/*
* 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.camera.core.streamsharing;
import static androidx.camera.core.impl.ImageFormatConstants.INTERNAL_DEFINED_IMAGE_FORMAT_PRIVATE;
import static androidx.camera.core.impl.ImageOutputConfig.OPTION_SUPPORTED_RESOLUTIONS;
import static androidx.camera.core.impl.utils.AspectRatioUtil.ASPECT_RATIO_16_9;
import static androidx.camera.core.impl.utils.AspectRatioUtil.ASPECT_RATIO_4_3;
import static androidx.camera.core.impl.utils.AspectRatioUtil.hasMatchingAspectRatio;
import static androidx.camera.core.impl.utils.TransformUtils.is90or270;
import static androidx.camera.core.impl.utils.TransformUtils.rectToSize;
import static androidx.camera.core.impl.utils.TransformUtils.reverseSize;
import static java.lang.Math.sqrt;
import android.graphics.Rect;
import android.graphics.RectF;
import android.util.Pair;
import android.util.Rational;
import android.util.Size;
import android.view.Surface;
import androidx.annotation.NonNull;
import androidx.annotation.RequiresApi;
import androidx.annotation.VisibleForTesting;
import androidx.camera.core.Logger;
import androidx.camera.core.impl.CameraInfoInternal;
import androidx.camera.core.impl.CameraInternal;
import androidx.camera.core.impl.MutableConfig;
import androidx.camera.core.impl.UseCaseConfig;
import androidx.camera.core.impl.utils.CompareSizesByArea;
import androidx.camera.core.internal.SupportedOutputSizesSorter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
/**
* A class for calculating parent resolutions based on the children's configs.
*/
@RequiresApi(21) // TODO(b/200306659): Remove and replace with annotation on package-info.java
public class ResolutionsMerger {
private static final String TAG = "ResolutionsMerger";
// The width to height ratio that has same area when cropping into 4:3 and 16:9.
private static final double SAME_AREA_WIDTH_HEIGHT_RATIO = sqrt(4.0 / 3.0 * 16.0 / 9.0);
@NonNull
private final Size mSensorSize;
@NonNull
private final Rational mSensorAspectRatio;
@NonNull
private final Rational mFallbackAspectRatio;
@NonNull
private final Set<UseCaseConfig<?>> mChildrenConfigs;
@NonNull
private final SupportedOutputSizesSorter mSizeSorter;
@NonNull
private final List<Size> mCameraSupportedSizes;
@NonNull
private final Map<UseCaseConfig<?>, List<Size>> mChildSizesCache = new HashMap<>();
ResolutionsMerger(@NonNull CameraInternal cameraInternal,
@NonNull Set<UseCaseConfig<?>> childrenConfigs) {
this(rectToSize(cameraInternal.getCameraControlInternal().getSensorRect()),
cameraInternal.getCameraInfoInternal(), childrenConfigs);
}
private ResolutionsMerger(@NonNull Size sensorSize, @NonNull CameraInfoInternal cameraInfo,
@NonNull Set<UseCaseConfig<?>> childrenConfigs) {
this(sensorSize, childrenConfigs, new SupportedOutputSizesSorter(cameraInfo, sensorSize),
cameraInfo.getSupportedResolutions(INTERNAL_DEFINED_IMAGE_FORMAT_PRIVATE));
}
@VisibleForTesting
ResolutionsMerger(@NonNull Size sensorSize, @NonNull Set<UseCaseConfig<?>> childrenConfigs,
@NonNull SupportedOutputSizesSorter supportedOutputSizesSorter,
@NonNull List<Size> cameraSupportedResolutions) {
mSensorSize = sensorSize;
mSensorAspectRatio = getSensorAspectRatio(sensorSize);
mFallbackAspectRatio = getFallbackAspectRatio(mSensorAspectRatio);
mChildrenConfigs = childrenConfigs;
mSizeSorter = supportedOutputSizesSorter;
mCameraSupportedSizes = cameraSupportedResolutions;
}
/**
* Returns a list of {@link Surface} resolution sorted by priority.
