MovieOutput with Camera resulted in black pixels

[barbayrak]

Hi there ,

I want to migrate GPUImage2 to GPUImage3 but when i run a test that simply captures from Camera and writes to a file i weirdly got black pixels randomly in my output . I am sharing my test viewcontroller and result video's one frame (black pixels appears especially on top of the record video). I also test this code on Iphone X (13.5) and Iphone 8 (12.1) . Iphone X a lot less black pixels compared to Iphone 8

When i run the same code on GPUImage2 everything is fine

import UIKit
import AVFoundation
import AVKit
import GPUImage

class ViewController: UIViewController {

    @IBOutlet var renderView: RenderView!

    var camera : Camera!
    var effectMovie : MovieInput!
    var movieOutput : MovieOutput!

    var isRecording = false
    var recordUrl = ""

    override func viewDidLoad() {
        super.viewDidLoad()
        setupViews()
    }

    func setupViews(){

        do {
             camera = try Camera(sessionPreset: .hd1280x720)
             camera --> renderView
             camera.startCapture()
         } catch {
             fatalError("Could not initialize rendering pipeline: \(error)")
         }

    }

    @IBAction func recordTapped(_ sender: Any) {
        if (!isRecording) {
            do {
                self.isRecording = true

                let documentDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first!
                let filePath = documentDirectory.path + "/" + "recorded" + ".mov"
                self.recordUrl = filePath
                let fileURL = URL(fileURLWithPath: filePath)
                do {
                    try FileManager.default.removeItem(at:fileURL)
                } catch {

                }

                movieOutput = try MovieOutput(URL:fileURL, size:Size(width:720.0, height:1280.0), liveVideo:true)

                camera --> movieOutput

                movieOutput!.startRecording()

            } catch {
                fatalError("Couldn't initialize movie, error: \(error)")
            }
        } else {
            movieOutput?.finishRecording{
                self.isRecording = false
                self.movieOutput = nil
                DispatchQueue.main.async {
                    self.performSegue(withIdentifier: "test", sender: nil)
                }

            }
        }
    }

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if(segue.identifier == "test"){
            let dest = segue.destination as! TestVideoViewController
            dest.path = recordUrl
        }
    }
}

[luoser]

do you have an audioEncodingTarget configured in the GPU Camera? i encountered this issue as well when trying to enable the audio track (by copying over bits from GPUImage2), but the black pixels went away when removing the audio logic. reference: https://github.com/BradLarson/GPUImage/issues/1255

[eliot1019]

@luoser I also readded some of the audioEncodingTarget logic from GPUImage2 so that my video would have audio. I'm getting black squares on the top parts of my video sometimes. Which logic did you end up removing?

The reference you posted seems to tell you to remove the first and last frame from the video which isn't necessary for me as only parts of the video have these black squares.

[luoser]

@eliot1019 you are correct, that reference mentions frames rather than the pixelation issue that we are experiencing, i had followed some comments from there to see if it would help. i actually haven't been able to consistently resolve this issue so am still working on it, unfortunately deprecating back to GPUImage2 doesn't seem to be a viable option since OpenGL is deprecated and my project targets 13+ :/

[Darwel]

In MovieOutput.swift change this

func renderIntoPixelBuffer(_ pixelBuffer:CVPixelBuffer, texture:Texture) {
        guard let pixelBufferBytes = CVPixelBufferGetBaseAddress(pixelBuffer) else {
            print("Could not get buffer bytes")
            return
        }

        let bytesPerRow = CVPixelBufferGetBytesPerRow(pixelBuffer)

        let outputTexture:Texture

        if (Int(round(self.size.width)) != texture.texture.width) && (Int(round(self.size.height)) != texture.texture.height) {
            let commandBuffer = sharedMetalRenderingDevice.commandQueue.makeCommandBuffer()

            outputTexture = Texture(device:sharedMetalRenderingDevice.device, orientation: .portrait, width: Int(round(self.size.width)), height: Int(round(self.size.height)), timingStyle: texture.timingStyle)

            commandBuffer?.renderQuad(pipelineState: renderPipelineState, inputTextures: [0:texture], outputTexture: outputTexture)
            commandBuffer?.commit()
            commandBuffer?.waitUntilCompleted()
        } else {
            outputTexture = texture
        }

        let region = MTLRegionMake2D(0, 0, outputTexture.texture.width, outputTexture.texture.height)

        outputTexture.texture.getBytes(pixelBufferBytes, bytesPerRow: bytesPerRow, from: region, mipmapLevel: 0)
    }

to this

func renderIntoPixelBuffer(_ pixelBuffer:CVPixelBuffer, texture:Texture) {
        guard let pixelBufferBytes = CVPixelBufferGetBaseAddress(pixelBuffer) else {
            print("Could not get buffer bytes")
            return
        }

        let bytesPerRow = CVPixelBufferGetBytesPerRow(pixelBuffer)

        let outputTexture:Texture

        let commandBuffer = sharedMetalRenderingDevice.commandQueue.makeCommandBuffer()
        outputTexture = Texture(device:sharedMetalRenderingDevice.device,
                                orientation: .portrait,
                                width: Int(round(self.size.width)),
                                height: Int(round(self.size.height)),
                                timingStyle: texture.timingStyle)

        commandBuffer?.renderQuad(pipelineState: renderPipelineState, inputTextures: [0:texture], outputTexture: outputTexture)
        commandBuffer?.commit()
        commandBuffer?.waitUntilCompleted()

        let region = MTLRegionMake2D(0, 0, outputTexture.texture.width, outputTexture.texture.height)

        outputTexture.texture.getBytes(pixelBufferBytes, bytesPerRow: bytesPerRow, from: region, mipmapLevel: 0)
    }

will fix. It should wait until rendering is complete.

[bhadresh13]

Actual video is green

remove green color using ChromaKeyBlend but its give black background I want to remove that black background because I want to play on AR how its possible ?