shrink an image

Question

User-125499312 posted

if <g class="gr_ gr_30 gr-alert gr_tiny gr_spell gr_inline_cards gr_run_anim ContextualSpelling multiReplace" id="30" data-gr-id="30">i</g> have an image (jpg, png, etc..) <g class="gr_ gr_66 gr-alert gr_tiny gr_spell gr_inline_cards gr_run_anim ContextualSpelling multiReplace" id="66" data-gr-id="66">i</g> would like to shrink to maintain its proportions

<g class="gr_ gr_149 gr-alert gr_tiny gr_spell gr_inline_cards gr_run_anim ContextualSpelling multiReplace" id="149" data-gr-id="149">i</g> would like to take the height or the width - whichever is bigger and shrink it down to a specific size and maintain the proportions of the image.

how would <g class="gr_ gr_362 gr-alert gr_tiny gr_spell gr_inline_cards gr_run_anim ContextualSpelling multiReplace" id="362" data-gr-id="362">i</g> do this?

thx for ur help

Answer 1

User-943250815 posted

To make changes on images I use ImageProcessor you can get it on Nuget
For resize you get a sample here http://imageprocessor.org/imageprocessor/imagefactory/

Or you can work with System.Drawing

Answer 2

User-1174608757 posted

Hi yzidell,

According to your description, I have made a sample here.I suggest you to use a class to shrink your image.

You could firstly get the image in the folder by entering the path, then you could resize your image depend on its width or height ,or just the whole picture.

Here is the demo, I hope it could help you.

class1: 

  public void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
        {
            System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath);// get the image in the path you enter

            int towidth = width;
            int toheight = height;

            int x = 0;
            int y = 0;
            int ow = originalImage.Width;
            int oh = originalImage.Height;

            switch (mode)
            {
                case "HW": //"HW"  is to  resize the image according the width and height specified which may cause distortion
                    break;
                case "W": //"W" is to resize the image according to the Width
                    toheight = originalImage.Height * width / originalImage.Width;
                    break;
                case "H"://"H" is to resize the image according to the height
                    towidth = originalImage.Width * height / originalImage.Height;
                    break;
                case "Cut"://"Cut" is to resize the image according to the width and height specified which doesn’t cause distortion.
                    if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
                    {
                        oh = originalImage.Height;
                        ow = originalImage.Height * towidth / toheight;
                        y = 0;
                        x = (originalImage.Width - ow) / 2;
                    }
                    else
                    {
                        ow = originalImage.Width;
                        oh = originalImage.Width * height / towidth;
                        x = 0;
                        y = (originalImage.Height - oh) / 2;
                    }
                    break;
                default:
                    break;
            }


            System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight);


            Graphics g = System.Drawing.Graphics.FromImage(bitmap);


            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;


            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;


            g.Clear(Color.Transparent);


            g.DrawImage(originalImage, new Rectangle(0, 0, towidth, toheight),
             new Rectangle(x, y, ow, oh),
             GraphicsUnit.Pixel);
            try
            {

                bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);

            }
            catch (System.Exception e)
            {
                throw e;
            }
            finally
            {
                originalImage.Dispose();
                bitmap.Dispose();
                g.Dispose();
            }


        }

In code behind , you could write as below:

 public partial class image : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            string path = Server.MapPath("~/images");
            // get all the absolute pathes  of files in the original folder
            string[] images = Directory.GetFiles(path);
            //get the absolute path of the targeted folder
            string target = Server.MapPath("~/NewFolder2");    
            Class1 resizePicture = new Class1();           
            foreach (var item in images)
            {
                //choose the way you would like to resize the picture
                resizePicture.MakeThumbnail(item, target + "/" + item.Substring(item.LastIndexOf("\\")), 300, 300, "Cut");
                // delete the original images
                File.Delete(item);
            }
        }
    }

 you could now find the picture in folder has been shrinked as below

Best Regards

Wei Zhang