Image resizing shows Poor Quality?

Question

I have image and while re-sizing it gets Poor Quality

enter image description here

My code:

string sFile = "D:\\Testing\\" + txtnewname.Text;
Bitmap newImage = new Bitmap(Convert.ToInt32(txtwidth.Text), Convert.ToInt32(txtHeight.Text));
newImage.SetResolution(image.HorizontalResolution, image.VerticalResolution);

using (Graphics gr = Graphics.FromImage(newImage))
{
    gr.SmoothingMode = SmoothingMode.HighQuality;
    gr.InterpolationMode = InterpolationMode.HighQualityBicubic;
    gr.PixelOffsetMode = PixelOffsetMode.HighQuality;
    gr.DrawImage(image, new Rectangle(0, 0, (Convert.ToInt32(txtwidth.Text)), Convert.ToInt32(txtHeight.Text)));
}
newImage.Save(sFile + ".jpeg", ImageFormat.Jpeg);

Did you mess something up with your screenshots? I wouldn't describe a completely white picture (your "after" picture appears as blank to me) as "Poor Quality"? — CodesInChaos, Sep 02 '13 at 11:08
Did you try saving in a lossless format? Perhaps its the jpeg compression step and not the resizing that decreases quality. — CodesInChaos, Sep 02 '13 at 11:10
i put the images somebody is edited my ques ..sorry for the inconvinence — Aravind, Sep 02 '13 at 11:16
Firstly try to save to PNG(lossless format) and compare quality. Secondly check out this thread http://stackoverflow.com/questions/1484759/quality-of-a-saved-jpg-in-c-sharp — Alezis, Sep 02 '13 at 11:16
@ Dlemsta it RGB only....http://stackoverflow.com/questions/446834/how-to-detect-if-a-jpeg-contains-cmyk-color-profile i tried this...it shows RGB — Aravind, Sep 03 '13 at 04:22

score 0 · Answer 1 · answered Sep 02 '13 at 11:49

0

Problem is not with the saved quality, IMO its quite fine. The problem is different aspect ratio that you are saving new image to. Thats why it looks of different quality than original image.

You must make sure that the new image persists the original image's aspect ratio by enforcing it. Whatever height or width you provide as input, one of them must be automatically set to retain original aspect ratio.

Bitmap originalImage = Bitmap.FromFile(oFile) as Bitmap;
double ar = (double)originalImage.Height/originalImage.Width;
int newHeight = 100;
int newWidth = (int)(newHeight/ar );
Bitmap newImage = new Bitmap(newWidth, newHeight);
//and then do what you want to do

answered Sep 02 '13 at 11:49

Irfan

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@AravindSrinivas, can u send me image file ... see this http://www.fileconvoy.com/ – Irfan Sep 02 '13 at 12:23
also what height and width? – Irfan Sep 02 '13 at 12:25
i changed default height...but quality is same – Aravind Sep 02 '13 at 13:15

Image resizing shows Poor Quality?

1 Answers1