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Videos are automatically resized to fit the format. Images in overlay can be resized manually and be placed anywhere on the video. While images in the companion need to meet format's specs. See 4 - Ad Formats for more.
How many stories can I add for each Ad format?
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You may assign any size for the image as long as it is high resolution and doesn't pixelize. The size of the background image URL will depend on the format of your campaign.
In what file can the Ad Formats be exported to?
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