How compress image without change the original height ,width of image in c#

0
votes

I want to make image size smaller then its original size.I am using following code for compress the size images but it increased the image size from 1MB to 1.5MB
Any Other solution for compress large size images without change image original height,width.

    public static byte[] CompressImage(Image img) {

            int originalwidth = img.Width, originalheight = img.Height;

            Bitmap bmpimage = new Bitmap(originalwidth, originalheight);

            Graphics gf = Graphics.FromImage(bmpimage);
            gf.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
            gf.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.AssumeLinear;
            gf.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.NearestNeighbor;

            Rectangle rect = new Rectangle(0, 0, originalwidth, originalheight);
            gf.DrawImage(img, rect, 0, 0, originalwidth, originalheight, GraphicsUnit.Pixel);

            byte[] imagearray;

            using (MemoryStream ms = new MemoryStream())
            {
                bmpimage.Save(ms, ImageFormat.Jpeg);
                imagearray= ms.ToArray();
            }

            return imagearray;
        }
2
c#.netimagesystem.drawing
Can you reword your question? It sounds like you're using "compress" when you mean "downscale" at the same time you're also talking about issues with actual file compression issues with the JPEG file format. – Dai
I want to make image size smaller without losing quality.this is my question. – Shoaib Ijaz

2 Answers

3
votes

You can set the quality level when you save the file as JPEG, which mostly also directly will correlate with file size - the less quality the smaller your output file will be.

Also see How to: Set JPEG Compression Level , for an example see this SO answer.

0
votes

As said by @BrokenGlass you can specify the compression level within the EncoderParameter. Here's a snippet if you want to give a try changing quality: 

public static void SaveJpeg(string path, Image image, int quality)
{
    //ensure the quality is within the correct range
    if ((quality < 0) || (quality > 100))
    {
        //create the error message
        string error = string.Format("Jpeg image quality must be between 0 and 100, with 100 being the highest quality.  A value of {0} was specified.", quality);
        //throw a helpful exception
        throw new ArgumentOutOfRangeException(error);
    }

    //create an encoder parameter for the image quality
    EncoderParameter qualityParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
    //get the jpeg codec
    ImageCodecInfo jpegCodec = GetEncoderInfo("image/jpeg");

    //create a collection of all parameters that we will pass to the encoder
    EncoderParameters encoderParams = new EncoderParameters(1);
    //set the quality parameter for the codec
    encoderParams.Param[0] = qualityParam;
    //save the image using the codec and the parameters
    image.Save(path, jpegCodec, encoderParams);
}