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Diff of /xvidcore/src/quant/quant_h263.c

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revision 1.3, Sat Sep 21 03:07:56 2002 UTC revision 1.6, Sun Dec 15 01:21:12 2002 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 program is an implementation of a part of one or more MPEG-4   *  This file is part of XviD, a free MPEG-4 video encoder/decoder
  *      Video tools as specified in ISO/IEC 14496-2 standard.  Those intending  
  *      to use this software module in hardware or software products are  
  *      advised that its use may infringe existing patents or copyrights, and  
  *      any such use would be at such party's own risk.  The original  
  *      developer of this software module and his/her company, and subsequent  
  *      editors and their companies, will have no liability for use of this  
  *      software or modifications or derivatives thereof.  
7   *   *
8   *      This program is free software; you can redistribute it and/or modify   *  XviD is free software; you can redistribute it and/or modify it
9   *      it under the terms of the GNU General Public License as published by   *  under the terms of the GNU General Public License as published by
10   *      the Free Software Foundation; either version 2 of the License, or   *      the Free Software Foundation; either version 2 of the License, or
11   *      (at your option) any later version.   *      (at your option) any later version.
12   *   *
# Line 24  Line 17 
17   *   *
18   *      You should have received a copy of the GNU General Public License   *      You should have received a copy of the GNU General Public License
19   *      along with this program; if not, write to the Free Software   *      along with this program; if not, write to the Free Software
20   *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.   *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21   *   *
22   *************************************************************************/   *  Under section 8 of the GNU General Public License, the copyright
23     *  holders of XVID explicitly forbid distribution in the following
24  /**************************************************************************   *  countries:
25   *   *
26   *      History:   *    - Japan
27     *    - United States of America
28     *
29     *  Linking XviD statically or dynamically with other modules is making a
30     *  combined work based on XviD.  Thus, the terms and conditions of the
31     *  GNU General Public License cover the whole combination.
32     *
33     *  As a special exception, the copyright holders of XviD give you
34     *  permission to link XviD with independent modules that communicate with
35     *  XviD solely through the VFW1.1 and DShow interfaces, regardless of the
36     *  license terms of these independent modules, and to copy and distribute
37     *  the resulting combined work under terms of your choice, provided that
38     *  every copy of the combined work is accompanied by a complete copy of
39     *  the source code of XviD (the version of XviD used to produce the
40     *  combined work), being distributed under the terms of the GNU General
41     *  Public License plus this exception.  An independent module is a module
42     *  which is not derived from or based on XviD.
43     *
44     *  Note that people who make modified versions of XviD are not obligated
45     *  to grant this special exception for their modified versions; it is
46     *  their choice whether to do so.  The GNU General Public License gives
47     *  permission to release a modified version without this exception; this
48     *  exception also makes it possible to release a modified version which
49     *  carries forward this exception.
50   *   *
51   *  26.12.2001  dequant_inter bug fix   * $Id$
  *      22.12.2001      clamp dequant output to [-2048,2047]  
  *  19.11.2001  quant_inter now returns sum of abs. coefficient values  
  *      02.11.2001      added const to function args <pross@cs.rmit.edu.au>  
  *      28.10.2001      total rewrite (c)2001 peter ross <pross@xvid.org>  
52   *   *
53   *************************************************************************/   *************************************************************************/
54    
# Line 63  Line 75 
75    
76  #define DIV_DIV(a, b) ((a)>0) ? ((a)+((b)>>1))/(b) : ((a)-((b)>>1))/(b)  #define DIV_DIV(a, b) ((a)>0) ? ((a)+((b)>>1))/(b) : ((a)-((b)>>1))/(b)
77    
78  // function pointers  /* function pointers */
79  quanth263_intraFuncPtr quant_intra;  quanth263_intraFuncPtr quant_intra;
80  quanth263_intraFuncPtr dequant_intra;  quanth263_intraFuncPtr dequant_intra;
81    
# Line 83  Line 95 
95                            const uint32_t dcscalar)                            const uint32_t dcscalar)
96  {  {
97          const uint32_t mult = multipliers[quant];          const uint32_t mult = multipliers[quant];
98          const uint16_t quant_m_2 = quant << 1;          const uint16_t quant_m_2 = (uint16_t)(quant << 1);
99          uint32_t i;          uint32_t i;
100    
101          coeff[0] = DIV_DIV(data[0], (int32_t) dcscalar);          coeff[0] = (int16_t)(DIV_DIV(data[0], (int32_t) dcscalar));
102    
103          for (i = 1; i < 64; i++) {          for (i = 1; i < 64; i++) {
104                  int16_t acLevel = data[i];                  int16_t acLevel = data[i];
# Line 97  Line 109 
109                                  coeff[i] = 0;                                  coeff[i] = 0;
110                                  continue;                                  continue;
111                          }                          }
112                          acLevel = (acLevel * mult) >> SCALEBITS;                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);
