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# to you under the Apache License, Version 2.0 (the
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#
#   http://www.apache.org/licenses/LICENSE-2.0
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"""Test code for upsampling"""
import numpy as np
import tvm
import topi
import topi.testing
import math

from common import get_all_backend

def verify_upsampling(batch, in_channel, in_height, in_width, scale_h, scale_w,
                      layout='NCHW', method="nearest_neighbor"):
    if layout == 'NCHW':
        A = tvm.placeholder((batch, in_channel, in_height, in_width), name='A')
        dtype = A.dtype
        out_shape = (batch, in_channel, int(round(in_height*scale_h)), int(round(in_width*scale_w)))
        a_np = np.random.uniform(size=(batch, in_channel, in_height, in_width)).astype(dtype)
    elif layout == 'NHWC':
        A = tvm.placeholder((batch, in_height, in_width, in_channel), name='A')
        dtype = A.dtype
        out_shape = (batch, int(round(in_height*scale_h)), int(round(in_width*scale_w)), in_channel)
        a_np = np.random.uniform(size=(batch, in_height, in_width, in_channel)).astype(dtype)
    else:
        raise NotImplementedError(
            'Layout not supported {} '.format(layout))

    B = topi.nn.upsampling(A, scale_h, scale_w, layout=layout, method=method, align_corners=False)

    if method == "bilinear":
        out_size = (int(round(in_height*scale_h)), int(round(in_width*scale_w)))
        b_np = topi.testing.bilinear_resize_python(a_np, out_size, layout, align_corners=False)
    else:
        b_np = topi.testing.upsampling_python(a_np, (scale_h, scale_w), layout)

    def check_device(device):
        ctx = tvm.context(device, 0)
        if not ctx.exist:
            print("Skip because %s is not enabled" % device)
            return
        print("Running on target: %s" % device)
        with tvm.target.create(device):
            s = topi.generic.schedule_injective(B)
        a = tvm.nd.array(a_np, ctx)
        b = tvm.nd.array(np.zeros(out_shape, dtype=dtype), ctx)
        f = tvm.build(s, [A, B], device)
        f(a, b)

        tvm.testing.assert_allclose(b.asnumpy(), b_np, rtol=1e-5, atol=1e-5)

    for device in get_all_backend():
        check_device(device)

def test_upsampling():
    # nearest_neighbor - NCHW
    verify_upsampling(8, 16, 32, 32, 2.0, 2.0)
    verify_upsampling(2, 32, 64, 64, 3.0, 3.0)
    verify_upsampling(1, 64, 22, 32, 1.954545497894287, 2.0)

    ## nearest_neighbor - NHWC
    verify_upsampling(8, 16, 32, 32, 2.0, 2.0, layout="NHWC")
    verify_upsampling(2, 32, 64, 64, 3.0, 3.0, layout="NHWC")
    verify_upsampling(1, 64, 22, 32, 1.954545497894287, 2.0, layout="NHWC")

    # bilinear - NCHW
    verify_upsampling(2, 2, 32, 32, 2.0, 2.0, method="bilinear")
    verify_upsampling(2, 2, 32, 32, 3.0, 3.0, method="bilinear")
    verify_upsampling(1, 64, 22, 32, 1.954545497894287, 2.0, method="bilinear")

    # bilinear - NHWC
    verify_upsampling(2, 2, 32, 32, 2.0, 2.0, layout="NHWC", method="bilinear")
    verify_upsampling(2, 2, 32, 32, 3.0, 3.0, layout="NHWC", method="bilinear")
    verify_upsampling(1, 64, 22, 32,  3.0, 3.0, layout="NHWC", method="bilinear")

if __name__ == "__main__":
    test_upsampling()