*
* <p> This method calculates the resolution for the parent {@link StreamSharing} based on 1)
* the supported PRIV resolutions, 2) the sensor size and 3) the children's configs.
*/
@NonNull
List<Size> getMergedResolutions(@NonNull MutableConfig parentConfig) {
List<Size> candidateSizes = mCameraSupportedSizes;
// Use parent config's supported resolutions when it is set (e.g. Extensions may have
// its limitations on resolutions).
List<Pair<Integer, Size[]>> parentSupportedSizesMap =
parentConfig.retrieveOption(OPTION_SUPPORTED_RESOLUTIONS, null);
if (parentSupportedSizesMap != null) {
candidateSizes = getSupportedPrivResolutions(parentSupportedSizesMap);
}
return selectParentResolutions(candidateSizes);
}
/**
* Returns a preferred pair composed of a crop rect before scaling and a size after scaling.
*
* <p>The first size in the child's ordered size list that does not require the parent to
* upscale and does not cause double-cropping will be used to generate the pair, or {@code
* parentCropRect} will be used if no matching is found.
*
* <p>The returned crop rect and size will have the same aspect-ratio. When {@code
* isViewportSet}, the viewport setting will be respected, so the aspect-ratio of resulting
* crop rect and size will be same as {@code parentCropRect}.
*
* <p>Notes that the input {@code childConfig} is expected to be one of the values that use to
* construct the {@link ResolutionsMerger}, if not an IllegalArgumentException will be thrown.
*/
@NonNull
Pair<Rect, Size> getPreferredChildSizePair(@NonNull UseCaseConfig<?> childConfig,
@NonNull Rect parentCropRect, int sensorToBufferRotationDegrees,
boolean isViewportSet) {
// For easier in following computations, width and height are reverted when the rotation
// degrees of sensor-to-buffer is 90 or 270.
boolean isWidthHeightRevertedForComputation = false;
if (is90or270(sensorToBufferRotationDegrees)) {
parentCropRect = reverseRect(parentCropRect);
isWidthHeightRevertedForComputation = true;
}
// Get preferred child size pair.
Pair<Rect, Size> pair = getPreferredChildSizePairInternal(parentCropRect, childConfig,
isViewportSet);
Rect cropRectBeforeScaling = pair.first;
Size childSizeToScale = pair.second;
// Restore the reversion of width and height
if (isWidthHeightRevertedForComputation) {
childSizeToScale = reverseSize(childSizeToScale);
cropRectBeforeScaling = reverseRect(cropRectBeforeScaling);
}
return new Pair<>(cropRectBeforeScaling, childSizeToScale);
}
@NonNull
private Pair<Rect, Size> getPreferredChildSizePairInternal(@NonNull Rect parentCropRect,
@NonNull UseCaseConfig<?> childConfig, boolean isViewportSet) {
Rect cropRectBeforeScaling;
Size childSizeToScale;
if (isViewportSet) {
cropRectBeforeScaling = parentCropRect;
// When viewport is set, child size needs to be cropped to match viewport's
// aspect-ratio.
Size viewPortSize = rectToSize(parentCropRect);
childSizeToScale = getPreferredChildSizeForViewport(viewPortSize, childConfig);
} else {
Size parentSize = rectToSize(parentCropRect);
childSizeToScale = getPreferredChildSize(parentSize, childConfig);
cropRectBeforeScaling = getCropRectOfReferenceAspectRatio(parentSize, childSizeToScale);
}
return new Pair<>(cropRectBeforeScaling, childSizeToScale);
}
/**
* Returns the preferred child size with considering parent size and child's configuration.
*
* <p>Returns the first size in the child's ordered size list that can be cropped from {@code
* parentSize} without upscaling it, or {@code parentSize} if no matching is found.
*
* <p>The child size not causing double-cropping will be selected in priority.
*
* <p>Notes that the input {@code childConfig} is expected to be one of the values that use to
* construct the {@link ResolutionsMerger}, if not an IllegalArgumentException will be thrown.
*/
@VisibleForTesting
@NonNull
Size getPreferredChildSize(@NonNull Size parentSize, @NonNull UseCaseConfig<?> childConfig) {
// Select the first child resolution that does not result in double-cropping and upscaling.
