从CVPixelBuffer创建一个CMSampleBuffer

Question

我从Arsessiondelegate获得CVPixelBuffer：

func session(_ session: ARSession, didUpdate frame: ARFrame) {
    frame.capturedImage // CVPixelBufferRef
}

但是我的应用程序的另一部分（我无法更改）使用cmsamplebuffer。

cmsamplebuffer是cvpixelbuffer的容器。

为了创建一个cmsamplebuffer，我可以使用此功能：

func CMSampleBufferCreateReadyWithImageBuffer(_ allocator: CFAllocator?, 
                                            _ imageBuffer: CVImageBuffer, 
                                            _ formatDescription: CMVideoFormatDescription, 
                                            _ sampleTiming: UnsafePointer<CMSampleTimingInfo>, 
                                            _ sBufOut: UnsafeMutablePointer<CMSampleBuffer?>) -> OSStatus

对我来说唯一缺少的参数是sampleTiming-如何从cvpixelbuffer中提取该参数？

Answer 1

采样主要包含presentationTimeStamp，您可以通过以下代码来轻松创建它：

let scale = CMTimeScale(NSEC_PER_SEC)
let pts = CMTime(value: CMTimeValue(frame.timestamp * Double(scale)),
                 timescale: scale)
var timingInfo = CMSampleTimingInfo(duration: kCMTimeInvalid,
                                    presentationTimeStamp: pts,
                                    decodeTimeStamp: kCMTimeInvalid)