yading@11: /*
yading@11:  * Microsoft Windows ICO demuxer
yading@11:  * Copyright (c) 2011 Peter Ross (pross@xvid.org)
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * Microsoft Windows ICO demuxer
yading@11:  */
yading@11: 
yading@11: #include "libavutil/intreadwrite.h"
yading@11: #include "libavcodec/bytestream.h"
yading@11: #include "libavcodec/bmp.h"
yading@11: #include "avformat.h"
yading@11: #include "internal.h"
yading@11: 
yading@11: typedef struct {
yading@11:     int offset;
yading@11:     int size;
yading@11:     int nb_pal;
yading@11: } IcoImage;
yading@11: 
yading@11: typedef struct {
yading@11:     int current_image;
yading@11:     int nb_images;
yading@11:     IcoImage * images;
yading@11: } IcoDemuxContext;
yading@11: 
yading@11: static int probe(AVProbeData *p)
yading@11: {
yading@11:     if (AV_RL16(p->buf) == 0 && AV_RL16(p->buf + 2) == 1 && AV_RL16(p->buf + 4))
yading@11:         return AVPROBE_SCORE_MAX / 3;
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int read_header(AVFormatContext *s)
yading@11: {
yading@11:     IcoDemuxContext *ico = s->priv_data;
yading@11:     AVIOContext *pb = s->pb;
yading@11:     int i, codec;
yading@11: 
yading@11:     avio_skip(pb, 4);
yading@11:     ico->nb_images = avio_rl16(pb);
yading@11: 
yading@11:     ico->images = av_malloc(ico->nb_images * sizeof(IcoImage));
yading@11:     if (!ico->images)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     for (i = 0; i < ico->nb_images; i++) {
yading@11:         AVStream *st;
yading@11:         int tmp;
yading@11: 
yading@11:         if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0)
yading@11:             break;
yading@11: 
yading@11:         st = avformat_new_stream(s, NULL);
yading@11:         if (!st)
yading@11:             return AVERROR(ENOMEM);
yading@11: 
yading@11:         st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
yading@11:         st->codec->width      = avio_r8(pb);
yading@11:         st->codec->height     = avio_r8(pb);
yading@11:         ico->images[i].nb_pal = avio_r8(pb);
yading@11:         if (ico->images[i].nb_pal == 255)
yading@11:             ico->images[i].nb_pal = 0;
yading@11: 
yading@11:         avio_skip(pb, 5);
yading@11: 
yading@11:         ico->images[i].size   = avio_rl32(pb);
yading@11:         ico->images[i].offset = avio_rl32(pb);
yading@11: 
yading@11:         if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0)
yading@11:             break;
yading@11: 
yading@11:         codec = avio_rl32(pb);
yading@11:         switch (codec) {
yading@11:         case MKTAG(0x89, 'P', 'N', 'G'):
yading@11:             st->codec->codec_id = AV_CODEC_ID_PNG;
yading@11:             st->codec->width    = 0;
yading@11:             st->codec->height   = 0;
yading@11:             break;
yading@11:         case 40:
yading@11:             if (ico->images[i].size < 40)
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             st->codec->codec_id = AV_CODEC_ID_BMP;
yading@11:             tmp = avio_rl32(pb);
yading@11:             if (tmp)
yading@11:                 st->codec->width = tmp;
yading@11:             tmp = avio_rl32(pb);
yading@11:             if (tmp)
yading@11:                 st->codec->height = tmp / 2;
yading@11:             break;
yading@11:         default:
yading@11:             avpriv_request_sample(s, "codec %d", codec);
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int read_packet(AVFormatContext *s, AVPacket *pkt)
yading@11: {
yading@11:     IcoDemuxContext *ico = s->priv_data;
yading@11:     IcoImage *image;
yading@11:     AVIOContext *pb = s->pb;
yading@11:     AVStream *st = s->streams[0];
yading@11:     int ret;
yading@11: 
yading@11:     if (ico->current_image >= ico->nb_images)
yading@11:         return AVERROR(EIO);
yading@11: 
yading@11:     image = &ico->images[ico->current_image];
yading@11: 
yading@11:     if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0)
yading@11:         return ret;
yading@11: 
yading@11:     if (s->streams[ico->current_image]->codec->codec_id == AV_CODEC_ID_PNG) {
yading@11:         if ((ret = av_get_packet(pb, pkt, image->size)) < 0)
yading@11:             return ret;
yading@11:     } else {
yading@11:         uint8_t *buf;
yading@11:         if ((ret = av_new_packet(pkt, 14 + image->size)) < 0)
yading@11:             return ret;
yading@11:         buf = pkt->data;
yading@11: 
yading@11:         /* add BMP header */
yading@11:         bytestream_put_byte(&buf, 'B');
yading@11:         bytestream_put_byte(&buf, 'M');
yading@11:         bytestream_put_le32(&buf, pkt->size);
yading@11:         bytestream_put_le16(&buf, 0);
yading@11:         bytestream_put_le16(&buf, 0);
yading@11:         bytestream_put_le32(&buf, 0);
yading@11: 
yading@11:         if ((ret = avio_read(pb, buf, image->size)) < 0)
yading@11:             return ret;
yading@11: 
yading@11:         st->codec->bits_per_coded_sample = AV_RL16(buf + 14);
yading@11: 
yading@11:         if (AV_RL32(buf + 32))
yading@11:             image->nb_pal = AV_RL32(buf + 32);
yading@11: 
yading@11:         if (st->codec->bits_per_coded_sample <= 8 && !image->nb_pal) {
yading@11:             image->nb_pal = 1 << st->codec->bits_per_coded_sample;
yading@11:             AV_WL32(buf + 32, image->nb_pal);
yading@11:         }
yading@11: 
yading@11:         AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4);
yading@11:         AV_WL32(buf + 8, AV_RL32(buf + 8) / 2);
yading@11:     }
yading@11: 
yading@11:     pkt->stream_index = ico->current_image++;
yading@11:     pkt->flags |= AV_PKT_FLAG_KEY;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVInputFormat ff_ico_demuxer = {
yading@11:     .name           = "ico",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
yading@11:     .priv_data_size = sizeof(IcoDemuxContext),
yading@11:     .read_probe     = probe,
yading@11:     .read_header    = read_header,
yading@11:     .read_packet    = read_packet,
yading@11:     .flags          = AVFMT_NOTIMESTAMPS,
yading@11: };