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revision 1.6, Sun Dec 15 01:21:12 2002 UTC revision 1.7, Sat Feb 15 15:22:19 2003 UTC
# Line 1  Line 1 
1  /**************************************************************************  /**************************************************************************
2   *   *
3   *      XVID MPEG-4 VIDEO CODEC   *      XVID MPEG-4 VIDEO CODEC
4   *      - quantization/dequantization -   *      quantization/dequantization
5   *   *
6   *  This file is part of XviD, a free MPEG-4 video encoder/decoder   *      This program is an implementation of a part of one or more MPEG-4
7     *      Video tools as specified in ISO/IEC 14496-2 standard.  Those intending
8     *      to use this software module in hardware or software products are
9     *      advised that its use may infringe existing patents or copyrights, and
10     *      any such use would be at such party's own risk.  The original
11     *      developer of this software module and his/her company, and subsequent
12     *      editors and their companies, will have no liability for use of this
13     *      software or modifications or derivatives thereof.
14   *   *
15   *  XviD is free software; you can redistribute it and/or modify it   *      This program is free software; you can redistribute it and/or modify
16   *  under the terms of the GNU General Public License as published by   *      it under the terms of the GNU General Public License as published by
17   *  the Free Software Foundation; either version 2 of the License, or   *  the Free Software Foundation; either version 2 of the License, or
18   *  (at your option) any later version.   *  (at your option) any later version.
19   *   *
# Line 17  Line 24 
24   *   *
25   *  You should have received a copy of the GNU General Public License   *  You should have received a copy of the GNU General Public License
26   *  along with this program; if not, write to the Free Software   *  along with this program; if not, write to the Free Software
27   *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA   *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
28   *   *
29   *  Under section 8 of the GNU General Public License, the copyright   *************************************************************************/
30   *  holders of XVID explicitly forbid distribution in the following  
31   *  countries:  /**************************************************************************
  *  
  *    - Japan  
  *    - United States of America  
  *  
  *  Linking XviD statically or dynamically with other modules is making a  
  *  combined work based on XviD.  Thus, the terms and conditions of the  
  *  GNU General Public License cover the whole combination.  
  *  
  *  As a special exception, the copyright holders of XviD give you  
  *  permission to link XviD with independent modules that communicate with  
  *  XviD solely through the VFW1.1 and DShow interfaces, regardless of the  
  *  license terms of these independent modules, and to copy and distribute  
  *  the resulting combined work under terms of your choice, provided that  
  *  every copy of the combined work is accompanied by a complete copy of  
  *  the source code of XviD (the version of XviD used to produce the  
  *  combined work), being distributed under the terms of the GNU General  
  *  Public License plus this exception.  An independent module is a module  
  *  which is not derived from or based on XviD.  
  *  
  *  Note that people who make modified versions of XviD are not obligated  
  *  to grant this special exception for their modified versions; it is  
  *  their choice whether to do so.  The GNU General Public License gives  
  *  permission to release a modified version without this exception; this  
  *  exception also makes it possible to release a modified version which  
  *  carries forward this exception.  
32   *   *
33   * $Id$   *      History:
34     *
35     *  26.12.2001  dequant_inter bug fix
36     *      22.12.2001      clamp dequant output to [-2048,2047]
37     *  19.11.2001  quant_inter now returns sum of abs. coefficient values
38     *      02.11.2001      added const to function args <pross@cs.rmit.edu.au>
39     *      28.10.2001      total rewrite <pross@cs.rmit.edu.au>
40   *   *
41   *************************************************************************/   *************************************************************************/
42    
43    #include "../global.h"
44  #include "quant_h263.h"  #include "quant_h263.h"
45    
46  /*      mutliply+shift division table  /*      mutliply+shift division table
# Line 73  Line 62 
62    
63    
64    
65  #define DIV_DIV(a, b) ((a)>0) ? ((a)+((b)>>1))/(b) : ((a)-((b)>>1))/(b)  // function pointers
   
 /* function pointers */  
66  quanth263_intraFuncPtr quant_intra;  quanth263_intraFuncPtr quant_intra;
67  quanth263_intraFuncPtr dequant_intra;  quanth263_intraFuncPtr dequant_intra;
68    
# Line 95  Line 82 
82                            const uint32_t dcscalar)                            const uint32_t dcscalar)
83  {  {
84          const uint32_t mult = multipliers[quant];          const uint32_t mult = multipliers[quant];
85          const uint16_t quant_m_2 = (uint16_t)(quant << 1);          const uint16_t quant_m_2 = quant << 1;
86          uint32_t i;          uint32_t i;
87    
88          coeff[0] = (int16_t)(DIV_DIV(data[0], (int32_t) dcscalar));          coeff[0] = DIV_DIV(data[0], (int32_t) dcscalar);
89    
90          for (i = 1; i < 64; i++) {          for (i = 1; i < 64; i++) {
91                  int16_t acLevel = data[i];                  int16_t acLevel = data[i];
# Line 109  Line 96 
96                                  coeff[i] = 0;                                  coeff[i] = 0;
97                                  continue;                                  continue;
