Problem modifying bitmap returned from ImageReady()

[concept85]

Hello,
I want to modify the bitmap returned from ImageReady() used when I make a capture from the camera.
The problem that I tried a direct modification to the bitmap, on the compilation everything is good, but on the device the application abort.
Even I tried to make a copy of the bitmap returned to another bitmap and tried to access it, I had the same problem! Can anyone suggest me a solution ? I’m programming on a S60, it’s nokia N70.
Thank you

[wizard_hu_]

What do you mean on "direct modification"? If you are trying to modify a bitmap using DataAddress, remember to LockHeap prior to getting the address, and UnlockHeap after modification.

[concept85]

i already lock and unlock the heap after the modification, still i can't modify the bitmap.
i mean by direct modification:
in the method Imageready(CFbsBitmap* aBitmap,HBufC8* aData,TInt aError)
i copy the reference of aBitmap to iBitmap,(i work with ibitmap) then i lock the heap, i modify the bitmap by accessing the dataaddress to modify and then i unlock the heap

when i modify, the application crash!