Is there any restriction on the data format that a subclass of AGSDynamicLayer can supply through the -setImageData:forEnvelope: method? I have been creating the NSData object using UIImagePNGRepresentation(), but that function is proving to be too slow for what I am trying to achieve. I do not see a way to supply a mask representing the alpha channel to AGSDynamicLayer when the NSData object is made by UIImageJPEGRepresentation(). That leaves me considering TIFF, but it will take me a bit of time to incorporate libtiff into my project. If TIFF data will not work with AGSDynamicLayer, then I will concentrate on finding some other way to improve performance.