ios - UIImageJPEGRepresentation returns nil (on a device - OK on Simulator) -


i nil on ios device (works ok on simulator or playground) when create create barcode uiimage generatebarcode("abcdef") , call uiimagejpegrepresentation or uiimagepngrepresentation.

there still wrong in uiimage debugger cannot display uiimage either. image exists, cgimage property set uiimagejpegrepresentation doesn't it.

i have tried solve per: uiimagejpegrepresentation returns nil

class func generatebarcode(from string: string) -> uiimage? {       let data = string.data(using: string.encoding.ascii)        if let filter = cifilter(name: "cicode128barcodegenerator") {         filter.setvalue(data, forkey: "inputmessage")         if let ciimage = filter.outputimage {               if let cgimange = convertciimagetocgimage(inputimage: ciimage) {                 return uiimage(cgimage: cgimange)             }         }       }       return nil   }   class func convertciimagetocgimage(inputimage: ciimage) -> cgimage? {     let context = cicontext(options: nil)     if let cgimage = context.createcgimage(inputimage, from: inputimage.extent) {         return cgimage     }     return nil }


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