C#图片压缩算法

 1 /// <summary>
 2 /// 壓縮圖片 /// </summary>
 3 /// <param name="fileStream">圖片流</param>
 4 /// <param name="quality">壓縮質量0-100之間 數值越大質量越高</param>
 5 /// <returns></returns>
 6     private byte[] CompressionImage(Stream fileStream, long quality) {
 7         using (System.Drawing.Image img = System.Drawing.Image.FromStream(fileStream)) {
 8             using (Bitmap bitmap = new Bitmap(img)) {
 9                 ImageCodecInfo CodecInfo = GetEncoder(img.RawFormat);
10                 System.Drawing.Imaging.Encoder myEncoder = System.Drawing.Imaging.Encoder.Quality;
11                 EncoderParameters myEncoderParameters = new EncoderParameters(1);
12                 EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, quality);
13                 myEncoderParameters.Param[0] = myEncoderParameter;
14                 using (MemoryStream ms = new MemoryStream()) {
15                     bitmap.Save(ms, CodecInfo, myEncoderParameters);
16                     myEncoderParameters.Dispose();
17                     myEncoderParameter.Dispose();
18                     return ms.ToArray();
19                 }
20             }
21         }
22     }
23 調用:CompressionImage(stream,0L)//最低質量 1M jpg圖大概能壓成180k左右