What shows better performance? Playing a movie clip, or animating an image sequence with UIImageView?

Question

Specs: about 320 x 270 px, 5 seconds. I don't know exactly how many images needed for a fluid animation, but let's assume 30.

What would be the best way to playback this? As a movie file in some kind of quicktime view (if available), or as an animated image sequence with UIImageView? I'm not sure but I believe loading 30 images per second is nearby impossible on the ipod touch. Any idea?

Answer 1

In general, a movie will have applied some compression and possibly even used a lossy compression. This means the processor would need to work harder but it has a lot less memory to read. The CPU is a fast resource. Compared to the CPU, memory is slow. Thus a compressed movie would (logically) have the better performance.

In practice, it could depend on a lot of factors, although movies do tend to be better optimized for animations. With a slow CPU and extremely fast memory, a multi-image animation might just be faster. Also, it depends on how you store those many images. But in 99% of all situations, movies will have better performance.

Answer 2

Why would you not want to use a video file? If you don't have very specific reasons, I would recommend just using the standard video playback functions provided by Apple.

This gives you several advantages:

• Even if your proposed method would run fluidly, it certainly wouldn't be as well optimised for the graphics chip and therefore use up more battery
• It's very easy to implement, whereas your idea would be rather complicated, and you'd spend a lot of time on a probably less important part of your app.
• It's won't introduce any new bugs and is most likely a lot better tested than your custom solution.

Check out this to get started:

http://developer.apple.com/iphone/library/navigation/index.html?section=Topics&topic=Audio%20%26amp%3B%20Video

Answer 3

Well, I guess it depends.... if it supposed to be static, than a movie is the most appropriate way... it's hardware accelerated, and easy to write the code for using it. If you plan to modify the animation, and reuse it, you could load and modify images, or load a bunch of them in succession, but I imagine it's quite coding overkill for the task.