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Why do some of my images appear distorted after I upload them via UploadSiteHostedPictures?
Often the cause of the distortion from a particular corruption of the source images provided to UploadSiteHostedPictures. Often, the 'corruption' in the source image is not visible to naked eye, but contains an Alpha channel transparency(which can also impose using any of image processing softwares available). Png files support alpha transparency but UploadSiteHostedPictures will convert all png files to Jpeg and jpeg doesnt support alpha transparency.
When this happens and an image is moved to a format with no alpha support and it can easily became corrupted. So there is no support this type of image with applied transparencies by the eBay framework.