List<Size> candidateChildSizes = getSortedChildSizes(childConfig);
for (Size childSize : candidateChildSizes) {
if (isDoubleCropping(parentSize, childSize)) {
continue;
}
if (!hasUpscaling(childSize, parentSize)) {
return childSize;
}
}
// Select the first child resolution that does not result in upscaling (might have
// smaller FOV due to double-cropping). This may occur when selecting parent resolutions
// that are expected to result in double-clipping in order to reduce binding failures in
// edge cases.
for (Size childSize : candidateChildSizes) {
if (!hasUpscaling(childSize, parentSize)) {
return childSize;
}
}
return parentSize;
}
/**
* Returns the preferred child size with considering config and viewport applied parent size.
*
* <p>Returns the first size in the child's ordered size list that can be cropped to same
* aspect-ratio as {@code parentSize} without upscaling, or {@code parentSize} if no matching
* is found.
*
* <p>Notes that the input {@code childConfig} is expected to be one of the values that use to
* construct the {@link ResolutionsMerger}, if not an IllegalArgumentException will be thrown.
*/
@VisibleForTesting
@NonNull
Size getPreferredChildSizeForViewport(@NonNull Size parentSize,
@NonNull UseCaseConfig<?> childConfig) {
List<Size> candidateChildSizes = getSortedChildSizes(childConfig);
for (Size childSize : candidateChildSizes) {
Size childSizeToCrop = rectToSize(
getCropRectOfReferenceAspectRatio(childSize, parentSize));
if (!hasUpscaling(childSizeToCrop, parentSize)) {
return childSizeToCrop;
}
}
return parentSize;
}
@NonNull
private List<Size> selectParentResolutions(@NonNull List<Size> candidateParentResolutions) {
// The following sequence of parent resolution selection is used to prevent double-cropping
// from happening:
// 1. Add sensor aspect-ratio resolutions, which do not result in double-cropping with any
// aspect-ratio of child resolution. This is to provide parent resolution that can be
// accepted by children in general cases.
// 2. Add fallback aspect-ratio (the one between 4:3 and 16:9 that is not sensor
// aspect-ratio) resolutions, that can crop/downscale to at least one child size for
// each child.
// 3. Add other aspect-ratio resolutions, that can crop/downscale to at least one child
// size for each child.
// The parent sizes added in step 2 and step 3 will only be used to crop to child sizes
// that do not result in double-cropping. For example, if childRatio < parentRatio <
// sensorRatio or childRatio > parentRatio > sensorRatio, then there is no double-cropping.
List<Size> result = new ArrayList<>();
// Add resolutions for sensor aspect-ratio.
if (needToAddSensorResolutions()) {
result.addAll(selectParentResolutionsByAspectRatio(mSensorAspectRatio,
candidateParentResolutions, false));
}
// Add resolutions for fallback aspect-ratio.
result.addAll(selectParentResolutionsByAspectRatio(mFallbackAspectRatio,
candidateParentResolutions, false));
// Add other aspect-ratio resolutions. Resolutions with larger FOV will be added first.
result.addAll(selectOtherAspectRatioParentResolutionsWithFovPriority(
candidateParentResolutions, false));
if (result.isEmpty()) {
// When the resulting parent resolution list is empty (this may be due to the camera
// not supporting 4:3 and 16:9 resolutions or a strict ResolutionSelector settings),
// add resolutions that are neither 4:3 nor 16:9 to prevent binding failures.
// Resolutions with larger FOV will be added first.
result.addAll(selectOtherAspectRatioParentResolutionsWithFovPriority(
candidateParentResolutions, true));
}
Logger.d(TAG, "Parent resolutions: " + result);
return result;
}
private List<Size> selectParentResolutionsByAspectRatio(@NonNull Rational aspectRatio,
@NonNull List<Size> candidateParentResolutions, boolean allowDoubleCropping) {
List<Size> candidates = filterResolutionsByAspectRatio(aspectRatio,
candidateParentResolutions);
sortInDescendingOrder(candidates);
// Filter resolutions that are too small and track resolutions that might be too large.
Set<Size> sizesTooLarge = new HashSet<>(candidates);
for (UseCaseConfig<?> childConfig : mChildrenConfigs) {
List<Size> childSizes = getSortedChildSizes(childConfig);
if (!allowDoubleCropping) {
childSizes = filterOutChildSizesCausingDoubleCropping(aspectRatio, childSizes);
}
if (childSizes.isEmpty()) {
// When the list is empty, which means no child sizes match requirement, make the
// parent list to be empty to reflect this.
return new ArrayList<>();
}
candidates = filterOutParentSizeThatIsTooSmall(childSizes, candidates);
sizesTooLarge.retainAll(getParentSizesThatAreTooLarge(childSizes, candidates));
}
// Filter out sizes that are too large.
List<Size> result = new ArrayList<>();
for (Size candidate : candidates) {
if (!sizesTooLarge.contains(candidate)) {
result.add(candidate);
}
}
return result;
}
@NonNull
private List<Size> selectOtherAspectRatioParentResolutionsWithFovPriority(
@NonNull List<Size> candidates, boolean allowDoubleCropping) {
Map<Rational, List<Size>> ratioToSizesMap = groupSizesByAspectRatio(candidates);
// Get aspect-ratio of candidate parent sizes and sort by overlapping area (FOV) in
// descending order.
List<Rational> ratios = new ArrayList<>(ratioToSizesMap.keySet());
sortByFov(ratios);
// Add resolutions that are neither 4:3 nor 16:9. Resolutions with larger FOV will be
// added first.
List<Size> result = new ArrayList<>();
for (Rational ratio: ratios) {
if (ratio.equals(ASPECT_RATIO_16_9) || ratio.equals(ASPECT_RATIO_4_3)) {
continue;
}
List<Size> sizes = Objects.requireNonNull(ratioToSizesMap.get(ratio));
result.addAll(selectParentResolutionsByAspectRatio(ratio, sizes, allowDoubleCropping));
}
return result;
}
@NonNull
private Map<Rational, List<Size>> groupSizesByAspectRatio(@NonNull List<Size> sizes) {
Map<Rational, List<Size>> result = new HashMap<>();
// Add 4:3 and 16:9 first so that other mod-16 sizes won't introduce additional keys.
result.put(ASPECT_RATIO_4_3, new ArrayList<>());
result.put(ASPECT_RATIO_16_9, new ArrayList<>());
// Add 4:3 and 16:9 first so that sizes won't be grouped to other close aspect-ratios.
List<Rational> ratios = new ArrayList<>();
ratios.add(ASPECT_RATIO_4_3);
ratios.add(ASPECT_RATIO_16_9);
// Group sizes by aspect-ratio with mod-16 considered.
for (Size size : sizes) {
if (size.getHeight() <= 0) {
continue;
}
// Get the aspect-ratio group if it is ready existed.
List<Size> group = null;
for (Rational ratio : ratios) {
if (hasMatchingAspectRatio(size, ratio)) {
group = result.get(ratio);
break;
}
}
// Create a new aspect-ratio group if it is not existed.
if (group == null) {
group = new ArrayList<>();
Rational newRatio = toRational(size);
ratios.add(newRatio);
result.put(newRatio, group);
}
Objects.requireNonNull(group).add(size);
}
return result;
}
/**
* Gets child sizes sorted by {@link SupportedOutputSizesSorter}.
*
* <p>Notes that the input {@code childConfig} is expected to be one of the values that use to
* construct the {@link ResolutionsMerger}, if not an IllegalArgumentException will be thrown.
