Parallel Programming

Parallel Programming#

The Power of Parallelism#

Given a nXm gray level image, generate a binary image so that the value if any pixel is 1 if and only if the gray level of the original pixel is great than a given threshold.

Algorithm?

Time?

Can we improve?

GPU – Graphics Processing Unit#

CPU Over the Years#

  • Smaller

  • Faster

  • Less power

  • More on a chip

Clock Frequency Over the Years#

Improvement stopped because:

  • Heat

  • Need a lot of power

Solution:

CPU is good at:#

Blurring Images in Parallel#

  • Use an average filter to blur a gray level image

  • Note the synchronization

Tells the compiler that this is a function that runs on GPU

Image 1 Image 2

Be careful of race conditions!

Not a stencil because not working on each cell

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