我需要在实时视频上应用过滤器，我正在尝试在 Metal 中执行此操作。
但是在将过滤器编码为目标过滤器后，我遇到了将 MTLTexture 转换为 CVPixelBuffer 的问题。参考（https://github.com/oklyc/MetalCameraSample-master-2）
这是我的代码。
if let pixelBuffer = pixelBuffer {
CVPixelBufferLockBaseAddress(pixelBuffer, CVPixelBufferLockFlags.init(rawValue: 0))
let region = MTLRegionMake2D(0, 0, Int(currentDrawable.layer.drawableSize.width), Int(currentDrawable.layer.drawableSize.height))
let bytesPerPixel = 4;
let bytesPerRow = CGFloat(bytesPerPixel) * currentDrawable.layer.drawableSize.width
let tempBuffer = CVPixelBufferGetBaseAddress(pixelBuffer)
destinationTexture.getBytes(tempBuffer!, bytesPerRow: Int(bytesPerRow), from: region1, mipmapLevel: 0)
let image = self.imageFromCVPixelBuffer(buffer: pixelBuffer)
CVPixelBufferUnlockBaseAddress(pixelBuffer, CVPixelBufferLockFlags.init(rawValue: 0))
}
方法 imageFromCVPixelBuffer 看起来像这样。
func imageFromCVPixelBuffer(buffer: CVPixelBuffer) -> UIImage {
let ciimage = CIImage(cvPixelBuffer: buffer)
let context = CIContext(options: nil)
let cgimgage = context.createCGImage(ciimage, from: CGRect(x: 0, y: 0, width: CVPixelBufferGetWidth(buffer), height: CVPixelBufferGetHeight(buffer)))
let uiimage = UIImage(cgImage: cgimgage!)
return uiimage
}
这是通过金属渲染图像的屏幕截图
这是将 MTLTexture 转换为 CVPixelBuffer 的同一图像的屏幕截图。
需要将 MTLtexture 转换为 CVPixelBuffer 以写入 AVAssetWriter 然后将其保存到库中。