*/
@NonNull
private List<Size> getSortedChildSizes(@NonNull UseCaseConfig<?> childConfig) {
if (!mChildrenConfigs.contains(childConfig)) {
throw new IllegalArgumentException("Invalid child config: " + childConfig);
}
// Since getSortedSupportedOutputSizes() might be time consuming, use caching to improve
// the performance.
if (mChildSizesCache.containsKey(childConfig)) {
return Objects.requireNonNull(mChildSizesCache.get(childConfig));
}
List<Size> childSizes = mSizeSorter.getSortedSupportedOutputSizes(childConfig);
mChildSizesCache.put(childConfig, childSizes);
return childSizes;
}
private boolean needToAddSensorResolutions() {
// Need to add sensor resolutions if any required resolution is not fallback aspect-ratio.
for (Size size : getChildrenRequiredResolutions()) {
if (!hasMatchingAspectRatio(size, mFallbackAspectRatio)) {
return true;
}
}
return false;
}
@NonNull
private Set<Size> getChildrenRequiredResolutions() {
Set<Size> result = new HashSet<>();
for (UseCaseConfig<?> childConfig : mChildrenConfigs) {
List<Size> childSizes = getSortedChildSizes(childConfig);
result.addAll(childSizes);
}
return result;
}
@NonNull
private List<Size> filterOutChildSizesCausingDoubleCropping(@NonNull Rational parentAspectRatio,
@NonNull List<Size> childSizes) {
List<Size> result = new ArrayList<>();
for (Size childSize: childSizes) {
if (!isDoubleCropping(parentAspectRatio, childSize)) {
result.add(childSize);
}
}
return result;
}
private boolean isDoubleCropping(@NonNull Rational parentRatio, @NonNull Size childSize) {
// No double cropping results when the sensor and parent have the same aspect ratio or
// when the parent and child have the same aspect ratio.
if (mSensorAspectRatio.equals(parentRatio) || hasMatchingAspectRatio(childSize,
parentRatio)) {
return false;
}
// When the cropping from sensor to parent and from parent to child are in the same
// direction, there is no double-cropping.
return areCroppingInDifferentDirection(
mSensorAspectRatio.floatValue(),
parentRatio.floatValue(),
toRationalWithMod16Considered(childSize).floatValue()
);
}
private boolean isDoubleCropping(@NonNull Size parentSize, @NonNull Size childSize) {
Rational parentRatio = toRationalWithMod16Considered(parentSize);
return isDoubleCropping(parentRatio, childSize);
}
private boolean areCroppingInDifferentDirection(float sensorRatioValue, float parentRatioValue,
float childRatioValue) {
// There is only one cropping direction When the sensor and parent have the same
// aspect-ratio or when the parent and child have the same aspect-ratio.
if (sensorRatioValue == parentRatioValue || parentRatioValue == childRatioValue) {
return false;
}
// When childRatio < parentRatio < sensorRatio or childRatio > parentRatio > sensorRatio,
// the cropping from sensor to parent and from parent to child are in the same direction.
if (sensorRatioValue > parentRatioValue) {
return parentRatioValue < childRatioValue;
} else {
return parentRatioValue > childRatioValue;
}
}
/**
* Sorts the input aspect-ratio by overlapping area with sensor (FOV) in descending order.
*/
private void sortByFov(@NonNull List<Rational> ratios) {
Rational actualSensorAspectRatio = toRational(mSensorSize);
Collections.sort(ratios, new CompareAspectRatioByOverlappingAreaToReference(
actualSensorAspectRatio, true));
}
/**
* Returns the crop rectangle for target that has the same aspect-ratio as the reference.
*/
@VisibleForTesting
@NonNull
static Rect getCropRectOfReferenceAspectRatio(@NonNull Size targetSize,
@NonNull Size referenceSize) {
Rational referenceRatio = toRational(referenceSize);
return getCenterCroppedRectangle(referenceRatio, targetSize);
}
@NonNull
private static List<Size> getSupportedPrivResolutions(
@NonNull List<Pair<Integer, Size[]>> supportedResolutionsMap) {
for (Pair<Integer, Size[]> pair : supportedResolutionsMap) {
if (pair.first.equals(INTERNAL_DEFINED_IMAGE_FORMAT_PRIVATE)) {
return Arrays.asList(pair.second);
}
}
return new ArrayList<>();
}
/**
* Returns the aspect-ratio of 4:3 or 16:9 that is closer to the sensor size.
*
* <p>Parent resolutions with sensor aspect-ratio are considered to be non-cropped, so child
* resolution can have a different aspect-ratio than the parents without causing
* double-cropping.
