Select JPG Format
- JPGs are the most efficient way of keeping file size low while keeping quality high.
- Be sure that the file you export includes the .jpg extension. This should be added automatically by your computer
- It is possible to accidentally save a .png file with a .jpg extension; however this will cause an error. To avoid this problem, always triple check that your export setting is set to JPG
Check the Pixel Size
- GAP designs labelled 300×600 are actually be 600×1200 pixels (retina). While this is appropriate for HTML5 banner assets, it is not appropriate for backup images.
- backup images should never be supplied at retina size
- So, for a 300×600 banner, the backup image should be 300×600 pixels not 600×1200 retina size
Check the File Size
- Most ad servers require backup images to be 40KB or less, which means you might find some pixelation when exporting your backup images.
- Luckily, as we discussed in the introduction, when your HTML5 banners are coded properly, it is unlikely that your backup image will be served very often
IMPORTANT TO NOTE: Backup Images must be saved at less than 40K or your HTML5 banners will be rejected by your media agency
IMPORTANT TO NOTE: A quick reminder that HTML5 banners need to be properly packaged prior to providing to your media agency for trafficking. Please see our Tutorials on how to package your animated HTML5 banners for delivery here