图形处理器Image2音频问题

Question

在使用GPUImage2过滤视频时，我无法获得音频。请帮帮我。提前谢谢。

movie = try MovieInput(url:url, playAtActualSpeed:false)

let documentDirectory = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first! as String
let uuid1 = CFUUIDCreateString(nil, CFUUIDCreate(nil)) as NSString?

localPath = (documentDirectory as NSString).appendingPathComponent(String(format: "%@.mp4", uuid1!)) as NSString!

print("Filtered Video: %@", localPath)
let fileURL = URL.init(fileURLWithPath: localPath as String)

do {
    try FileManager.default.removeItem(at: fileURL)
} catch {
}

movieOutput = try MovieOutput(URL:fileURL, size: Size(width: 720, height: 1280), liveVideo: true)

Filter4 = ColorMatrixFilter()
Filter4.overriddenOutputRotation = Rotation.rotateClockwiseAndFlipVertically

movie --> Filter4 --> renderView

movie.runBenchmark = true
movie.start()

Filter4 --> movieOutput

movieOutput!.startRecording()

Answer 1

此功能未在GPUImage2框架中实现。正如您在MovieInput类源代码中看到的，它标记为TODO：

public init(asset:AVAsset, playAtActualSpeed:Bool = false, loop:Bool = false) throws {
    self.asset = asset
    self.playAtActualSpeed = playAtActualSpeed
    self.loop = loop
    self.yuvConversionShader = crashOnShaderCompileFailure("MovieInput"){try sharedImageProcessingContext.programForVertexShader(defaultVertexShaderForInputs(2), fragmentShader:YUVConversionFullRangeFragmentShader)}

    assetReader = try AVAssetReader(asset:self.asset)

    let outputSettings:[String:AnyObject] = [(kCVPixelBufferPixelFormatTypeKey as String):NSNumber(value:Int32(kCVPixelFormatType_420YpCbCr8BiPlanarFullRange))]
    let readerVideoTrackOutput = AVAssetReaderTrackOutput(track:self.asset.tracks(withMediaType: AVMediaTypeVideo)[0], outputSettings:outputSettings)
    readerVideoTrackOutput.alwaysCopiesSampleData = false
    assetReader.add(readerVideoTrackOutput)
    // TODO: Audio here
}

您需要检查Camera类和audioEncodingTarget属性。以下是SimpleVideoRecorder示例中的代码片段：

movieOutput = try MovieOutput(URL:fileURL, size:Size(width:480, height:640), liveVideo:true)
camera.audioEncodingTarget = movieOutput

正如您所看到的，您应该设置音频目标，只有在此之后，MovieOutput类才会工作。但同样，MovieInput类不支持AudioEncodingTarget。