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 "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 {
  41     int current_image;
  42     int nb_images;
  43     IcoImage * images;
  44 } IcoDemuxContext;
  45
  46 static int probe(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
  78 static int read_header(AVFormatContext *s)
  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     if (!ico->nb_images)
  88         return AVERROR_INVALIDDATA;
  89
  90     ico->images = av_malloc_array(ico->nb_images, sizeof(IcoImage));
  91     if (!ico->images)
  92         return AVERROR(ENOMEM);
  93
  94     for (i = 0; i < ico->nb_images; i++) {
  95         AVStream *st;
  96         int tmp;
  97
  98         if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
  99             goto fail;
 100
 101         st = avformat_new_stream(s, NULL);
 102         if (!st) {
 103             av_freep(&ico->images);
 104             return AVERROR(ENOMEM);
 105         }
 106
 107         st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
 108         st->codecpar->width      = avio_r8(pb);
 109         st->codecpar->height     = avio_r8(pb);
 110         ico->images[i].nb_pal = avio_r8(pb);
 111         if (ico->images[i].nb_pal == 255)
 112             ico->images[i].nb_pal = 0;
 113
 114         avio_skip(pb, 5);
 115
 116         ico->images[i].size   = avio_rl32(pb);
 117         if (ico->images[i].size <= 0) {
 118             av_log(s, AV_LOG_ERROR, "Invalid image size %d\n", ico->images[i].size);
 119             goto fail;
 120         }
 121         ico->images[i].offset = avio_rl32(pb);
 122
 123         if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0)
 124             goto fail;
 125
 126         codec = avio_rl32(pb);
 127         switch (codec) {
 128         case MKTAG(0x89, 'P', 'N', 'G'):
 129             st->codecpar->codec_id = AV_CODEC_ID_PNG;
 130             st->codecpar->width    = 0;
 131             st->codecpar->height   = 0;
 132             break;
 133         case 40:
 134             if (ico->images[i].size < 40) {
 135                 goto fail;
 136             }
 137             st->codecpar->codec_id = AV_CODEC_ID_BMP;
 138             tmp = avio_rl32(pb);
 139             if (tmp)
 140                 st->codecpar->width = tmp;
 141             tmp = avio_rl32(pb);
 142             if (tmp)
 143                 st->codecpar->height = tmp / 2;
 144             break;
 145         default:
 146             avpriv_request_sample(s, "codec %d", codec);
 147             goto fail;
 148         }
 149     }
 150
 151     return 0;
 152 fail:
 153     av_freep(&ico->images);
 154     return AVERROR_INVALIDDATA;
 155 }
 156
 157 static int read_packet(AVFormatContext *s, AVPacket *pkt)
 158 {
 159     IcoDemuxContext *ico = s->priv_data;
 160     IcoImage *image;
 161     AVIOContext *pb = s->pb;
 162     AVStream *st;
 163     int ret;
 164
 165     if (ico->current_image >= ico->nb_images)
 166         return AVERROR_EOF;
 167
 168     st = s->streams[0];
 169
 170     image = &ico->images[ico->current_image];
 171
 172     if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
 173         return ret;
 174
 175     if (s->streams[ico->current_image]->codecpar->codec_id == AV_CODEC_ID_PNG) {
 176         if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
 177             return ret;
 178     } else {
 179         uint8_t *buf;
 180         if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
 181             return ret;
 182         buf = pkt->data;
 183
 184         /* add BMP header */
 185         bytestream_put_byte(&buf, 'B');
 186         bytestream_put_byte(&buf, 'M');
 187         bytestream_put_le32(&buf, pkt->size);
 188         bytestream_put_le16(&buf, 0);
 189         bytestream_put_le16(&buf, 0);
 190         bytestream_put_le32(&buf, 0);
 191
 192         if ((ret = avio_read(pb, buf, image->size)) != image->size) {
 193             av_packet_unref(pkt);
 194             return ret < 0 ? ret : AVERROR_INVALIDDATA;
 195         }
 196
 197         st->codecpar->bits_per_coded_sample = AV_RL16(buf + 14);
 198
 199         if (AV_RL32(buf + 32))
 200             image->nb_pal = AV_RL32(buf + 32);
 201
 202         if (st->codecpar->bits_per_coded_sample <= 8 && !image->nb_pal) {
 203             image->nb_pal = 1 << st->codecpar->bits_per_coded_sample;
 204             AV_WL32(buf + 32, image->nb_pal);
 205         }
 206
 207         if (image->nb_pal > INT_MAX / 4 - 14 - 40)
 208             return AVERROR_INVALIDDATA;
 209
 210         AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
 211         AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
 212     }
 213
 214     pkt->stream_index = ico->current_image++;
 215     pkt->flags |= AV_PKT_FLAG_KEY;
 216
 217     return 0;
 218 }
 219
 220 AVInputFormat ff_ico_demuxer = {
 221     .name           = "ico",
 222     .long_name      = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
 223     .priv_data_size = sizeof(IcoDemuxContext),
 224     .read_probe     = probe,
 225     .read_header    = read_header,
 226     .read_packet    = read_packet,
 227     .flags          = AVFMT_NOTIMESTAMPS,
 228 };