我使用此代码将JPG图像转换为PNG 8. 代码有效,但图像看起来有颗粒感。我做了一个导出在Photoshop中的PNG 8,它看起来更顺畅,没有粮食。为什么PngBitmapEncoder类会让我的图像看起来有颗粒感?
注意:8位PNG
任何图像大师在那里,可以帮助?
我的代码:
Image ImageFile = Image.FromFile(@"C:\Documents and Settings\dvela\My Documents\Downloads\pngtest\Batman01.jpg");
Rectangle NewSize = new Rectangle();
NewSize.Width = 112;
NewSize.Height = (NewSize.Width * ImageFile.Height)/ImageFile.Width;
Bitmap image = new Bitmap(NewSize.Width, NewSize.Height);
Graphics graphics = Graphics.FromImage(image);
graphics.CompositingQuality = CompositingQuality.HighQuality;
graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;
graphics.SmoothingMode = SmoothingMode.HighQuality;
graphics.DrawImage(ImageFile, NewSize);
FormatConvertedBitmap fcb = new FormatConvertedBitmap(System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(image.GetHbitmap(), IntPtr.Zero, Int32Rect.Empty, BitmapSizeOptions.FromWidthAndHeight(NewSize.Width, NewSize.Height)), PixelFormats.Indexed8, BitmapPalettes.Halftone256Transparent, 0.5);
PngBitmapEncoder pngBitmapEncoder = new PngBitmapEncoder();
pngBitmapEncoder.Interlace = PngInterlaceOption.Off;
pngBitmapEncoder.Frames.Add(BitmapFrame.Create(fcb));
using (Stream fileStream = File.Open(@"C:\Documents and Settings\dvela\My Documents\Downloads\pngtest\test.png", FileMode.Create))
{
pngBitmapEncoder.Save(fileStream);
}
你可以发布这两个图片,或其裁剪版本? – 2009-06-03 15:29:26