Post

Replies

Boosts

Views

Activity

Urgent: XCode git remove files of another project
I dragged a group of files from one XCode project to another. I noticed XCode copied the whole project folder instead of the selected group of files. I immediately selected the copied project folder and deleted it, and selected "Remove References only" as I had a bad experience earlier where I chose to delete the files (in which case the files got deleted from the original project). But now when I commit the changes to git, it shows me list of 1300 files from the original project to commit, even though they are not there in the project. I search the all the project subfolders and those files are no where in the project. What do I do for git to forget those files?
0
0
501
Feb ’22
Combining two apps in XCode
I have two XCode workspaces, both the workspaces have multiple targets. Each target in both the workspaces have storyboard file called Main.storyboard. My problem is to combine one target in the first workspace with a second in another. What is the right approach to merge the targets?
0
0
359
Feb ’22
What exactly is the use of CIKernel DOD?
I wrote the following Metal Core Image Kernel to produce constant red color. extern "C" float4 redKernel(coreimage::sampler inputImage, coreimage::destination dest) {     return float4(1.0, 0.0, 0.0, 1.0); } And then I have this in Swift code: class CIMetalRedColorKernel: CIFilter {     var inputImage:CIImage?     static var kernel:CIKernel = { () -> CIKernel in         let bundle = Bundle.main         let url = bundle.url(forResource: "Kernels", withExtension: "ci.metallib")!         let data = try! Data(contentsOf: url)         return try! CIKernel(functionName: "redKernel", fromMetalLibraryData: data)     }()     override var outputImage: CIImage? {         guard let inputImage = inputImage else {             return nil         }         let dod = inputImage.extent         return CIMetalTestRenderer.kernel.apply(extent: dod, roiCallback: { index, rect in             return rect         }, arguments: [inputImage])     } } As you can see, the dod is given to be the extent of the input image. But when I run the filter, I get a whole red image beyond the extent of the input image (DOD), why? I have multiple filters chained together and the overall size is 1920x1080. Isn't the red filter supposed to run only for DOD rectangle passed in it and produce clear pixels for anything outside the DOD?
4
0
1.5k
Feb ’22
AVPlayer seek completion handler not called
@AVFoundation Engineers, I get this bug repeatedly when using AVComposition & AVVideoComposition. Sometimes AVPlayer seek to time completion handler is not called. I check for a flag whether seek is in progress before placing another seek request. But if the completion handler is never invoked, all further seeks stall as flag remains true. What is a reliable way to know seek is not in progress before initiating another seek request. playerSeeking = true         player.seek(to: time, toleranceBefore: .zero, toleranceAfter: .zero) { [weak self] completed             if !completed {                 NSLog("Seek not completed \(time.seconds)")             }             guard let self = self else {                 return             }             self.playerSeeking = false             if self.player.rate == 0.0 {                 self.updateButtonStates()             }         }
2
0
1.5k
Feb ’22
AVVideoComposition startRequest early return without calling finishWithComposedVideoFrame
@AVFoundationEngineers I browsed through AVCustomEdit sample code and notice the following: - (void)startVideoCompositionRequest:(AVAsynchronousVideoCompositionRequest *)request { @autoreleasepool { dispatch_async(_renderingQueue,^() { // Check if all pending requests have been cancelled if (_shouldCancelAllRequests) { [request finishCancelledRequest]; } else { NSError *err = nil; // Get the next rendererd pixel buffer CVPixelBufferRef resultPixels = [self newRenderedPixelBufferForRequest:request error:&err]; if (resultPixels) { // The resulting pixelbuffer from OpenGL renderer is passed along to the request [request finishWithComposedVideoFrame:resultPixels]; CFRelease(resultPixels); } else { [request finishWithError:err]; } } } } The startVideoComposition request returns early without calling finishWithComposedVideoFrame as the processing takes place asynchronously in a dispatchQueue. However, the documentation of startVideoCompositionRequest states the following: Note that if the custom compositor's implementation of -startVideoCompositionRequest: returns without finishing the composition immediately, it may be invoked again with another composition request before the prior request is finished; therefore in such cases the custom compositor should be prepared to manage multiple composition requests. But I don't see anything in the code that is prepared to handle multiple composition requests of same video frame. How is one supposed to handle this case?
