Brightness.java
/*
* Copyright 2023 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://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.
*/
package androidx.media3.effect;
import static androidx.media3.common.util.Assertions.checkArgument;
import android.opengl.Matrix;
import androidx.annotation.FloatRange;
import androidx.media3.common.util.GlUtil;
import androidx.media3.common.util.UnstableApi;
import java.util.Arrays;
/** Modifies brightness of an input frame. */
@UnstableApi
public class Brightness implements RgbMatrix {
private final float[] rgbMatrix;
/**
* Modifies brightness by adding a constant value to red, green, and blue values.
*
* @param brightness The constant value to add to red, green, and blue values. Should be greater
* than or equal to {@code -1f}, and less than or equal to {@code 1f}. {@code 0} means to
* leave brightness unchanged.
*/
public Brightness(@FloatRange(from = -1, to = 1) float brightness) {
checkArgument(
brightness >= -1f && brightness <= 1f,
"brightness value outside of range from -1f to 1f, inclusive");
rgbMatrix = GlUtil.create4x4IdentityMatrix();
Matrix.translateM(
rgbMatrix,
/* smOffset= */ 0,
/* x= */ brightness,
/* y= */ brightness,
/* z= */ brightness);
}
@Override
public float[] getMatrix(long presentationTimeUs, boolean useHdr) {
checkArgument(!useHdr, "HDR is not supported.");
return rgbMatrix;
}
@Override
public boolean isNoOp(int inputWidth, int inputHeight) {
return Arrays.equals(rgbMatrix, GlUtil.create4x4IdentityMatrix());
}
}