draw: generate impl.go type switches.

This just the type switches to concrete-type-specific methods.
Generating RGBA- or YCbCr-specific code instead of calling the
general-purpose At and Set methods will be follow-up changes.

benchmark                     old ns/op      new ns/op      delta
BenchmarkScaleLargeDownNN     5771212        5766160        -0.09%
BenchmarkScaleLargeDownAB     14057354       14023083       -0.24%
BenchmarkScaleLargeDownBL     1349968635     1347746478     -0.16%
BenchmarkScaleLargeDownCR     2687753329     2678909022     -0.33%
BenchmarkScaleDownNN          1802408        1808723        +0.35%
BenchmarkScaleDownAB          4352978        4284878        -1.56%
BenchmarkScaleDownBL          29760913       29522171       -0.80%
BenchmarkScaleDownCR          57666917       56334005       -2.31%
BenchmarkScaleUpNN            88886450       89235790       +0.39%
BenchmarkScaleUpAB            214687758      213797857      -0.41%
BenchmarkScaleUpBL            119588096      119846371      +0.22%
BenchmarkScaleUpCR            179784111      180662030      +0.49%
BenchmarkScaleSrcUniform      4128528        3855385        -6.62%
BenchmarkScaleSrcNRGBA        13275457       13375039       +0.75%
BenchmarkScaleSrcRGBA         13333672       12812895       -3.91%
BenchmarkScaleSrcYCbCr        14321945       14139071       -1.28%

Change-Id: I28025c3b49186a12d20ee0182a4c8ff9b036d0ae
Reviewed-on: https://go-review.googlesource.com/5712
Reviewed-by: Rob Pike <r@golang.org>
This commit is contained in:
Nigel Tao 2015-02-24 15:28:16 +11:00
parent 999c3975a8
commit 748adb17a1
3 changed files with 798 additions and 99 deletions

