image-optimizer.cs

class Program
    {
        static void Main(string[] args)
        {
            var img = Image.FromFile(@"C:\Users\Mohamed.Elshawaf\Desktop\imageTests\original.png");
            var ratio = .75;
            var height = img.Height;
            var width = img.Width;
            int newHeight = (int)(height * ratio);
            int newWidth = (int)(width * ratio);
            var bitmap = ResizeImage(img, newWidth, newHeight);
            VaryQualityLevel(bitmap);

        }
     
        private static void VaryQualityLevel(Bitmap bitmap)
        {
            // Get a bitmap. The using statement ensures objects  
            // are automatically disposed from memory after use.  
            using (bitmap)
            {
                ImageCodecInfo jpgEncoder = GetEncoder(ImageFormat.Jpeg);

                // Create an Encoder object based on the GUID  
                // for the Quality parameter category.  
                System.Drawing.Imaging.Encoder myEncoder =
                    System.Drawing.Imaging.Encoder.Quality;

                // Create an EncoderParameters object.  
                // An EncoderParameters object has an array of EncoderParameter  
                // objects. In this case, there is only one  
                // EncoderParameter object in the array.  
                EncoderParameters myEncoderParameters = new EncoderParameters(1);

                EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder, 50L);//use this
                myEncoderParameters.Param[0] = myEncoderParameter;
                bitmap.Save(@"C:\Users\Mohamed.Elshawaf\Desktop\imageTests\originalQualityFifty.jpg", jpgEncoder, myEncoderParameters);

                myEncoderParameter = new EncoderParameter(myEncoder, 100L);
                myEncoderParameters.Param[0] = myEncoderParameter;
                bitmap.Save(@"C:\Users\Mohamed.Elshawaf\Desktop\imageTests\originalQualityHundred.jpg", jpgEncoder, myEncoderParameters);

                // Save the bitmap as a JPG file with zero quality level compression.  
                myEncoderParameter = new EncoderParameter(myEncoder, 0L);
                myEncoderParameters.Param[0] = myEncoderParameter;
                bitmap.Save(@"C:\Users\Mohamed.Elshawaf\Desktop\imageTests\originalQualityZero.jpg", jpgEncoder, myEncoderParameters);
            }
        }


        private static ImageCodecInfo GetEncoder(ImageFormat format)
        {
            ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
            foreach (ImageCodecInfo codec in codecs)
            {
                if (codec.FormatID == format.Guid)
                {
                    return codec;
                }
            }
            return null;
        }

        /// <summary>
        /// Resize the image to the specified width and height.
        /// </summary>
        /// <param name="image">The image to resize.</param>
        /// <param name="width">The width to resize to.</param>
        /// <param name="height">The height to resize to.</param>
        /// <returns>The resized image.</returns>
        public static Bitmap ResizeImage(Image image, int width, int height)
        {
            var destRect = new Rectangle(0, 0, width, height);
            var destImage = new Bitmap(width, height);

            destImage.SetResolution(image.HorizontalResolution, image.VerticalResolution);

            using (var graphics = Graphics.FromImage(destImage))
            {
                graphics.CompositingMode = CompositingMode.SourceCopy;
                graphics.CompositingQuality = CompositingQuality.HighQuality;
                graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
                graphics.SmoothingMode = SmoothingMode.HighQuality;
                graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;

                using (var wrapMode = new ImageAttributes())
                {
                    wrapMode.SetWrapMode(WrapMode.TileFlipXY);
                    graphics.DrawImage(image, destRect, 0, 0, image.Width, image.Height, GraphicsUnit.Pixel, wrapMode);
                }
            }

            return destImage;
        }

    }