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56 lines
1.7 KiB
C
56 lines
1.7 KiB
C
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/*
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* Copyright 2020 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef FLOWGRAPH_UTILITIES_H
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#define FLOWGRAPH_UTILITIES_H
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#include <unistd.h>
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using namespace FLOWGRAPH_OUTER_NAMESPACE::flowgraph;
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class FlowgraphUtilities {
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public:
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// This was copied from audio_utils/primitives.h
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/**
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* Convert a single-precision floating point value to a Q0.31 integer value.
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* Rounds to nearest, ties away from 0.
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*
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* Values outside the range [-1.0, 1.0) are properly clamped to -2147483648 and 2147483647,
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* including -Inf and +Inf. NaN values are considered undefined, and behavior may change
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* depending on hardware and future implementation of this function.
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*/
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static int32_t clamp32FromFloat(float f)
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{
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static const float scale = (float)(1UL << 31);
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static const float limpos = 1.;
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static const float limneg = -1.;
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if (f <= limneg) {
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return -0x80000000; /* or 0x80000000 */
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} else if (f >= limpos) {
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return 0x7fffffff;
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}
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f *= scale;
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/* integer conversion is through truncation (though int to float is not).
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* ensure that we round to nearest, ties away from 0.
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*/
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return f > 0 ? f + 0.5 : f - 0.5;
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}
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};
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#endif // FLOWGRAPH_UTILITIES_H
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