If you transfer via SOAP images can be transferred as follows:
1. The xml file such as the example below
2. A string array of base64 encoded images
3. A string array of image name
The two arrays must have the same number of elements and provide each image with a name. The attribute in the xml file connects the image to the ad using the name.
It is not possible to point to the images remotely. Image files must be transferred for them to be included in the ad.
Optimal image size is 1600x1600 px