Halide (programming language)

Halide

Designed by	Jonathan Ragan-Kelley and Andrew Adams
Developer	MIT, (with help from Stanford and Adobe)
First appeared	2012
OS	Mac OS X (10.6 through 10.8), mainstream Linux distributions
Website	http://halide-lang.org/

Halide is a computer programming language designed to make it easier to write image processing code that a compiler can efficiently and automatically parallelize onto a Graphical Processing Unit (GPU) pipeline.

Sample source code

Func blur_3x3(Func input) {
  Func blur_x, blur_y;
  Var x, y, xi, yi;

  // The algorithm - no storage or order
  blur_x(x, y) = (input(x-1, y) + input(x, y) + input(x+1, y))/3;
  blur_y(x, y) = (blur_x(x, y-1) + blur_x(x, y) + blur_x(x, y+1))/3;

  // The schedule - defines order, locality; implies storage
  blur_y.tile(x, y, xi, yi, 256, 32)
        .vectorize(xi, 8).parallel(y);
  blur_x.compute_at(blur_y, x).vectorize(x, 8);

  return blur_y;
}

External links

• http://halide-lang.org/
• Decoupling Algorithms from Schedules for Easy Optimization of Image Processing Pipelines
• Template:PDFlink