/*
  * Copyright (C) 2004 the ffmpeg project
  *

  * 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

  */
 
 /**

  * @file

  * Standard C DSP-oriented functions cribbed from the original VP3

  * source code.
  */
 
 #include "avcodec.h"

 #include "dsputil.h"

 
 #define IdctAdjustBeforeShift 8
 #define xC1S7 64277
 #define xC2S6 60547
 #define xC3S5 54491
 #define xC4S4 46341
 #define xC5S3 36410
 #define xC6S2 25080
 #define xC7S1 12785
 

 #define M(a,b) (((a) * (b))>>16)
 

 static av_always_inline void idct(uint8_t *dst, int stride, int16_t *input, int type)

 {

     int16_t *ip = input;

     int A, B, C, D, Ad, Bd, Cd, Dd, E, F, G, H;
     int Ed, Gd, Add, Bdd, Fd, Hd;

     int i;

     /* Inverse DCT on the rows now */
     for (i = 0; i < 8; i++) {
         /* Check for non-zero values */
         if ( ip[0] | ip[1] | ip[2] | ip[3] | ip[4] | ip[5] | ip[6] | ip[7] ) {

             A = M(xC1S7, ip[1]) + M(xC7S1, ip[7]);
             B = M(xC7S1, ip[1]) - M(xC1S7, ip[7]);
             C = M(xC3S5, ip[3]) + M(xC5S3, ip[5]);
             D = M(xC3S5, ip[5]) - M(xC5S3, ip[3]);

             Ad = M(xC4S4, (A - C));
             Bd = M(xC4S4, (B - D));

             Cd = A + C;
             Dd = B + D;

             E = M(xC4S4, (ip[0] + ip[4]));
             F = M(xC4S4, (ip[0] - ip[4]));

             G = M(xC2S6, ip[2]) + M(xC6S2, ip[6]);
             H = M(xC6S2, ip[2]) - M(xC2S6, ip[6]);

             Ed = E - G;
             Gd = E + G;

             Add = F + Ad;
             Bdd = Bd - H;

             Fd = F - Ad;
             Hd = Bd + H;

 
             /*  Final sequence of operations over-write original inputs. */

             ip[0] = Gd + Cd ;
             ip[7] = Gd - Cd ;

             ip[1] = Add + Hd;
             ip[2] = Add - Hd;

             ip[3] = Ed + Dd ;
             ip[4] = Ed - Dd ;

             ip[5] = Fd + Bdd;
             ip[6] = Fd - Bdd;

         }
 
         ip += 8;            /* next row */
     }

     ip = input;

 
     for ( i = 0; i < 8; i++) {
         /* Check for non-zero values (bitwise or faster than ||) */

         if ( ip[1 * 8] | ip[2 * 8] | ip[3 * 8] |

              ip[4 * 8] | ip[5 * 8] | ip[6 * 8] | ip[7 * 8] ) {
 

             A = M(xC1S7, ip[1*8]) + M(xC7S1, ip[7*8]);
             B = M(xC7S1, ip[1*8]) - M(xC1S7, ip[7*8]);
             C = M(xC3S5, ip[3*8]) + M(xC5S3, ip[5*8]);
             D = M(xC3S5, ip[5*8]) - M(xC5S3, ip[3*8]);

             Ad = M(xC4S4, (A - C));
             Bd = M(xC4S4, (B - D));

             Cd = A + C;
             Dd = B + D;

             E = M(xC4S4, (ip[0*8] + ip[4*8])) + 8;
             F = M(xC4S4, (ip[0*8] - ip[4*8])) + 8;
 
             if(type==1){  //HACK
                 E += 16*128;
                 F += 16*128;
             }

             G = M(xC2S6, ip[2*8]) + M(xC6S2, ip[6*8]);
             H = M(xC6S2, ip[2*8]) - M(xC2S6, ip[6*8]);

             Ed = E - G;
             Gd = E + G;

             Add = F + Ad;
             Bdd = Bd - H;

             Fd = F - Ad;
             Hd = Bd + H;

 
             /* Final sequence of operations over-write original inputs. */

             if(type==0){

                 ip[0*8] = (Gd + Cd )  >> 4;
                 ip[7*8] = (Gd - Cd )  >> 4;

                 ip[1*8] = (Add + Hd ) >> 4;
                 ip[2*8] = (Add - Hd ) >> 4;

                 ip[3*8] = (Ed + Dd )  >> 4;
                 ip[4*8] = (Ed - Dd )  >> 4;

                 ip[5*8] = (Fd + Bdd ) >> 4;
                 ip[6*8] = (Fd - Bdd ) >> 4;

             }else if(type==1){

                 dst[0*stride] = av_clip_uint8((Gd + Cd )  >> 4);
                 dst[7*stride] = av_clip_uint8((Gd - Cd )  >> 4);

                 dst[1*stride] = av_clip_uint8((Add + Hd ) >> 4);
                 dst[2*stride] = av_clip_uint8((Add - Hd ) >> 4);

                 dst[3*stride] = av_clip_uint8((Ed + Dd )  >> 4);
                 dst[4*stride] = av_clip_uint8((Ed - Dd )  >> 4);

                 dst[5*stride] = av_clip_uint8((Fd + Bdd ) >> 4);
                 dst[6*stride] = av_clip_uint8((Fd - Bdd ) >> 4);

