iPhone 4(S) vs iPad2 computer vision performance problems

asked 2014-05-12 06:11:47 -0600

bertus gravatar image

We have this project using OpenCV and at first we developed for iPad2.

Everything ran smooth and an computer vision object recognition iteration was taking a little under 1 second.

So far so good. Now we are testing the app for iPhone on both 4 and 4S. Of course we did our research as the results were stating the iPhone4S performance was almost as fast as the iPad2.

The results of the iPhone 4 are terrible, one iteration takes 15 seconds. In the iPhone 4S on iteration takes 8 seconds.

So with our algorithms: iPhone4 is 15x slower than an iPad2 iPhone4S is 7-8x slower than an iPad2

Does anybody know if this is true? Is there something the iPhone is doing differently than the iPad2? Isn't the processor of the same type?

Anybody who can point us in the right direction?

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Comments

Hey,

I'm having similar issues. We have a code running on Android and iOS and it works fine everywhere except the iPhone 4 and 4s. As far as I could track down the issue the very slow part is the parallel_for loop used in various methods just as the very common cvtColor method.

Do you have any findings on this issue already? Could you resolve it?

ThomasB gravatar imageThomasB ( 2014-07-22 08:36:28 -0600 )edit

Hello, I have this problem too, except that for me iPhone 4S performance is fine. The iPhone 4 performance is 10x slower. I am wondering if it's a library version issue, tools, or something else, because I have seen good performance on iPhone 4 previously (a year ago). Thanks for any hints.

Buddhisthead gravatar imageBuddhisthead ( 2014-11-14 15:27:29 -0600 )edit