Why properties method of CIImage returns nil
ciimage, core-image, ios, iphone
Solution
I was having this same problem. Turns out the properties dictionary is only non nil if you use the imageWithData: or imageWithContentsOfURL: to create the CIImage.
It's not documented well at all. Check out WWDC 2013 session 509.
Problem
I'm developing an application using coreImage framework.I created a CIImage from UIImage. ``` CIImage *image = [CIImage imageWithCGImage:self.canvasImage.CGImage]; ``` here self.canvasImage is a UIImage,I debug it and object image is being created by compiler with some memory. i'm creating a NSDictionary object returned by properties method using following code. ``` NSDictionary *opts =[image properties] ; ``` here my opts object is being assign with nil value. i searched it but didn't found the solution,why properties method is returning nil value?