使用C#压缩PNG、JPEG和TIFF图像的方法

Install-Package Aspose.Imaging

// The path to the documents directory.
string dataDir = RunExamples.GetDataDir_PNG();
 
// Load an image from file (or stream)
using (Image image = Image.Load(dataDir + "aspose_logo.png"))
{
    // Loop over possible CompressionLevel range
    for (int i = 0; i <= 9; i++)
    {
        // Create an instance of PngOptions for each resultant PNG, Set CompressionLevel and  Save result on disk
        PngOptions options = new PngOptions();
        options.CompressionLevel = i;
        image.Save(i + "_out.png", options);
    }
}

// The path to the documents directory.
string dataDir = RunExamples.GetDataDir_JPEG();
          
using (var original = Image.Load(dataDir+"ColorGif.gif"))
{
    var jpegOptions = new JpegOptions()
{
    ColorType = JpegCompressionColorMode.Grayscale,
    CompressionType = JpegCompressionMode.Progressive,
          
};
    original.Save("D:/temp/result.jpg", jpegOptions);
}

// The path to the documents directory.
string dataDir = RunExamples.GetDataDir_ModifyingAndConvertingImages();
 
// Load an image through file path location or stream
Image image = Image.Load(dataDir + "SampleTiff.tiff");
 
// Create an instance of TiffOptions for the resultant image
TiffOptions outputSettings = new TiffOptions(TiffExpectedFormat.Default);
 
// Set BitsPerSample, Compression, Photometric mode and graycale palette
outputSettings.BitsPerSample = new ushort[] { 4 };
outputSettings.Compression = TiffCompressions.Lzw;
outputSettings.Photometric = TiffPhotometrics.Palette;
outputSettings.Palette = ColorPaletteHelper.Create4BitGrayscale(false);
image.Save(dataDir + "SampleTiff_out.tiff", outputSettings);