/*
  * 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
  */
 
 /**
  * Discrete wavelet transform
  * @file
  * @author Kamil Nowosad
  */
 
 #include "j2k_dwt.h"
 

 static const float scale97[] = {1.625786, 1.230174};

 
 static inline void extend53(int *p, int i0, int i1)
 {
     p[i0 - 1] = p[i0 + 1];
     p[i1    ] = p[i1 - 2];
     p[i0 - 2] = p[i0 + 2];
     p[i1 + 1] = p[i1 - 3];
 }
 
 static inline void extend97(float *p, int i0, int i1)
 {
     int i;
 
     for (i = 1; i <= 4; i++){
         p[i0 - i] = p[i0 + i];
         p[i1 + i - 1] = p[i1 - i - 1];
     }
 }
 
 static void sd_1d53(int *p, int i0, int i1)
 {
     int i;
 
     if (i1 == i0 + 1)
         return;
 
     extend53(p, i0, i1);
 
     for (i = (i0+1)/2 - 1; i < (i1+1)/2; i++)
         p[2*i+1] -= (p[2*i] + p[2*i+2]) >> 1;
     for (i = (i0+1)/2; i < (i1+1)/2; i++)
         p[2*i] += (p[2*i-1] + p[2*i+1] + 2) >> 2;
 }
 
 static void dwt_encode53(DWTContext *s, int *t)
 {
     int lev,
         w = s->linelen[s->ndeclevels-1][0];
     int *line = s->linebuf;
     line += 3;
 
     for (lev = s->ndeclevels-1; lev >= 0; lev--){
         int lh = s->linelen[lev][0],
             lv = s->linelen[lev][1],
             mh = s->mod[lev][0],
             mv = s->mod[lev][1],
             lp;
         int *l;
 
         // HOR_SD
         l = line + mh;
         for (lp = 0; lp < lv; lp++){
             int i, j = 0;
 
             for (i = 0; i < lh; i++)
                 l[i] = t[w*lp + i];
 
             sd_1d53(line, mh, mh + lh);
 
             // copy back and deinterleave
             for (i =   mh; i < lh; i+=2, j++)
                 t[w*lp + j] = l[i];
             for (i = 1-mh; i < lh; i+=2, j++)
                 t[w*lp + j] = l[i];
         }
 
         // VER_SD
         l = line + mv;
         for (lp = 0; lp < lh; lp++) {
             int i, j = 0;
 
             for (i = 0; i < lv; i++)
                 l[i] = t[w*i + lp];
 
             sd_1d53(line, mv, mv + lv);
 
             // copy back and deinterleave
             for (i =   mv; i < lv; i+=2, j++)
                 t[w*j + lp] = l[i];
             for (i = 1-mv; i < lv; i+=2, j++)
                 t[w*j + lp] = l[i];
         }
     }
 }
 
 static void sd_1d97(float *p, int i0, int i1)
 {
     int i;
 
     if (i1 == i0 + 1)
         return;
 
     extend97(p, i0, i1);
     i0++; i1++;
 
     for (i = i0/2 - 2; i < i1/2 + 1; i++)
         p[2*i+1] -= 1.586134 * (p[2*i] + p[2*i+2]);
     for (i = i0/2 - 1; i < i1/2 + 1; i++)
         p[2*i] -= 0.052980 * (p[2*i-1] + p[2*i+1]);
     for (i = i0/2 - 1; i < i1/2; i++)
         p[2*i+1] += 0.882911 * (p[2*i] + p[2*i+2]);
     for (i = i0/2; i < i1/2; i++)
         p[2*i] += 0.443506 * (p[2*i-1] + p[2*i+1]);
 }
 
 static void dwt_encode97(DWTContext *s, int *t)
 {
     int lev,
         w = s->linelen[s->ndeclevels-1][0];
     float *line = s->linebuf;
     line += 5;
 
     for (lev = s->ndeclevels-1; lev >= 0; lev--){
         int lh = s->linelen[lev][0],
             lv = s->linelen[lev][1],
             mh = s->mod[lev][0],
             mv = s->mod[lev][1],
             lp;
         float *l;
 
         // HOR_SD
         l = line + mh;
         for (lp = 0; lp < lv; lp++){
             int i, j = 0;
 
             for (i = 0; i < lh; i++)
                 l[i] = t[w*lp + i];
 
             sd_1d97(line, mh, mh + lh);
 
             // copy back and deinterleave
             for (i =   mh; i < lh; i+=2, j++)
                 t[w*lp + j] = scale97[mh] * l[i] / 2;
             for (i = 1-mh; i < lh; i+=2, j++)
                 t[w*lp + j] = scale97[mh] * l[i] / 2;
         }
 
         // VER_SD
         l = line + mv;
         for (lp = 0; lp < lh; lp++) {
             int i, j = 0;
 
             for (i = 0; i < lv; i++)
                 l[i] = t[w*i + lp];
 
             sd_1d97(line, mv, mv + lv);
 
             // copy back and deinterleave
             for (i =   mv; i < lv; i+=2, j++)
                 t[w*j + lp] = scale97[mv] * l[i] / 2;
             for (i = 1-mv; i < lv; i+=2, j++)
                 t[w*j + lp] = scale97[mv] * l[i] / 2;
         }
     }
 }
 
 static void sr_1d53(int *p, int i0, int i1)
 {
     int i;
 
     if (i1 == i0 + 1)
         return;
 
     extend53(p, i0, i1);
 
     for (i = i0/2; i < i1/2 + 1; i++)
         p[2*i] -= (p[2*i-1] + p[2*i+1] + 2) >> 2;
     for (i = i0/2; i < i1/2; i++)
         p[2*i+1] += (p[2*i] + p[2*i+2]) >> 1;
 }
 
 static void dwt_decode53(DWTContext *s, int *t)
 {
     int lev,
         w = s->linelen[s->ndeclevels-1][0];
     int *line = s->linebuf;
     line += 3;
 
     for (lev = 0; lev < s->ndeclevels; lev++){
         int lh = s->linelen[lev][0],
             lv = s->linelen[lev][1],
             mh = s->mod[lev][0],
             mv = s->mod[lev][1],
             lp;
         int *l;
 
         // HOR_SD
         l = line + mh;
         for (lp = 0; lp < lv; lp++){
             int i, j = 0;
             // copy with interleaving
             for (i =   mh; i < lh; i+=2, j++)
                 l[i] = t[w*lp + j];
             for (i = 1-mh; i < lh; i+=2, j++)
                 l[i] = t[w*lp + j];
 
             sr_1d53(line, mh, mh + lh);
 
             for (i = 0; i < lh; i++)
                 t[w*lp + i] = l[i];
         }
 
         // VER_SD
         l = line + mv;
         for (lp = 0; lp < lh; lp++){
             int i, j = 0;
             // copy with interleaving
             for (i =   mv; i < lv; i+=2, j++)
                 l[i] = t[w*j + lp];
             for (i = 1-mv; i < lv; i+=2, j++)
                 l[i] = t[w*j + lp];
 
             sr_1d53(line, mv, mv + lv);
 
             for (i = 0; i < lv; i++)
                 t[w*i + lp] = l[i];
         }
     }
 }
 
 static void sr_1d97(float *p, int i0, int i1)
 {
     int i;
 
     if (i1 == i0 + 1)
         return;
 
     extend97(p, i0, i1);
 
     for (i = i0/2 - 1; i < i1/2 + 2; i++)
         p[2*i] -= 0.443506 * (p[2*i-1] + p[2*i+1]);
     for (i = i0/2 - 1; i < i1/2 + 1; i++)
         p[2*i+1] -= 0.882911 * (p[2*i] + p[2*i+2]);
     for (i = i0/2; i < i1/2 + 1; i++)
         p[2*i] += 0.052980 * (p[2*i-1] + p[2*i+1]);
     for (i = i0/2; i < i1/2; i++)
         p[2*i+1] += 1.586134 * (p[2*i] + p[2*i+2]);
 }
 
 static void dwt_decode97(DWTContext *s, int *t)
 {
     int lev,
         w = s->linelen[s->ndeclevels-1][0];
     float *line = s->linebuf;
     line += 5;
 
     for (lev = 0; lev < s->ndeclevels; lev++){
         int lh = s->linelen[lev][0],
             lv = s->linelen[lev][1],
             mh = s->mod[lev][0],
             mv = s->mod[lev][1],
             lp;
         float *l;
 
         // HOR_SD
         l = line + mh;
         for (lp = 0; lp < lv; lp++){
             int i, j = 0;
             // copy with interleaving
             for (i =   mh; i < lh; i+=2, j++)
                 l[i] = scale97[1-mh] * t[w*lp + j];
             for (i = 1-mh; i < lh; i+=2, j++)
                 l[i] = scale97[1-mh] * t[w*lp + j];
 
             sr_1d97(line, mh, mh + lh);
 
             for (i = 0; i < lh; i++)
                 t[w*lp + i] = l[i];
         }
 
         // VER_SD
         l = line + mv;
         for (lp = 0; lp < lh; lp++){
             int i, j = 0;
             // copy with interleaving
             for (i =   mv; i < lv; i+=2, j++)
                 l[i] = scale97[1-mv] * t[w*j + lp];
             for (i = 1-mv; i < lv; i+=2, j++)
                 l[i] = scale97[1-mv] * t[w*j + lp];
 
             sr_1d97(line, mv, mv + lv);
 
             for (i = 0; i < lv; i++)
                 t[w*i + lp] = l[i];
         }
     }
 }
 
 int ff_j2k_dwt_init(DWTContext *s, uint16_t border[2][2], int decomp_levels, int type)
 {
     int i, j, lev = decomp_levels, maxlen,
         b[2][2];
 

     if ((unsigned)decomp_levels >= FF_DWT_MAX_DECLVLS)

         return AVERROR_INVALIDDATA;

     s->ndeclevels = decomp_levels;
     s->type = type;
 
     for (i = 0; i < 2; i++)
         for(j = 0; j < 2; j++)
             b[i][j] = border[i][j];
 
     maxlen = FFMAX(b[0][1] - b[0][0],
                    b[1][1] - b[1][0]);
 
     while(--lev >= 0){
         for (i = 0; i < 2; i++){
             s->linelen[lev][i] = b[i][1] - b[i][0];
             s->mod[lev][i] = b[i][0] & 1;
             for (j = 0; j < 2; j++)
                 b[i][j] = (b[i][j] + 1) >> 1;
         }
     }
     if (type == FF_DWT97)
         s->linebuf = av_malloc((maxlen + 12) * sizeof(float));
     else if (type == FF_DWT53)
         s->linebuf = av_malloc((maxlen + 6) * sizeof(int));
     else
         return -1;
 
     if (!s->linebuf)
         return AVERROR(ENOMEM);
 
     return 0;
 }
 
 int ff_j2k_dwt_encode(DWTContext *s, int *t)
 {
     switch(s->type){
         case FF_DWT97:
             dwt_encode97(s, t); break;
         case FF_DWT53:
             dwt_encode53(s, t); break;
         default:
             return -1;
     }
     return 0;
 }
 
 int ff_j2k_dwt_decode(DWTContext *s, int *t)
 {
     switch(s->type){
         case FF_DWT97:
             dwt_decode97(s, t); break;
         case FF_DWT53:
             dwt_decode53(s, t); break;
         default:
             return -1;
     }
     return 0;
 }
 
 void ff_j2k_dwt_destroy(DWTContext *s)
 {
     av_freep(&s->linebuf);
 }