113                          coeff[i] = -acLevel;                          coeff[i] = -acLevel;
114                  } else {                  } else {
115                          if (acLevel < quant_m_2) {                          if (acLevel < quant_m_2) {
116                                  coeff[i] = 0;                                  coeff[i] = 0;
117                                  continue;                                  continue;
118                          }                          }
119                          acLevel = (acLevel * mult) >> SCALEBITS;                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);
120                          coeff[i] = acLevel;                          coeff[i] = acLevel;
121                  }                  }
122          }          }
# Line 120  Line 132 
132                            const uint32_t quant)                            const uint32_t quant)
133  {  {
134          const uint32_t mult = multipliers[quant];          const uint32_t mult = multipliers[quant];
135          const uint16_t quant_m_2 = quant << 1;          const uint16_t quant_m_2 = (uint16_t)(quant << 1);
136          const uint16_t quant_d_2 = quant >> 1;          const uint16_t quant_d_2 = (uint16_t)(quant >> 1);
137          int sum = 0;          int sum = 0;
138          uint32_t i;          uint32_t i;
139    
# Line 135  Line 147 
147                                  continue;                                  continue;
148                          }                          }
149    
150                          acLevel = (acLevel * mult) >> SCALEBITS;                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);
151                          sum += acLevel;         // sum += |acLevel|                          sum += acLevel;         /* sum += |acLevel| */
152                          coeff[i] = -acLevel;                          coeff[i] = -acLevel;
153                  } else {                  } else {
154                          acLevel -= quant_d_2;                          acLevel -= quant_d_2;
# Line 144  Line 156 
156                                  coeff[i] = 0;                                  coeff[i] = 0;
157                                  continue;                                  continue;
158                          }                          }
159                          acLevel = (acLevel * mult) >> SCALEBITS;                          acLevel = (int16_t)(((uint32_t)acLevel * mult) >> SCALEBITS);
160                          sum += acLevel;                          sum += acLevel;
161                          coeff[i] = acLevel;                          coeff[i] = acLevel;
162                  }                  }
# Line 167  Line 179 
179          const int32_t quant_add = (quant & 1 ? quant : quant - 1);          const int32_t quant_add = (quant & 1 ? quant : quant - 1);
180          uint32_t i;          uint32_t i;
181    
182          data[0] = coeff[0] * dcscalar;          data[0] = (int16_t)(coeff[0] * dcscalar);
183          if (data[0] < -2048) {          if (data[0] < -2048) {
184                  data[0] = -2048;                  data[0] = -2048;
185          } else if (data[0] > 2047) {          } else if (data[0] > 2047) {
# Line 183  Line 195 
195                  } else if (acLevel < 0) {                  } else if (acLevel < 0) {
196                          acLevel = quant_m_2 * -acLevel + quant_add;                          acLevel = quant_m_2 * -acLevel + quant_add;
197                          data[i] = (acLevel <= 2048 ? -acLevel : -2048);                          data[i] = (acLevel <= 2048 ? -acLevel : -2048);
198                  } else                                  //  if (acLevel > 0) {                  } else                                  /*  if (acLevel > 0) { */
199                  {                  {
200                          acLevel = quant_m_2 * acLevel + quant_add;                          acLevel = quant_m_2 * acLevel + quant_add;
201                          data[i] = (acLevel <= 2047 ? acLevel : 2047);                          data[i] = (acLevel <= 2047 ? acLevel : 2047);
# Line 201  Line 213 
213                                  const int16_t * coeff,                                  const int16_t * coeff,
214                                  const uint32_t quant)                                  const uint32_t quant)
215  {  {
216          const uint16_t quant_m_2 = quant << 1;          const uint16_t quant_m_2 = (uint16_t)(quant << 1);
217          const uint16_t quant_add = (quant & 1 ? quant : quant - 1);          const uint16_t quant_add = (uint16_t)(quant & 1 ? quant : quant - 1);
218          uint32_t i;          uint32_t i;
219    
220          for (i = 0; i < 64; i++) {          for (i = 0; i < 64; i++) {
# Line 213  Line 225 
225                  } else if (acLevel < 0) {                  } else if (acLevel < 0) {
226                          acLevel = acLevel * quant_m_2 - quant_add;                          acLevel = acLevel * quant_m_2 - quant_add;
227                          data[i] = (acLevel >= -2048 ? acLevel : -2048);                          data[i] = (acLevel >= -2048 ? acLevel : -2048);
228                  } else                                  // if (acLevel > 0)                  } else                                  /* if (acLevel > 0) */
229                  {                  {
230                          acLevel = acLevel * quant_m_2 + quant_add;                          acLevel = acLevel * quant_m_2 + quant_add;
231                          data[i] = (acLevel <= 2047 ? acLevel : 2047);                          data[i] = (acLevel <= 2047 ? acLevel : 2047);

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