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revision 1.1, Fri Mar 8 02:44:39 2002 UTC revision 1.6.2.1, Mon Jun 9 01:19:37 2003 UTC
# Line 52  Line 52 
52  /* this code assumes >> to be a two's-complement arithmetic */  /* this code assumes >> to be a two's-complement arithmetic */
53  /* right shift: (-2)>>1 == -1 , (-3)>>1 == -2               */  /* right shift: (-2)>>1 == -1 , (-3)>>1 == -2               */
54    
 //#include <windows.h>  
55  #include "idct.h"  #include "idct.h"
56    
57  #define W1 2841 /* 2048*sqrt(2)*cos(1*pi/16) */  #define W1 2841 /* 2048*sqrt(2)*cos(1*pi/16) */
# Line 62  Line 61 
61  #define W6 1108 /* 2048*sqrt(2)*cos(6*pi/16) */  #define W6 1108 /* 2048*sqrt(2)*cos(6*pi/16) */
62  #define W7 565  /* 2048*sqrt(2)*cos(7*pi/16) */  #define W7 565  /* 2048*sqrt(2)*cos(7*pi/16) */
63    
   
 /* global declarations */  
 //void init_idct_int32 (void);  
 //void idct_int32 (short *block);  
   
64  /* private data */  /* private data */
65  static short iclip[1024]; /* clipping table */  static short iclip[1024]; /* clipping table */
66  static short *iclp;  static short *iclp;
67    
68  /* private prototypes */  /* private prototypes */
 //static void idctrow _ANSI_ARGS_((short *blk));  
 //static void idctcol _ANSI_ARGS_((short *blk));  
69    
70  /* row (horizontal) IDCT  /* row (horizontal) IDCT
71   *   *
# Line 85  Line 77 
77   *        c[1..7] = 128*sqrt(2)   *        c[1..7] = 128*sqrt(2)
78   */   */
79    
80  /*  #if 0
81  static void idctrow(blk)  static void idctrow(blk)
82  short *blk;  short *blk;
83  {  {
84    int X0, X1, X2, X3, X4, X5, X6, X7, X8;    int X0, X1, X2, X3, X4, X5, X6, X7, X8;
85    
86    // shortcut    /* shortcut  */
87    if (!((X1 = blk[4]<<11) | (X2 = blk[6]) | (X3 = blk[2]) |    if (!((X1 = blk[4]<<11) | (X2 = blk[6]) | (X3 = blk[2]) |
88          (X4 = blk[1]) | (X5 = blk[7]) | (X6 = blk[5]) | (X7 = blk[3])))          (X4 = blk[1]) | (X5 = blk[7]) | (X6 = blk[5]) | (X7 = blk[3])))
89    {    {
# Line 99  Line 91 
91      return;      return;
92    }    }
93    
94    X0 = (blk[0]<<11) + 128; // for proper rounding in the fourth stage    X0 = (blk[0]<<11) + 128; /* for proper rounding in the fourth stage  */
95    
96    // first stage    /* first stage  */
97    X8 = W7*(X4+X5);    X8 = W7*(X4+X5);
98    X4 = X8 + (W1-W7)*X4;    X4 = X8 + (W1-W7)*X4;
99    X5 = X8 - (W1+W7)*X5;    X5 = X8 - (W1+W7)*X5;
# Line 109  Line 101 
101    X6 = X8 - (W3-W5)*X6;    X6 = X8 - (W3-W5)*X6;
102    X7 = X8 - (W3+W5)*X7;    X7 = X8 - (W3+W5)*X7;
103    
104    // second stage    /* second stage  */
105    X8 = X0 + X1;    X8 = X0 + X1;
106    X0 -= X1;    X0 -= X1;
107    X1 = W6*(X3+X2);    X1 = W6*(X3+X2);
# Line 120  Line 112 
112    X6 = X5 + X7;    X6 = X5 + X7;
113    X5 -= X7;    X5 -= X7;
114    
115    // third stage    /* third stage  */
116    X7 = X8 + X3;    X7 = X8 + X3;
117    X8 -= X3;    X8 -= X3;
118    X3 = X0 + X2;    X3 = X0 + X2;
# Line 128  Line 120 
120    X2 = (181*(X4+X5)+128)>>8;    X2 = (181*(X4+X5)+128)>>8;
121    X4 = (181*(X4-X5)+128)>>8;    X4 = (181*(X4-X5)+128)>>8;
122    
123    // fourth stage    /* fourth stage  */
124    blk[0] = (X7+X1)>>8;    blk[0] = (X7+X1)>>8;
