缩小图像尺寸C#

Question

我的情景:

我希望减少图像大小(10 KB到3 KB)

Answer 1

那么,你想要的是这样的:

// Make sure to include this at the top
using System.Drawing.Imaging;

 

/// <summary> 
/// Saves an image as a jpeg image, with the given quality 
/// </summary> 
/// <param name="path"> Path to which the image would be saved. </param> 
/// <param name="quality"> An integer from 0 to 100, with 100 being the highest quality. </param> 
public static void SaveJpeg (string path, Image img, int quality) 
{ 
    if (quality<0  ||  quality>100) 
        throw new ArgumentOutOfRangeException("quality must be between 0 and 100."); 

     // Encoder parameter for image quality 
     EncoderParameter qualityParam = new EncoderParameter(Encoder.Quality, quality); 
     // JPEG image codec 
     ImageCodecInfo jpegCodec = GetEncoderInfo("image/jpeg"); 
     EncoderParameters encoderParams = new EncoderParameters(1); 
     encoderParams.Param[0] = qualityParam; 
     img.Save(path, jpegCodec, encoderParams); 
} 

/// <summary> 
/// Returns the image codec with the given mime type 
/// </summary> 
private static ImageCodecInfo GetEncoderInfo(string mimeType) 
{ 
     // Get image codecs for all image formats 
     ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders(); 

     // Find the correct image codec 
     for(int i=0; i<codecs.Length; i++) 
         if(codecs[i].MimeType == mimeType) 
             return codecs[i]; 

     return null; 
 } 

然后你可以这样做:

// First load the image somehow
Image myImage = Image.FromFile(pathToImage, true); 
// Save the image with a quality of 50% 
SaveJpeg (destImagePath, myImage, 50); 

请参阅VB论坛和此博客文章中的这篇文章.