private void GetBackgroundColor(IWICMetadataQueryReader wicMetadataQueryReader)
{
// 如果图片里面包含了 global palette 就需要获取 palette 和背景色
var propertyVariant = new PROPVARIANT();
wicMetadataQueryReader.GetMetadataByName("/logscrdesc/GlobalColorTableFlag", ref propertyVariant);
byte backgroundIndex = 0;
var globalPalette = (propertyVariant.Type & VARTYPE.VT_BOOL) == VARTYPE.VT_BOOL &&
propertyVariant.Value.UI1 > 0;
if (globalPalette)
{
propertyVariant = new PROPVARIANT();
wicMetadataQueryReader.GetMetadataByName("/logscrdesc/BackgroundColorIndex", ref propertyVariant);
if ((propertyVariant.Type & VARTYPE.VT_UI1) == VARTYPE.VT_UI1)
{
backgroundIndex = propertyVariant.Value.UI1;
}
var wicPalette = WicImagingFactory.CreatePalette();
WicBitmapDecoder.CopyPalette(wicPalette);
}
}
static void CopyGif()
{
using (var dec = WicBitmapDecoder.Load(@"source.gif"))
{
var reader = dec.GetMetadataQueryReader();
Dump(reader);
Console.WriteLine();
foreach (var frame in dec)
{
Console.WriteLine(frame.Size);
reader = frame.GetMetadataReader();
Dump(reader);
Console.WriteLine();
}
using (var encoder = WICImagingFactory.CreateEncoder(dec.ContainerFormat))
{
using (var file = File.OpenWrite("test.gif"))
{
var mis = new ManagedIStream(file);
encoder.Initialize(mis);
foreach (var frame in dec)
{
var newFrame = encoder.CreateNewFrame();
newFrame.Initialize();
var md = frame.GetMetadataReader().Enumerate();
using (var writer = newFrame.GetMetadataQueryWriter())
{
writer.EncodeMetadata(md);
// change delay here
writer.SetMetadataByName("/grctlext/Delay", (ushort)5);
}
if (frame.Palette != null)
{
newFrame.SetPalette(frame.Palette.ComObject);
}
newFrame.WriteSource(frame.ComObject);
newFrame.Item1.Commit();
}
encoder.Commit();
}
}
}
}
private Bitmap LoadBitmap(string path)
{
using (WicBitmapDecoder decoder = ImagingFactory.CreateDecoder(ImagePath, Guid.Empty, DesiredAccess.Read, DecodeOptions.MetadataCacheOnDemand))
{
using (WicBitmapFrameDecode frame = decoder.GetFrame(0))
{
using (WicFormatConverter converter = ImagingFactory.CreateFormatConverter())
{
converter.Convert(frame, WicPixelFormats.PixelFormat32bppPBGRA, BitmapDitherType.None, null, 0, BitmapPaletteType.Custom);
return(RenderTarget.CreateBitmap(converter, new BitmapProperties()));
}
}
}
}
static void Dump(string path)
{
//using (var bmp = WicBitmapSource.Load(path))
//{
//}
using (var dec = WicBitmapDecoder.Load(path))
{
var reader = dec.GetMetadataQueryReader();
Dump(reader);
Console.WriteLine();
foreach (var frame in dec)
{
Console.WriteLine(frame.Size);
reader = frame.GetMetadataReader();
Dump(reader);
Console.WriteLine();
}
}
}
