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
33typedef struct {
34    int offset;
35    int size;
36    int nb_pal;
37} IcoImage;
38
39typedef struct {
40    int current_image;
41    int nb_images;
42    IcoImage * images;
43} IcoDemuxContext;
44
45static 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 / 4;
49    return 0;
50}
51
52static int read_header(AVFormatContext *s)
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_array(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
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;
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'):
94            st->codec->codec_id = AV_CODEC_ID_PNG;
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;
101            st->codec->codec_id = AV_CODEC_ID_BMP;
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
118static int read_packet(AVFormatContext *s, AVPacket *pkt)
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
174AVInputFormat ff_ico_demuxer = {
175    .name           = "ico",
176    .long_name      = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
177    .priv_data_size = sizeof(IcoDemuxContext),
178    .read_probe     = probe,
179    .read_header    = read_header,
180    .read_packet    = read_packet,
181    .flags          = AVFMT_NOTIMESTAMPS,
182};
183