ios - 如何检测 GPUImageMovie 何时完成处理

Question

有没有办法检测 GPUImageMovie 何时完成处理？目前我不想保存电影，所以没有带有完成 block 的 GPUImageMovieWriter。

self.movieFile = [[GPUImageMovie alloc] initWithURL:assetURL];

if([filterType isEqualToString:@"BigApple 1"]){

    self.lookupImageSource = [[GPUImagePicture alloc] initWithImage:[UIImage imageNamed:@"BigApple1.png"]];
    [self.lookupImageSource processImage];
    [self.lookupImageSource useNextFrameForImageCapture];

    filter = [[GPUImageLookupFilter alloc] init];
    [lookupImageSource addTarget:filter atTextureLocation:1];

}

[movieFile addTarget:filter];

[filter addTarget:videoWindow];

[self.imageThumbnail removeFromSuperview];

[movieFile startProcessing];

Answer 1

通过使用计时器然后检查 GPUImageMovie 上的进度值解决了这个问题。

self.sampleTimer = [NSTimer scheduledTimerWithTimeInterval:0.1f
                                                  target:self
                                                selector:@selector(retrievingSampleProgress)
                                                userInfo:nil
                                                 repeats:YES];

- (void)retrievingSampleProgress {

NSLog(@"Sample Complete:%f",self.movieFile.progress);

if(self.movieFile.progress == 1){
    [self.sampleTimer invalidate];
    self.viewingSample = 0;
}else {
    self.viewingSample = 1;
}