For the image height I solved by removing all fixed heights in the css files for the isotope classes.
I will handle the vertical size by pre processing images before uploading on the website.
The thing that I don't know how to handle is the width, in the original template it is 240px and it uses the chached image generated from K2 with the "small" size.
To add the image with double width in the portfolio somehow I need to:
- add a css class to set width: 480px
- indicate that the image to be used is not the "small" (filename_S) but the "medium" (filename_M)
The only Idea that I have is to create a dedicated extra field on K2 to handle width, and create an if condition on category_item.php to verify the value of that extra field and decide whether to set or not the before mentioned bullet points.
Does anyone have a better idea?