text: /*
   * Discrete wavelet transform
   * Copyright (c) 2007 Kamil Nowosad
   *
   * This file is part of FFmpeg.
   *
   * FFmpeg is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * FFmpeg is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with FFmpeg; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  #ifndef AVCODEC_JPEG2000DWT_H
  #define AVCODEC_JPEG2000DWT_H
  
  /**
   * @file
   * Discrete wavelet transform
   */
  
  #include <stdint.h>
  
  #define FF_DWT_MAX_DECLVLS 32 ///< max number of decomposition levels
  #define F_LFTG_K      1.230174104914001f
  #define F_LFTG_X      0.812893066115961f
  
  enum DWTType {
      FF_DWT97,
      FF_DWT53,
      FF_DWT97_INT,
      FF_DWT_NB
  };
  
  typedef struct DWTContext {
      /// line lengths { horizontal, vertical } in consecutive decomposition levels
      int linelen[FF_DWT_MAX_DECLVLS][2];
      uint8_t mod[FF_DWT_MAX_DECLVLS][2];  ///< coordinates (x0, y0) of decomp. levels mod 2
      uint8_t ndeclevels;                  ///< number of decomposition levels
      uint8_t type;                        ///< 0 for 9/7; 1 for 5/3
      int32_t *i_linebuf;                  ///< int buffer used by transform
      float   *f_linebuf;                  ///< float buffer used by transform
  } DWTContext;
  
  /**
   * Initialize DWT.
   * @param s                 DWT context
   * @param border            coordinates of transformed region {{x0, x1}, {y0, y1}}
   * @param decomp_levels     number of decomposition levels
   * @param type              0 for DWT 9/7; 1 for DWT 5/3
   */
  int ff_jpeg2000_dwt_init(DWTContext *s, int border[2][2],
                           int decomp_levels, int type);
  
  int ff_dwt_encode(DWTContext *s, void *t);
  int ff_dwt_decode(DWTContext *s, void *t);
  
  void ff_dwt_destroy(DWTContext *s);
  
  #endif /* AVCODEC_JPEG2000DWT_H */
  