RL16(p->buf + 4))
48 return AVPROBE_SCORE_MAX / 3;
52 static int read_header(AVFormatContext *s, AVFormatParameters *ap)
54 IcoDemuxContext *ico = s->priv_data;
55 AVIOContext *pb = s->pb;
59 ico->nb_images = avio_rl16(pb);
61 ico->images = av_malloc(ico->nb_images * sizeof(IcoImage));
63 return AVERROR(ENOMEM);
65 for (i = 0; i < ico->nb_images; i++) {
69 if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
72 st = avformat_new_stream(s, NULL);
74 return AVERROR(ENOMEM);
76 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
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;
85 ico->images[i].size = avio_rl32(pb);
86 ico->images[i].offset = avio_rl32(pb);
88 if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0)
91 switch(avio_rl32(pb)) {
92 case MKTAG(0x89, 'P', 'N', 'G'):
93 st->codec->codec_id = CODEC_ID_PNG;
95 st->codec->height = 0;
98 if (ico->images[i].size < 40)
99 return AVERROR_INVALIDDATA;
100 st->codec->codec_id = CODEC_ID_BMP;
103 st->codec->width = tmp;
106 st->codec->height = tmp / 2;
109 av_log_ask_for_sample(s, "unsupported codec\n");
110 return AVERROR_INVALIDDATA;
117 static int read_packet(AVFormatContext *s, AVPacket *pkt)
119 IcoDemuxContext *ico = s->priv_data;
121 AVIOContext *pb = s->pb;
122 AVStream *st = s->streams[0];
125 if (ico->current_image >= ico->nb_images)
128 image = &ico->images[ico->current_image];
130 if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
133 if (s->streams[ico->current_image]->codec->codec_id == CODEC_ID_PNG) {
134 if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
138 if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
143 bytestream_put_byte(&buf, 'B');
144 bytestream_put_byte(&buf, 'M');
145 bytestream_put_le32(&buf, pkt->size);
146 bytestream_put_le16(&buf, 0);
147 bytestream_put_le16(&buf, 0);
148 bytestream_put_le32(&buf, 0);
150 if ((ret = avio_read(pb, buf, image->size)) < 0)
153 st->codec->bits_per_coded_sample = AV_RL16(buf + 14);
155 if (AV_RL32(buf + 32))
156 image->nb_pal = AV_RL32(buf + 32);
158 if (st->codec->bits_per_coded_sample <= 8 && !image->nb_pal) {
159 image->nb_pal = 1 << st->codec->bits_per_coded_sample;
160 AV_WL32(buf + 32, image->nb_pal);
163 AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
164 AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
167 pkt->stream_index = ico->current_image++;
168 pkt->flags |= AV_PKT_FLAG_KEY;
173 AVInputFormat ff_ico_demuxer = {
175 .long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
176 .priv_data_size = sizeof(IcoDemuxContext),
178 .read_header = read_header,
179 .read_packet = read_packet,
180 .flags = AVFMT_NOTIMESTAMPS,