             }else{

                 dst[0*stride] = av_clip_uint8(dst[0*stride] + ((Gd + Cd )  >> 4));
                 dst[7*stride] = av_clip_uint8(dst[7*stride] + ((Gd - Cd )  >> 4));

                 dst[1*stride] = av_clip_uint8(dst[1*stride] + ((Add + Hd ) >> 4));
                 dst[2*stride] = av_clip_uint8(dst[2*stride] + ((Add - Hd ) >> 4));

                 dst[3*stride] = av_clip_uint8(dst[3*stride] + ((Ed + Dd )  >> 4));
                 dst[4*stride] = av_clip_uint8(dst[4*stride] + ((Ed - Dd )  >> 4));

                 dst[5*stride] = av_clip_uint8(dst[5*stride] + ((Fd + Bdd ) >> 4));
                 dst[6*stride] = av_clip_uint8(dst[6*stride] + ((Fd - Bdd ) >> 4));

             }

 
         } else {

             if(type==0){

                 ip[0*8] =
                 ip[1*8] =
                 ip[2*8] =
                 ip[3*8] =
                 ip[4*8] =
                 ip[5*8] =

                 ip[6*8] =
                 ip[7*8] = ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20);
             }else if(type==1){
                 dst[0*stride]=
                 dst[1*stride]=
                 dst[2*stride]=
                 dst[3*stride]=
                 dst[4*stride]=
                 dst[5*stride]=
                 dst[6*stride]=

                 dst[7*stride]= av_clip_uint8(128 + ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20));

             }else{
                 if(ip[0*8]){
                     int v= ((xC4S4 * ip[0*8] + (IdctAdjustBeforeShift<<16))>>20);

                     dst[0*stride] = av_clip_uint8(dst[0*stride] + v);
                     dst[1*stride] = av_clip_uint8(dst[1*stride] + v);
                     dst[2*stride] = av_clip_uint8(dst[2*stride] + v);
                     dst[3*stride] = av_clip_uint8(dst[3*stride] + v);
                     dst[4*stride] = av_clip_uint8(dst[4*stride] + v);
                     dst[5*stride] = av_clip_uint8(dst[5*stride] + v);
                     dst[6*stride] = av_clip_uint8(dst[6*stride] + v);
                     dst[7*stride] = av_clip_uint8(dst[7*stride] + v);

                 }
             }

         }
 
         ip++;            /* next column */

         dst++;

     }
 }

 
 void ff_vp3_idct_c(DCTELEM *block/* align 16*/){
     idct(NULL, 0, block, 0);
 }

 void ff_vp3_idct_put_c(uint8_t *dest/*align 8*/, int line_size, DCTELEM *block/*align 16*/){
     idct(dest, line_size, block, 1);
 }
 
 void ff_vp3_idct_add_c(uint8_t *dest/*align 8*/, int line_size, DCTELEM *block/*align 16*/){
     idct(dest, line_size, block, 2);
 }

 void ff_vp3_idct_dc_add_c(uint8_t *dest/*align 8*/, int line_size, const DCTELEM *block/*align 16*/){

     int i, dc = (block[0] + 15) >> 5;

 
     for(i = 0; i < 8; i++){

         dest[0] = av_clip_uint8(dest[0] + dc);
         dest[1] = av_clip_uint8(dest[1] + dc);
         dest[2] = av_clip_uint8(dest[2] + dc);
         dest[3] = av_clip_uint8(dest[3] + dc);
         dest[4] = av_clip_uint8(dest[4] + dc);
         dest[5] = av_clip_uint8(dest[5] + dc);
         dest[6] = av_clip_uint8(dest[6] + dc);
         dest[7] = av_clip_uint8(dest[7] + dc);

         dest += line_size;
     }
 }
 

 void ff_vp3_v_loop_filter_c(uint8_t *first_pixel, int stride, int *bounding_values)
 {
     unsigned char *end;
     int filter_value;
     const int nstride= -stride;
 
     for (end= first_pixel + 8; first_pixel < end; first_pixel++) {
         filter_value =
             (first_pixel[2 * nstride] - first_pixel[ stride])
          +3*(first_pixel[0          ] - first_pixel[nstride]);
         filter_value = bounding_values[(filter_value + 4) >> 3];
         first_pixel[nstride] = av_clip_uint8(first_pixel[nstride] + filter_value);
         first_pixel[0] = av_clip_uint8(first_pixel[0] - filter_value);
     }
 }
 
 void ff_vp3_h_loop_filter_c(uint8_t *first_pixel, int stride, int *bounding_values)
 {
     unsigned char *end;
     int filter_value;
 
     for (end= first_pixel + 8*stride; first_pixel != end; first_pixel += stride) {
         filter_value =
             (first_pixel[-2] - first_pixel[ 1])
          +3*(first_pixel[ 0] - first_pixel[-1]);
         filter_value = bounding_values[(filter_value + 4) >> 3];
         first_pixel[-1] = av_clip_uint8(first_pixel[-1] + filter_value);
         first_pixel[ 0] = av_clip_uint8(first_pixel[ 0] - filter_value);
     }
 }