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pure FPI implementation

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Alexander 2018-03-26 17:23:14 +03:00
parent 23827d5250
commit 3a5f0201f5
1 changed files with 36 additions and 29 deletions
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65
src/libImaging/ColorLUT.c
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@ -8,6 +8,14 @@
#define PRECISION_BITS (16 - 8 - 2)
#define PRECISION_ROUNDING (1<<(PRECISION_BITS-1))
/* 8 — scales are multiplyed on byte.
6 — max index in the table (size is 65, but index 64 is not reachable) */
#define SCALE_BITS (32 - 8 - 6)
#define SCALE_MASK ((1 << SCALE_BITS) - 1)
#define SHIFT_BITS (16 - 1)
#define SHIFT_ROUNDING (1<<(SHIFT_BITS-1))
UINT8 _lookups2[1024] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
@ -88,18 +96,18 @@ static inline UINT8 clip8(int in)
static inline void
interpolate3(INT16 out[3], const INT16 a[3], const INT16 b[3], INT16 shift)
{
out[0] = (a[0] * (0x1000-shift) + b[0] * shift + (1<<11)) >> 12;
out[1] = (a[1] * (0x1000-shift) + b[1] * shift + (1<<11)) >> 12;
out[2] = (a[2] * (0x1000-shift) + b[2] * shift + (1<<11)) >> 12;
out[0] = (a[0] * ((1<<SHIFT_BITS)-shift) + b[0] * shift + SHIFT_ROUNDING) >> SHIFT_BITS;
out[1] = (a[1] * ((1<<SHIFT_BITS)-shift) + b[1] * shift + SHIFT_ROUNDING) >> SHIFT_BITS;
out[2] = (a[2] * ((1<<SHIFT_BITS)-shift) + b[2] * shift + SHIFT_ROUNDING) >> SHIFT_BITS;
}
static inline void
interpolate4(INT16 out[4], const INT16 a[4], const INT16 b[4], INT16 shift)
{
out[0] = (a[0] * (0x1000-shift) + b[0] * shift + (1<<11)) >> 12;
out[1] = (a[1] * (0x1000-shift) + b[1] * shift + (1<<11)) >> 12;
out[2] = (a[2] * (0x1000-shift) + b[2] * shift + (1<<11)) >> 12;
out[3] = (a[3] * (0x1000-shift) + b[3] * shift + (1<<11)) >> 12;
out[0] = (a[0] * ((1<<SHIFT_BITS)-shift) + b[0] * shift + SHIFT_ROUNDING) >> SHIFT_BITS;
out[1] = (a[1] * ((1<<SHIFT_BITS)-shift) + b[1] * shift + SHIFT_ROUNDING) >> SHIFT_BITS;
out[2] = (a[2] * ((1<<SHIFT_BITS)-shift) + b[2] * shift + SHIFT_ROUNDING) >> SHIFT_BITS;
out[3] = (a[3] * ((1<<SHIFT_BITS)-shift) + b[3] * shift + SHIFT_ROUNDING) >> SHIFT_BITS;
}
static inline int
@ -143,9 +151,9 @@ ImagingColorLUT3D_linear(Imaging imOut, Imaging imIn, int table_channels,
+1 cells will be outside of the table.
With this compensation we never hit the upper cells
but this also doesn't introduce any noticable difference. */
float scale1D = (size1D - 1) / (255.0002);
float scale2D = (size2D - 1) / (255.0002);
float scale3D = (size3D - 1) / (255.0002);
UINT32 scale1D = (size1D - 1) / 255.0 * (1<<SCALE_BITS);
UINT32 scale2D = (size2D - 1) / 255.0 * (1<<SCALE_BITS);
UINT32 scale3D = (size3D - 1) / 255.0 * (1<<SCALE_BITS);
int size1D_2D = size1D * size2D;
int x, y;
@ -169,18 +177,19 @@ ImagingColorLUT3D_linear(Imaging imOut, Imaging imIn, int table_channels,
for (y = 0; y < imOut->ysize; y++) {
UINT8* rowIn = (UINT8 *)imIn->image[y];
UINT8* rowOut = (UINT8 *)imOut->image[y];
UINT32* rowOut = (UINT32 *)imOut->image[y];
for (x = 0; x < imOut->xsize; x++) {
float scaled1D = rowIn[x*4 + 0] * scale1D;
float scaled2D = rowIn[x*4 + 1] * scale2D;
float scaled3D = rowIn[x*4 + 2] * scale3D;
int index1D = (int) scaled1D;
int index2D = (int) scaled2D;
int index3D = (int) scaled3D;
INT16 shift1D = (scaled1D - index1D) * 0x1000 + 0.5;
INT16 shift2D = (scaled2D - index2D) * 0x1000 + 0.5;
INT16 shift3D = (scaled3D - index3D) * 0x1000 + 0.5;
int idx = table3D_index3(index1D, index2D, index3D, size1D, size1D_2D);
UINT32 index1D = rowIn[x*4 + 0] * scale1D;
UINT32 index2D = rowIn[x*4 + 1] * scale2D;
UINT32 index3D = rowIn[x*4 + 2] * scale3D;
INT16 shift1D = (SCALE_MASK & index1D) >> (SCALE_BITS - SHIFT_BITS);
INT16 shift2D = (SCALE_MASK & index2D) >> (SCALE_BITS - SHIFT_BITS);
INT16 shift3D = (SCALE_MASK & index3D) >> (SCALE_BITS - SHIFT_BITS);
int idx = table3D_index3(
index1D >> SCALE_BITS,
index2D >> SCALE_BITS,
index3D >> SCALE_BITS,
size1D, size1D_2D);
INT16 result[4], left[4], right[4];
INT16 leftleft[4], leftright[4], rightleft[4], rightright[4];
@ -198,10 +207,9 @@ ImagingColorLUT3D_linear(Imaging imOut, Imaging imIn, int table_channels,
interpolate3(result, left, right, shift3D);
rowOut[x*4 + 0] = clip8(result[0]);
rowOut[x*4 + 1] = clip8(result[1]);
rowOut[x*4 + 2] = clip8(result[2]);
rowOut[x*4 + 3] = rowIn[x*4 + 3];
rowOut[x] = MAKE_UINT32(
clip8(result[0]), clip8(result[1]),
clip8(result[2]), rowIn[x*4 + 3]);
}
if (table_channels == 4) {
@ -218,10 +226,9 @@ ImagingColorLUT3D_linear(Imaging imOut, Imaging imIn, int table_channels,
interpolate4(result, left, right, shift3D);
rowOut[x*4 + 0] = clip8(result[0]);
rowOut[x*4 + 1] = clip8(result[1]);
rowOut[x*4 + 2] = clip8(result[2]);
rowOut[x*4 + 3] = clip8(result[3]);
rowOut[x] = MAKE_UINT32(
clip8(result[0]), clip8(result[1]),
clip8(result[2]), clip8(result[3]));
}
}
}