/* * Microsoft Windows ICO demuxer * Copyright (c) 2011 Peter Ross (pross@xvid.org) * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Microsoft Windows ICO demuxer */ #include "libavutil/intreadwrite.h" #include "libavcodec/bytestream.h" #include "libavcodec/png.h" #include "avformat.h" #include "demux.h" #include "internal.h" typedef struct { int offset; int size; int nb_pal; } IcoImage; typedef struct { int current_image; int nb_images; IcoImage * images; } IcoDemuxContext; static int probe(const AVProbeData *p) { unsigned i, frames, checked = 0; if (p->buf_size < 22 || AV_RL16(p->buf) || AV_RL16(p->buf + 2) != 1) return 0; frames = AV_RL16(p->buf + 4); if (!frames) return 0; for (i = 0; i < frames && i * 16 + 22 <= p->buf_size; i++) { unsigned offset; if (AV_RL16(p->buf + 10 + i * 16) & ~1) return FFMIN(i, AVPROBE_SCORE_MAX / 4); if (p->buf[13 + i * 16]) return FFMIN(i, AVPROBE_SCORE_MAX / 4); if (AV_RL32(p->buf + 14 + i * 16) < 40) return FFMIN(i, AVPROBE_SCORE_MAX / 4); offset = AV_RL32(p->buf + 18 + i * 16); if (offset < 22) return FFMIN(i, AVPROBE_SCORE_MAX / 4); if (offset > p->buf_size - 8) continue; if (p->buf[offset] != 40 && AV_RB64(p->buf + offset) != PNGSIG) return FFMIN(i, AVPROBE_SCORE_MAX / 4); checked++; } if (checked < frames) return AVPROBE_SCORE_MAX / 4 + FFMIN(checked, 1); return AVPROBE_SCORE_MAX / 2 + 1; } static int read_header(AVFormatContext *s) { IcoDemuxContext *ico = s->priv_data; AVIOContext *pb = s->pb; int i, codec; avio_skip(pb, 4); ico->nb_images = avio_rl16(pb); if (!ico->nb_images) return AVERROR_INVALIDDATA; ico->images = av_malloc_array(ico->nb_images, sizeof(IcoImage)); if (!ico->images) return AVERROR(ENOMEM); for (i = 0; i < ico->nb_images; i++) { AVStream *st; int tmp; if (avio_seek(pb, 6 + i * 16, SEEK_SET) < 0) return AVERROR_INVALIDDATA; st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; st->codecpar->width = avio_r8(pb); st->codecpar->height = avio_r8(pb); ico->images[i].nb_pal = avio_r8(pb); if (ico->images[i].nb_pal == 255) ico->images[i].nb_pal = 0; avio_skip(pb, 5); ico->images[i].size = avio_rl32(pb); if (ico->images[i].size <= 0) { av_log(s, AV_LOG_ERROR, "Invalid image size %d\n", ico->images[i].size); return AVERROR_INVALIDDATA; } ico->images[i].offset = avio_rl32(pb); if (avio_seek(pb, ico->images[i].offset, SEEK_SET) < 0) return AVERROR_INVALIDDATA; codec = avio_rl32(pb); switch (codec) { case MKTAG(0x89, 'P', 'N', 'G'): st->codecpar->codec_id = AV_CODEC_ID_PNG; st->codecpar->width = 0; st->codecpar->height = 0; break; case 40: if (ico->images[i].size < 40) return AVERROR_INVALIDDATA; st->codecpar->codec_id = AV_CODEC_ID_BMP; tmp = avio_rl32(pb); if (tmp) st->codecpar->width = tmp; tmp = avio_rl32(pb); if (tmp) st->codecpar->height = tmp / 2; break; default: avpriv_request_sample(s, "codec %d", codec); return AVERROR_INVALIDDATA; } } return 0; } static int read_packet(AVFormatContext *s, AVPacket *pkt) { IcoDemuxContext *ico = s->priv_data; IcoImage *image; AVIOContext *pb = s->pb; AVStream *st; int ret; if (ico->current_image >= ico->nb_images) return AVERROR_EOF; st = s->streams[0]; image = &ico->images[ico->current_image]; if ((ret = avio_seek(pb, image->offset, SEEK_SET)) < 0) return ret; if (s->streams[ico->current_image]->codecpar->codec_id == AV_CODEC_ID_PNG) { if ((ret = av_get_packet(pb, pkt, image->size)) < 0) return ret; } else { uint8_t *buf; if ((ret = av_new_packet(pkt, 14 + image->size)) < 0) return ret; buf = pkt->data; /* add BMP header */ bytestream_put_byte(&buf, 'B'); bytestream_put_byte(&buf, 'M'); bytestream_put_le32(&buf, pkt->size); bytestream_put_le16(&buf, 0); bytestream_put_le16(&buf, 0); bytestream_put_le32(&buf, 0); if ((ret = avio_read(pb, buf, image->size)) != image->size) { return ret < 0 ? ret : AVERROR_INVALIDDATA; } st->codecpar->bits_per_coded_sample = AV_RL16(buf + 14); if (AV_RL32(buf + 32)) image->nb_pal = AV_RL32(buf + 32); if (st->codecpar->bits_per_coded_sample <= 8 && !image->nb_pal) { image->nb_pal = 1 << st->codecpar->bits_per_coded_sample; AV_WL32(buf + 32, image->nb_pal); } if (image->nb_pal > INT_MAX / 4 - 14 - 40) return AVERROR_INVALIDDATA; AV_WL32(buf - 4, 14 + 40 + image->nb_pal * 4); AV_WL32(buf + 8, AV_RL32(buf + 8) / 2); } pkt->stream_index = ico->current_image++; pkt->flags |= AV_PKT_FLAG_KEY; return 0; } static int ico_read_close(AVFormatContext * s) { IcoDemuxContext *ico = s->priv_data; av_freep(&ico->images); return 0; } const FFInputFormat ff_ico_demuxer = { .p.name = "ico", .p.long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"), .p.flags = AVFMT_NOTIMESTAMPS, .priv_data_size = sizeof(IcoDemuxContext), .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP, .read_probe = probe, .read_header = read_header, .read_packet = read_packet, .read_close = ico_read_close, };