125    blk[1] = (X3+X2)>>8;    blk[1] = (X3+X2)>>8;
126    blk[2] = (X0+X4)>>8;    blk[2] = (X0+X4)>>8;
# Line 137  Line 129 
129    blk[5] = (X0-X4)>>8;    blk[5] = (X0-X4)>>8;
130    blk[6] = (X3-X2)>>8;    blk[6] = (X3-X2)>>8;
131    blk[7] = (X7-X1)>>8;    blk[7] = (X7-X1)>>8;
132  }*/  }
133    #endif
134    
135  /* column (vertical) IDCT  /* column (vertical) IDCT
136   *   *
# Line 148  Line 141 
141   * where: c[0]    = 1/1024   * where: c[0]    = 1/1024
142   *        c[1..7] = (1/1024)*sqrt(2)   *        c[1..7] = (1/1024)*sqrt(2)
143   */   */
144  /*  
145    #if 0
146  static void idctcol(blk)  static void idctcol(blk)
147  short *blk;  short *blk;
148  {  {
149    int X0, X1, X2, X3, X4, X5, X6, X7, X8;    int X0, X1, X2, X3, X4, X5, X6, X7, X8;
150    
151    // shortcut    /* shortcut  */
152    if (!((X1 = (blk[8*4]<<8)) | (X2 = blk[8*6]) | (X3 = blk[8*2]) |    if (!((X1 = (blk[8*4]<<8)) | (X2 = blk[8*6]) | (X3 = blk[8*2]) |
153          (X4 = blk[8*1]) | (X5 = blk[8*7]) | (X6 = blk[8*5]) | (X7 = blk[8*3])))          (X4 = blk[8*1]) | (X5 = blk[8*7]) | (X6 = blk[8*5]) | (X7 = blk[8*3])))
154    {    {
# Line 165  Line 159 
159    
160    X0 = (blk[8*0]<<8) + 8192;    X0 = (blk[8*0]<<8) + 8192;
161    
162    // first stage    /* first stage  */
163    X8 = W7*(X4+X5) + 4;    X8 = W7*(X4+X5) + 4;
164    X4 = (X8+(W1-W7)*X4)>>3;    X4 = (X8+(W1-W7)*X4)>>3;
165    X5 = (X8-(W1+W7)*X5)>>3;    X5 = (X8-(W1+W7)*X5)>>3;
# Line 173  Line 167 
167    X6 = (X8-(W3-W5)*X6)>>3;    X6 = (X8-(W3-W5)*X6)>>3;
168    X7 = (X8-(W3+W5)*X7)>>3;    X7 = (X8-(W3+W5)*X7)>>3;
169    
170    // second stage    /* second stage */
171    X8 = X0 + X1;    X8 = X0 + X1;
172    X0 -= X1;    X0 -= X1;
173    X1 = W6*(X3+X2) + 4;    X1 = W6*(X3+X2) + 4;
# Line 184  Line 178 
178    X6 = X5 + X7;    X6 = X5 + X7;
179    X5 -= X7;    X5 -= X7;
180    
181    // third stage    /* third stage  */
182    X7 = X8 + X3;    X7 = X8 + X3;
183    X8 -= X3;    X8 -= X3;
184    X3 = X0 + X2;    X3 = X0 + X2;
# Line 192  Line 186 
186    X2 = (181*(X4+X5)+128)>>8;    X2 = (181*(X4+X5)+128)>>8;
187    X4 = (181*(X4-X5)+128)>>8;    X4 = (181*(X4-X5)+128)>>8;
188    
189    // fourth stage    /* fourth stage */
190    blk[8*0] = iclp[(X7+X1)>>14];    blk[8*0] = iclp[(X7+X1)>>14];
191    blk[8*1] = iclp[(X3+X2)>>14];    blk[8*1] = iclp[(X3+X2)>>14];
192    blk[8*2] = iclp[(X0+X4)>>14];    blk[8*2] = iclp[(X0+X4)>>14];
# Line 201  Line 195 
195    blk[8*5] = iclp[(X0-X4)>>14];    blk[8*5] = iclp[(X0-X4)>>14];
196    blk[8*6] = iclp[(X3-X2)>>14];    blk[8*6] = iclp[(X3-X2)>>14];
197    blk[8*7] = iclp[(X7-X1)>>14];    blk[8*7] = iclp[(X7-X1)>>14];
198  }*/  }
199    #endif
200    
201  // function pointer  /* function pointer */
202  idctFuncPtr idct;  idctFuncPtr idct;
203    
204  /* two dimensional inverse discrete cosine transform */  /* two dimensional inverse discrete cosine transform */
205  //void j_rev_dct(block)  void
206  //short *block;  idct_int32(short *const block)
 void idct_int32(short * const block)  
207  {  {
208    
209    // idct_int32_init() must be called before the first call to this function!          /*
210             * idct_int32_init() must be called before the first call to this
211             * function!
212             */
213    
214    
215    /*int i;  #if 0
216            int i;
217    long i;    long i;
218    
219    for (i=0; i<8; i++)    for (i=0; i<8; i++)
220      idctrow(block+8*i);      idctrow(block+8*i);
221    
222    for (i=0; i<8; i++)    for (i=0; i<8; i++)
223      idctcol(block+i);*/                  idctcol(block+i);
224    #endif
225    
226    static short *blk;    static short *blk;
227    static long i;    static long i;
228    static long X0, X1, X2, X3, X4, X5, X6, X7, X8;    static long X0, X1, X2, X3, X4, X5, X6, X7, X8;
229    
230    
231    for (i=0; i<8; i++)   // idct rows          for (i = 0; i < 8; i++)         /* idct rows */
232    {    {
233          blk = block+(i<<3);          blk = block+(i<<3);
234          if (!((X1 = blk[4]<<11) | (X2 = blk[6]) | (X3 = blk[2]) |                  if (!
235          (X4 = blk[1]) | (X5 = blk[7]) | (X6 = blk[5]) | (X7 = blk[3])))                          ((X1 = blk[4] << 11) | (X2 = blk[6]) | (X3 = blk[2]) | (X4 =
236          {                                                                                                                                          blk[1]) |
237                  blk[0]=blk[1]=blk[2]=blk[3]=blk[4]=blk[5]=blk[6]=blk[7]=blk[0]<<3;                           (X5 = blk[7]) | (X6 = blk[5]) | (X7 = blk[3]))) {
238                            blk[0] = blk[1] = blk[2] = blk[3] = blk[4] = blk[5] = blk[6] =
239                                    blk[7] = blk[0] << 3;
240                  continue;                  continue;
241          }          }
242    
243          X0 = (blk[0]<<11) + 128; // for proper rounding in the fourth stage                  X0 = (blk[0] << 11) + 128;      /* for proper rounding in the fourth stage  */
244    
245          // first stage                  /* first stage  */
246          X8 = W7*(X4+X5);          X8 = W7*(X4+X5);
247          X4 = X8 + (W1-W7)*X4;          X4 = X8 + (W1-W7)*X4;
248          X5 = X8 - (W1+W7)*X5;          X5 = X8 - (W1+W7)*X5;
# Line 248  Line 250 
250          X6 = X8 - (W3-W5)*X6;          X6 = X8 - (W3-W5)*X6;
251          X7 = X8 - (W3+W5)*X7;          X7 = X8 - (W3+W5)*X7;
252    
253          // second stage                  /* second stage  */
254          X8 = X0 + X1;          X8 = X0 + X1;
255          X0 -= X1;          X0 -= X1;
256          X1 = W6*(X3+X2);          X1 = W6*(X3+X2);
# Line 259  Line 261 
261          X6 = X5 + X7;          X6 = X5 + X7;
262          X5 -= X7;          X5 -= X7;
263    
264          // third stage                  /* third stage  */
265          X7 = X8 + X3;          X7 = X8 + X3;
266          X8 -= X3;          X8 -= X3;
267          X3 = X0 + X2;          X3 = X0 + X2;
# Line 267  Line 269 
269          X2 = (181*(X4+X5)+128)>>8;          X2 = (181*(X4+X5)+128)>>8;
270          X4 = (181*(X4-X5)+128)>>8;          X4 = (181*(X4-X5)+128)>>8;
271    
272          // fourth stage                  /* fourth stage  */
273    
274          blk[0] = (short)((X7+X1)>>8);          blk[0] = (short)((X7+X1)>>8);
275          blk[1] = (short)((X3+X2)>>8);          blk[1] = (short)((X3+X2)>>8);
# Line 278  Line 280 
280          blk[6] = (short)((X3-X2)>>8);          blk[6] = (short)((X3-X2)>>8);
281          blk[7] = (short)((X7-X1)>>8);          blk[7] = (short)((X7-X1)>>8);
282    
283    } // end for ( i = 0; i < 8; ++i ) IDCT-rows          }                                                       /* end for ( i = 0; i < 8; ++i ) IDCT-rows */
284    
285    
286    
287    for (i=0; i<8; i++)   // idct columns          for (i = 0; i < 8; i++)         /* idct columns */
288    {    {
289          blk = block + i;          blk = block + i;
290      // shortcut                  /* shortcut  */
291          if (!((X1 = (blk[8*4]<<8)) | (X2 = blk[8*6]) | (X3 = blk[8*2]) |                  if (!
292          (X4 = blk[8*1]) | (X5 = blk[8*7]) | (X6 = blk[8*5]) | (X7 = blk[8*3])))                          ((X1 = (blk[8 * 4] << 8)) | (X2 = blk[8 * 6]) | (X3 =
293          {                                                                                                                           blk[8 *
294                                                                                                                                     2]) | (X4 =
295                                                                                                                                                    blk[8 *
296                                                                                                                                                            1])
297                             | (X5 = blk[8 * 7]) | (X6 = blk[8 * 5]) | (X7 = blk[8 * 3]))) {
298                  blk[8*0]=blk[8*1]=blk[8*2]=blk[8*3]=blk[8*4]=                  blk[8*0]=blk[8*1]=blk[8*2]=blk[8*3]=blk[8*4]=
299                          blk[8*5]=blk[8*6]=blk[8*7]=iclp[(blk[8*0]+32)>>6];                                  blk[8 * 5] = blk[8 * 6] = blk[8 * 7] =
300                                    iclp[(blk[8 * 0] + 32) >> 6];
301                  continue;                  continue;
302          }          }
303    
304          X0 = (blk[8*0]<<8) + 8192;          X0 = (blk[8*0]<<8) + 8192;
305    
306          // first stage                  /* first stage  */
307          X8 = W7*(X4+X5) + 4;          X8 = W7*(X4+X5) + 4;
308          X4 = (X8+(W1-W7)*X4)>>3;          X4 = (X8+(W1-W7)*X4)>>3;
309          X5 = (X8-(W1+W7)*X5)>>3;          X5 = (X8-(W1+W7)*X5)>>3;
# Line 304  Line 311 
311          X6 = (X8-(W3-W5)*X6)>>3;          X6 = (X8-(W3-W5)*X6)>>3;
312          X7 = (X8-(W3+W5)*X7)>>3;          X7 = (X8-(W3+W5)*X7)>>3;
313    
314          // second stage                  /* second stage  */
315          X8 = X0 + X1;          X8 = X0 + X1;
316          X0 -= X1;          X0 -= X1;
317          X1 = W6*(X3+X2) + 4;          X1 = W6*(X3+X2) + 4;
# Line 315  Line 322 
322          X6 = X5 + X7;          X6 = X5 + X7;
323          X5 -= X7;          X5 -= X7;
324    
325          // third stage                  /* third stage  */
326          X7 = X8 + X3;          X7 = X8 + X3;
327          X8 -= X3;          X8 -= X3;
328          X3 = X0 + X2;          X3 = X0 + X2;
# Line 323  Line 330 
330          X2 = (181*(X4+X5)+128)>>8;          X2 = (181*(X4+X5)+128)>>8;
331          X4 = (181*(X4-X5)+128)>>8;          X4 = (181*(X4-X5)+128)>>8;
332    
333          // fourth stage                  /* fourth stage  */
334          blk[8*0] = iclp[(X7+X1)>>14];          blk[8*0] = iclp[(X7+X1)>>14];
335          blk[8*1] = iclp[(X3+X2)>>14];          blk[8*1] = iclp[(X3+X2)>>14];
336          blk[8*2] = iclp[(X0+X4)>>14];          blk[8*2] = iclp[(X0+X4)>>14];
# Line 334  Line 341 
341          blk[8*7] = iclp[(X7-X1)>>14];          blk[8*7] = iclp[(X7-X1)>>14];
342    }    }
343    
344  } // end function idct_int32(block)  }                                                               /* end function idct_int32(block) */
345    
346    
347  //void  void
348  //idct_int32_init()  idct_int32_init()
 void idct_int32_init()  
349  {  {
350    int i;    int i;
351    
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