cavis/libnd4j/include/ops/declarable/generic/parity_ops/adjust_contrast.cpp

102 lines
3.8 KiB
C++

/*******************************************************************************
* Copyright (c) 2015-2018 Skymind, Inc.
*
* This program and the accompanying materials are made available under the
* terms of the Apache License, Version 2.0 which is available at
* https://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* SPDX-License-Identifier: Apache-2.0
******************************************************************************/
//
// @author George A. Shulinok <sgazeos@gmail.com>
//
#include <op_boilerplate.h>
#if NOT_EXCLUDED(OP_adjust_contrast)
#include <ops/declarable/headers/parity_ops.h>
#include <NDArrayFactory.h>
namespace nd4j {
namespace ops {
CONFIGURABLE_OP_IMPL(adjust_contrast, 1, 1, true, -2, 0) {
auto input = INPUT_VARIABLE(0);
auto output = OUTPUT_VARIABLE(0);
REQUIRE_TRUE(block.numT() > 0 || block.width() > 1, 0, "ADJUST_CONTRAST: Scale factor required");
const double factor = block.width() > 1 ? INPUT_VARIABLE(1)->e<double>(0) : T_ARG(0);
REQUIRE_TRUE(input->rankOf() > 2, 0, "ADJUST_CONTRAST: op expects rank of input array to be >= 3, but got %i instead", input->rankOf());
REQUIRE_TRUE(input->sizeAt(-1) == 3, 0, "ADJUST_CONTRAST: operation expects image with 3 channels (R, G, B), but got %i instead", input->sizeAt(-1));
// compute mean before
// fill up axes vector first
std::vector<int> axes(input->rankOf() - 1);
for (auto i = 0; i < axes.size(); ++i)
axes[i] = i;
// mean as reduction for last dimension set
auto mean = input->reduceAlongDims(reduce::Mean, axes);
NDArray factorT(output->dataType(), block.launchContext()); // = NDArrayFactory::create(factor, block.launchContext());
factorT.p(0, factor);
// this is contrast calculation
output->assign((*input - mean) * factorT + mean);
return Status::OK();
}
DECLARE_TYPES(adjust_contrast) {
getOpDescriptor()->setAllowedInputTypes(nd4j::DataType::ANY)
->setAllowedOutputTypes({ALL_FLOATS})
->setSameMode(true);
}
CONFIGURABLE_OP_IMPL(adjust_contrast_v2, 1, 1, true, -2, 0) {
auto input = INPUT_VARIABLE(0);
auto output = OUTPUT_VARIABLE(0);
REQUIRE_TRUE(block.numT() > 0 || block.width() > 1, 0, "ADJUST_CONTRAST_V2: Scale factor required");
const double factor = block.width() > 1 ? INPUT_VARIABLE(1)->e<double>(0) : T_ARG(0);
REQUIRE_TRUE(input->rankOf() > 2, 0, "ADJUST_CONTRAST_V2: op expects rank of input array to be >= 3, but got %i instead", input->rankOf());
REQUIRE_TRUE(input->sizeAt(-1) == 3, 0, "ADJUST_CONTRAST_V2: operation expects image with 3 channels (R, G, B), but got %i instead", input->sizeAt(-1));
// compute mean before
std::vector<int> axes(input->rankOf() - 1);
for (auto i = 0; i < axes.size(); ++i)
axes[i] = i;
// mean as reduction for last dimension set
auto mean = input->reduceAlongDims(reduce::Mean, axes);
// result as (x - mean) * factor + mean
auto temp = input->ulike();
input->applyTrueBroadcast(BroadcastOpsTuple::Subtract(), &mean, &temp);
temp.applyScalar(scalar::Multiply, factor);
temp.applyTrueBroadcast(BroadcastOpsTuple::Add(), &mean, output);
return Status::OK();
}
DECLARE_TYPES(adjust_contrast_v2) {
getOpDescriptor()->setAllowedInputTypes(nd4j::DataType::ANY)
->setAllowedOutputTypes({ALL_FLOATS})
->setSameMode(true);
}
}
}
#endif