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diff --git a/lib/include/ultrahdr/jpegencoderhelper.h b/lib/include/ultrahdr/jpegencoderhelper.h
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+/*
+ * Copyright 2022 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 ULTRAHDR_JPEGENCODERHELPER_H
+#define ULTRAHDR_JPEGENCODERHELPER_H
+
+#include <stdio.h>  // For jpeglib.h.
+
+// C++ build requires extern C for jpeg internals.
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <jerror.h>
+#include <jpeglib.h>
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#include <cstdint>
+#include <vector>
+
+namespace ultrahdr {
+
+/*
+ * Encapsulates a converter from raw image (YUV420planer or grey-scale) to JPEG format.
+ * This class is not thread-safe.
+ */
+class JpegEncoderHelper {
+ public:
+  JpegEncoderHelper();
+  ~JpegEncoderHelper();
+
+  /*
+   * Compresses YUV420Planer image to JPEG format. After calling this method, call
+   * getCompressedImage() to get the image. |quality| is the jpeg image quality parameter to use.
+   * It ranges from 1 (poorest quality) to 100 (highest quality). |iccBuffer| is the buffer of
+   * ICC segment which will be added to the compressed image.
+   * Returns false if errors occur during compression.
+   */
+  bool compressImage(const uint8_t* yBuffer, const uint8_t* uvBuffer, int width, int height,
+                     int lumaStride, int chromaStride, int quality, const void* iccBuffer,
+                     unsigned int iccSize);
+
+  /*
+   * Returns the compressed JPEG buffer pointer. This method must be called only after calling
+   * compressImage().
+   */
+  void* getCompressedImagePtr();
+
+  /*
+   * Returns the compressed JPEG buffer size. This method must be called only after calling
+   * compressImage().
+   */
+  size_t getCompressedImageSize();
+
+  /*
+   * Process 16 lines of Y and 16 lines of U/V each time.
+   * We must pass at least 16 scanlines according to libjpeg documentation.
+   */
+  static const int kCompressBatchSize = 16;
+
+ private:
+  // initDestination(), emptyOutputBuffer() and emptyOutputBuffer() are callback functions to be
+  // passed into jpeg library.
+  static void initDestination(j_compress_ptr cinfo);
+  static boolean emptyOutputBuffer(j_compress_ptr cinfo);
+  static void terminateDestination(j_compress_ptr cinfo);
+  static void outputErrorMessage(j_common_ptr cinfo);
+
+  // Returns false if errors occur.
+  bool encode(const uint8_t* yBuffer, const uint8_t* uvBuffer, int width, int height,
+              int lumaStride, int chromaStride, int quality, const void* iccBuffer,
+              unsigned int iccSize);
+  void setJpegDestination(jpeg_compress_struct* cinfo);
+  void setJpegCompressStruct(int width, int height, int quality, jpeg_compress_struct* cinfo,
+                             bool isSingleChannel);
+  // Returns false if errors occur.
+  bool compressYuv(jpeg_compress_struct* cinfo, const uint8_t* yBuffer, const uint8_t* uvBuffer,
+                   int lumaStride, int chromaStride);
+  bool compressY(jpeg_compress_struct* cinfo, const uint8_t* yBuffer, int lumaStride);
+
+  // The block size for encoded jpeg image buffer.
+  static const int kBlockSize = 16384;
+
+  // The buffer that holds the compressed result.
+  std::vector<JOCTET> mResultBuffer;
+};
+
+} /* namespace ultrahdr  */
+
+#endif  // ULTRAHDR_JPEGENCODERHELPER_H