Question

我使用GPUImage在我的视频上添加叠加层。在预览中它看起来很棒，但我怎样才能将我的视频写入文件？我使用GPUMovieWriter，但我找不到这个文件，我甚至不知道它是否有效。这是我的代码：

-(void)setUpCameraWithPosition:(bool)switchToFrontCamera
{
    if(videoCamera != nil)
    {
        [videoCamera stopCameraCapture];
    }

    if(switchToFrontCamera) {
        videoCamera = [[GPUImageVideoCamera alloc] initWithSessionPreset:AVCaptureSessionPreset640x480 cameraPosition:AVCaptureDevicePositionFront];
    }
    else {
        videoCamera = [[GPUImageVideoCamera alloc] initWithSessionPreset:AVCaptureSessionPreset640x480 cameraPosition:AVCaptureDevicePositionBack];
    }

    videoCamera.outputImageOrientation = UIInterfaceOrientationPortrait;
    videoCamera.horizontallyMirrorFrontFacingCamera = NO;
    videoCamera.horizontallyMirrorRearFacingCamera = NO;

    filter = [GPUImageiOSBlurFilter new];
    filter.blurRadiusInPixels = 3.0;

    GPUImageAlphaBlendFilter *blendFilter = [[GPUImageAlphaBlendFilter alloc] init];
    blendFilter.mix = 1.0;

    NSDate *startTime = [NSDate date];

    UILabel *timeLabel = [[UILabel alloc] initWithFrame:CGRectMake(0.0, 0.0, 240.0f, 320.0f)];
    timeLabel.font = [UIFont systemFontOfSize:17.0f];
    timeLabel.text = @"Time: 0.0 s";
    timeLabel.textAlignment = UITextAlignmentCenter;
    timeLabel.backgroundColor = [UIColor clearColor];
    timeLabel.textColor = [UIColor whiteColor];

    [videoCamera addTarget:filter];
    GPUImageView *filterView = (GPUImageView *)self.preview;
    filterView.fillMode = kGPUImageFillModePreserveAspectRatioAndFill;

    NSString *pathToMovie = [NSHomeDirectory() stringByAppendingPathComponent:@"file.mov"];
    unlink([pathToMovie UTF8String]); // If a file already exists, AVAssetWriter won't let you record new frames, so delete the old movie
    NSURL *movieURL = [NSURL fileURLWithPath:pathToMovie];
    movieWriter = [[GPUImageMovieWriter alloc] initWithMovieURL:movieURL size:CGSizeMake(480.0, 640.0)];
    movieWriter.encodingLiveVideo = YES;

    [filter addTarget:movieWriter];

    uiElementInput = [[GPUImageUIElement alloc] initWithView:timeLabel];
    [filter addTarget:blendFilter];
    [uiElementInput addTarget:blendFilter];

    [blendFilter addTarget:filterView];

    __unsafe_unretained GPUImageUIElement *weakUIElementInput = uiElementInput;

    [filter setFrameProcessingCompletionBlock:^(GPUImageOutput * filter, CMTime frameTime){
        timeLabel.text = [NSString stringWithFormat:@"Time: %f s", -[startTime timeIntervalSinceNow]];
        [weakUIElementInput update];
    }];

    [videoCamera startCameraCapture];
}

如何将我的电影写入AssetsLibrary？

Answer 1

我认为通过叠加你的意思是你想用UIElement作为叠加来写视频吗？

在这种情况下，您可能希望通过＆＃34; blendFilter＆＃34;写出来。而不是＆＃34;过滤＆＃34;

删除此行

[filter addTarget:movieWriter];

并在初始化blendFilter

后添加它

[blendFilter addTarget:movieWriter];
[blendFilter addTarget:filterView];

你对movieWriter的初始化似乎没问题，我唯一的区别就是我使用＆＃34; .m4v＆＃34;作为视频格式。这是Apple的标准格式。

视频应保存到应用程序主文件夹。使用＆＃34; Orginizer＆＃34; （＆＃34; CMD + SHIFT + 2＆＃34;）在XCode中查看应用程序文件夹，视频应该在＃34; Documents＆＃34;。

ios保存GPUImage视频

1 个答案: