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diff --git a/system/hwc3/AlternatingImageStorage.h b/system/hwc3/AlternatingImageStorage.h
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+/*
+ * 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.
+ */
+
+#ifndef ANDROID_HWC_ALTERNATINGIMAGESTORAGE_H
+#define ANDROID_HWC_ALTERNATINGIMAGESTORAGE_H
+
+#include <stdint.h>
+#include <vector>
+
+#include "Common.h"
+
+namespace aidl::android::hardware::graphics::composer3::impl {
+
+// Provides storage for images when transforming images with the expectation
+// that image N will no longer be used after producing image N + 1. With this,
+// the storage just needs to be 2x the needed image size and the returned buffers
+// can alternate back and forth.
+class AlternatingImageStorage {
+ public:
+  AlternatingImageStorage() = default;
+
+  uint8_t* getRotatingScratchBuffer(std::size_t neededSize, std::uint32_t imageIndex);
+
+  uint8_t* getSpecialScratchBuffer(std::size_t neededSize);
+
+ private:
+  static constexpr const int kNumScratchBufferPieces = 2;
+
+  // The main alternating storage.
+  std::vector<uint8_t> mScratchBuffer;
+
+  // Extra additional storage for one-off operations (scaling).
+  std::vector<uint8_t> mSpecialScratchBuffer;
+};
+
+}  // namespace aidl::android::hardware::graphics::composer3::impl
+
+#endif