I'm not sure if this is the right answer but the method [device setFocusPointOfInterest:point]; takes a CGPoint takes a point ranging from (0,0) to (1,1) where (0,0) is the top left and (1,1) is the bottom right. If you're passing a CGPoint to this method straight from the UIView, it won't focus on the proper point. I suggest you add this:
- (CGPoint)convertToPointOfInterestFromViewCoordinates:(CGPoint)viewCoordinates {
CGPoint pointOfInterest = CGPointMake(.5f, .5f);
CGSize frameSize = [[self videoPreviewView] frame].size;
AVCaptureVideoPreviewLayer *videoPreviewLayer = [self previewLayer];
if ([[videoPreviewLayer videoGravity] isEqualToString:AVLayerVideoGravityResize] ) {
pointOfInterest = CGPointMake(viewCoordinates.y / frameSize.height, 1.f - (viewCoordinates.x / frameSize.width));
} else {
CGRect cleanAperture;
for (AVCaptureInputPort *port in self.visualInput.ports) {
if ([port mediaType] == AVMediaTypeVideo) {
cleanAperture = CMVideoFormatDescriptionGetCleanAperture([port formatDescription], YES);
CGSize apertureSize = cleanAperture.size;
CGPoint point = viewCoordinates;
CGFloat apertureRatio = apertureSize.height / apertureSize.width;
CGFloat viewRatio = frameSize.width / frameSize.height;
CGFloat xc = .5f;
CGFloat yc = .5f;
if ([[videoPreviewLayer videoGravity] isEqualToString:AVLayerVideoGravityResizeAspect] ) {
if (viewRatio > apertureRatio) {
CGFloat y2 = frameSize.height;
CGFloat x2 = frameSize.height * apertureRatio;
CGFloat x1 = frameSize.width;
CGFloat blackBar = (x1 - x2) / 2;
if (point.x >= blackBar && point.x <= blackBar + x2) {
xc = point.y / y2;
yc = 1.f - ((point.x - blackBar) / x2);
}
} else {
CGFloat y2 = frameSize.width / apertureRatio;
CGFloat y1 = frameSize.height;
CGFloat x2 = frameSize.width;
CGFloat blackBar = (y1 - y2) / 2;
if (point.y >= blackBar && point.y <= blackBar + y2) {
xc = ((point.y - blackBar) / y2);
yc = 1.f - (point.x / x2);
}
}
} else if ([[videoPreviewLayer videoGravity] isEqualToString:AVLayerVideoGravityResizeAspectFill]) {
if (viewRatio > apertureRatio) {
CGFloat y2 = apertureSize.width * (frameSize.width / apertureSize.height);
xc = (point.y + ((y2 - frameSize.height) / 2.f)) / y2;
yc = (frameSize.width - point.x) / frameSize.width;
} else {
CGFloat x2 = apertureSize.height * (frameSize.height / apertureSize.width);
yc = 1.f - ((point.x + ((x2 - frameSize.width) / 2)) / x2);
xc = point.y / frameSize.height;
}
}
pointOfInterest = CGPointMake(xc, yc);
break;
}
}
}
return pointOfInterest;
}
to get the correct CGPoint just call [self convertToPointOfInterestFromViewCoordinates:point]; and it will return a CGPoint ranging from (0,0) to (1,1) which you can use for [device setFocusPointOfInterest:point];
