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Knowledge base Resizing the site generator's (Sitebuilder) customized banner to the authorized format
Resizing the site generator's (Sitebuilder) customized banner to the authorized format
If you don't have any image editing software (Photoshop, ACDSee, etc.) and don't want to use freeware (The Gimp, XnView, etc.), you may use a website that will help you do this directly online:
Reduction-image.com / Pixlr.com / but also: http://www.clubic.com/article-78504-1-retouche-en-ligne-photo.html
Information about banner format can be found here (click here)
Link to this FAQ: