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revision 1.7, Sat Feb 15 15:22:19 2003 UTC revision 1.7.2.3, Thu Oct 9 18:50:22 2003 UTC
# Line 1  Line 1 
1  /**************************************************************************  /*****************************************************************************
2   *   *
3   *      XVID MPEG-4 VIDEO CODEC   *      XVID MPEG-4 VIDEO CODEC
4   *      quantization/dequantization   *  - MPEG4 Quantization H263 implementation -
5   *   *
6   *      This program is an implementation of a part of one or more MPEG-4   *  Copyright(C) 2001-2003 Peter Ross <pross@xvid.org>
  *      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   *      This program is free software; you can redistribute it and/or modify
9   *      it 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
# 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   *************************************************************************/   * $Id$
   
 /**************************************************************************  
  *  
  *      History:  
23   *   *
24   *  26.12.2001  dequant_inter bug fix   ****************************************************************************/
  *      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 <pross@cs.rmit.edu.au>  
  *  
  *************************************************************************/  
25    
26  #include "../global.h"  #include "../global.h"
27  #include "quant_h263.h"  #include "quant.h"
28    
29  /*      mutliply+shift division table  /*****************************************************************************
30  */   * Global function pointers
31     ****************************************************************************/
32    
33    /* Quant */
34    quant_intraFuncPtr quant_h263_intra;
35    quant_interFuncPtr quant_h263_inter;
36    
37    /* DeQuant */
38    quant_intraFuncPtr dequant_h263_intra;
39    quant_interFuncPtr dequant_h263_inter;
40    
41    /*****************************************************************************
42     * Local data
43     ****************************************************************************/
44    
45    /* divide-by-multiply table
46     * a 16 bit shiting is enough in this case */
47    
48  #define SCALEBITS       16  #define SCALEBITS       16
49  #define FIX(X)          ((1L << SCALEBITS) / (X) + 1)  #define FIX(X)          ((1L << SCALEBITS) / (X) + 1)
50    
51  static const uint32_t multipliers[32] = {  static const uint32_t multipliers[32] =
52    {
53          0, FIX(2), FIX(4), FIX(6),          0, FIX(2), FIX(4), FIX(6),
54          FIX(8), FIX(10), FIX(12), FIX(14),          FIX(8), FIX(10), FIX(12), FIX(14),
55          FIX(16), FIX(18), FIX(20), FIX(22),          FIX(16), FIX(18), FIX(20), FIX(22),
# Line 60  Line 60 
60          FIX(56), FIX(58), FIX(60), FIX(62)          FIX(56), FIX(58), FIX(60), FIX(62)
61  };  };
62    
63    /*****************************************************************************
64     * Function definitions
65  // function pointers   ****************************************************************************/
 quanth263_intraFuncPtr quant_intra;  
 quanth263_intraFuncPtr dequant_intra;  
   
 quanth263_interFuncPtr quant_inter;  
 dequanth263_interFuncPtr dequant_inter;  
   
