/*
* Microsoft Windows ICO muxer
* Copyright (c) 2012 Michael Bradshaw <mjbshaw gmail com>
*
* 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 muxer
*/
#include "libavutil/intreadwrite.h"
#include "libavutil/pixdesc.h"
#include "avformat.h"
typedef struct {
int offset;
int size;
unsigned char width;
unsigned char height;
short bits;
} IcoImage;
typedef struct {
int current_image;
int nb_images;
IcoImage *images;
} IcoMuxContext;
static int ico_check_attributes(AVFormatContext *s, const AVCodecContext *c)
{
if (c->codec_id == AV_CODEC_ID_BMP) {
if (c->pix_fmt == AV_PIX_FMT_PAL8 && AV_PIX_FMT_RGB32 != AV_PIX_FMT_BGRA) {
av_log(s, AV_LOG_ERROR, "Wrong endianness for bmp pixel format\n");
return AVERROR(EINVAL);
} else if (c->pix_fmt != AV_PIX_FMT_PAL8 &&
c->pix_fmt != AV_PIX_FMT_RGB555LE &&
c->pix_fmt != AV_PIX_FMT_BGR24 &&
c->pix_fmt != AV_PIX_FMT_BGRA) {
av_log(s, AV_LOG_ERROR, "BMP must be 1bit, 4bit, 8bit, 16bit, 24bit, or 32bit\n");
return AVERROR(EINVAL);
}
} else if (c->codec_id == AV_CODEC_ID_PNG) {
if (c->pix_fmt != AV_PIX_FMT_RGBA) {
av_log(s, AV_LOG_ERROR, "PNG in ico requires pixel format to be rgba\n");
return AVERROR(EINVAL);
}
} else {
const AVCodecDescriptor *codesc = avcodec_descriptor_get(c->codec_id);
av_log(s, AV_LOG_ERROR, "Unsupported codec %s\n", codesc ? codesc->name : "");
return AVERROR(EINVAL);
}
if (c->width > 256 ||
c->height > 256) {
av_log(s, AV_LOG_ERROR, "Unsupported dimensions %dx%d (dimensions cannot exceed 256x256)\n", c->width, c->height);
return AVERROR(EINVAL);
}
return 0;
}
static int ico_write_header(AVFormatContext *s)
{
IcoMuxContext *ico = s->priv_data;
AVIOContext *pb = s->pb;
int ret;
int i;
if (!pb->seekable) {
av_log(s, AV_LOG_ERROR, "Output is not seekable\n");
return AVERROR(EINVAL);
}
ico->current_image = 0;
ico->nb_images = s->nb_streams;
avio_wl16(pb, 0); // reserved
avio_wl16(pb, 1); // 1 == icon
avio_skip(pb, 2); // skip the number of images
for (i = 0; i < s->nb_streams; i++) {
if (ret = ico_check_attributes(s, s->streams[i]->codec))
return ret;
// Fill in later when writing trailer...
avio_skip(pb, 16);
}
ico->images = av_mallocz_array(ico->nb_images, sizeof(IcoMuxContext));
if (!ico->images)
return AVERROR(ENOMEM);
avio_flush(pb);
return 0;
}
static int ico_write_packet(AVFormatContext *s, AVPacket *pkt)
{
IcoMuxContext *ico = s->priv_data;
IcoImage *image;
AVIOContext *pb = s->pb;
AVCodecContext *c = s->streams[pkt->stream_index]->codec;
int i;
if (ico->current_image >= ico->nb_images) {
av_log(s, AV_LOG_ERROR, "ICO already contains %d images\n", ico->current_image);
return AVERROR(EIO);
}
image = &ico->images[ico->current_image++];
image->offset = avio_tell(pb);
image->width = (c->width == 256) ? 0 : c->width;
image->height = (c->height == 256) ? 0 : c->height;
if (c->codec_id == AV_CODEC_ID_PNG) {
image->bits = c->bits_per_coded_sample;
image->size = pkt->size;
avio_write(pb, pkt->data, pkt->size);
} else { // BMP
if (AV_RL32(pkt->data + 14) != 40) { // must be BITMAPINFOHEADER
av_log(s, AV_LOG_ERROR, "Invalid BMP\n");
return AVERROR(EINVAL);
}
image->bits = AV_RL16(pkt->data + 28); // allows things like 1bit and 4bit images to be preserved
image->size = pkt->size - 14 + c->height * (c->width + 7) / 8;
avio_write(pb, pkt->data + 14, 8); // Skip the BITMAPFILEHEADER header
avio_wl32(pb, AV_RL32(pkt->data + 22) * 2); // rewrite height as 2 * height
avio_write(pb, pkt->data + 26, pkt->size - 26);
for (i = 0; i < c->height * (c->width + 7) / 8; ++i)
avio_w8(pb, 0x00); // Write bitmask (opaque)
}
return 0;
}
static int ico_write_trailer(AVFormatContext *s)
{
IcoMuxContext *ico = s->priv_data;
AVIOContext *pb = s->pb;
int i;
avio_seek(pb, 4, SEEK_SET);
avio_wl16(pb, ico->current_image);
for (i = 0; i < ico->nb_images; i++) {
avio_w8(pb, ico->images[i].width);
avio_w8(pb, ico->images[i].height);
if (s->streams[i]->codec->codec_id == AV_CODEC_ID_BMP &&
s->streams[i]->codec->pix_fmt == AV_PIX_FMT_PAL8) {
avio_w8(pb, (ico->images[i].bits >= 8) ? 0 : 1 << ico->images[i].bits);
} else {
avio_w8(pb, 0);
}
avio_w8(pb, 0); // reserved
avio_wl16(pb, 1); // color planes
avio_wl16(pb, ico->images[i].bits);
avio_wl32(pb, ico->images[i].size);
avio_wl32(pb, ico->images[i].offset);
}
av_freep(&ico->images);
return 0;
}
AVOutputFormat ff_ico_muxer = {
.name = "ico",
.long_name = NULL_IF_CONFIG_SMALL("Microsoft Windows ICO"),
.priv_data_size = sizeof(IcoMuxContext),
.mime_type = "image/vnd.microsoft.icon",
.extensions = "ico",
.audio_codec = AV_CODEC_ID_NONE,
.video_codec = AV_CODEC_ID_BMP,
.write_header = ico_write_header,
.write_packet = ico_write_packet,
.write_trailer = ico_write_trailer,
.flags = AVFMT_NOTIMESTAMPS,
};