MaxDiff

GifOptions.MaxDiff property

Gets or sets the maximum allowed pixel difference. If greater than zero, lossy compression will be used. Recommended value for optimal lossy compression is 80. 30 is very light compression, 200 is heavy. It works best when only little loss is introduced, and due to limitation of the compression algorithm very high loss levels won’t give as much gain. The range of allowed values is [0, 1000].

public int MaxDiff { get; set; }

Examples

This example shows how to save a BMP image to GIF format using various options.

[C#]

string dir = "c:\\temp\\";

using (Aspose.Imaging.Image bmpImage = new Aspose.Imaging.FileFormats.Bmp.BmpImage(1000, 1000))
{
    // Fill the entire image with the blue-yellow gradient.
    Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
            new Aspose.Imaging.Point(0, 0),
            new Aspose.Imaging.Point(bmpImage.Width, bmpImage.Height),
            Aspose.Imaging.Color.Blue,
            Aspose.Imaging.Color.Yellow);

    Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(bmpImage);
    graphics.FillRectangle(gradientBrush, bmpImage.Bounds);

    Aspose.Imaging.ImageOptions.GifOptions saveOptions = new Aspose.Imaging.ImageOptions.GifOptions();

    // The number of bits required to store a color, minus 1.
    saveOptions.ColorResolution = 7;

    // Palette correction means that whenever image is exported to GIF the source image colors will be analyzed
    // in order to build the best matching palette (in case image Palette does not exist or not specified in the options)
    saveOptions.DoPaletteCorrection = true;

    // Load a GIF image in a progressive way.
    // An interlaced GIF doesn't display its scanlines linearly from top to bottom, but instead reorders it
    // so the content of the GIF becomes clear even before it finishes loading.
    saveOptions.Interlaced = true;

    // Save as a lossless GIF.
    using (System.IO.Stream stream = System.IO.File.OpenWrite(dir + "output.gif"))
    {
        bmpImage.Save(stream, saveOptions);
        System.Console.WriteLine("The size of the lossless GIF: {0} bytes.", stream.Length);
    }

    // Set the maximum allowed pixel difference. If greater than zero, lossy compression will be used.
    // The recommended value for optimal lossy compression is 80. 30 is very light compression, 200 is heavy.
    saveOptions.MaxDiff = 80;

    // Save as a lossy GIF.
    using (System.IO.Stream stream = System.IO.File.OpenWrite(dir + "output.lossy.gif"))
    {
        bmpImage.Save(stream, saveOptions);
        System.Console.WriteLine("The size of the lossy GIF: {0} bytes.", stream.Length);
    }
}

//The output may look like this:
//The size of the lossless GIF: 212816 bytes.
//The size of the lossy GIF: 89726 bytes.

See Also

LoopsCount PixelAspectRatio