   
66    
67  /*      quantize intra-block  /*      quantize intra-block
68  */  */
69    
70    uint32_t
71  void  quant_h263_intra_c(int16_t * coeff,
 quant_intra_c(int16_t * coeff,  
72                            const int16_t * data,                            const int16_t * data,
73                            const uint32_t quant,                            const uint32_t quant,
74                            const uint32_t dcscalar)                            const uint32_t dcscalar)
75  {  {
76          const uint32_t mult = multipliers[quant];          const uint32_t mult = multipliers[quant];
77          const uint16_t quant_m_2 = quant << 1;          const uint16_t quant_m_2 = quant << 1;
78          uint32_t i;          int i;
79    
80          coeff[0] = DIV_DIV(data[0], (int32_t) dcscalar);          coeff[0] = DIV_DIV(data[0], (int32_t) dcscalar);
81    
# Line 107  Line 99 
99                          coeff[i] = acLevel;                          coeff[i] = acLevel;
100                  }                  }
101          }          }
102    
103            return(0);
104  }  }
105    
106    
# Line 114  Line 108 
108  */  */
109    
110  uint32_t  uint32_t
111  quant_inter_c(int16_t * coeff,  quant_h263_inter_c(int16_t * coeff,
112                            const int16_t * data,                            const int16_t * data,
113                            const uint32_t quant)                            const uint32_t quant)
114  {  {
115          const uint32_t mult = multipliers[quant];          const uint32_t mult = multipliers[quant];
116          const uint16_t quant_m_2 = quant << 1;          const uint16_t quant_m_2 = quant << 1;
117          const uint16_t quant_d_2 = quant >> 1;          const uint16_t quant_d_2 = quant >> 1;
118          int sum = 0;          uint32_t sum = 0;
119          uint32_t i;          uint32_t i;
120    
121          for (i = 0; i < 64; i++) {          for (i = 0; i < 64; i++) {
# Line 135  Line 129 
129                          }                          }
130    
131                          acLevel = (acLevel * mult) >> SCALEBITS;                          acLevel = (acLevel * mult) >> SCALEBITS;
132                          sum += acLevel;         // sum += |acLevel|                          sum += acLevel;         /* sum += |acLevel| */
133                          coeff[i] = -acLevel;                          coeff[i] = -acLevel;
134                  } else {                  } else {
135                          acLevel -= quant_d_2;                          acLevel -= quant_d_2;
# Line 149  Line 143 
143                  }                  }
144          }          }
145    
146          return sum;          return(sum);
147  }  }
148    
149    
150  /*      dequantize intra-block & clamp to [-2048,2047]  /*      dequantize intra-block & clamp to [-2048,2047]
151  */  */
152    
153  void  uint32_t
154  dequant_intra_c(int16_t * data,  dequant_h263_intra_c(int16_t * data,
155                                  const int16_t * coeff,                                  const int16_t * coeff,
156                                  const uint32_t quant,                                  const uint32_t quant,
157                                  const uint32_t dcscalar)                                  const uint32_t dcscalar)
158  {  {
159          const int32_t quant_m_2 = quant << 1;          const int32_t quant_m_2 = quant << 1;
160          const int32_t quant_add = (quant & 1 ? quant : quant - 1);          const int32_t quant_add = (quant & 1 ? quant : quant - 1);
161          uint32_t i;          int i;
162    
163          data[0] = coeff[0] * dcscalar;          data[0] = coeff[0] * dcscalar;
164          if (data[0] < -2048) {          if (data[0] < -2048) {
# Line 173  Line 167 
167                  data[0] = 2047;                  data[0] = 2047;
168          }          }
169    
   
170          for (i = 1; i < 64; i++) {          for (i = 1; i < 64; i++) {
171                  int32_t acLevel = coeff[i];                  int32_t acLevel = coeff[i];
172    
# Line 182  Line 175 
175                  } else if (acLevel < 0) {                  } else if (acLevel < 0) {
176                          acLevel = quant_m_2 * -acLevel + quant_add;                          acLevel = quant_m_2 * -acLevel + quant_add;
177                          data[i] = (acLevel <= 2048 ? -acLevel : -2048);                          data[i] = (acLevel <= 2048 ? -acLevel : -2048);
178                  } else                                  //  if (acLevel > 0) {                  } else {
                 {  
179                          acLevel = quant_m_2 * acLevel + quant_add;                          acLevel = quant_m_2 * acLevel + quant_add;
180                          data[i] = (acLevel <= 2047 ? acLevel : 2047);                          data[i] = (acLevel <= 2047 ? acLevel : 2047);
181                  }                  }
182          }          }
183    
184            return(0);
185  }  }
186    
187    
# Line 195  Line 189 
189  /* dequantize inter-block & clamp to [-2048,2047]  /* dequantize inter-block & clamp to [-2048,2047]
190  */  */
191    
192  void  uint32_t
193  dequant_inter_c(int16_t * data,  dequant_h263_inter_c(int16_t * data,
194                                  const int16_t * coeff,                                  const int16_t * coeff,
195                                  const uint32_t quant)                                  const uint32_t quant)
196  {  {
197          const uint16_t quant_m_2 = quant << 1;          const uint16_t quant_m_2 = quant << 1;
198          const uint16_t quant_add = (quant & 1 ? quant : quant - 1);          const uint16_t quant_add = (quant & 1 ? quant : quant - 1);
199          uint32_t i;          int i;
200    
201          for (i = 0; i < 64; i++) {          for (i = 0; i < 64; i++) {
202                  int16_t acLevel = coeff[i];                  int16_t acLevel = coeff[i];
# Line 212  Line 206 
206                  } else if (acLevel < 0) {                  } else if (acLevel < 0) {
207                          acLevel = acLevel * quant_m_2 - quant_add;                          acLevel = acLevel * quant_m_2 - quant_add;
208                          data[i] = (acLevel >= -2048 ? acLevel : -2048);                          data[i] = (acLevel >= -2048 ? acLevel : -2048);
209                  } else                                  // if (acLevel > 0)                  } else {
                 {  
210                          acLevel = acLevel * quant_m_2 + quant_add;                          acLevel = acLevel * quant_m_2 + quant_add;
211                          data[i] = (acLevel <= 2047 ? acLevel : 2047);                          data[i] = (acLevel <= 2047 ? acLevel : 2047);
212                  }                  }
213          }          }
214    
215            return(0);
216  }  }
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