FasTC/PVRTCEncoder/src/Compressor.cpp

/* FasTC
 * Copyright (c) 2013 University of North Carolina at Chapel Hill.
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation for educational, research, and non-profit purposes, without
 * fee, and without a written agreement is hereby granted, provided that the
 * above copyright notice, this paragraph, and the following four paragraphs
 * appear in all copies.
 *
 * Permission to incorporate this software into commercial products may be
 * obtained by contacting the authors or the Office of Technology Development
 * at the University of North Carolina at Chapel Hill <otd@unc.edu>.
 *
 * This software program and documentation are copyrighted by the University of
 * North Carolina at Chapel Hill. The software program and documentation are
 * supplied "as is," without any accompanying services from the University of
 * North Carolina at Chapel Hill or the authors. The University of North
 * Carolina at Chapel Hill and the authors do not warrant that the operation of
 * the program will be uninterrupted or error-free. The end-user understands
 * that the program was developed for research purposes and is advised not to
 * rely exclusively on the program for any reason.
 *
 * IN NO EVENT SHALL THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL OR THE
 * AUTHORS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL,
 * OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF
 * THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF NORTH CAROLINA
 * AT CHAPEL HILL OR THE AUTHORS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * THE UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL AND THE AUTHORS SPECIFICALLY
 * DISCLAIM ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE AND ANY 
 * STATUTORY WARRANTY OF NON-INFRINGEMENT. THE SOFTWARE PROVIDED HEREUNDER IS ON
 * AN "AS IS" BASIS, AND THE UNIVERSITY  OF NORTH CAROLINA AT CHAPEL HILL AND
 * THE AUTHORS HAVE NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, 
 * ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Please send all BUG REPORTS to <pavel@cs.unc.edu>.
 *
 * The authors may be contacted via:
 *
 * Pavel Krajcevski
 * Dept of Computer Science
 * 201 S Columbia St
 * Frederick P. Brooks, Jr. Computer Science Bldg
 * Chapel Hill, NC 27599-3175
 * USA
 * 
 * <http://gamma.cs.unc.edu/FasTC/>
 */

#include "PVRTCCompressor.h"

#include "Pixel.h"
#include "Image.h"

namespace PVRTCC {

  void Compress(const CompressionJob &dcj,
                bool bTwoBitMode,
                const EWrapMode wrapMode) {
    Image img(dcj.height, dcj.width);
    uint32 nPixels = dcj.height * dcj.width;
    for(uint32 i = 0; i < nPixels; i++) {
      // Assume block stream order (whyyyy)
      uint32 blockIdx = i / 16;
      uint32 blockWidth = dcj.width / 4;
      uint32 blockX = blockIdx % blockWidth;
      uint32 blockY = blockIdx / blockWidth;

      uint32 x = blockX * 4 + (i % 4);
      uint32 y = blockY * 4 + (i % 16) / 4;

      const uint32 *pixels = reinterpret_cast<const uint32 *>(dcj.inBuf);
      img(x, y).UnpackRGBA(pixels[i]);      
    }

    Image original = img;
    img.DebugOutput("Original");

    // Downscale it using anisotropic diffusion based scheme in order to preserve
    // image features, then reupscale and compute deltas. Use deltas to generate
    // initial A & B images followed by modulation data.
    img.ContentAwareDownscale(1, 1, eWrapMode_Wrap, true);
    img.DebugOutput("DownscaledOnce");
    img.ContentAwareDownscale(1, 1, eWrapMode_Wrap, false);
    img.DebugOutput("DownscaledTwice");

    Image downscaled = img;

    // Upscale it again
    img.BilinearUpscale(2, 2, eWrapMode_Wrap);

    img.DebugOutput("Reconstruction");

    // Compute difference...
    Image difference = img;
    for(uint32 j = 0; j < dcj.height; j++) {
      for(uint32 i = 0; i < dcj.width; i++) {
        for(uint32 c = 0; c < 4; c++) {
          difference(i, j).Component(c) -= img(i, j).Component(c);
        }
      }
    }
  }

}  // namespace PVRTCC