Memory Leak with Picture Control

[Nadav_Chernin]

Hi all

There is bug with Picture Control

When you insert you picture data in loop into the shift register, memory leak

Can somebody to prevent this bug?

Run attached example and look at Task Manager

[DavidJCrawford]

Its expected behaviour in your implementation. You keep appending the image which means the picture continues to grow. Thats why you have a memory leak.

David

[Ben]

I believe David properly called the cause of this memory consumption.

In reply # 52 of thsi thread,

http://forums.ni.com/ni/board/message?board.id=BreakPoint&message.id=5&jump=true

I posted an example that inserts 130 FP object images in a picture and moves them around (it is a random walk where each object is assigned a letter and the program terminates when all of the letters required to spell out "Hello World" wander into the trap at the bottom.)

A snippet of the code follows.

A) Start with a blank picture

B) Inster all of the images

C) show the updated image.

Other links to LV Picture control examples can be found in this thread.

http://forums.ni.com/ni/board/message?board.id=BreakPoint&message.id=14&jump=true

Ben

Message Edited by Ben on 01-14-2007 08:58 AM

[altenbach]

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@nadav Chernin wrote:

Can somebody to prevent this bug?

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Just replace the shift register with a plain tunnel and place the "get image" node inside the loop. 🙂 (This is the solution if the string might change during run and you want to see the current image.)

.... Of course since the "get image" node is currently outside the loop, it will run exactly once and nothing will ever change inside the loop. You might as well delete the loop entirely. Right?

[Nadav_Chernin]

Hi, David

I don't think that i just append new picture to old picture as to concatinate 2 strings. I think that LV implement it as replace area of old picture by new picture.

Look attached example that continue to append picture but memory don't leak

[rolfk]

Except that your last code does absolutly nothing that is useful and couldn't be done without loop and shiftregister at all and indeed does not leak any moeory there is a very big difference to your original VI. In there you do append a new picure each time to the existing picture. You do not see any effect because they are all the same and the Picture control rendering is way to fast to let you see that it actually draws the same picture one more time after each loop iteration.

Rolf Kalbermatter

Message Edited by rolfk on 01-15-2007 11:32 AM

[DavidJCrawford]

If you need to be convinced then take a look inside the Draw Flattened Pixmap.

David

Message Edited by David Crawford on 01-15-2007 10:42 AM

[Ben]

Nadav,

Inside your loop (of your original example) branch the wire coming for the shift-register to a "flatten to string" then get the sring length returned and display it on your FP.

You will see that the amount of data in the SR grows with each interation.

Ben