Question

我在iOS上尝试图像处理算法。我有一个包含图像test_frame1 ... test_frame100（等等）的资产目录，我会对其进行处理。

除此之外，我需要按顺序显示图像，就好像它们是视频帧一样。

我想到的第一件事是在延迟几毫秒之后依次更改UIImage的图像。我正在异步这样做。这是代码：

    let imageShowQueue = dispatch_queue_create("com.grigoryptashko.ImageShowQueue",
        DISPATCH_QUEUE_SERIAL)
    let frameShowDelay = Int64(0.2 * Double(NSEC_PER_SEC)) // show images with 200 ms delay, but it doesn't actually work this way
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0)) {
        var dTime = dispatch_time(DISPATCH_TIME_NOW, frameShowDelay)
        for i in 1...1000 {
            dispatch_after(dTime, self.imageShowQueue) {
                dispatch_async(dispatch_get_main_queue()) {
                    NSLog("test_frame\((i % 100) + 1)")
                    self.imgView.image = UIImage(named: "test_frame\((i % 100) + 1)")
                    self.imgView.setNeedsDisplay()
                }
            }

            dTime = dispatch_time(dTime, frameShowDelay)
        }
    }

它实际上有效，但FPS很快变得太低，比如1 FPS甚至更慢。还有其他方法可以达到这个目的吗？

也许，有一些我不知道的方式。例如，最近我了解了Accelerate框架和Apple Metal。蚂蚁其他想法？

Answer 1

听起来你想要一个基于图像的动画。这是你要做的：

在viewDidLoad

中

self.<name of the UIImageView you want to animate>.animationImages = [[NSArray alloc] initWithObjects: [UIImage imageNamed:@"Image Name"],
                                     [UIImage imageNamed:@"Image Name"],
                                     [UIImage imageNamed:@"Image Name"],
                                     [UIImage imageNamed:@"Image Name"],
                                     [UIImage imageNamed:@"Image Name"],
                                     [UIImage imageNamed:@"Image Name"],
                                     [UIImage imageNamed:@"Image Name"],
                                     [UIImage imageNamed:@"Image Name"],nil];
                      /* Do this until you have all the images in the array */
self.<name of the UIImageView you want to animate>.animationDuration = 1.0f;
self.<name of the UIImageView you want to animate>.animationRepeatCount = 1;

如果您想要动画启动，请使用[<name of the UIImageView you want to animate> startAnimating];。 animationDuration和animationRepeatCount的数字可以更改为您希望它们的值。 Here是Apple Docs的链接。

对于Swift开发：

<name of the UIImageView you want to animate>.animationImages = [
                                         UIImage(named: "Image Name")!,
                                         UIImage(named: "Image Name")!,
                                         UIImage(named: "Image Name")!,
                                         UIImage(named: "Image Name")!,
                                         UIImage(named: "Image Name")!,
                                         UIImage(named: "Image Name")!,
                                         UIImage(named: "Image Name")!,
                                         UIImage(named: "Image Name")!
                                       ]
                          /* Do this until you have all the images in the array */
<name of the UIImageView you want to animate>.animationDuration = 1.0
<name of the UIImageView you want to animate>.animationRepeatCount = 1

Answer 2

通过在animatedImageNamed:上使用UIImage，可以更直接地实现此目的。看看这个：

UIImage *animatingImage = [UIImage animatedImageNamed:@"test_frame_" duration:1.0];
UIImageView *anImageView = [[UIImageView alloc] initWithImage:animatingImage];

Answer 3

尝试这个，更改数组中的图像并编译项目，在此部分设置时间间隔

animationImageView.animationDuration = 0.5;

http://www.appcoda.com/ios-programming-animation-uiimageview/

像视频一样显示一系列图像？

3 个答案: