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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 
36 enum DWTType {
37     FF_DWT97,
38     FF_DWT53,
39     FF_DWT97_INT,
40     FF_DWT_NB
41 };
42 
43 typedef struct DWTContext {
44     /// line lengths { horizontal, vertical } in consecutive decomposition levels
45     int linelen[FF_DWT_MAX_DECLVLS][2];
46     uint8_t mod[FF_DWT_MAX_DECLVLS][2];  ///< coordinates (x0, y0) of decomp. levels mod 2
47     uint8_t ndeclevels;                  ///< number of decomposition levels
48     uint8_t type;                        ///< 0 for 9/7; 1 for 5/3
49     int32_t *i_linebuf;                  ///< int buffer used by transform
50     float   *f_linebuf;                  ///< float buffer used by transform
51 } DWTContext;
52 
53 /**
54  * Initialize DWT.
55  * @param s                 DWT context
56  * @param border            coordinates of transformed region {{x0, x1}, {y0, y1}}
57  * @param decomp_levels     number of decomposition levels
58  * @param type              0 for DWT 9/7; 1 for DWT 5/3
59  */
60 int ff_jpeg2000_dwt_init(DWTContext *s, int border[2][2],
61                          int decomp_levels, int type);
62 
63 int ff_dwt_encode(DWTContext *s, void *t);
64 int ff_dwt_decode(DWTContext *s, void *t);
65 
66 void ff_dwt_destroy(DWTContext *s);
67 
68 #endif /* AVCODEC_JPEG2000DWT_H */
69