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=[[GPUImageMoviealloc]initWithURL:assetURL];if([filterTypeisEqualToString:@"BigApple1"]){self.lookupImageSource=[[GPUImagePicturealloc]initWithImage:[UIImageimageNamed:@"BigApple1.png"]];[self.lookupImageSourcep