image_resizer.h

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/*
 * Copyright 2013 Google Inc.
 *
 * 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 PAGESPEED_KERNEL_IMAGE_IMAGE_RESIZER_H_
#define PAGESPEED_KERNEL_IMAGE_IMAGE_RESIZER_H_

#include <cstddef>
#include "pagespeed/kernel/base/basictypes.h"
#include "pagespeed/kernel/base/message_handler.h"
#include "pagespeed/kernel/base/scoped_ptr.h"
#include "pagespeed/kernel/image/image_util.h"
#include "pagespeed/kernel/image/scanline_interface.h"
#include "pagespeed/kernel/image/scanline_status.h"

namespace pagespeed {

namespace image_compression {

using net_instaweb::MessageHandler;

class ResizeRow;
class ResizeCol;

class ScanlineResizer : public ScanlineReaderInterface {
 public:
  explicit ScanlineResizer(MessageHandler* handler);
  virtual ~ScanlineResizer();

  bool Initialize(ScanlineReaderInterface* reader,
                  size_t output_width,
                  size_t output_height);

  virtual ScanlineStatus ReadNextScanlineWithStatus(void** out_scanline_bytes);

  virtual bool Reset();

  virtual size_t GetBytesPerScanline() {
    return static_cast<size_t>(elements_per_row_);
  }

  virtual bool HasMoreScanLines();

  virtual size_t GetImageHeight() {
    return static_cast<size_t>(height_);
  }

  virtual size_t GetImageWidth() {
    return static_cast<size_t>(width_);
  }

  virtual PixelFormat GetPixelFormat() {
    return reader_->GetPixelFormat();
  }

  virtual bool IsProgressive() {
    return reader_->IsProgressive();
  }

  virtual ScanlineStatus InitializeWithStatus(const void* image_buffer,
                                              size_t buffer_length);

  static const size_t kPreserveAspectRatio = 0;

 private:
  ScanlineReaderInterface* reader_;
  net_instaweb::scoped_ptr<ResizeRow> resizer_x_;
  net_instaweb::scoped_ptr<ResizeCol> resizer_y_;

  net_instaweb::scoped_array<uint8> output_;
  int width_;
  int height_;
  int elements_per_row_;

  net_instaweb::scoped_array<float> buffer_;
  int bytes_per_buffer_row_;
  MessageHandler* message_handler_;

  
};

}  

}  

#endif