*/
@NonNull
private static Rational getSensorAspectRatio(@NonNull Size sensorSize) {
Rational result = findCloserAspectRatio(sensorSize);
Logger.d(TAG, "The closer aspect ratio to the sensor size (" + sensorSize + ") is "
+ result + ".");
return result;
}
@NonNull
private static Rational findCloserAspectRatio(@NonNull Size size) {
double widthHeightRatio = size.getWidth() / (double) size.getHeight();
if (widthHeightRatio > SAME_AREA_WIDTH_HEIGHT_RATIO) {
return ASPECT_RATIO_16_9;
} else {
return ASPECT_RATIO_4_3;
}
}
/** @noinspection SuspiciousNameCombination */
@VisibleForTesting
@NonNull
static Rect reverseRect(@NonNull Rect rect) {
return new Rect(rect.top, rect.left, rect.bottom, rect.right);
}
@NonNull
private static Rect getCenterCroppedRectangle(@NonNull Rational cropRatio,
@NonNull Size baseSize) {
int width = baseSize.getWidth();
int height = baseSize.getHeight();
Rational referenceRatio = toRational(baseSize);
RectF cropRectInFloat;
if (cropRatio.floatValue() == referenceRatio.floatValue()) {
cropRectInFloat = new RectF(0, 0, width, height);
} else if (cropRatio.floatValue() > referenceRatio.floatValue()) {
float cropHeight = width / cropRatio.floatValue();
float yOffset = (height - cropHeight) / 2;
cropRectInFloat = new RectF(0, yOffset, width, yOffset + cropHeight);
} else {
float cropWidth = height * cropRatio.floatValue();
float xOffset = (width - cropWidth) / 2;
cropRectInFloat = new RectF(xOffset, 0, xOffset + cropWidth, height);
}
// RectF to Rect.
Rect result = new Rect();
cropRectInFloat.round(result);
return result;
}
/**
* Returns the aspect-ratio of 4:3 or 16:9 that is not the sensor aspect-ratio.
*
* <p>Parent resolutions with fallback aspect-ratio are considered to be cropped, so child
* resolution should not different to the parent or double-cropping will happen.
*/
@NonNull
private static Rational getFallbackAspectRatio(@NonNull Rational sensorAspectRatio) {
if (sensorAspectRatio.equals(ASPECT_RATIO_4_3)) {
return ASPECT_RATIO_16_9;
} else if (sensorAspectRatio.equals(ASPECT_RATIO_16_9)) {
return ASPECT_RATIO_4_3;
} else {
throw new IllegalArgumentException("Invalid sensor aspect-ratio: " + sensorAspectRatio);
}
}
/**
* Sorts the input resolutions in descending order.
*/
@VisibleForTesting
static void sortInDescendingOrder(@NonNull List<Size> resolutions) {
Collections.sort(resolutions, new CompareSizesByArea(true));
}
/**
* Returns a list of resolution that all resolutions are with the input aspect-ratio.
*
* <p>The order of the {@code resolutionsToFilter} will be preserved in the resulting list.
*/
@VisibleForTesting
@NonNull
static List<Size> filterResolutionsByAspectRatio(@NonNull Rational aspectRatio,
@NonNull List<Size> resolutionsToFilter) {
List<Size> result = new ArrayList<>();
for (Size resolution : resolutionsToFilter) {
if (hasMatchingAspectRatio(resolution, aspectRatio)) {
result.add(resolution);
}
}
return result;
}
/**
* Filters out the parent size that is too small with consider target children sizes.
*
* <p>A size is too small if it cannot find any child size that can be cropped out without
* upscaling.
*
* <p>The order of the {@code parentSizes} will be preserved in the resulting list.
