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-rw-r--r--gst-libs/gst/idct/fastintidct.c156
1 files changed, 80 insertions, 76 deletions
diff --git a/gst-libs/gst/idct/fastintidct.c b/gst-libs/gst/idct/fastintidct.c
index 27426672..9bb1436d 100644
--- a/gst-libs/gst/idct/fastintidct.c
+++ b/gst-libs/gst/idct/fastintidct.c
@@ -45,17 +45,17 @@
/* this code assumes >> to be a two's-complement arithmetic */
/* right shift: (-2)>>1 == -1 , (-3)>>1 == -2 */
-#define W1 2841 /* 2048*sqrt(2)*cos(1*pi/16) */
-#define W2 2676 /* 2048*sqrt(2)*cos(2*pi/16) */
-#define W3 2408 /* 2048*sqrt(2)*cos(3*pi/16) */
-#define W5 1609 /* 2048*sqrt(2)*cos(5*pi/16) */
-#define W6 1108 /* 2048*sqrt(2)*cos(6*pi/16) */
-#define W7 565 /* 2048*sqrt(2)*cos(7*pi/16) */
+#define W1 2841 /* 2048*sqrt(2)*cos(1*pi/16) */
+#define W2 2676 /* 2048*sqrt(2)*cos(2*pi/16) */
+#define W3 2408 /* 2048*sqrt(2)*cos(3*pi/16) */
+#define W5 1609 /* 2048*sqrt(2)*cos(5*pi/16) */
+#define W6 1108 /* 2048*sqrt(2)*cos(6*pi/16) */
+#define W7 565 /* 2048*sqrt(2)*cos(7*pi/16) */
#include "dct.h"
/* private data */
-static short iclip[1024]; /* clipping table */
+static short iclip[1024]; /* clipping table */
static short *iclp;
/* private prototypes */
@@ -72,57 +72,58 @@ static void idctcol (short *blk);
* c[1..7] = 128*sqrt(2)
*/
-static void idctrow(blk)
-short *blk;
+static void
+idctrow (blk)
+ short *blk;
{
int x0, x1, x2, x3, x4, x5, x6, x7, x8;
/* shortcut */
- if (!((x1 = blk[4]<<11) | (x2 = blk[6]) | (x3 = blk[2]) |
- (x4 = blk[1]) | (x5 = blk[7]) | (x6 = blk[5]) | (x7 = blk[3])))
- {
- blk[0]=blk[1]=blk[2]=blk[3]=blk[4]=blk[5]=blk[6]=blk[7]=blk[0]<<3;
+ if (!((x1 = blk[4] << 11) | (x2 = blk[6]) | (x3 = blk[2]) |
+ (x4 = blk[1]) | (x5 = blk[7]) | (x6 = blk[5]) | (x7 = blk[3]))) {
+ blk[0] = blk[1] = blk[2] = blk[3] = blk[4] = blk[5] = blk[6] = blk[7] =
+ blk[0] << 3;
return;
}
- x0 = (blk[0]<<11) + 128; /* for proper rounding in the fourth stage */
+ x0 = (blk[0] << 11) + 128; /* for proper rounding in the fourth stage */
/* first stage */
- x8 = W7*(x4+x5);
- x4 = x8 + (W1-W7)*x4;
- x5 = x8 - (W1+W7)*x5;
- x8 = W3*(x6+x7);
- x6 = x8 - (W3-W5)*x6;
- x7 = x8 - (W3+W5)*x7;
-
+ x8 = W7 * (x4 + x5);
+ x4 = x8 + (W1 - W7) * x4;
+ x5 = x8 - (W1 + W7) * x5;
+ x8 = W3 * (x6 + x7);
+ x6 = x8 - (W3 - W5) * x6;
+ x7 = x8 - (W3 + W5) * x7;
+
/* second stage */
x8 = x0 + x1;
x0 -= x1;
- x1 = W6*(x3+x2);
- x2 = x1 - (W2+W6)*x2;
- x3 = x1 + (W2-W6)*x3;
+ x1 = W6 * (x3 + x2);
+ x2 = x1 - (W2 + W6) * x2;
+ x3 = x1 + (W2 - W6) * x3;
x1 = x4 + x6;
x4 -= x6;
x6 = x5 + x7;
x5 -= x7;
-
+
/* third stage */
x7 = x8 + x3;
x8 -= x3;
x3 = x0 + x2;
x0 -= x2;
- x2 = (181*(x4+x5)+128)>>8;
- x4 = (181*(x4-x5)+128)>>8;
-
+ x2 = (181 * (x4 + x5) + 128) >> 8;
+ x4 = (181 * (x4 - x5) + 128) >> 8;
+
/* fourth stage */
- blk[0] = (x7+x1)>>8;
- blk[1] = (x3+x2)>>8;
- blk[2] = (x0+x4)>>8;
- blk[3] = (x8+x6)>>8;
- blk[4] = (x8-x6)>>8;
- blk[5] = (x0-x4)>>8;
- blk[6] = (x3-x2)>>8;
- blk[7] = (x7-x1)>>8;
+ blk[0] = (x7 + x1) >> 8;
+ blk[1] = (x3 + x2) >> 8;
+ blk[2] = (x0 + x4) >> 8;
+ blk[3] = (x8 + x6) >> 8;
+ blk[4] = (x8 - x6) >> 8;
+ blk[5] = (x0 - x4) >> 8;
+ blk[6] = (x3 - x2) >> 8;
+ blk[7] = (x7 - x1) >> 8;
}
/* column (vertical) IDCT
@@ -134,78 +135,81 @@ short *blk;
* where: c[0] = 1/1024
* c[1..7] = (1/1024)*sqrt(2)
*/
-static void idctcol(blk)
-short *blk;
+static void
+idctcol (blk)
+ short *blk;
{
int x0, x1, x2, x3, x4, x5, x6, x7, x8;
/* shortcut */
- if (!((x1 = (blk[8*4]<<8)) | (x2 = blk[8*6]) | (x3 = blk[8*2]) |
- (x4 = blk[8*1]) | (x5 = blk[8*7]) | (x6 = blk[8*5]) | (x7 = blk[8*3])))
- {
- blk[8*0]=blk[8*1]=blk[8*2]=blk[8*3]=blk[8*4]=blk[8*5]=blk[8*6]=blk[8*7]=
- iclp[(blk[8*0]+32)>>6];
+ if (!((x1 = (blk[8 * 4] << 8)) | (x2 = blk[8 * 6]) | (x3 = blk[8 * 2]) |
+ (x4 = blk[8 * 1]) | (x5 = blk[8 * 7]) | (x6 = blk[8 * 5]) | (x7 =
+ blk[8 * 3]))) {
+ blk[8 * 0] = blk[8 * 1] = blk[8 * 2] = blk[8 * 3] = blk[8 * 4] =
+ blk[8 * 5] = blk[8 * 6] = blk[8 * 7] = iclp[(blk[8 * 0] + 32) >> 6];
return;
}
- x0 = (blk[8*0]<<8) + 8192;
+ x0 = (blk[8 * 0] << 8) + 8192;
/* first stage */
- x8 = W7*(x4+x5) + 4;
- x4 = (x8+(W1-W7)*x4)>>3;
- x5 = (x8-(W1+W7)*x5)>>3;
- x8 = W3*(x6+x7) + 4;
- x6 = (x8-(W3-W5)*x6)>>3;
- x7 = (x8-(W3+W5)*x7)>>3;
-
+ x8 = W7 * (x4 + x5) + 4;
+ x4 = (x8 + (W1 - W7) * x4) >> 3;
+ x5 = (x8 - (W1 + W7) * x5) >> 3;
+ x8 = W3 * (x6 + x7) + 4;
+ x6 = (x8 - (W3 - W5) * x6) >> 3;
+ x7 = (x8 - (W3 + W5) * x7) >> 3;
+
/* second stage */
x8 = x0 + x1;
x0 -= x1;
- x1 = W6*(x3+x2) + 4;
- x2 = (x1-(W2+W6)*x2)>>3;
- x3 = (x1+(W2-W6)*x3)>>3;
+ x1 = W6 * (x3 + x2) + 4;
+ x2 = (x1 - (W2 + W6) * x2) >> 3;
+ x3 = (x1 + (W2 - W6) * x3) >> 3;
x1 = x4 + x6;
x4 -= x6;
x6 = x5 + x7;
x5 -= x7;
-
+
/* third stage */
x7 = x8 + x3;
x8 -= x3;
x3 = x0 + x2;
x0 -= x2;
- x2 = (181*(x4+x5)+128)>>8;
- x4 = (181*(x4-x5)+128)>>8;
-
+ x2 = (181 * (x4 + x5) + 128) >> 8;
+ x4 = (181 * (x4 - x5) + 128) >> 8;
+
/* fourth stage */
- blk[8*0] = iclp[(x7+x1)>>14];
- blk[8*1] = iclp[(x3+x2)>>14];
- blk[8*2] = iclp[(x0+x4)>>14];
- blk[8*3] = iclp[(x8+x6)>>14];
- blk[8*4] = iclp[(x8-x6)>>14];
- blk[8*5] = iclp[(x0-x4)>>14];
- blk[8*6] = iclp[(x3-x2)>>14];
- blk[8*7] = iclp[(x7-x1)>>14];
+ blk[8 * 0] = iclp[(x7 + x1) >> 14];
+ blk[8 * 1] = iclp[(x3 + x2) >> 14];
+ blk[8 * 2] = iclp[(x0 + x4) >> 14];
+ blk[8 * 3] = iclp[(x8 + x6) >> 14];
+ blk[8 * 4] = iclp[(x8 - x6) >> 14];
+ blk[8 * 5] = iclp[(x0 - x4) >> 14];
+ blk[8 * 6] = iclp[(x3 - x2) >> 14];
+ blk[8 * 7] = iclp[(x7 - x1) >> 14];
}
/* two dimensional inverse discrete cosine transform */
-void gst_idct_fast_int_idct(block)
-short *block;
+void
+gst_idct_fast_int_idct (block)
+ short *block;
{
int i;
- for (i=0; i<8; i++)
- idctrow(block+8*i);
+ for (i = 0; i < 8; i++)
+ idctrow (block + 8 * i);
- for (i=0; i<8; i++)
- idctcol(block+i);
+ for (i = 0; i < 8; i++)
+ idctcol (block + i);
}
-void gst_idct_init_fast_int_idct()
+void
+gst_idct_init_fast_int_idct ()
{
int i;
- iclp = iclip+512;
- for (i= -512; i<512; i++)
- iclp[i] = (i<-256) ? -256 : ((i>255) ? 255 : i);
+ iclp = iclip + 512;
+ for (i = -512; i < 512; i++)
+ iclp[i] = (i < -256) ? -256 : ((i > 255) ? 255 : i);
}
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