Resizing a big photo makes the new photo very pixelated. !

JohnForza · **Joined:** Jun 30, 2014 **Posts:** 4

GIMP Version: 2.8.10
Operating System: Windows
OS Version: Win 7 / 8.1
GIMP Experience: Beginner Level

Hi there. After resizing a big Photo to a smaller one, to be used in webshop, the resized Photo become very pixelated. How to avoid this ?

sallyanne · **Posted:** Mon Jun 30, 2014 8:30 am **(#2)**

You should be able to make a big photo smaller without any problems but you cannot make it larger afterwards.....I have found you can't any how.

paynekj · **Posted:** Mon Jun 30, 2014 8:34 am **(#3)**

Please explain, step by step, the process you are using to re-size the photo.

JohnForza · **Joined:** Jun 30, 2014 **Posts:** 4

1. Open image. (4.4 MB, 4940x2908 px, resolution 300x300)
2. Click on Scale image (choose new size 200x118 px, keep the same resolution, Cubic)
3. Click on the scale button.

And now the Photo is very pixelated.

How to avoid that ?

paynekj · **Posted:** Mon Jun 30, 2014 9:26 am **(#5)**

I'm not sure I understand what you are expecting from a very large change in size.

Then a thought... Is your image in RGB mode or in indexed mode?

Kevin

This is what I get when I re-size a 4000x3000px RGB image to 200px on the long side:

Attachment:

P1060178_cubic.JPG [ 49.89 KiB | Viewed 4616 times ]

ofnuts · **Joined:** Oct 25, 2010 **Posts:** 4812

JohnForza wrote:

1. Open image. (4.4 MB, 4940x2908 px, resolution 300x300)
2. Click on Scale image (choose new size 200x118 px, keep the same resolution, Cubic)
3. Click on the scale button.

And now the Photo is very pixelated.

How to avoid that ?

Can you attach the 200x118 px image here?

paynekj · **Posted:** Mon Jun 30, 2014 9:36 am **(#7)**

Also make sure you are not viewing it zoomed in:

Attachment:

Untitled2.png [ 380.96 KiB | Viewed 4609 times ]

GnuTux · **Posted:** Mon Jun 30, 2014 9:40 am **(#8)**

JohnForza,

Is it possible that you are viewing the scaled down image in a zoomed state? If you scale the image down to 200x118 px, then view it in your browser (or HTML editor) at a higher (stretched) resolution, the image will appear pixelated and blocky. Ensure that the HTML/CSS code is set to the same resolution as the image, in this case: 200x118 px.

Other than that, it's as paynelk said. You do lose resolution when you scale down a large image, being you throw out a of pixel data, but it should be fairy readable at its native resolution.

JohnForza · **Joined:** Jun 30, 2014 **Posts:** 4

Hi there, -
Tks for spending your time for me.
Here are the original and the resized image.

JohnForza · **Joined:** Jun 30, 2014 **Posts:** 4

In the GIMP window I get following result, after zooming in 200%:

GnuTux · **Posted:** Mon Jun 30, 2014 10:18 am **(#11)**

I'm not sure what you are expecting but scaling that image to 200x118 px isn't going to provide much in the way of resolution. You're tossing ~95% of the pixels you started with.

ofnuts · **Joined:** Oct 25, 2010 **Posts:** 4812

Many straight slanted lines, leading to spatial frequency folding. As usual, the solution is to apply a Gaussian blur to the image first (here by 25px since you are downscaling 25x):

Attachment:

ScaledDownBike.png [ 70.67 KiB | Viewed 1502 times ]