*/
@VisibleForTesting
@NonNull
static List<Size> filterOutParentSizeThatIsTooSmall(@NonNull Collection<Size> childSizes,
@NonNull List<Size> parentSizes) {
if (childSizes.isEmpty() || parentSizes.isEmpty()) {
return new ArrayList<>();
}
List<Size> result = new ArrayList<>();
for (Size parentSize : parentSizes) {
if (isAnyChildSizeCanBeCroppedOutWithoutUpscalingParent(childSizes, parentSize)) {
result.add(parentSize);
}
}
return result;
}
private static boolean isAnyChildSizeCanBeCroppedOutWithoutUpscalingParent(
@NonNull Collection<Size> childSizes, @NonNull Size parentSize) {
for (Size childSize : childSizes) {
if (!hasUpscaling(childSize, parentSize)) {
return true;
}
}
return false;
}
/**
* Returns resolutions that are too large with consider target children sizes.
*
* <p>A size is too large if there is another size smaller than that size and all children
* sizes can be cropped from that other size without upscaling.
*
* <p>The order of the {@code parentSizes} will be preserved in the resulting list.
*/
@VisibleForTesting
@NonNull
static List<Size> getParentSizesThatAreTooLarge(@NonNull Collection<Size> childSizes,
@NonNull List<Size> parentSizes) {
if (childSizes.isEmpty() || parentSizes.isEmpty()) {
return new ArrayList<>();
}
List<Size> result = new ArrayList<>();
for (Size parentSize : parentSizes) {
if (isAllChildSizesCanBeCroppedOutWithoutUpscalingParent(childSizes, parentSize)) {
result.add(parentSize);
}
}
// Remove the last element, which is the smallest parent size that can be cropped to all
// child sizes and should remain in the final parent size list.
if (!result.isEmpty()) {
result.remove(result.size() - 1);
}
return result;
}
private static boolean isAllChildSizesCanBeCroppedOutWithoutUpscalingParent(
@NonNull Collection<Size> childSizes, @NonNull Size parentSize) {
for (Size childSize : childSizes) {
if (hasUpscaling(childSize, parentSize)) {
return false;
}
}
return true;
}
/**
* Whether the parent size needs upscaling to fill the child size.
*/
@VisibleForTesting
static boolean hasUpscaling(@NonNull Size childSize, @NonNull Size parentSize) {
// Upscaling is needed if child size is larger than the parent.
return childSize.getHeight() > parentSize.getHeight()
|| childSize.getWidth() > parentSize.getWidth();
}
@NonNull
private static Rational toRationalWithMod16Considered(@NonNull Size size) {
// For 4:3 and 16:9, use hasMatchingAspectRatio to take "mod 16 calculation" into
// consideration. For example, a standard 16:9 supported size is 1920x1080. It may become
// 1920x1088 on some devices because 1088 is multiple of 16.
if (hasMatchingAspectRatio(size, ASPECT_RATIO_4_3)) {
return ASPECT_RATIO_4_3;
} else if (hasMatchingAspectRatio(size, ASPECT_RATIO_16_9)) {
return ASPECT_RATIO_16_9;
} else {
return toRational(size);
}
}
@NonNull
private static Rational toRational(@NonNull Size size) {
return new Rational(size.getWidth(), size.getHeight());
}
private static float computeAreaOverlapping(@NonNull Rational croppingRatio,
@NonNull Rational baseRatio) {
float croppingRatioValue = croppingRatio.floatValue();
float baseRatioValue = baseRatio.floatValue();
return (croppingRatioValue > baseRatioValue) ? baseRatioValue / croppingRatioValue
: croppingRatioValue / baseRatioValue;
}
private static class CompareAspectRatioByOverlappingAreaToReference implements
Comparator<Rational> {
@NonNull
private final Rational mReferenceAspectRatio;
private final boolean mReverse;
/** Creates a comparator which can reverse the total ordering. */
CompareAspectRatioByOverlappingAreaToReference(@NonNull Rational referenceAspectRatio,
boolean reverse) {
mReferenceAspectRatio = referenceAspectRatio;
mReverse = reverse;
}
@Override
public int compare(@NonNull Rational lhs, @NonNull Rational rhs) {
float lhsOverlapping = computeAreaOverlapping(lhs, mReferenceAspectRatio);
float rhsOverlapping = computeAreaOverlapping(rhs, mReferenceAspectRatio);
if (mReverse) {
return Float.compare(rhsOverlapping, lhsOverlapping);
} else {
return Float.compare(lhsOverlapping, rhsOverlapping);
}
}
}
}