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/*
 * Copyright (C) 2012 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.
 */

/**
 * This class simulates a hardware JPEG compressor.  It receives image buffers
 * in RGBA_8888 format, processes them in a worker thread, and then pushes them
 * out to their destination stream.
 */

#ifndef HW_EMULATOR_CAMERA2_JPEG_H
#define HW_EMULATOR_CAMERA2_JPEG_H

#include "utils/Mutex.h"
#include "utils/Thread.h"
#include "utils/Timers.h"

#include "Base.h"

#include <stdio.h>

extern "C" {
#include <jpeglib.h>
}

namespace android {

class JpegCompressor : private Thread, public virtual RefBase {
 public:
  JpegCompressor();
  ~JpegCompressor();

  struct JpegListener {
    // Called when JPEG compression has finished, or encountered an error
    virtual void onJpegDone(const StreamBuffer &jpegBuffer, bool success) = 0;
    // Called when the input buffer for JPEG is not needed any more,
    // if the buffer came from the framework.
    virtual void onJpegInputDone(const StreamBuffer &inputBuffer) = 0;
    virtual ~JpegListener();
  };

  // Start compressing COMPRESSED format buffers; JpegCompressor takes
  // ownership of the Buffers vector.
  // Reserve() must be called first.
  status_t start(Buffers *buffers, JpegListener *listener);

  // Compress and block until buffer is complete.
  status_t compressSynchronous(Buffers *buffers);

  status_t cancel();

  bool isBusy();
  bool isStreamInUse(uint32_t id);

  bool waitForDone(nsecs_t timeout);

  // Reserve the compressor for a later start() call.
  status_t reserve();

  // TODO: Measure this
  static const size_t kMaxJpegSize = 300000;

 private:
  Mutex mBusyMutex;
  bool mIsBusy;
  Condition mDone;
  bool mSynchronous;

  Mutex mMutex;

  Buffers *mBuffers;
  JpegListener *mListener;

  StreamBuffer mJpegBuffer, mAuxBuffer;
  bool mFoundJpeg, mFoundAux;

  jpeg_compress_struct mCInfo;

  struct JpegError : public jpeg_error_mgr {
    JpegCompressor *parent;
  };
  j_common_ptr mJpegErrorInfo;

  struct JpegDestination : public jpeg_destination_mgr {
    JpegCompressor *parent;
  };

  static void jpegErrorHandler(j_common_ptr cinfo);

  static void jpegInitDestination(j_compress_ptr cinfo);
  static boolean jpegEmptyOutputBuffer(j_compress_ptr cinfo);
  static void jpegTermDestination(j_compress_ptr cinfo);

  bool checkError(const char *msg);
  status_t compress();

  void cleanUp();

  /**
   * Inherited Thread virtual overrides
   */
 private:
  virtual status_t readyToRun();
  virtual bool threadLoop();
};

}  // namespace android

#endif