Question

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How to Resize Image and save in folder?

I would like to resize and save as images in a given folder. But i want to do it with maximum possible quality. I am willing to use third party software.

Like paint.net or photoshop.

So what is the best possible way of achieving this ?

Thank you.

Answer 1

Disclaimer: The following link/code is from my blog:

You should take a look at this post on my site http://samuelhaddad.com/2011/01/26/net-high-quality-thumbnail-generation/

The code from the post looks something like:

//Image Resize Helper Method
private static Bitmap ResizeImage(String filename, int maxWidth, int maxHeight)
{
    using (Image originalImage = Image.FromFile(filename))
    {
        //Caluate new Size
        int newWidth = originalImage.Width;
        int newHeight = originalImage.Height;
        double aspectRatio = (double)originalImage.Width / (double)originalImage.Height;
        if (aspectRatio <= 1 && originalImage.Width > maxWidth)
        {
            newWidth = maxWidth;
            newHeight = (int)Math.Round(newWidth / aspectRatio);
        }
        else if (aspectRatio > 1 && originalImage.Height > maxHeight)
        {
            newHeight = maxHeight;
            newWidth = (int)Math.Round(newHeight * aspectRatio);
        }
        Bitmap newImage = new Bitmap(newWidth, newHeight);
        using (Graphics g = Graphics.FromImage(newImage))
        {
            //--Quality Settings Adjust to fit your application
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBilinear;
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            g.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
            g.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
            g.DrawImage(originalImage, 0, 0, newImage.Width, newImage.Height);
            return newImage;
        }
    }
}

You can wrap that in a for loop for batch processing.