draw: factor out the Scale implementations.
This is just a copy/paste/rename in anticipation of automatically generating fast-path code for specific dst-image types and src-image types, a la the standard library's image/draw package. Change-Id: If6385b347cb5e1d134b0ce841ef38ed4450a6fef Reviewed-on: https://go-review.googlesource.com/5252 Reviewed-by: David Symonds <dsymonds@golang.org>
This commit is contained in:
Nigel Tao
parent
5869597f23
commit
2a1231edb8
165
draw/impl.go
Normal file
165
draw/impl.go
Normal file
|
|
@ -0,0 +1,165 @@
|
||||||
|
// Copyright 2015 The Go Authors. All rights reserved.
|
||||||
|
// Use of this source code is governed by a BSD-style
|
||||||
|
// license that can be found in the LICENSE file.
|
||||||
|
|
||||||
|
package draw
|
||||||
|
|
||||||
|
// TODO: autogenerate this file.
|
||||||
|
|
||||||
|
import (
|
||||||
|
"image"
|
||||||
|
"image/color"
|
||||||
|
)
|
||||||
|
|
||||||
|
func (z *nnScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) {
|
||||||
|
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
dstColorRGBA64 := &color.RGBA64{}
|
||||||
|
dstColor := color.Color(dstColorRGBA64)
|
||||||
|
for dy := int32(0); dy < z.dh; dy++ {
|
||||||
|
sy := (2*uint64(dy) + 1) * uint64(z.sh) / (2 * uint64(z.dh))
|
||||||
|
for dx := int32(0); dx < z.dw; dx++ {
|
||||||
|
sx := (2*uint64(dx) + 1) * uint64(z.sw) / (2 * uint64(z.dw))
|
||||||
|
pr, pg, pb, pa := src.At(sp.X+int(sx), sp.Y+int(sy)).RGBA()
|
||||||
|
dstColorRGBA64.R = uint16(pr)
|
||||||
|
dstColorRGBA64.G = uint16(pg)
|
||||||
|
dstColorRGBA64.B = uint16(pb)
|
||||||
|
dstColorRGBA64.A = uint16(pa)
|
||||||
|
dst.Set(dp.X+int(dx), dp.Y+int(dy), dstColor)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func (z *ablScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) {
|
||||||
|
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
yscale := float64(z.sh) / float64(z.dh)
|
||||||
|
xscale := float64(z.sw) / float64(z.dw)
|
||||||
|
dstColorRGBA64 := &color.RGBA64{}
|
||||||
|
dstColor := color.Color(dstColorRGBA64)
|
||||||
|
for dy := int32(0); dy < z.dh; dy++ {
|
||||||
|
sy := (float64(dy)+0.5)*yscale - 0.5
|
||||||
|
sy0 := int32(sy)
|
||||||
|
yFrac0 := sy - float64(sy0)
|
||||||
|
yFrac1 := 1 - yFrac0
|
||||||
|
sy1 := sy0 + 1
|
||||||
|
if sy < 0 {
|
||||||
|
sy0, sy1 = 0, 0
|
||||||
|
yFrac0, yFrac1 = 0, 1
|
||||||
|
} else if sy1 >= z.sh {
|
||||||
|
sy1 = sy0
|
||||||
|
yFrac0, yFrac1 = 1, 0
|
||||||
|
}
|
||||||
|
for dx := int32(0); dx < z.dw; dx++ {
|
||||||
|
sx := (float64(dx)+0.5)*xscale - 0.5
|
||||||
|
sx0 := int32(sx)
|
||||||
|
xFrac0 := sx - float64(sx0)
|
||||||
|
xFrac1 := 1 - xFrac0
|
||||||
|
sx1 := sx0 + 1
|
||||||
|
if sx < 0 {
|
||||||
|
sx0, sx1 = 0, 0
|
||||||
|
xFrac0, xFrac1 = 0, 1
|
||||||
|
} else if sx1 >= z.sw {
|
||||||
|
sx1 = sx0
|
||||||
|
xFrac0, xFrac1 = 1, 0
|
||||||
|
}
|
||||||
|
s00ru, s00gu, s00bu, s00au := src.At(sp.X+int(sx0), sp.Y+int(sy0)).RGBA()
|
||||||
|
s00r := float64(s00ru)
|
||||||
|
s00g := float64(s00gu)
|
||||||
|
s00b := float64(s00bu)
|
||||||
|
s00a := float64(s00au)
|
||||||
|
s10ru, s10gu, s10bu, s10au := src.At(sp.X+int(sx1), sp.Y+int(sy0)).RGBA()
|
||||||
|
s10r := float64(s10ru)
|
||||||
|
s10g := float64(s10gu)
|
||||||
|
s10b := float64(s10bu)
|
||||||
|
s10a := float64(s10au)
|
||||||
|
s10r = xFrac1*s00r + xFrac0*s10r
|
||||||
|
s10g = xFrac1*s00g + xFrac0*s10g
|
||||||
|
s10b = xFrac1*s00b + xFrac0*s10b
|
||||||
|
s10a = xFrac1*s00a + xFrac0*s10a
|
||||||
|
s01ru, s01gu, s01bu, s01au := src.At(sp.X+int(sx0), sp.Y+int(sy1)).RGBA()
|
||||||
|
s01r := float64(s01ru)
|
||||||
|
s01g := float64(s01gu)
|
||||||
|
s01b := float64(s01bu)
|
||||||
|
s01a := float64(s01au)
|
||||||
|
s11ru, s11gu, s11bu, s11au := src.At(sp.X+int(sx1), sp.Y+int(sy1)).RGBA()
|
||||||
|
s11r := float64(s11ru)
|
||||||
|
s11g := float64(s11gu)
|
||||||
|
s11b := float64(s11bu)
|
||||||
|
s11a := float64(s11au)
|
||||||
|
s11r = xFrac1*s01r + xFrac0*s11r
|
||||||
|
s11g = xFrac1*s01g + xFrac0*s11g
|
||||||
|
s11b = xFrac1*s01b + xFrac0*s11b
|
||||||
|
s11a = xFrac1*s01a + xFrac0*s11a
|
||||||
|
s11r = yFrac1*s10r + yFrac0*s11r
|
||||||
|
s11g = yFrac1*s10g + yFrac0*s11g
|
||||||
|
s11b = yFrac1*s10b + yFrac0*s11b
|
||||||
|
s11a = yFrac1*s10a + yFrac0*s11a
|
||||||
|
dstColorRGBA64.R = uint16(s11r)
|
||||||
|
dstColorRGBA64.G = uint16(s11g)
|
||||||
|
dstColorRGBA64.B = uint16(s11b)
|
||||||
|
dstColorRGBA64.A = uint16(s11a)
|
||||||
|
dst.Set(dp.X+int(dx), dp.Y+int(dy), dstColor)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func (z *kernelScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) {
|
||||||
|
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
// Create a temporary buffer:
|
||||||
|
// scaleX distributes the source image's columns over the temporary image.
|
||||||
|
// scaleY distributes the temporary image's rows over the destination image.
|
||||||
|
// TODO: is it worth having a sync.Pool for this temporary buffer?
|
||||||
|
tmp := make([][4]float64, z.dw*z.sh)
|
||||||
|
z.scaleX(tmp, src, sp)
|
||||||
|
z.scaleY(dst, dp, tmp)
|
||||||
|
}
|
||||||
|
|
||||||
|
func (z *kernelScaler) scaleX(tmp [][4]float64, src image.Image, sp image.Point) {
|
||||||
|
t := 0
|
||||||
|
for y := int32(0); y < z.sh; y++ {
|
||||||
|
for _, s := range z.horizontal.sources {
|
||||||
|
var r, g, b, a float64
|
||||||
|
for _, c := range z.horizontal.contribs[s.i:s.j] {
|
||||||
|
rr, gg, bb, aa := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA()
|
||||||
|
r += float64(rr) * c.weight
|
||||||
|
g += float64(gg) * c.weight
|
||||||
|
b += float64(bb) * c.weight
|
||||||
|
a += float64(aa) * c.weight
|
||||||
|
}
|
||||||
|
tmp[t] = [4]float64{
|
||||||
|
r * s.invTotalWeightFFFF,
|
||||||
|
g * s.invTotalWeightFFFF,
|
||||||
|
b * s.invTotalWeightFFFF,
|
||||||
|
a * s.invTotalWeightFFFF,
|
||||||
|
}
|
||||||
|
t++
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func (z *kernelScaler) scaleY(dst Image, dp image.Point, tmp [][4]float64) {
|
||||||
|
dstColorRGBA64 := &color.RGBA64{}
|
||||||
|
dstColor := color.Color(dstColorRGBA64)
|
||||||
|
for x := int32(0); x < z.dw; x++ {
|
||||||
|
for y, s := range z.vertical.sources {
|
||||||
|
var r, g, b, a float64
|
||||||
|
for _, c := range z.vertical.contribs[s.i:s.j] {
|
||||||
|
p := &tmp[c.coord*z.dw+x]
|
||||||
|
r += p[0] * c.weight
|
||||||
|
g += p[1] * c.weight
|
||||||
|
b += p[2] * c.weight
|
||||||
|
a += p[3] * c.weight
|
||||||
|
}
|
||||||
|
dstColorRGBA64.R = ftou(r * s.invTotalWeight)
|
||||||
|
dstColorRGBA64.G = ftou(g * s.invTotalWeight)
|
||||||
|
dstColorRGBA64.B = ftou(b * s.invTotalWeight)
|
||||||
|
dstColorRGBA64.A = ftou(a * s.invTotalWeight)
|
||||||
|
dst.Set(dp.X+int(x), dp.Y+y, dstColor)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
153
draw/scale.go
153
draw/scale.go
|
|
@ -8,7 +8,6 @@ package draw
|
||||||
|
|
||||||
import (
|
import (
|
||||||
"image"
|
"image"
|
||||||
"image/color"
|
|
||||||
"math"
|
"math"
|
||||||
)
|
)
|
||||||
|
|
||||||
|
|
@ -112,26 +111,6 @@ type nnScaler struct {
|
||||||
dw, dh, sw, sh int32
|
dw, dh, sw, sh int32
|
||||||
}
|
}
|
||||||
|
|
||||||
func (z *nnScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) {
|
|
||||||
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
|
|
||||||
return
|
|
||||||
}
|
|
||||||
dstColorRGBA64 := &color.RGBA64{}
|
|
||||||
dstColor := color.Color(dstColorRGBA64)
|
|
||||||
for dy := int32(0); dy < z.dh; dy++ {
|
|
||||||
sy := (2*uint64(dy) + 1) * uint64(z.sh) / (2 * uint64(z.dh))
|
|
||||||
for dx := int32(0); dx < z.dw; dx++ {
|
|
||||||
sx := (2*uint64(dx) + 1) * uint64(z.sw) / (2 * uint64(z.dw))
|
|
||||||
pr, pg, pb, pa := src.At(sp.X+int(sx), sp.Y+int(sy)).RGBA()
|
|
||||||
dstColorRGBA64.R = uint16(pr)
|
|
||||||
dstColorRGBA64.G = uint16(pg)
|
|
||||||
dstColorRGBA64.B = uint16(pb)
|
|
||||||
dstColorRGBA64.A = uint16(pa)
|
|
||||||
dst.Set(dp.X+int(dx), dp.Y+int(dy), dstColor)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
type ablInterpolator struct{}
|
type ablInterpolator struct{}
|
||||||
|
|
||||||
func (ablInterpolator) NewScaler(dw, dh, sw, sh int32) Scaler { return &ablScaler{dw, dh, sw, sh} }
|
func (ablInterpolator) NewScaler(dw, dh, sw, sh int32) Scaler { return &ablScaler{dw, dh, sw, sh} }
|
||||||
|
|
@ -140,96 +119,11 @@ type ablScaler struct {
|
||||||
dw, dh, sw, sh int32
|
dw, dh, sw, sh int32
|
||||||
}
|
}
|
||||||
|
|
||||||
func (z *ablScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) {
|
|
||||||
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
|
|
||||||
return
|
|
||||||
}
|
|
||||||
yscale := float64(z.sh) / float64(z.dh)
|
|
||||||
xscale := float64(z.sw) / float64(z.dw)
|
|
||||||
dstColorRGBA64 := &color.RGBA64{}
|
|
||||||
dstColor := color.Color(dstColorRGBA64)
|
|
||||||
for dy := int32(0); dy < z.dh; dy++ {
|
|
||||||
sy := (float64(dy)+0.5)*yscale - 0.5
|
|
||||||
sy0 := int32(sy)
|
|
||||||
yFrac0 := sy - float64(sy0)
|
|
||||||
yFrac1 := 1 - yFrac0
|
|
||||||
sy1 := sy0 + 1
|
|
||||||
if sy < 0 {
|
|
||||||
sy0, sy1 = 0, 0
|
|
||||||
yFrac0, yFrac1 = 0, 1
|
|
||||||
} else if sy1 >= z.sh {
|
|
||||||
sy1 = sy0
|
|
||||||
yFrac0, yFrac1 = 1, 0
|
|
||||||
}
|
|
||||||
for dx := int32(0); dx < z.dw; dx++ {
|
|
||||||
sx := (float64(dx)+0.5)*xscale - 0.5
|
|
||||||
sx0 := int32(sx)
|
|
||||||
xFrac0 := sx - float64(sx0)
|
|
||||||
xFrac1 := 1 - xFrac0
|
|
||||||
sx1 := sx0 + 1
|
|
||||||
if sx < 0 {
|
|
||||||
sx0, sx1 = 0, 0
|
|
||||||
xFrac0, xFrac1 = 0, 1
|
|
||||||
} else if sx1 >= z.sw {
|
|
||||||
sx1 = sx0
|
|
||||||
xFrac0, xFrac1 = 1, 0
|
|
||||||
}
|
|
||||||
s00ru, s00gu, s00bu, s00au := src.At(sp.X+int(sx0), sp.Y+int(sy0)).RGBA()
|
|
||||||
s00r := float64(s00ru)
|
|
||||||
s00g := float64(s00gu)
|
|
||||||
s00b := float64(s00bu)
|
|
||||||
s00a := float64(s00au)
|
|
||||||
s10ru, s10gu, s10bu, s10au := src.At(sp.X+int(sx1), sp.Y+int(sy0)).RGBA()
|
|
||||||
s10r := float64(s10ru)
|
|
||||||
s10g := float64(s10gu)
|
|
||||||
s10b := float64(s10bu)
|
|
||||||
s10a := float64(s10au)
|
|
||||||
s10r = xFrac1*s00r + xFrac0*s10r
|
|
||||||
s10g = xFrac1*s00g + xFrac0*s10g
|
|
||||||
s10b = xFrac1*s00b + xFrac0*s10b
|
|
||||||
s10a = xFrac1*s00a + xFrac0*s10a
|
|
||||||
s01ru, s01gu, s01bu, s01au := src.At(sp.X+int(sx0), sp.Y+int(sy1)).RGBA()
|
|
||||||
s01r := float64(s01ru)
|
|
||||||
s01g := float64(s01gu)
|
|
||||||
s01b := float64(s01bu)
|
|
||||||
s01a := float64(s01au)
|
|
||||||
s11ru, s11gu, s11bu, s11au := src.At(sp.X+int(sx1), sp.Y+int(sy1)).RGBA()
|
|
||||||
s11r := float64(s11ru)
|
|
||||||
s11g := float64(s11gu)
|
|
||||||
s11b := float64(s11bu)
|
|
||||||
s11a := float64(s11au)
|
|
||||||
s11r = xFrac1*s01r + xFrac0*s11r
|
|
||||||
s11g = xFrac1*s01g + xFrac0*s11g
|
|
||||||
s11b = xFrac1*s01b + xFrac0*s11b
|
|
||||||
s11a = xFrac1*s01a + xFrac0*s11a
|
|
||||||
s11r = yFrac1*s10r + yFrac0*s11r
|
|
||||||
s11g = yFrac1*s10g + yFrac0*s11g
|
|
||||||
s11b = yFrac1*s10b + yFrac0*s11b
|
|
||||||
s11a = yFrac1*s10a + yFrac0*s11a
|
|
||||||
dstColorRGBA64.R = uint16(s11r)
|
|
||||||
dstColorRGBA64.G = uint16(s11g)
|
|
||||||
dstColorRGBA64.B = uint16(s11b)
|
|
||||||
dstColorRGBA64.A = uint16(s11a)
|
|
||||||
dst.Set(dp.X+int(dx), dp.Y+int(dy), dstColor)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
type kernelScaler struct {
|
type kernelScaler struct {
|
||||||
dw, dh, sw, sh int32
|
dw, dh, sw, sh int32
|
||||||
horizontal, vertical distrib
|
horizontal, vertical distrib
|
||||||
}
|
}
|
||||||
|
|
||||||
func (z *kernelScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Point) {
|
|
||||||
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
|
|
||||||
return
|
|
||||||
}
|
|
||||||
// TODO: is it worth having a sync.Pool for this temporary buffer?
