IOS 每0.2秒获得一个UIImage对象 怎么把这些对象转换为视频显示

这个数据是从摄像头过来的 uuimage都是不同的对象 怎么能把这些uiimage变成视频展示出来呢 如果不断地更新UIImageVIew的image的话 会内存不足导致程序闪退

dispatch_sync(dispatch_get_main_queue(), ^{
CGSize imageSize = [UIScreen mainScreen].bounds.size;
UIGraphicsBeginImageContext(imageSize);
[targetView.layer renderInContext:UIGraphicsGetCurrentContext()];
image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
if (buffer == NULL){
buffer = [self pixelBufferFromCGImage:[image CGImage] size:size];
}

    if (buffer)
    {
            CFAbsoluteTime interval = (CFAbsoluteTimeGetCurrent() - startTime) * 1000;
            CMTime currentSampleTime = CMTimeMake((int)interval, 1000);

            if(![adaptor appendPixelBuffer:buffer withPresentationTime:currentSampleTime]){
                    printf("FAIL");
            }

            ++frame;
            printf("removing buffer……");
            image = nil;
            CFRelease(buffer);
            //                        [videoWriterInput markCurrentPassAsFinished];
            //                        [videoWriter finishWritingWithCompletionHandler:^{
            //                            CGImageRelease(image.CGImage);
            //                        }];
            //
            buffer = NULL;
    }

});
要在一个同步队列里面做uiimage创建和压帧操作，不然uiimage对象是不会被释放掉的。