libavcodec/jpeg2000dwt.h

   1 /*
   2  * Discrete wavelet transform
   3  * Copyright (c) 2007 Kamil Nowosad
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef AVCODEC_JPEG2000DWT_H
  23 #define AVCODEC_JPEG2000DWT_H
  24
  25 /**
  26  * @file
  27  * Discrete wavelet transform
  28  */
  29
  30 #include <stdint.h>
  31
  32 #define FF_DWT_MAX_DECLVLS 32 ///< max number of decomposition levels
  33 #define F_LFTG_K      1.230174104914001f
  34 #define F_LFTG_X      0.812893066115961f
  35 #define I_PRESHIFT 8
  36
  37 enum DWTType {
  38     FF_DWT97,
  39     FF_DWT53,
  40     FF_DWT97_INT,
  41     FF_DWT_NB
  42 };
  43
  44 typedef struct DWTContext {
  45     /// line lengths { horizontal, vertical } in consecutive decomposition levels
  46     int linelen[FF_DWT_MAX_DECLVLS][2];
  47     uint8_t mod[FF_DWT_MAX_DECLVLS][2];  ///< coordinates (x0, y0) of decomp. levels mod 2
  48     uint8_t ndeclevels;                  ///< number of decomposition levels
  49     uint8_t type;                        ///< 0 for 9/7; 1 for 5/3
  50     int32_t *i_linebuf;                  ///< int buffer used by transform
  51     float   *f_linebuf;                  ///< float buffer used by transform
  52 } DWTContext;
  53
  54 /**
  55  * Initialize DWT.
  56  * @param s                 DWT context
  57  * @param border            coordinates of transformed region {{x0, x1}, {y0, y1}}
  58  * @param decomp_levels     number of decomposition levels
  59  * @param type              0 for DWT 9/7; 1 for DWT 5/3
  60  */
  61 int ff_jpeg2000_dwt_init(DWTContext *s, int border[2][2],
  62                          int decomp_levels, int type);
  63
  64 int ff_dwt_encode(DWTContext *s, void *t);
  65 int ff_dwt_decode(DWTContext *s, void *t);
  66
  67 void ff_dwt_destroy(DWTContext *s);
  68
  69 #endif /* AVCODEC_JPEG2000DWT_H */