libavformat/icodec.c

   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 "libavutil/mem.h"
  29 #include "libavcodec/bytestream.h"
  30 #include "libavcodec/png.h"
  31 #include "avformat.h"
  32 #include "demux.h"
  33 #include "internal.h"
  34
  35 typedef struct {
  36     int offset;
  37     int size;
  38     int nb_pal;
  39 } IcoImage;
  40
  41 typedef struct {
  42     int current_image;
  43     int nb_images;
  44     IcoImage * images;
  45 } IcoDemuxContext;
  46
  47 static int probe(const AVProbeData *p)
  48 {
  49     unsigned i, frames, checked = 0;
  50
  51     if (p->buf_size < 22 || AV_RL16(p->buf) || AV_RL16(p->buf + 2) != 1)
  52         return 0;
  53     frames = AV_RL16(p->buf + 4);
  54     if (!frames)
  55         return 0;
  56     for (i = 0; i < frames && i * 16 + 22 <= p->buf_size; i++) {
  57         unsigned offset;
  58         if (AV_RL16(p->buf + 10 + i * 16) & ~1)
  59             return FFMIN(i, AVPROBE_SCORE_MAX / 4);
  60         if (p->buf[13 + i * 16])
  61             return FFMIN(i, AVPROBE_SCORE_MAX / 4);
  62         if (AV_RL32(p->buf + 14 + i * 16) < 40)
  63             return FFMIN(i, AVPROBE_SCORE_MAX / 4);
  64         offset = AV_RL32(p->buf + 18 + i * 16);
  65         if (offset < 22)
  66             return FFMIN(i, AVPROBE_SCORE_MAX / 4);
  67         if (offset > p->buf_size - 8)
  68             continue;
  69         if (p->buf[offset] != 40 && AV_RB64(p->buf + offset) != PNGSIG)
  70             return FFMIN(i, AVPROBE_SCORE_MAX / 4);
  71         checked++;
  72     }
  73
  74     if (checked < frames)
  75         return AVPROBE_SCORE_MAX / 4 + FFMIN(checked, 1);
  76     return AVPROBE_SCORE_MAX / 2 + 1;
  77 }
  78
  79 static int read_header(AVFormatContext *s)
  80 {
  81     IcoDemuxContext *ico = s->priv_data;
  82     AVIOContext *pb = s->pb;
  83     int i, codec;
  84
  85     avio_skip(pb, 4);
  86     ico->nb_images = avio_rl16(pb);
  87
  88     if (!ico->nb_images)
  89         return AVERROR_INVALIDDATA;
  90
  91     ico->images = av_malloc_array(ico->nb_images, sizeof(IcoImage));
  92     if (!ico->images)
  93         return AVERROR(ENOMEM);
  94
  95     for (i = 0; i < ico->nb_images; i++) {
  96         AVStream *st;
  97         int tmp;
  98
  99         if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
 100             return AVERROR_INVALIDDATA;
 101
 102         st = avformat_new_stream(s, NULL);
 103         if (!st)
 104             return AVERROR(ENOMEM);
 105
 106         st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
 107         st->codecpar->width      = avio_r8(pb);
 108         st->codecpar->height     = avio_r8(pb);
 109         ico->images[i].nb_pal = avio_r8(pb);
 110         if (ico->images[i].nb_pal == 255)
 111             ico->images[i].nb_pal = 0;
 112
 113         avio_skip(pb, 5);
 114
 115         ico->images[i].size   = avio_rl32(pb);
 116         if (ico->images[i].size <= 0) {
 117             av_log(s, AV_LOG_ERROR, "Invalid image size %d\n", ico->images[i].size);
 118             return AVERROR_INVALIDDATA;
 119         }
 120         ico->images[i].offset = avio_rl32(pb);
 121
 122         if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0)
 123             return AVERROR_INVALIDDATA;
 124
 125         codec = avio_rl32(pb);
 126         switch (codec) {
 127         case MKTAG(0x89, 'P', 'N', 'G'):
 128             st->codecpar->codec_id = AV_CODEC_ID_PNG;
 129             st->codecpar->width    = 0;
 130             st->codecpar->height   = 0;
 131             break;
 132         case 40:
 133             if (ico->images[i].size < 40)
 134                 return AVERROR_INVALIDDATA;
 135             st->codecpar->codec_id = AV_CODEC_ID_BMP;
 136             tmp = avio_rl32(pb);
 137             if (tmp)
 138                 st->codecpar->width = tmp;
 139             tmp = avio_rl32(pb);
 140             if (tmp)
 141                 st->codecpar->height = tmp / 2;
 142             break;
 143         default:
 144             avpriv_request_sample(s, "codec %d", codec);
 145             return AVERROR_INVALIDDATA;
 146         }
 147     }
 148
 149     return 0;
 150 }
 151
 152 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 153 {
 154     IcoDemuxContext *ico = s->priv_data;
 155     IcoImage *image;
 156     AVIOContext *pb = s->pb;
 157     AVStream *st;
 158     int ret;
 159
 160     if (ico->current_image >= ico->nb_images)
 161         return AVERROR_EOF;
 162
 163     st = s->streams[0];
 164
 165     image = &ico->images[ico->current_image];
 166
 167     if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
 168         return ret;
 169
 170     if (s->streams[ico->current_image]->codecpar->codec_id == AV_CODEC_ID_PNG) {
 171         if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
 172             return ret;
 173     } else {
 174         uint8_t *buf;
 175         if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
 176             return ret;
 177         buf = pkt->data;
 178
 179         /* add BMP header */
 180         bytestream_put_byte(&buf, 'B');
 181         bytestream_put_byte(&buf, 'M');
 182         bytestream_put_le32(&buf, pkt->size);
 183         bytestream_put_le16(&buf, 0);
 184         bytestream_put_le16(&buf, 0);
 185         bytestream_put_le32(&buf, 0);
 186
 187         if ((ret = avio_read(pb, buf, image->size)) != image->size) {
 188             return ret < 0 ? ret : AVERROR_INVALIDDATA;
 189         }
 190
 191         st->codecpar->bits_per_coded_sample = AV_RL16(buf + 14);
 192
 193         if (AV_RL32(buf + 32))
 194             image->nb_pal = AV_RL32(buf + 32);
 195
 196         if (st->codecpar->bits_per_coded_sample <= 8 && !image->nb_pal) {
 197             image->nb_pal = 1 << st->codecpar->bits_per_coded_sample;
 198             AV_WL32(buf + 32, image->nb_pal);
 199         }
 200
 201         if (image->nb_pal > INT_MAX / 4 - 14 - 40U)
 202             return AVERROR_INVALIDDATA;
 203
 204         AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
 205         AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
 206     }
 207
 208     pkt->stream_index = ico->current_image++;
 209     pkt->flags |= AV_PKT_FLAG_KEY;
 210
 211     return 0;
 212 }
 213
 214 static int ico_read_close(AVFormatContext * s)
 215 {
 216     IcoDemuxContext *ico = s->priv_data;
 217     av_freep(&ico->images);
 218     return 0;
 219 }
 220
 221 const FFInputFormat ff_ico_demuxer = {
 222     .p.name         = "ico",
 223     .p.long_name    = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
 224     .p.flags        = AVFMT_NOTIMESTAMPS,
 225     .priv_data_size = sizeof(IcoDemuxContext),
 226     .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,
 227     .read_probe     = probe,
 228     .read_header    = read_header,
 229     .read_packet    = read_packet,
 230     .read_close     = ico_read_close,
 231 };