98                          }                          }
99                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);                          acLevel = (acLevel * mult) >> SCALEBITS;
100                          coeff[i] = -acLevel;                          coeff[i] = -acLevel;
101                  } else {                  } else {
102                          if (acLevel < quant_m_2) {                          if (acLevel < quant_m_2) {
103                                  coeff[i] = 0;                                  coeff[i] = 0;
104                                  continue;                                  continue;
105                          }                          }
106                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);                          acLevel = (acLevel * mult) >> SCALEBITS;
107                          coeff[i] = acLevel;                          coeff[i] = acLevel;
108                  }                  }
109          }          }
# Line 132  Line 119 
119                            const uint32_t quant)                            const uint32_t quant)
120  {  {
121          const uint32_t mult = multipliers[quant];          const uint32_t mult = multipliers[quant];
122          const uint16_t quant_m_2 = (uint16_t)(quant << 1);          const uint16_t quant_m_2 = quant << 1;
123          const uint16_t quant_d_2 = (uint16_t)(quant >> 1);          const uint16_t quant_d_2 = quant >> 1;
124          int sum = 0;          int sum = 0;
125          uint32_t i;          uint32_t i;
126    
# Line 147  Line 134 
134                                  continue;                                  continue;
135                          }                          }
136    
137                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);                          acLevel = (acLevel * mult) >> SCALEBITS;
138                          sum += acLevel;         /* sum += |acLevel| */                          sum += acLevel;         // sum += |acLevel|
139                          coeff[i] = -acLevel;                          coeff[i] = -acLevel;
140                  } else {                  } else {
141                          acLevel -= quant_d_2;                          acLevel -= quant_d_2;
# Line 156  Line 143 
143                                  coeff[i] = 0;                                  coeff[i] = 0;
144                                  continue;                                  continue;
145                          }                          }
146                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);                          acLevel = (acLevel * mult) >> SCALEBITS;
147                          sum += acLevel;                          sum += acLevel;
148                          coeff[i] = acLevel;                          coeff[i] = acLevel;
149                  }                  }
# Line 179  Line 166 
166          const int32_t quant_add = (quant & 1 ? quant : quant - 1);          const int32_t quant_add = (quant & 1 ? quant : quant - 1);
167          uint32_t i;          uint32_t i;
168    
169          data[0] = (int16_t)(coeff[0] * dcscalar);          data[0] = coeff[0] * dcscalar;
170          if (data[0] < -2048) {          if (data[0] < -2048) {
171                  data[0] = -2048;                  data[0] = -2048;
172          } else if (data[0] > 2047) {          } else if (data[0] > 2047) {
# Line 195  Line 182 
182                  } else if (acLevel < 0) {                  } else if (acLevel < 0) {
183                          acLevel = quant_m_2 * -acLevel + quant_add;                          acLevel = quant_m_2 * -acLevel + quant_add;
184                          data[i] = (acLevel <= 2048 ? -acLevel : -2048);                          data[i] = (acLevel <= 2048 ? -acLevel : -2048);
185                  } else                                  /*  if (acLevel > 0) { */                  } else                                  //  if (acLevel > 0) {
186                  {                  {
187                          acLevel = quant_m_2 * acLevel + quant_add;                          acLevel = quant_m_2 * acLevel + quant_add;
188                          data[i] = (acLevel <= 2047 ? acLevel : 2047);                          data[i] = (acLevel <= 2047 ? acLevel : 2047);
# Line 213  Line 200 
200                                  const int16_t * coeff,                                  const int16_t * coeff,
201                                  const uint32_t quant)                                  const uint32_t quant)
202  {  {
203          const uint16_t quant_m_2 = (uint16_t)(quant << 1);          const uint16_t quant_m_2 = quant << 1;
204          const uint16_t quant_add = (uint16_t)(quant & 1 ? quant : quant - 1);          const uint16_t quant_add = (quant & 1 ? quant : quant - 1);
205          uint32_t i;          uint32_t i;
206    
207          for (i = 0; i < 64; i++) {          for (i = 0; i < 64; i++) {
# Line 225  Line 212 
212                  } else if (acLevel < 0) {                  } else if (acLevel < 0) {
213                          acLevel = acLevel * quant_m_2 - quant_add;                          acLevel = acLevel * quant_m_2 - quant_add;
214                          data[i] = (acLevel >= -2048 ? acLevel : -2048);                          data[i] = (acLevel >= -2048 ? acLevel : -2048);
215                  } else                                  /* if (acLevel > 0) */                  } else                                  // if (acLevel > 0)
216                  {                  {
217                          acLevel = acLevel * quant_m_2 + quant_add;                          acLevel = acLevel * quant_m_2 + quant_add;
218                          data[i] = (acLevel <= 2047 ? acLevel : 2047);                          data[i] = (acLevel <= 2047 ? acLevel : 2047);

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