public static PngInfo GetInfo(Stream stream)
{
if (stream == null)
{
throw new ArgumentNullException("stream");
}
PngReader pngReader = new PngReader(stream);
pngReader.ShouldCloseStream = false;
pngReader.End();
PngInfo result = default(PngInfo);
result.Width = pngReader.ImgInfo.Cols;
result.Height = pngReader.ImgInfo.Rows;
if (pngReader.ImgInfo.BitDepth == 8 && pngReader.ImgInfo.Channels == 4)
{
result.Format = Format.RGBA8;
}
else if (pngReader.ImgInfo.BitDepth == 8 && pngReader.ImgInfo.Channels == 3)
{
result.Format = Format.RGB8;
}
else if (pngReader.ImgInfo.BitDepth == 8 && pngReader.ImgInfo.Channels == 2 && pngReader.ImgInfo.Greyscale)
{
result.Format = Format.LA8;
}
else if (pngReader.ImgInfo.BitDepth == 8 && pngReader.ImgInfo.Channels == 1 && pngReader.ImgInfo.Greyscale)
{
result.Format = Format.L8;
}
else
{
if (pngReader.ImgInfo.BitDepth != 8 || pngReader.ImgInfo.Channels != 1 || !pngReader.ImgInfo.Indexed)
{
throw new InvalidOperationException("Unsupported PNG pixel format.");
}
result.Format = Format.Indexed;
}
return(result);
}
protected override async Task OnInitializedAsync()
{
png = await Manager.GetPngInfo(CurrentNode);
}
