Android JNI crashing on WVGA devices, but not HVGA

I'm doing some bimap manipulation, and my code works well on HVGA devices.

However, on WVGA, the JNI crashes with a seg fault.

What could the potential difference be? To be clear I am accessing bitmaps through the following pseudocode:

ret = AndroidBitmap_lockPixels(env, bmp, &dpixels) 
dpixels[pos] = // some color distortion 

Due to the sig fault I am guessing that I am accessing a bad memory address through dpixels. But I am not clear why there would be a difference between WVGA & HVGA devi开发者_如何学运维ces.