0
0
505
Jan ’22
Implementing Tone Curves using Metal/Core Image
I am trying to develop tone curves filter using Metal or Core Image as I find CIToneCurve filter is having limitations (number of points are atmost 5, spline curve it is using is not documented, and sometimes output is a black image even with 4 points). Moreover it's not straightforward to have separate R,G,B curves independently. I decided to explore other libraries that implement tone curve and the only one that I know is GPUImage (few others borrow code from the same library). But the source code is too cryptic to understand and I have [doubts] about the manner in which it is generating look up texture (https://stackoverflow.com/questions/70516363/gpuimage-tone-curve-rgbcomposite-filter). Can someone explain how to correctly implement R,G,B, and RGB composite curves filter like in Mac Photos App?
1
1
1.8k
Dec ’21
CIColorCube load lut data
I have a .cube file storing LUT data, such as this: TITLE "Cool LUT" LUT_3D_SIZE 64 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0157 0.0000 0.0000 0.0353 0.0000 0.0000 My question is how do I load required NSData that can be used in CIColorCube filter? When using Metal, I convert this data into MTLTexture using AdobeLUTParser. Not sure what to do in case of CoreImage.
0
0
766
Dec ’21
Metal Core Image passing sampler arguments
I am trying to use a CIColorKernel or CIBlendKernel with sampler arguments but the program crashes. Here is my shader code which compiles successfully. extern "C" float4 wipeLinear(coreimage::sampler t1, coreimage::sampler t2, float time) { float2 coord1 = t1.coord(); float2 coord2 = t2.coord(); float4 innerRect = t2.extent(); float minX = innerRect.x + time*innerRect.z; float minY = innerRect.y + time*innerRect.w; float cropWidth = (1 - time) * innerRect.w; float cropHeight = (1 - time) * innerRect.z; float4 s1 = t1.sample(coord1); float4 s2 = t2.sample(coord2); if ( coord1.x > minX && coord1.x < minX + cropWidth && coord1.y > minY && coord1.y <= minY + cropHeight) { return s1; } else { return s2; } } And it crashes on initialization. class CIWipeRenderer: CIFilter { var backgroundImage:CIImage? var foregroundImage:CIImage? var inputTime: Float = 0.0 static var kernel:CIColorKernel = { () -> CIColorKernel in let url = Bundle.main.url(forResource: "AppCIKernels", withExtension: "ci.metallib")! let data = try! Data(contentsOf: url) return try! CIColorKernel(functionName: "wipeLinear", fromMetalLibraryData: data) //Crashes here!!!! }() override var outputImage: CIImage? { guard let backgroundImage = backgroundImage else { return nil } guard let foregroundImage = foregroundImage else { return nil } return CIWipeRenderer.kernel.apply(extent: backgroundImage.extent, arguments: [backgroundImage, foregroundImage, inputTime]) } } It crashes in the try line with the following error: Fatal error: 'try!' expression unexpectedly raised an error: Foundation._GenericObjCError.nilError If I replace the kernel code with the following, it works like a charm: extern "C" float4 wipeLinear(coreimage::sample_t s1, coreimage::sample_t s2, float time) { return mix(s1, s2, time); }
1
0
1.5k
Nov ’21
AVCaptureDevice isCenterStageEnabled KVO not fired
@AVFoundationEngineers I am trying to observe isCenterStageEnabled property as follows: AVCaptureDevice.self.addObserver(self, forKeyPath: "isCenterStageEnabled", options: [.initial, .new], context: &CapturePipeline.centerStageContext) I have set the centerStageControlMode to .cooperative. The KVO fires only when I do make changes to property AVCaptureDevice.isCenterStageEnabled in my code. KVO is NOT fired when the user toggles the centerStage property from Control Center. Is this a bug?
0
0
487
Oct ’21
AVAssetWriter error -12870 after building with XCode 13
The AppStore version of my app works perfectly fine. But the moment I build the same code with XCode 13, AVAssetWriter fails with errors at the very beginning itself both on iOS 14 and iOS 15. This happens with Multicam session only. Domain=AVFoundationErrorDomain Code=-11800 "The operation could not be completed" UserInfo={NSLocalizedFailureReason=An unknown error occurred (-12780) I am wondering what could be wrong. I even passed default settings to AVAssetWriter (the recommended ones). Update: It turned out to be an issue with audio settings.
2
0
711
Oct ’21