Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Possible Duplicate:
Program to automate image resize

Hello I have a folder with 100 images and I want to change their pixel size is there an easy way to do it simultaneously to all of them, instead of picking them one by one?Thanks in advance! My operating system is Mac OS

share|improve this question

marked as duplicate by Sathya, harrymc, ChrisF, Ivo Flipse Sep 11 '10 at 11:49

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Change pixel size? Do you mean 'change resolution' (resize- change amount of pixels), or 'change dpi' (more accurately ppi)? You cannot change the pixel size, as a pixel is a pixel. You need to change monitors to change the size of a pixel. – paradroid Sep 9 '10 at 14:04
Related Program to automate image resize – Sathya Sep 9 '10 at 14:12

Use ImageMagick's convert tool:

convert files*.png -set filename:area "%wx%h" -resize 50% "resized/-%[filename:area]small.png"
share|improve this answer
seems like a good option thanks!can you give an example for converting images to specific width and height (lets say 1024 768)?Also the concept is to be able to convert multiple images at that what is happening in the example? – rabidmachine9 Sep 9 '10 at 12:59
@rabidmachine9: Here is an example from the page I linked to: convert dragon.gif -resize 64x64 resize_dragon.gif. Instead of a percentage, you just use the desired dimensions. This preserves the aspect ratio. You can override that though by adding an escaped exclamation point (64x64\!) and it will stretch or compress the aspect ratio. – Dennis Williamson Sep 9 '10 at 13:06
In my example, multiple files are selected using file globbing (files*.png) and a renaming operation is done using the -set operator and the filespec in quotes. – Dennis Williamson Sep 9 '10 at 13:07

If you have Photoshop, you can record your own Actions then run them with Batch processing across the Folder. I found good directions here:

You also can resize a folder of images using Photoshop if they are in the JPEG, TIFF or PSD format. This is also only useful if all the images have the same dimensions like from a camera.

  1. Select File > Scripts > Image Processor...
  2. In the Image Processor dialog box, step 1, press the Select Folder... button and select the folder with the images.
  3. In step 2, select the location where the processed images will go.
  4. Select the file type and the Resize to Fit box giving the dimensions.
share|improve this answer

IF you want easy get microsoft's power tool: microsoft image resizer

Select Right-Click Resize.

share|improve this answer
The OP is using OS X. – Dennis Williamson Sep 9 '10 at 15:20

alt text

  • GraphicConverter

  • As a cool trick you can re-size using the preview and the automator

The below is an extract from a site , the site is mentioned below

Say you want to resize an image (or lots of images) to half its size. To do this, drag the Scale Images action over to the right hand side. A dialog box will appear asking if you want the workflow to keep a copy of the original image or not. If you click Add, the workflow will make a copy of your image on the Desktop and resize that instead of the original. Otherwise, it will simply replace the image with its resized version.

The next step is to choose how you want to scale your image. You can set it to a certain width or a percentage of its original size. Once you have chosen, choose Save As from the File menu and give it a name like Resize Images. From the File Format pop-up menu choose Application. The Desktop is a good place to save it.

Find an image file and drag it onto the Resize Images icon. A copy of the image at half the size should appear on the Desktop

Have a look here

share|improve this answer
Both are Windows tools. – Sathya Sep 9 '10 at 14:14
Updated my answer – subanki Sep 9 '10 at 15:21
up vote 0 down vote accepted

Finally it can be done really easy with preview...You just open as many pictures as you like then you go to Tools->Adjust Size you choose dimensions in pixels (or whatever)and click OK! so simple...thanks for all the answers!

share|improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.