diff options
Diffstat (limited to 'media-gfx/xv/files/xv-smoothing-algorithm.diff')
| -rw-r--r-- | media-gfx/xv/files/xv-smoothing-algorithm.diff | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/media-gfx/xv/files/xv-smoothing-algorithm.diff b/media-gfx/xv/files/xv-smoothing-algorithm.diff new file mode 100644 index 000000000000..e5516966a5eb --- /dev/null +++ b/media-gfx/xv/files/xv-smoothing-algorithm.diff @@ -0,0 +1,172 @@ +diff -urN old/xv-3.10a/xvsmooth.c xv-3.10a/xvsmooth.c +--- old/xv-3.10a/xvsmooth.c Thu Dec 22 17:34:42 1994 ++++ xv-3.10a/xvsmooth.c Sun Aug 17 14:07:58 1997 +@@ -65,10 +65,13 @@ + returns a dwide*dhigh 24bit image, or NULL on failure (malloc) */ + /* rmap,gmap,bmap should be 'desired' colors */ + ++ /* DANGER: This code assumes that a right-shift on signed integers is ++ performed arithmetically, i.e. the sign bit is copied to the right. */ ++ + byte *pic24, *pp; +- int *cxtab, *pxtab; +- int y1Off, cyOff; +- int ex, ey, cx, cy, px, py, apx, apy, x1, y1; ++ int *pxtab; ++ int ex, ey, px, py, x0, x1, y0, y1; ++ int y0off, y1off; + int cA, cB, cC, cD; + int pA, pB, pC, pD; + int retval, bperpix; +@@ -98,69 +101,61 @@ + else { + /* dwide >= swide && dhigh >= shigh */ + +- /* cx,cy = original pixel in pic824. px,py = relative position +- of pixel ex,ey inside of cx,cy as percentages +-50%, +-50%. +- 0,0 = middle of pixel */ +- +- /* we can save a lot of time by precomputing cxtab[] and pxtab[], both +- dwide arrays of ints that contain values for the equations: +- cx = (ex * swide) / dwide; +- px = ((ex * swide * 100) / dwide) - (cx * 100) - 50; */ +- +- cxtab = (int *) malloc(dwide * sizeof(int)); +- if (!cxtab) { free(pic24); return NULL; } ++ /* px, py = location on original image, in units of 1/256 pixel ++ We can save time by precomputing all values of px. */ + + pxtab = (int *) malloc(dwide * sizeof(int)); +- if (!pxtab) { free(pic24); free(cxtab); return NULL; } +- +- for (ex=0; ex<dwide; ex++) { +- cxtab[ex] = (ex * swide) / dwide; +- pxtab[ex] = (((ex * swide)* 100) / dwide) +- - (cxtab[ex] * 100) - 50; +- } ++ if (!pxtab) { free(pic24); return NULL; } + +- for (ey=0; ey<dhigh; ey++) { ++ for (ex=0; ex < dwide; ex++) ++ pxtab[ex] = ((ex << 8) + 128) * swide / dwide - 128; ++ ++ for (ey=0; ey < dhigh; ey++) { + byte *pptr, rA, gA, bA, rB, gB, bB, rC, gC, bC, rD, gD, bD; + + ProgressMeter(0, (dhigh)-1, ey, "Smooth"); + +- cy = (ey * shigh) / dhigh; +- py = (((ey * shigh) * 100) / dhigh) - (cy * 100) - 50; +- if (py<0) { y1 = cy-1; if (y1<0) y1=0; } +- else { y1 = cy+1; if (y1>shigh-1) y1=shigh-1; } ++ py = ((ey << 8) + 128) * shigh / dhigh - 128; ++ y0 = py >> 8; /* Put integer part in y0 */ ++ y1 = y0 + 1; ++ py &= 255; /* Keep fractional part in py */ ++ ++ if (y0 < 0) y0 = y1 = 0; ++ if (y1 >= shigh) y0 = y1 = shigh-1; + +- cyOff = cy * swide * bperpix; /* current line */ +- y1Off = y1 * swide * bperpix; /* up or down one line, depending */ ++ y0off = y0 * swide * bperpix; /* current line */ ++ y1off = y1 * swide * bperpix; /* one line down */ + + if ((ey&15) == 0) WaitCursor(); + +- for (ex=0; ex<dwide; ex++) { +- rA = rB = rC = rD = gA = gB = gC = gD = bA = bB = bC = bD = 0; ++ for (ex=0; ex < dwide; ex++) { + +- cx = cxtab[ex]; + px = pxtab[ex]; ++ x0 = px >> 8; /* Put integer part in x0 */ ++ x1 = x0 + 1; ++ px &= 255; /* Keep fractional part in px */ + +- if (px<0) { x1 = cx-1; if (x1<0) x1=0; } +- else { x1 = cx+1; if (x1>swide-1) x1=swide-1; } ++ if (x0 < 0) x0 = x1 = 0; ++ if (x1 >= swide) x0 = x1 = swide-1; + + if (is24) { +- pptr = pic824 + y1Off + x1*bperpix; /* corner pixel */ ++ pptr = pic824 + y0off + x0*bperpix; /* upper left pixel */ + rA = *pptr++; gA = *pptr++; bA = *pptr++; + +- pptr = pic824 + y1Off + cx*bperpix; /* up/down center pixel */ ++ pptr = pic824 + y0off + x1*bperpix; /* upper right pixel */ + rB = *pptr++; gB = *pptr++; bB = *pptr++; + +- pptr = pic824 + cyOff + x1*bperpix; /* left/right center pixel */ ++ pptr = pic824 + y1off + x0*bperpix; /* lower left pixel */ + rC = *pptr++; gC = *pptr++; bC = *pptr++; + +- pptr = pic824 + cyOff + cx*bperpix; /* center pixel */ ++ pptr = pic824 + y1off + x1*bperpix; /* lower right pixel */ + rD = *pptr++; gD = *pptr++; bD = *pptr++; + } + else { /* 8-bit picture */ +- cA = pic824[y1Off + x1]; /* corner pixel */ +- cB = pic824[y1Off + cx]; /* up/down center pixel */ +- cC = pic824[cyOff + x1]; /* left/right center pixel */ +- cD = pic824[cyOff + cx]; /* center pixel */ ++ cA = pic824[y0off + x0]; /* upper left pixel */ ++ cB = pic824[y0off + x1]; /* upper right pixel */ ++ cC = pic824[y1off + x0]; /* lower left pixel */ ++ cD = pic824[y1off + x1]; /* lower right pixel */ + } + + /* quick check */ +@@ -170,38 +165,30 @@ + } + + else { +- /* compute weighting factors */ +- apx = abs(px); apy = abs(py); +- pA = (apx * apy) / 100; +- pB = (apy * (100 - apx)) / 100; +- pC = (apx * (100 - apy)) / 100; +- pD = 100 - (pA + pB + pC); ++ pA = (256-px)*(256-py); /* compute weighting factors */ ++ pB = px * (256-py); /* total weight is exactly 2^16 */ ++ pC = (256-px) * py; ++ pD = px * py; + + if (is24) { +- *pp++ = ((int) (pA * rA))/100 + ((int) (pB * rB))/100 + +- ((int) (pC * rC))/100 + ((int) (pD * rD))/100; +- +- *pp++ = ((int) (pA * gA))/100 + ((int) (pB * gB))/100 + +- ((int) (pC * gC))/100 + ((int) (pD * gD))/100; +- +- *pp++ = ((int) (pA * bA))/100 + ((int) (pB * bB))/100 + +- ((int) (pC * bC))/100 + ((int) (pD * bD))/100; ++ *pp++ = (pA * rA + pB * rB + pC * rC + pD * rD) + 32768 >> 16; ++ *pp++ = (pA * gA + pB * gB + pC * gC + pD * gD) + 32768 >> 16; ++ *pp++ = (pA * bA + pB * bB + pC * bC + pD * bD) + 32768 >> 16; + } + else { /* 8-bit pic */ +- *pp++ = ((int) (pA * rmap[cA]))/100 + ((int)(pB * rmap[cB]))/100 + +- ((int) (pC * rmap[cC]))/100 + ((int)(pD * rmap[cD]))/100; ++ *pp++ = (pA * rmap[cA] + pB * rmap[cB] + pC * rmap[cC] + ++ pD * rmap[cD]) + 32768 >> 16; + +- *pp++ = ((int) (pA * gmap[cA]))/100 + ((int)(pB * gmap[cB]))/100 + +- ((int) (pC * gmap[cC]))/100 + ((int)(pD * gmap[cD]))/100; ++ *pp++ = (pA * gmap[cA] + pB * gmap[cB] + pC * gmap[cC] + ++ pD * gmap[cD]) + 32768 >> 16; + +- *pp++ = ((int)(pA * bmap[cA]))/100 + ((int)(pB * bmap[cB]))/100 + +- ((int)(pC * bmap[cC]))/100 + ((int)(pD * bmap[cD]))/100; ++ *pp++ = (pA * bmap[cA] + pB * bmap[cB] + pC * bmap[cC] + ++ pD * bmap[cD]) + 32768 >> 16; + } + } + } + } + +- free(cxtab); + free(pxtab); + retval = 0; /* okay */ + } |