def get_bilateral_grid(input, r_sigma, s_sigma):
x = hl.Var('x')
y = hl.Var('y')
z = hl.Var('z')
c = hl.Var('c')
xi = hl.Var("xi")
yi = hl.Var("yi")
zi = hl.Var("zi")
# Add a boundary condition
clamped = hl.BoundaryConditions.repeat_edge(input)
# Construct the bilateral grid
r = hl.RDom([(0, s_sigma), (0, s_sigma)], 'r')
val = clamped[x * s_sigma + r.x - s_sigma // 2, y * s_sigma + r.y - s_sigma // 2]
val = hl.clamp(val, 0.0, 1.0)
zi = hl.i32(val / r_sigma + 0.5)
histogram = hl.Func('histogram')
histogram[x, y, z, c] = 0.0
histogram[x, y, zi, c] += hl.select(c == 0, val, 1.0)
# Blur the histogram using a five-tap filter
blurx, blury, blurz = hl.Func('blurx'), hl.Func('blury'), hl.Func('blurz')
blurz[x, y, z, c] = histogram[x, y, z-2, c] + histogram[x, y, z-1, c]*4 + histogram[x, y, z, c]*6 + histogram[x, y, z+1, c]*4 + histogram[x, y, z+2, c]
blurx[x, y, z, c] = blurz[x-2, y, z, c] + blurz[x-1, y, z, c]*4 + blurz[x, y, z, c]*6 + blurz[x+1, y, z, c]*4 + blurz[x+2, y, z, c]
blury[x, y, z, c] = blurx[x, y-2, z, c] + blurx[x, y-1, z, c]*4 + blurx[x, y, z, c]*6 + blurx[x, y+1, z, c]*4 + blurx[x, y+2, z, c]
# Take trilinear samples to compute the output
val = hl.clamp(clamped[x, y], 0.0, 1.0)
zv = val / r_sigma
zi = hl.i32(zv)
zf = zv - zi
xf = hl.f32(x % s_sigma) / s_sigma
yf = hl.f32(y % s_sigma) / s_sigma
xi = x / s_sigma
yi = y / s_sigma
interpolated = hl.Func('interpolated')
interpolated[x, y, c] = hl.lerp(hl.lerp(hl.lerp(blury[xi, yi, zi, c], blury[xi+1, yi, zi, c], xf),
hl.lerp(blury[xi, yi+1, zi, c], blury[xi+1, yi+1, zi, c], xf), yf),
hl.lerp(hl.lerp(blury[xi, yi, zi+1, c], blury[xi+1, yi, zi+1, c], xf),
hl.lerp(blury[xi, yi+1, zi+1, c], blury[xi+1, yi+1, zi+1, c], xf), yf), zf)
# Normalize
bilateral_grid = hl.Func('bilateral_grid')
bilateral_grid[x, y] = interpolated[x, y, 0] / interpolated[x, y, 1]
target = hl.get_target_from_environment()
if target.has_gpu_feature():
# GPU schedule
# Currently running this directly from the Python code is very slow.
# Probably because of the dispatch time because generated code
# is same speed as C++ generated code.
print ("Compiling for GPU.")
histogram.compute_root().reorder(c, z, x, y).gpu_tile(x, y, 8, 8);
histogram.update().reorder(c, r.x, r.y, x, y).gpu_tile(x, y, xi, yi, 8, 8).unroll(c)
blurx.compute_root().gpu_tile(x, y, z, xi, yi, zi, 16, 16, 1)
blury.compute_root().gpu_tile(x, y, z, xi, yi, zi, 16, 16, 1)
blurz.compute_root().gpu_tile(x, y, z, xi, yi, zi, 8, 8, 4)
bilateral_grid.compute_root().gpu_tile(x, y, xi, yi, s_sigma, s_sigma)
else:
# CPU schedule
print ("Compiling for CPU.")
