标签: pbjvision

目标是使用Swift在设备上捕获全屏视频.在下面的代码中,视频捕获似乎全屏发生(录制相机预览时使用全屏),但视频的渲染以不同的分辨率发生.特别是对于5S,看起来捕获发生在320x568但渲染发生在320x480.

如何捕获和呈现全屏视频？

视频捕获代码:

private func initPBJVision() {
    // Store PBJVision in var for convenience
    let vision = PBJVision.sharedInstance()

    // Configure PBJVision
    vision.delegate = self
    vision.cameraMode = PBJCameraMode.Video
    vision.cameraOrientation = PBJCameraOrientation.Portrait
    vision.focusMode = PBJFocusMode.ContinuousAutoFocus
    vision.outputFormat = PBJOutputFormat.Preset
    vision.cameraDevice = PBJCameraDevice.Back

    // Let taps start/pause recording
    let tapHandler = UITapGestureRecognizer(target: self, action: "doTap:")
    view.addGestureRecognizer(tapHandler)

    // Log status
    print("Configured PBJVision")
}


private func startCameraPreview() {
    // Store PBJVision in var for convenience
    let vision = PBJVision.sharedInstance()

    // Connect PBJVision …

我们在iOS上捕捉视频的同时使用setPreferredVideoStabilizationMode:AVCaptureVideoStabilizationModeAuto,但视频仍然有时出来模糊在开始和结束时(中间细,虽然),因为我们抢第一帧作为静止图像(以这是很成问题无需切换相机模式即可启用视频和照片功能).

将设备平放在桌面上可以消除所有模糊现象,因此整个视频都非常清晰.这表明它与视频稳定有关,但还有其他属性可以设置吗？

锁定焦点模式是否重要？

还有其他疑难解答吗？

以下是PBJVision的视频捕捉功能,我们使用它:

- (void)startVideoCapture
{
    if (![self _canSessionCaptureWithOutput:_currentOutput] || _cameraMode != PBJCameraModeVideo) {
        [self _failVideoCaptureWithErrorCode:PBJVisionErrorSessionFailed];
        DLog(@"session is not setup properly for capture");
        return;
    }

    DLog(@"starting video capture");

    [self _enqueueBlockOnCaptureVideoQueue:^{

        if (_flags.recording || _flags.paused)
            return;

        NSString *guid = [[NSUUID new] UUIDString];
        NSString *outputFile = [NSString stringWithFormat:@"video_%@.mp4", guid];

        if ([_delegate respondsToSelector:@selector(vision:willStartVideoCaptureToFile:)]) {
            outputFile = [_delegate vision:self willStartVideoCaptureToFile:outputFile];

            if (!outputFile) {
                [self _failVideoCaptureWithErrorCode:PBJVisionErrorBadOutputFile];
                return;
            }
        }

        NSString *outputDirectory = (_captureDirectory == nil ? NSTemporaryDirectory() : _captureDirectory); …