private void CompressedImage(string fileName, long quality)
{
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
Byte[] bytePic = new Byte[fs.Length];
fs.Read(bytePic, 0, bytePic.Length);
MemoryStream stream = new MemoryStream(bytePic);
Bitmap bmp = (Bitmap)Image.FromStream(stream);
ImageCodecInfo myImageCodecInfo = ImageCodecInfo.GetImageEncoders()[1]; //如果下面遍历没有这种图片格式，就默认为jpeg
ImageCodecInfo[] encoders = ImageCodecInfo.GetImageEncoders();
for (int j = 0; j < encoders.Length; j++)
{
if (encoders[j].MimeType == "image/jpeg")
{
myImageCodecInfo = encoders[j];
break;
}
}
System.Drawing.Imaging.Encoder myEncoder = System.Drawing.Imaging.Encoder.Quality; //要操作的是质量
EncoderParameters myEncoderParameters = new EncoderParameters(1); //一个成员，只处理质量
EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, quality); //0为最差质量,100为最好，注意是long类型
myEncoderParameters.Param[0] = myEncoderParameter;
Size s = new Size(bmp.Width, bmp.Height);
Bitmap newBmp = new Bitmap(bmp, s);
MemoryStream ms = new MemoryStream();
newBmp.Save(ms, myImageCodecInfo, myEncoderParameters); //压缩后的流保存到ms
//从流中还原图片
Image image = Image.FromStream(ms);
string curDirectory = Path.GetDirectoryName(Assembly.GetCallingAssembly().GetModules()[0].FullyQualifiedName) + "\\";
//保存图片
image.Save(curDirectory + "pic.jpg");
fs.Dispose();
stream.Dispose();
newBmp.Dispose();
ms.Dispose();
}
demo
