应用过滤器时GPUImageMovie暂停

Question

我正在使用Brad Larson的伟大库GPUImage来处理我的应用程序.目前我遇到了一个问题.我的应用程序捕获10秒视频,之后允许filter应用.在申请filters时GPUImageMovie,我无法暂停播放并应用新filter视频,以便视频可以连续播放而无需从头开始播放.

我在这里看到了一个开放的github问题.如果有人遇到类似问题并找到解决方案,请发布您的答案.提前致谢.

Answer 1

最后我在经过太多搜索后尝试修复此问题.我们需要使用AVPlayerItem而不是URL来启动GPUImageMovie.我从这里得到了这个有价值的线索.

我发布了我目前在我的应用程序中使用的代码,它正在按预期工作.但iPod 6.1存在性能问题,我正在努力改进它.

设置GPUImageMovie的初始方法,

- (void)setupVideo
{
    playerItem = [[AVPlayerItem alloc]initWithURL:self.recordSession.outputUrl];
    player = [AVPlayer playerWithPlayerItem:playerItem];

    movieFile = [[GPUImageMovie alloc] initWithPlayerItem:playerItem];

    movieFile.runBenchmark = YES;
    movieFile.playAtActualSpeed = YES;
    [self.view sendSubviewToBack:self.videoView];

    [movieFile addTarget:filter];
    [filter addTarget:self.videoView];

    [movieFile startProcessing];
    movieRunning = YES;

    dispatch_async(dispatch_get_main_queue(), ^{
        self.playButton.hidden = YES;
    });

    player.rate = 1.0;
}

当用户单击过滤器按钮时,将调用此方法.

- (void)filterClicked:(UIButton *)button
{
    // Set paused time. If player reaches end of the video, set pausedTime to 0.
    if (CMTIME_COMPARE_INLINE(pausedTime, !=,  player.currentItem.asset.duration)) {
        pausedTime = player.currentTime;
    } else {
        pausedTime = CMTimeMake(0, 600.0);
    }
    [self.videoView setBackgroundColor:[UIColor clearColor]];

    [movieFile cancelProcessing];

    switch (button.tag)
    {
    case 0:
        filter = [[GPUImageFilter alloc] init];
        break;
    case 1:
        filter = [[GPUImageColorInvertFilter alloc] init];
        break;
    case 2:
        filter = [[GPUImageEmbossFilter alloc] init];
        break;
    case 3:
        filter = [[GPUImageGrayscaleFilter alloc] init];
        break;
    default:
        filter = [[GPUImageFilter alloc] init];
        break;
    }

    [self filterVideo];

}

生成过滤器后,在此方法中处理视频播放恢复.

- (void)filterVideo {

    // AVPlayerItem is initialized with required url

    playerItem = [[AVPlayerItem alloc]initWithURL:self.outputUrl]; 
    [player replaceCurrentItemWithPlayerItem:playerItem];

    //GPUImageMovie is initialized with AVPlayerItem

    movieFile = [[GPUImageMovie alloc] initWithPlayerItem:playerItem];

    movieFile.runBenchmark = YES;
    movieFile.playAtActualSpeed = YES;

    // Adding targets for movieFile and filter

    [movieFile addTarget:filter];
    [filter addTarget:self.videoView]; // self.videoView is my GPUImageView

    [movieFile startProcessing];
    movieRunning = YES;

    dispatch_async(dispatch_get_main_queue(), ^{
        self.playButton.hidden = YES;
    });

    // Player rate is set to 0 means player is paused

    [player setRate:0.0];

    // Seeking to the point where video was paused

     if (CMTIME_COMPARE_INLINE(pausedTime, !=, player.currentItem.asset.duration)) {
        [player seekToTime:pausedTime];
    }
    [player play];
}