ColorUtils.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.muxer;
import android.media.MediaFormat;
import com.google.common.collect.ImmutableList;
/** Utilities for color information. */
/* package */ final class ColorUtils {
// The constants are defined as per ISO/IEC 29199-2 (mentioned in MP4 spec ISO/IEC 14496-12:
// 8.5.2.3).
private static final short TRANSFER_SMPTE170_M = 1; // Main; also 6, 14 and 15
private static final short TRANSFER_UNSPECIFIED = 2;
private static final short TRANSFER_GAMMA22 = 4;
private static final short TRANSFER_GAMMA28 = 5;
private static final short TRANSFER_SMPTE240_M = 7;
private static final short TRANSFER_LINEAR = 8;
private static final short TRANSFER_OTHER = 9; // Also 10
private static final short TRANSFER_XV_YCC = 11;
private static final short TRANSFER_BT1361 = 12;
private static final short TRANSFER_SRGB = 13;
private static final short TRANSFER_ST2084 = 16;
private static final short TRANSFER_ST428 = 17;
private static final short TRANSFER_HLG = 18;
// MediaFormat contains three color-related fields: "standard", "transfer" and "range". The color
// standard maps to "primaries" and "matrix" in the "colr" box, while "transfer" and "range" are
// mapped to a single value each (although for "transfer", it's still not the same enum values).
private static final short PRIMARIES_BT709_5 = 1;
private static final short PRIMARIES_UNSPECIFIED = 2;
private static final short PRIMARIES_BT601_6_625 = 5;
private static final short PRIMARIES_BT601_6_525 = 6; // It's also 7?
private static final short PRIMARIES_GENERIC_FILM = 8;
private static final short PRIMARIES_BT2020 = 9;
private static final short PRIMARIES_BT470_6_M = 4;
private static final short MATRIX_UNSPECIFIED = 2;
private static final short MATRIX_BT709_5 = 1;
private static final short MATRIX_BT601_6 = 6;
private static final short MATRIX_SMPTE240_M = 7;
private static final short MATRIX_BT2020 = 9;
private static final short MATRIX_BT2020_CONSTANT = 10;
private static final short MATRIX_BT470_6_M = 4;
/**
* Map from {@link MediaFormat} standards to MP4 primaries and matrix indices.
*
* <p>The i-th element corresponds to a {@link MediaFormat} value of i.
*/
public static final ImmutableList<ImmutableList<Short>>
MEDIAFORMAT_STANDARD_TO_PRIMARIES_AND_MATRIX =
ImmutableList.of(
ImmutableList.of(PRIMARIES_UNSPECIFIED, MATRIX_UNSPECIFIED), // Unspecified
ImmutableList.of(PRIMARIES_BT709_5, MATRIX_BT709_5), // BT709
ImmutableList.of(PRIMARIES_BT601_6_625, MATRIX_BT601_6), // BT601_625
ImmutableList.of(PRIMARIES_BT601_6_625, MATRIX_BT709_5), // BT601_625_Unadjusted
ImmutableList.of(PRIMARIES_BT601_6_525, MATRIX_BT601_6), // BT601_525
ImmutableList.of(PRIMARIES_BT601_6_525, MATRIX_SMPTE240_M), // BT601_525_Unadjusted
ImmutableList.of(PRIMARIES_BT2020, MATRIX_BT2020), // BT2020
ImmutableList.of(PRIMARIES_BT2020, MATRIX_BT2020_CONSTANT), // BT2020Constant
ImmutableList.of(PRIMARIES_BT470_6_M, MATRIX_BT470_6_M), // BT470M
ImmutableList.of(PRIMARIES_GENERIC_FILM, MATRIX_BT2020) // Film
);
/**
* Map from {@link MediaFormat} standards to MP4 transfer indices.
*
* <p>The i-th element corresponds to a {@link MediaFormat} value of i.
*/
public static final ImmutableList<Short> MEDIAFORMAT_TRANSFER_TO_MP4_TRANSFER =
ImmutableList.of(
TRANSFER_UNSPECIFIED, // Unspecified
TRANSFER_LINEAR, // Linear
TRANSFER_SRGB, // SRGB
TRANSFER_SMPTE170_M, // SMPTE_170M
TRANSFER_GAMMA22, // Gamma22
TRANSFER_GAMMA28, // Gamma28
TRANSFER_ST2084, // ST2084
TRANSFER_HLG // HLG
);
private ColorUtils() {}
}