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Questions tagged [cvpixelbuffer]

159 questions
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Correct way to draw/edit a CVPixelBuffer in Swift in iOS

Is there a standard performant way to edit/draw on a CVImageBuffer/CVPixelBuffer in swift? All the video editing demos I've found online overlay the drawing (rectangles or text) on the screen and don't directly edit the CVPixelBuffer. UPDATE I tried…
bias
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How to get image data based on ARFaceAnchor or node position?

I'm trying to create a 2D face unwrap image from a live camera feed from an ARKit session. I see there is another question about mapping an image onto a mesh. My question is different - it is about generating an image (or many smaller images) from…
Alex Stone
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RGB values of CIImage pixel

I want to access the average colour value of a specific area of CVPixelBuffer that I get from ARFrame in real-time. I managed to crop the image, use filter to calculate average colour and after converting to CGImage I get the value from the pixel…
RealUglyDuck
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UIImage obtaining CVPixelBuffer Removes Alpha

The function below takes in an UIImage and returns a CVPixelBuffer from the UIImage but it removes the alpha channel. class func pixelBufferFromImage(image: UIImage, pixelBufferPool: CVPixelBufferPool, size: CGSize) -> CVPixelBuffer { var…
impression7vx
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Retrieve the last frame of live camera preview in swift

I have an AR app where the view is constantly showing what the back camera is seeing and sending each frame for analysis to VisionRequest. When the object was identified, I would like to capture that particular last frame and save it as a regular…
Ayrad
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How to turn a CALayer into a CVPixelBuffer efficiently?

I want to find a way to replace the CALayer function "layer.render(in: context)" , which can more efficiently if let context = CGContext(data: pixelData, width: Int(contextSize.width), height: Int(contextSize.height), bitsPerComponent: 8,…
coderLee
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CMSampleBuffer frame converted to vImage has wrong colors

I’m trying to convert CMSampleBuffer from camera output to vImage and later apply some processing. Unfortunately, even without any further editing, frame I get from buffer has wrong colors: Implementation (Memory management and errors are not…
Dawid
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ios / CoreML - The input type is MultiArray when keras model is converted to CoreML

I am trying to train a keras model and convert it to coreML model using keras 1.2.2 and TensorFlow backend. This is for a classification task. The input to CoreML is being shown as MultiArray. I need this to be Image or something like…
skr
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Resize a CVPixelBuffer

I'm trying to resize a CVPixelBuffer to a size of 128x128. I'm working with one that is 750x750. I'm currently using the CVPixelBuffer to create a new CGImage, which I resize then convert back into a CVPixelBuffer. Here is my code: func…
enjoysturtles
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create local movie out of `CVPixelBufferRef` which gets trimmed at the beginning after some time

I do have lots of CVPixelBufferRef which I would like to append to a movie in "real time", i.e. I get 50 - 60 CVPixelBufferRef per second (as they are frames) and would like to create a local video out of it. Even better would be if I could have…
swalkner
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iOS CVPixelBufferCreate leaking memory in swift 2

I'm trying to convert an image into a video, and the right way seems to use a AVAssetWriter with a AVAssetWriterInputPixelBufferAdaptor, and it works well, but it leaks memory. When I convert the CGImage to a CVPixelBuffer, I call…
Reuben Crimp
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- copyPixelBufferForItemTime:itemTimeForDisplay: null value

The issue I have is when I compile my app with iOS9 sdk when my app try to get a CVPixelBufferRef from an AVPlayerItemVideoOutput with the - copyPixelBufferForItemTime:itemTimeForDisplay: function I get a null value from time to time when the video…
user1241006
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Bounding Box from VNDetectRectangleRequest is not correct size when used as child VC

I am trying to use VNDetectRectangleRequest from Apple's Vision framework to automatically grab a picture of a card. However when I convert the points to draw the rectangle, it is misshapen and does not follow the rectangle is it should. I have been…
user
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How to convert UIImage to CVPixelBufferRef using YUV color space?

I am doing video recording. I need to snapshoot a view to a UIImage, and then convert it to CVPixelBufferRef. And it work fine with RGBA color space. But the CVPixelBufferRef I need should be with YUV color space. Anyone have any ideas? Thanks. +…
guojing
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Reliable access and modify captured camera frames under SceneKit

I try to add a B&W filter to the camera images of an ARSCNView, then render colored AR objects over it. I'am almost there with the following code added to the beginning of - (void)renderer:(id)aRenderer…
diviaki
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