histogram.compute_root().parallel(z)
histogram.update().reorder(c, r.x, r.y, x, y).unroll(c)
blurz.compute_root().reorder(c, z, x, y).parallel(y).vectorize(x, 4).unroll(c)
blurx.compute_root().reorder(c, x, y, z).parallel(z).vectorize(x, 4).unroll(c)
blury.compute_root().reorder(c, x, y, z).parallel(z).vectorize(x, 4).unroll(c)
bilateral_grid.compute_root().parallel(y).vectorize(x, 4)
return bilateral_grid
def get_bilateral_grid(input, r_sigma, s_sigma):
x = hl.Var('x')
y = hl.Var('y')
z = hl.Var('z')
c = hl.Var('c')
xi = hl.Var("xi")
yi = hl.Var("yi")
zi = hl.Var("zi")
# Add a boundary condition
clamped = hl.BoundaryConditions.repeat_edge(input)
# Construct the bilateral grid
r = hl.RDom([(0, s_sigma), (0, s_sigma)], 'r')
val = clamped[x * s_sigma + r.x - s_sigma // 2, y * s_sigma + r.y - s_sigma // 2]
val = hl.clamp(val, 0.0, 1.0)
zi = hl.i32(val / r_sigma + 0.5)
histogram = hl.Func('histogram')
histogram[x, y, z, c] = 0.0
histogram[x, y, zi, c] += hl.select(c == 0, val, 1.0)
# Blur the histogram using a five-tap filter
blurx, blury, blurz = hl.Func('blurx'), hl.Func('blury'), hl.Func('blurz')
blurz[x, y, z, c] = histogram[x, y, z-2, c] + histogram[x, y, z-1, c]*4 + histogram[x, y, z, c]*6 + histogram[x, y, z+1, c]*4 + histogram[x, y, z+2, c]
blurx[x, y, z, c] = blurz[x-2, y, z, c] + blurz[x-1, y, z, c]*4 + blurz[x, y, z, c]*6 + blurz[x+1, y, z, c]*4 + blurz[x+2, y, z, c]
blury[x, y, z, c] = blurx[x, y-2, z, c] + blurx[x, y-1, z, c]*4 + blurx[x, y, z, c]*6 + blurx[x, y+1, z, c]*4 + blurx[x, y+2, z, c]
# Take trilinear samples to compute the output
val = hl.clamp(clamped[x, y], 0.0, 1.0)
zv = val / r_sigma
zi = hl.i32(zv)
zf = zv - zi
xf = hl.f32(x % s_sigma) / s_sigma
yf = hl.f32(y % s_sigma) / s_sigma
xi = x / s_sigma
yi = y / s_sigma
interpolated = hl.Func('interpolated')
interpolated[x, y, c] = hl.lerp(hl.lerp(hl.lerp(blury[xi, yi, zi, c], blury[xi+1, yi, zi, c], xf),
hl.lerp(blury[xi, yi+1, zi, c], blury[xi+1, yi+1, zi, c], xf), yf),
hl.lerp(hl.lerp(blury[xi, yi, zi+1, c], blury[xi+1, yi, zi+1, c], xf),
hl.lerp(blury[xi, yi+1, zi+1, c], blury[xi+1, yi+1, zi+1, c], xf), yf), zf)
# Normalize
bilateral_grid = hl.Func('bilateral_grid')
bilateral_grid[x, y] = interpolated[x, y, 0] / interpolated[x, y, 1]
target = hl.get_target_from_environment()
if target.has_gpu_feature():
# GPU schedule
# Currently running this directly from the Python code is very slow.
# Probably because of the dispatch time because generated code
# is same speed as C++ generated code.
print ("Compiling for GPU.")
histogram.compute_root().reorder(c, z, x, y).gpu_tile(x, y, 8, 8);
histogram.update().reorder(c, r.x, r.y, x, y).gpu_tile(x, y, xi, yi, 8, 8).unroll(c)
blurx.compute_root().gpu_tile(x, y, z, xi, yi, zi, 16, 16, 1)
blury.compute_root().gpu_tile(x, y, z, xi, yi, zi, 16, 16, 1)
blurz.compute_root().gpu_tile(x, y, z, xi, yi, zi, 8, 8, 4)
bilateral_grid.compute_root().gpu_tile(x, y, xi, yi, s_sigma, s_sigma)
else:
# CPU schedule
print ("Compiling for CPU.")
histogram.compute_root().parallel(z)
histogram.update().reorder(c, r.x, r.y, x, y).unroll(c)
blurz.compute_root().reorder(c, z, x, y).parallel(y).vectorize(x, 4).unroll(c)
blurx.compute_root().reorder(c, x, y, z).parallel(z).vectorize(x, 4).unroll(c)
blury.compute_root().reorder(c, x, y, z).parallel(z).vectorize(x, 4).unroll(c)
bilateral_grid.compute_root().parallel(y).vectorize(x, 4)
return bilateral_grid