/*
  * Lossless video DSP utils
  *
  * 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
  */
 #include "avcodec.h"
 #include "lossless_videodsp.h"

 #include "libavcodec/mathops.h"

 
 static void add_int16_c(uint16_t *dst, const uint16_t *src, unsigned mask, int w){
     long i;
     unsigned long pw_lsb = (mask >> 1) * 0x0001000100010001ULL;
     unsigned long pw_msb = pw_lsb +  0x0001000100010001ULL;
     for (i = 0; i <= w - (int)sizeof(long)/2; i += sizeof(long)/2) {
         long a = *(long*)(src+i);
         long b = *(long*)(dst+i);
         *(long*)(dst+i) = ((a&pw_lsb) + (b&pw_lsb)) ^ ((a^b)&pw_msb);
     }
     for(; i<w; i++)
         dst[i] = (dst[i] + src[i]) & mask;
 }
 
 static void diff_int16_c(uint16_t *dst, const uint16_t *src1, const uint16_t *src2, unsigned mask, int w){
     long i;
 #if !HAVE_FAST_UNALIGNED
     if((long)src2 & (sizeof(long)-1)){

         for(i=0; i+3<w; i+=4){

             dst[i+0] = (src1[i+0]-src2[i+0]) & mask;
             dst[i+1] = (src1[i+1]-src2[i+1]) & mask;
             dst[i+2] = (src1[i+2]-src2[i+2]) & mask;
             dst[i+3] = (src1[i+3]-src2[i+3]) & mask;
         }
     }else
 #endif
     {
         unsigned long pw_lsb = (mask >> 1) * 0x0001000100010001ULL;
         unsigned long pw_msb = pw_lsb +  0x0001000100010001ULL;
 
         for (i = 0; i <= w - (int)sizeof(long)/2; i += sizeof(long)/2) {
             long a = *(long*)(src1+i);
             long b = *(long*)(src2+i);
             *(long*)(dst+i) = ((a|pw_msb) - (b&pw_lsb)) ^ ((a^b^pw_msb)&pw_msb);
         }
     }
     for (; i<w; i++)
         dst[i] = (src1[i] - src2[i]) & mask;
 }
 

 static void add_hfyu_median_prediction_int16_c(uint16_t *dst, const uint16_t *src, const uint16_t *diff, unsigned mask, int w, int *left, int *left_top){
     int i;
     uint16_t l, lt;
 
     l  = *left;
     lt = *left_top;
 
     for(i=0; i<w; i++){
         l  = (mid_pred(l, src[i], (l + src[i] - lt) & mask) + diff[i]) & mask;
         lt = src[i];
         dst[i] = l;
     }
 
     *left     = l;
     *left_top = lt;
 }
 

 static void sub_hfyu_median_prediction_int16_c(uint16_t *dst, const uint16_t *src1, const uint16_t *src2, unsigned mask, int w, int *left, int *left_top){
     int i;
     uint16_t l, lt;
 
     l  = *left;
     lt = *left_top;
 
     for(i=0; i<w; i++){
         const int pred = mid_pred(l, src1[i], (l + src1[i] - lt) & mask);
         lt = src1[i];
         l  = src2[i];
         dst[i] = (l - pred) & mask;
     }
 
     *left     = l;
     *left_top = lt;
 }
 

 static int add_hfyu_left_prediction_int16_c(uint16_t *dst, const uint16_t *src, unsigned mask, int w, unsigned acc){

     int i;
 
     for(i=0; i<w-1; i++){
         acc+= src[i];
         dst[i]= acc & mask;
         i++;
         acc+= src[i];
         dst[i]= acc & mask;
     }
 
     for(; i<w; i++){
         acc+= src[i];
         dst[i]= acc & mask;
     }
 
     return acc;
 }
 
 

 void ff_llviddsp_init(LLVidDSPContext *c, AVCodecContext *avctx)

 {
     c->add_int16 = add_int16_c;
     c->diff_int16= diff_int16_c;

     c->add_hfyu_left_prediction_int16   = add_hfyu_left_prediction_int16_c;

     c->add_hfyu_median_prediction_int16 = add_hfyu_median_prediction_int16_c;

     c->sub_hfyu_median_prediction_int16 = sub_hfyu_median_prediction_int16_c;

 
     if (ARCH_X86)

         ff_llviddsp_init_x86(c, avctx);

 }