git.sesse.net Git - vlc/blob - plugins/idct/idct_common.c

   1 /*****************************************************************************
   2  * idct_common.c : common IDCT functions
   3  *****************************************************************************
   4  * Copyright (C) 1999, 2000 VideoLAN
   5  * $Id: idct_common.c,v 1.2 2001/01/15 06:18:23 sam Exp $
   6  *
   7  * Authors: Gaël Hendryckx <jimmy@via.ecp.fr>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include "defs.h"
  28
  29 #include "config.h"
  30 #include "common.h"
  31 #include "threads.h"
  32 #include "mtime.h"
  33
  34 #include "video.h"
  35 #include "video_output.h"
  36
  37 #include "video_decoder.h"
  38
  39 #include "modules.h"
  40
  41 #include "idct.h"
  42
  43 void vdec_SparseIDCT ( vdec_thread_t * p_vdec, dctelem_t * p_block,
  44                        int i_sparse_pos);
  45
  46 /*****************************************************************************
  47  * vdec_SparseIDCT : IDCT function for sparse matrices
  48  *****************************************************************************/
  49 void vdec_SparseIDCT (vdec_thread_t * p_vdec, dctelem_t * p_block,
  50                       int i_sparse_pos)
  51 {
  52     short int val;
  53     int * dp;
  54     int v;
  55     short int * p_dest;
  56     short int * p_source;
  57     int coeff, rr;
  58
  59     /* If DC Coefficient. */
  60     if ( i_sparse_pos == 0 )
  61     {
  62         dp=(int *)p_block;
  63         val=RIGHT_SHIFT((*p_block + 4), 3);
  64         /* Compute int to assign.  This speeds things up a bit */
  65         v = ((val & 0xffff) | (val << 16));
  66         dp[0] = v;     dp[1] = v;     dp[2] = v;     dp[3] = v;
  67         dp[4] = v;     dp[5] = v;     dp[6] = v;     dp[7] = v;
  68         dp[8] = v;     dp[9] = v;     dp[10] = v;    dp[11] = v;
  69         dp[12] = v;    dp[13] = v;    dp[14] = v;    dp[15] = v;
  70         dp[16] = v;    dp[17] = v;    dp[18] = v;    dp[19] = v;
  71         dp[20] = v;    dp[21] = v;    dp[22] = v;    dp[23] = v;
  72         dp[24] = v;    dp[25] = v;    dp[26] = v;    dp[27] = v;
  73         dp[28] = v;    dp[29] = v;    dp[30] = v;    dp[31] = v;
  74         return;
  75     }
  76     /* Some other coefficient. */
  77     p_dest = (s16*)p_block;
  78     p_source = (s16*)&p_vdec->p_pre_idct[i_sparse_pos];
  79     coeff = (int)p_dest[i_sparse_pos];
  80     for( rr=0 ; rr < 4 ; rr++ )
  81     {
  82         p_dest[0] = (p_source[0] * coeff) >> SPARSE_SCALE_FACTOR;
  83         p_dest[1] = (p_source[1] * coeff) >> SPARSE_SCALE_FACTOR;
  84         p_dest[2] = (p_source[2] * coeff) >> SPARSE_SCALE_FACTOR;
  85         p_dest[3] = (p_source[3] * coeff) >> SPARSE_SCALE_FACTOR;
  86         p_dest[4] = (p_source[4] * coeff) >> SPARSE_SCALE_FACTOR;
  87         p_dest[5] = (p_source[5] * coeff) >> SPARSE_SCALE_FACTOR;
  88         p_dest[6] = (p_source[6] * coeff) >> SPARSE_SCALE_FACTOR;
  89         p_dest[7] = (p_source[7] * coeff) >> SPARSE_SCALE_FACTOR;
  90         p_dest[8] = (p_source[8] * coeff) >> SPARSE_SCALE_FACTOR;
  91         p_dest[9] = (p_source[9] * coeff) >> SPARSE_SCALE_FACTOR;
  92         p_dest[10] = (p_source[10] * coeff) >> SPARSE_SCALE_FACTOR;
  93         p_dest[11] = (p_source[11] * coeff) >> SPARSE_SCALE_FACTOR;
  94         p_dest[12] = (p_source[12] * coeff) >> SPARSE_SCALE_FACTOR;
  95         p_dest[13] = (p_source[13] * coeff) >> SPARSE_SCALE_FACTOR;
  96         p_dest[14] = (p_source[14] * coeff) >> SPARSE_SCALE_FACTOR;
  97         p_dest[15] = (p_source[15] * coeff) >> SPARSE_SCALE_FACTOR;
  98         p_dest += 16;
  99         p_source += 16;
 100     }
 101     return;
 102 }
 103