1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "ip.rsh" 18 // #pragma rs_fp_relaxed 19 20 static float brightM = 1.4142136f; 21 static float brightC = -50.948268f; 22 23 /* 24 void setBright(float v) { 25 brightM = pow(2.f, v / 100.f); 26 brightC = 127.f - brightM * 127.f; 27 } 28 */ 29 30 float4 RS_KERNEL contrast(float4 in) { 31 return in * brightM + brightC; 32 } 33