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Reintroduce lost idctSparseCol for Alpha. Sorry for adding even more 

code duplication, I'm currently working on the put/add variants, but I
did not get them to be as fast as the old method yet...

Originally committed as revision 703 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Falk Hüffner 2002-06-24 21:17:22 +00:00
parent 5ac80202c8
commit 3155c994b6
1 changed files with 73 additions and 0 deletions
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73
libavcodec/simple_idct.c
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@ -167,6 +167,79 @@ static inline int idctRowCondDC(int16_t *row)
return 2;
}
inline static void idctSparseCol(int16_t *col)
{
int a0, a1, a2, a3, b0, b1, b2, b3;
col[0] += (1 << (COL_SHIFT - 1)) / W4;
a0 = W4 * col[8 * 0];
a1 = W4 * col[8 * 0];
a2 = W4 * col[8 * 0];
a3 = W4 * col[8 * 0];
if (col[8 * 2]) {
a0 += W2 * col[8 * 2];
a1 += W6 * col[8 * 2];
a2 -= W6 * col[8 * 2];
a3 -= W2 * col[8 * 2];
}
if (col[8 * 4]) {
a0 += W4 * col[8 * 4];
a1 -= W4 * col[8 * 4];
a2 -= W4 * col[8 * 4];
a3 += W4 * col[8 * 4];
}
if (col[8 * 6]) {
a0 += W6 * col[8 * 6];
a1 -= W2 * col[8 * 6];
a2 += W2 * col[8 * 6];
a3 -= W6 * col[8 * 6];
}
if (col[8 * 1]) {
b0 = W1 * col[8 * 1];
b1 = W3 * col[8 * 1];
b2 = W5 * col[8 * 1];
b3 = W7 * col[8 * 1];
} else {
b0 = b1 = b2 = b3 = 0;
}
if (col[8 * 3]) {
b0 += W3 * col[8 * 3];
b1 -= W7 * col[8 * 3];
b2 -= W1 * col[8 * 3];
b3 -= W5 * col[8 * 3];
}
if (col[8 * 5]) {
b0 += W5 * col[8 * 5];
b1 -= W1 * col[8 * 5];
b2 += W7 * col[8 * 5];
b3 += W3 * col[8 * 5];
}
if (col[8 * 7]) {
b0 += W7 * col[8 * 7];
b1 -= W5 * col[8 * 7];
b2 += W3 * col[8 * 7];
b3 -= W1 * col[8 * 7];
}
col[8 * 0] = (a0 + b0) >> COL_SHIFT;
col[8 * 7] = (a0 - b0) >> COL_SHIFT;
col[8 * 1] = (a1 + b1) >> COL_SHIFT;
col[8 * 6] = (a1 - b1) >> COL_SHIFT;
col[8 * 2] = (a2 + b2) >> COL_SHIFT;
col[8 * 5] = (a2 - b2) >> COL_SHIFT;
col[8 * 3] = (a3 + b3) >> COL_SHIFT;
col[8 * 4] = (a3 - b3) >> COL_SHIFT;
}
#else /* not ARCH_ALPHA */
static inline void idctRowCondDC (int16_t * row)