High-quality Image Compression

# Region using directives

Using system;

Using system. Web;

Using system. drawing;

Using system. Drawing. imaging;

Using system. Drawing. drawing2d;

 

# Endregion using directives

Public class imageresizer

{

# Region Fields

Static httpserverutility Server = httpcontext. Current. server;

 

# Endregion Fields

 

# Region get Encoder

Public static imagecodecinfo getencoder (string mimetype)

{

Foreach (imagecodecinfo Codec in imagecodecinfo. getimageencoders ())

{

If (codec. mimetype = mimetype)

{

Return codec;

}

}

Return NULL;

}

 

# Endregion get Encoder

 

# Region resize Image

Public static void resizeimage (string originalimagelocation,

Int width, int height, string newimagelocation)

{

Image originalimage = image. fromfile (

Server. mappath (originalimagelocation. Replace ("//","/")));

Resizeimage (originalimage, width, height, newimagelocation );

}

Public static void resizeimage (image originalimage,

Int width, int height, string newimagelocation)

{

//

// Scale the image depending on whether it is portrait or landscape.

Decimal newwidth;

Decimal newheight;

If (originalimage. width/width)> (originalimage. width/height ))

{

Newwidth = width;

Newheight = (int32) math. Ceiling (convert. todecimal ((

Originalimage. Height * newwidth)/originalimage. width ));

If (newheight> height)

{

Newwidth = newwidth * (height/newheight );

Newheight = height;

}

}

Else

{

Newheight = height;

Newwidth = math. Ceiling (convert. todecimal ((

Originalimage. Width * newheight)/originalimage. Height ));

If (newwidth> width)

{

Newheight = newheight * (width/newwidth );

Newwidth = width;

}

}

//

// Create the new image as a bitmap

Bitmap newbitmap = new Bitmap (convert. toint32 (newwidth ),

Convert. toint32 (newheight), pixelformat. format16bpprgb565 );

Graphics G = graphics. fromimage (newbitmap );

G. interpolationmode = interpolationmode. highqualitybicubic;

G. smoothingmode = smoothingmode. antialias;

G. smoothingmode = smoothingmode. highquality;

G. drawimage (originalimage, 0, 0, convert. toint32 (newwidth ),

Convert. toint32 (newheight ));

//

// Save the image using the appropriate encoder with a quality of 98%

Imagecodecinfo codecencoder = imageresizer. getencoder ("image/JPEG ");

Int Quality = 98;

Encoderparameters encodeparams = new encoderparameters (1 );

Encoderparameter qualityparam = new encoderparameter (encoder. quality, quality );

Encodeparams. Param [0] = qualityparam;

Newbitmap. setresolution (72, 72 );

Newbitmap. Save (server. mappath (newimagelocation), codecencoder, encodeparams );

//

// Clean up

G. Dispose ();

Newbitmap. Dispose ();

Originalimage. Dispose ();

}

 

# Endregion resize Image

}