This is very easy to do with imagemagick. You should be able to install it in the Software Center. I would suggest it for batch processing of images.
The batch resizing is incredibly simple (I tested it with Ubuntu 11.10). Use the following command to resize every .jpg file to 200 pixel width, keeping the aspect ratio:
$ convert '*.jpg[200x]' resized%03d.png
This is only scratching the surface of the power of imagemagick. Resizing can be tuned endlessly. For more advanced resizing you have to use the -resize option.
You can limit the resizing to shrinking:
$ convert '*.jpg[300x>]' thumb-300-%03d.png
or enlarging:
$ convert '*.jpg[300x<]' thumb-300-%03d.png
Have look at the geometry documentation to see more options
If you would like to refer to this comment somewhere else in this project, copy and paste the following link:
convert INPUT -resize WIDTH_SIZE OUTPUT
ex:
convert Ble_multigraines_2.PNG -resize 200 test2.png
This is very easy to do with imagemagick. You should be able to install it in the Software Center. I would suggest it for batch processing of images.
The batch resizing is incredibly simple (I tested it with Ubuntu 11.10). Use the following command to resize every .jpg file to 200 pixel width, keeping the aspect ratio:
$ convert '*.jpg[200x]' resized%03d.png
This is only scratching the surface of the power of imagemagick. Resizing can be tuned endlessly. For more advanced resizing you have to use the -resize option.
You can limit the resizing to shrinking:
$ convert '*.jpg[300x>]' thumb-300-%03d.png
or enlarging:
$ convert '*.jpg[300x<]' thumb-300-%03d.png
Have look at the geometry documentation to see more options