在C#中优化JPEG压缩级别和文件大小方式

// Save the file with a specific compression level.
private void SaveJpg(Image image, string file_name, long compression)
{
    try
    {
        EncoderParameters encoder_params = new EncoderParameters(1);
        encoder_params.Param[0] = new EncoderParameter(
            System.Drawing.Imaging.Encoder.Quality, compression);

        ImageCodecInfo image_codec_info =
            GetEncoderInfo("image/jpeg");
        File.Delete(file_name);
        image.Save(file_name, image_codec_info, encoder_params);
    }
    catch (Exception ex)
    {
        MessageBox.Show("Error saving file '" + file_name +
            "'\nTry a different file name.\n" + ex.Message,
            "Save Error", MessageBoxButtons.OK,
            MessageBoxIcon.Error);
    }
}

// Return an ImageCodecInfo object for this mime type.
private ImageCodecInfo GetEncoderInfo(string mime_type)
{
    ImageCodecInfo[] encoders = ImageCodecInfo.GetImageEncoders();
    for (int i = 0; i <= encoders.Length; i++)
    {
        if (encoders[i].MimeType == mime_type) return encoders[i];
    }
    return null;
}