The AVVideoCodecJPEG symbol was deprecated in iOS 11.0. We may want to use AVVideoCodecTypeJPEG instead

modules/videoio/src/cap_ios_photo_camera.mm

@@ -139,7 +139,7 @@
 {
     // setup still image output with jpeg codec
     self.stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
-    NSDictionary *outputSettings = [NSDictionary dictionaryWithObjectsAndKeys:AVVideoCodecJPEG, AVVideoCodecKey, nil];
+    NSDictionary *outputSettings = [NSDictionary dictionaryWithObjectsAndKeys:AVVideoCodecTypeJPEG, AVVideoCodecKey, nil];
     [self.stillImageOutput setOutputSettings:outputSettings];
     [self.captureSession addOutput:self.stillImageOutput];