|
|
||||||
tmp := make([][4]float64, z.dw*z.sh)
|
|
||||||
z.scaleX(tmp, src, sp)
|
|
||||||
z.scaleY(dst, dp, tmp)
|
|
||||||
}
|
|
||||||
|
|
||||||
// source is a range of contribs, their inverse total weight, and that ITW
|
// source is a range of contribs, their inverse total weight, and that ITW
|
||||||
// divided by 0xffff.
|
// divided by 0xffff.
|
||||||
type source struct {
|
type source struct {
|
||||||
|
|
@ -317,53 +211,6 @@ func newDistrib(q *Kernel, dw, sw int32) distrib {
|
||||||
return distrib{sources, contribs}
|
return distrib{sources, contribs}
|
||||||
}
|
}
|
||||||
|
|
||||||
// scaleX distributes the source image's columns over the temporary image.
|
|
||||||
func (z *kernelScaler) scaleX(tmp [][4]float64, src image.Image, sp image.Point) {
|
|
||||||
t := 0
|
|
||||||
for y := int32(0); y < z.sh; y++ {
|
|
||||||
for _, s := range z.horizontal.sources {
|
|
||||||
var r, g, b, a float64
|
|
||||||
for _, c := range z.horizontal.contribs[s.i:s.j] {
|
|
||||||
rr, gg, bb, aa := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA()
|
|
||||||
r += float64(rr) * c.weight
|
|
||||||
g += float64(gg) * c.weight
|
|
||||||
b += float64(bb) * c.weight
|
|
||||||
a += float64(aa) * c.weight
|
|
||||||
}
|
|
||||||
tmp[t] = [4]float64{
|
|
||||||
r * s.invTotalWeightFFFF,
|
|
||||||
g * s.invTotalWeightFFFF,
|
|
||||||
b * s.invTotalWeightFFFF,
|
|
||||||
a * s.invTotalWeightFFFF,
|
|
||||||
}
|
|
||||||
t++
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
// scaleY distributes the temporary image's rows over the destination image.
|
|
||||||
func (z *kernelScaler) scaleY(dst Image, dp image.Point, tmp [][4]float64) {
|
|
||||||
dstColorRGBA64 := &color.RGBA64{}
|
|
||||||
dstColor := color.Color(dstColorRGBA64)
|
|
||||||
for x := int32(0); x < z.dw; x++ {
|
|
||||||
for y, s := range z.vertical.sources {
|
|
||||||
var r, g, b, a float64
|
|
||||||
for _, c := range z.vertical.contribs[s.i:s.j] {
|
|
||||||
p := &tmp[c.coord*z.dw+x]
|
|
||||||
r += p[0] * c.weight
|
|
||||||
g += p[1] * c.weight
|
|
||||||
b += p[2] * c.weight
|
|
||||||
a += p[3] * c.weight
|
|
||||||
}
|
|
||||||
dstColorRGBA64.R = ftou(r * s.invTotalWeight)
|
|
||||||
dstColorRGBA64.G = ftou(g * s.invTotalWeight)
|
|
||||||
dstColorRGBA64.B = ftou(b * s.invTotalWeight)
|
|
||||||
dstColorRGBA64.A = ftou(a * s.invTotalWeight)
|
|
||||||
dst.Set(dp.X+int(x), dp.Y+y, dstColor)
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
func ftou(f float64) uint16 {
|
func ftou(f float64) uint16 {
|
||||||
i := int32(0xffff*f + 0.5)
|
i := int32(0xffff*f + 0.5)
|
||||||
if i > 0xffff {
|
if i > 0xffff {
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue
Block a user