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naive implementation

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Alexander 2019-11-24 17:40:05 +03:00
parent 335f5431de
commit 01094a9649
1 changed files with 114 additions and 1 deletions
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115
src/libImaging/Reduce.c
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@ -5,12 +5,125 @@
#define ROUND_UP(f) ((int) ((f) >= 0.0 ? (f) + 0.5F : (f) - 0.5F))
void
ImagingReduce2x2(Imaging imOut, Imaging imIn)
{
ImagingSectionCookie cookie;
int x, y;
int ss0, ss1, ss2, ss3;
ImagingSectionEnter(&cookie);
if (imIn->image8) {
} else {
switch(imIn->type) {
case IMAGING_TYPE_UINT8:
for (y = 0; y < imIn->ysize / 2; y++) {
UINT8 *line0 = (UINT8 *)imIn->image[y*2 + 0];
UINT8 *line1 = (UINT8 *)imIn->image[y*2 + 1];
if (imIn->bands == 2) {
} else if (imIn->bands == 3) {
for (x = 0; x < imIn->xsize / 2; x++) {
UINT32 v;
ss0 = line0[x*2*4 + 0] + line0[x*2*4 + 4] +
line1[x*2*4 + 0] + line1[x*2*4 + 4];
ss1 = line0[x*2*4 + 1] + line0[x*2*4 + 5] +
line1[x*2*4 + 1] + line1[x*2*4 + 5];
ss2 = line0[x*2*4 + 2] + line0[x*2*4 + 6] +
line1[x*2*4 + 2] + line1[x*2*4 + 6];
v = MAKE_UINT32((ss0 + 2) >> 2, (ss1 + 2) >> 2,
(ss2 + 2) >> 2, 0);
memcpy(imOut->image[y] + x * sizeof(v), &v, sizeof(v));
}
} else { // bands == 4
}
}
break;
case IMAGING_TYPE_INT32:
break;
case IMAGING_TYPE_FLOAT32:
break;
}
}
ImagingSectionLeave(&cookie);
}
void
ImagingReduce4x4(Imaging imOut, Imaging imIn)
{
ImagingSectionCookie cookie;
int x, y;
int ss0, ss1, ss2, ss3;
ImagingSectionEnter(&cookie);
if (imIn->image8) {
} else {
switch(imIn->type) {
case IMAGING_TYPE_UINT8:
for (y = 0; y < imIn->ysize / 4; y++) {
UINT8 *line0 = (UINT8 *)imIn->image[y*4 + 0];
UINT8 *line1 = (UINT8 *)imIn->image[y*4 + 1];
UINT8 *line2 = (UINT8 *)imIn->image[y*4 + 2];
UINT8 *line3 = (UINT8 *)imIn->image[y*4 + 3];
if (imIn->bands == 2) {
} else if (imIn->bands == 3) {
for (x = 0; x < imIn->xsize / 4; x++) {
UINT32 v;
ss0 = line0[x*4*4 + 0] + line0[x*4*4 + 4] + line0[x*4*4 + 8] + line0[x*4*4 + 12] +
line1[x*4*4 + 0] + line1[x*4*4 + 4] + line1[x*4*4 + 8] + line1[x*4*4 + 12] +
line2[x*4*4 + 0] + line2[x*4*4 + 4] + line2[x*4*4 + 8] + line2[x*4*4 + 12] +
line3[x*4*4 + 0] + line3[x*4*4 + 4] + line3[x*4*4 + 8] + line3[x*4*4 + 12];
ss1 = line0[x*4*4 + 1] + line0[x*4*4 + 5] + line0[x*4*4 + 9] + line0[x*4*4 + 13] +
line1[x*4*4 + 1] + line1[x*4*4 + 5] + line1[x*4*4 + 9] + line1[x*4*4 + 13] +
line2[x*4*4 + 1] + line2[x*4*4 + 5] + line2[x*4*4 + 9] + line2[x*4*4 + 13] +
line3[x*4*4 + 1] + line3[x*4*4 + 5] + line3[x*4*4 + 9] + line3[x*4*4 + 13];
ss2 = line0[x*4*4 + 2] + line0[x*4*4 + 6] + line0[x*4*4 + 10] + line0[x*4*4 + 14] +
line1[x*4*4 + 2] + line1[x*4*4 + 6] + line1[x*4*4 + 10] + line1[x*4*4 + 14] +
line2[x*4*4 + 2] + line2[x*4*4 + 6] + line2[x*4*4 + 10] + line2[x*4*4 + 14] +
line3[x*4*4 + 2] + line3[x*4*4 + 6] + line3[x*4*4 + 10] + line3[x*4*4 + 14];
v = MAKE_UINT32((ss0 + 8) >> 4, (ss1 + 8) >> 4,
(ss2 + 8) >> 4, 0);
memcpy(imOut->image[y] + x * sizeof(v), &v, sizeof(v));
}
} else { // bands == 4
}
}
break;
case IMAGING_TYPE_INT32:
break;
case IMAGING_TYPE_FLOAT32:
break;
}
}
ImagingSectionLeave(&cookie);
}
Imaging
ImagingReduce(Imaging imIn, int xscale, int yscale)
{
Imaging imOut = NULL;
imOut = ImagingNewDirty(imIn->mode, imIn->xsize, imIn->ysize);
imOut = ImagingNewDirty(imIn->mode,
(imIn->xsize + xscale - 1) / xscale,
(imIn->ysize + yscale - 1) / yscale);
if (xscale == 2 && yscale == 2) {
ImagingReduce2x2(imOut, imIn);
} else if (xscale == 4 && yscale == 4) {
ImagingReduce4x4(imOut, imIn);
}
return imOut;
}