ios – CVMetalTextureCacheCreateTextureFromImage始终返回null

我正试图通过MetalKit渲染I420(ycbcr规划器)

大多数例子都是使用来自Camera的CMSampleBuffer,

但我的目标是使用给定的I420字节.

我做这样的事情：

let data = NSMutableData(contentsOfURL: NSBundle.mainBundle().URLForResource("yuv_640_360",withExtension: "yuv")!)

// Cache for Y

CVMetalTextureCacheCreate(kcfAllocatorDefault,nil,self.device!,&videoTextureCache)

var pixelBuffer: CVPixelBuffer?

CVPixelBufferCreateWithBytes(kcfAllocatorDefault,Int(size.width),Int(size.height),kCVPixelFormatType_420YpCbCr8BiPlanarVideoRange,data.mutableBytes,[
    "kCVPixelBufferMetalCompatibilityKey": true,"kCVPixelBufferOpenGLCompatibilityKey": true,"kCVPixelBufferIOSurfacePropertiesKey": []
    ],&pixelBuffer)

// Y texture

var yTextureRef : Unmanaged<CVMetalTexture>?

let yWidth = CVPixelBufferGetWidthOfPlane(pixelBuffer,0)

let yHeight = CVPixelBufferGetHeightOfPlane(pixelBuffer,0)

let result = CVMetalTextureCacheCreateTextureFromImage(kcfAllocatorDefault,(videoTextureCache?.takeUnretainedValue())!,pixelBuffer,MTLPixelFormat.R8Unorm,yWidth,yHeight,&yTextureRef);

基本上代码与其他示例几乎相同,但我自己创建自己的CVPixelBuffer.

我创建CVPixelBuffer和CVMetalTexture时没有出错,

但它总是为yTexture返回null.

如何创建正确的CVPixelBuffer并使用它进行渲染？

解决方法

问题解决了.

iosurface很重要,如果你通过CVPixelBufferCreateWithBytes或CVPixelBufferCreateWithPlanarBytes创建CVPixelBuffer,我发现iosurface总是为null.

一旦你使用了iosurface为null的CVPixelBuffer,那么MetalTexture总是为空.

应该做这样的事情：

let result = CVPixelBufferCreate(kcfAllocatorDefault,width,height,kCVPixelFormatType_420YpCbCr8Planar,[
    String(kCVPixelBufferIOSurfacePropertiesKey): [
        "IOSurfaceOpenGLESFBOCompatibility": true,"IOSurfaceOpenGLESTextureCompatibility": true,"IOSurfaceCoreAnimationCompatibility": true,]
    ],&self.pixelBuffer)

CVPixelBufferLockBaseAddress(self.pixelBuffer!,0)

for index in 0...2 {

    memcpy(CVPixelBufferGetBaseAddressOfPlane(self.pixelBuffer!,index),planesAddress[index],planesWidth[index] * planesHeight[index])

}

CVPixelBufferUnlockBaseAddress(self.pixelBuffer!,0)