View File

@ -43,13 +43,39 @@ func main() {
}
}
// dsTypes are the space-separated (dst image type, src image type) pairs to
// generate scale_DType_SType implementations for. The last element in the
// slice should be the fallback pair "Image image.Image".
//
// TODO: add more concrete types: *image.RGBA, *image.YCbCr, etc.
var dsTypes = []string{
"Image image.Image",
var (
// dsTypes are the (dst image type, src image type) pairs to generate
// scale_DType_SType implementations for. The last element in the slice
// should be the fallback pair ("Image", "image.Image").
//
// TODO: add *image.CMYK src type after Go 1.5 is released.
dsTypes = []struct{ dType, sType string }{
{"*image.RGBA", "*image.NRGBA"},
{"*image.RGBA", "*image.RGBA"},
{"*image.RGBA", "*image.Uniform"},
{"*image.RGBA", "*image.YCbCr"},
{"*image.RGBA", "image.Image"},
{"Image", "image.Image"},
}
dTypes, sTypes []string
sTypesForDType = map[string][]string{}
)
func init() {
dTypesSeen := map[string]bool{}
sTypesSeen := map[string]bool{}
for _, t := range dsTypes {
if !sTypesSeen[t.sType] {
sTypesSeen[t.sType] = true
sTypes = append(sTypes, t.sType)
}
if !dTypesSeen[t.dType] {
dTypesSeen[t.dType] = true
dTypes = append(dTypes, t.dType)
}
sTypesForDType[t.dType] = append(sTypesForDType[t.dType], t.sType)
}
sTypesForDType["anyDType"] = sTypes
}
type data struct {
@ -60,12 +86,10 @@ type data struct {
func gen(w *bytes.Buffer, receiver string, code string) {
expn(w, codeRoot, &data{receiver: receiver})
for _, dsType := range dsTypes {
dType, sType := split(dsType, " ")
for _, t := range dsTypes {
expn(w, code, &data{
dType: dType,
sType: sType,
dType: t.dType,
sType: t.sType,
receiver: receiver,
})
}
@ -73,55 +97,51 @@ func gen(w *bytes.Buffer, receiver string, code string) {
func genKernel(w *bytes.Buffer) {
expn(w, codeKernelRoot, &data{})
dTypesSeen := map[string]bool{}
sTypesSeen := map[string]bool{}
for _, dsType := range dsTypes {
dType, sType := split(dsType, " ")
if !sTypesSeen[sType] {
sTypesSeen[sType] = true
expn(w, codeKernelLeafX, &data{
sType: sType,
})
}
if !dTypesSeen[dType] {
dTypesSeen[dType] = true
expn(w, codeKernelLeafY, &data{
dType: dType,
})
}
for _, sType := range sTypes {
expn(w, codeKernelLeafX, &data{
sType: sType,
})
}
for _, dType := range dTypes {
expn(w, codeKernelLeafY, &data{
dType: dType,
})
}
}
func expn(w *bytes.Buffer, code string, d *data) {
for _, line := range strings.Split(code, "\n") {
for {
i := strings.IndexByte(line, '$')
if i < 0 {
break
}
prefix, s := line[:i], line[i+1:]
i = len(s)
for j, c := range s {
if !('A' <= c && c <= 'Z' || 'a' <= c && c <= 'z') {
i = j
break
}
}
dollar, suffix := s[:i], s[i:]
e := expnLine(prefix, dollar, suffix, d)
if e == "" {
log.Fatalf("couldn't expand %q", line)
}
line = e
}
fmt.Fprintln(w, line)
fmt.Fprintln(w, expnLine(line, d))
}
}
func expnLine(prefix, dollar, suffix string, d *data) string {
func expnLine(line string, d *data) string {
for {
i := strings.IndexByte(line, '$')
if i < 0 {
break
}
prefix, s := line[:i], line[i+1:]
i = len(s)
for j, c := range s {
if !('A' <= c && c <= 'Z' || 'a' <= c && c <= 'z') {
i = j
break
}
}
dollar, suffix := s[:i], s[i:]
e := expnDollar(prefix, dollar, suffix, d)
if e == "" {
log.Fatalf("couldn't expand %q", line)
}
line = e
}
return line
}
func expnDollar(prefix, dollar, suffix string, d *data) string {
switch dollar {
case "dType":
return prefix + d.dType + suffix
@ -134,8 +154,15 @@ func expnLine(prefix, dollar, suffix string, d *data) string {
case "receiver":
return prefix + d.receiver + suffix
case "switch":
return expnSwitch("", true, suffix)
case "switchD":
return expnSwitch("", false, suffix)
case "switchS":
return expnSwitch("anyDType", false, suffix)
case "dstColorDecl":
if d.dType == "Image" {
if d.dType == "Image" || d.dType == "*image.RGBA" { // TODO: separate code for concrete types.
return "dstColorRGBA64 := &color.RGBA64{}\n" +
"dstColor := color.Color(dstColorRGBA64)"
}
@ -165,7 +192,7 @@ func expnLine(prefix, dollar, suffix string, d *data) string {
switch d.dType {
default:
log.Fatalf("bad dType %q", d.dType)
case "Image":
case "Image", "*image.RGBA": // TODO: separate code for concrete types.
return fmt.Sprintf(""+
"dstColorRGBA64.R = uint16(%sr)\n"+
"dstColorRGBA64.G = uint16(%sg)\n"+
@ -185,7 +212,7 @@ func expnLine(prefix, dollar, suffix string, d *data) string {
switch d.dType {
default:
log.Fatalf("bad dType %q", d.dType)
case "Image":
case "Image", "*image.RGBA": // TODO: separate code for concrete types.
return fmt.Sprintf(""+
"dstColorRGBA64.R = ftou(%sr * %s)\n"+
"dstColorRGBA64.G = ftou(%sg * %s)\n"+
@ -216,7 +243,7 @@ func expnLine(prefix, dollar, suffix string, d *data) string {
switch d.sType {
default:
log.Fatalf("bad sType %q", d.sType)
case "image.Image":
case "image.Image", "*image.NRGBA", "*image.RGBA", "*image.Uniform", "*image.YCbCr": // TODO: separate code for concrete types.
fmt.Fprintf(buf, "%sr%s, %sg%s, %sb%s, %sa%s := "+
"src.At(sp.X + int(%s), sp.Y+int(%s)).RGBA()\n",
lhs, tmp, lhs, tmp, lhs, tmp, lhs, tmp, args[0], args[1])
@ -240,6 +267,37 @@ func expnLine(prefix, dollar, suffix string, d *data) string {
return ""
}
func expnSwitch(dType string, expandBoth bool, template string) string {
switchVar := "dst"
if dType != "" {
switchVar = "src"
}
lines := []string{fmt.Sprintf("switch %s := %s.(type) {", switchVar, switchVar)}
fallback, values := "Image", dTypes
if dType != "" {
fallback, values = "image.Image", sTypesForDType[dType]
}
for _, v := range values {
if v == fallback {
lines = append(lines, "default:")
} else {
lines = append(lines, fmt.Sprintf("case %s:", v))
}
if dType != "" {
lines = append(lines, expnLine(template, &data{dType: dType, sType: v}))
} else if !expandBoth {
lines = append(lines, expnLine(template, &data{dType: v}))
} else {
lines = append(lines, expnSwitch(v, false, template))
}
}
lines = append(lines, "}")
return strings.Join(lines, "\n")
}
func split(s, sep string) (string, string) {
if i := strings.Index(s, sep); i >= 0 {
return strings.TrimSpace(s[:i]), strings.TrimSpace(s[i+len(sep):])
@ -289,8 +347,7 @@ const (
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
return
}
// TODO: generate type switches for the different dsTypes.
z.scale_Image_Image(dst, dp, src, sp)
$switch z.scale_$dTypeRN_$sTypeRN(dst, dp, src, sp)
}
`
@ -362,9 +419,8 @@ const (
// 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)
// TODO: generate type switches for the different dTypes and sTypes.
z.scaleX_Image(tmp, src, sp)
z.scaleY_Image(dst, dp, tmp)
$switchS z.scaleX_$sTypeRN(tmp, src, sp)
$switchD z.scaleY_$dTypeRN(dst, dp, tmp)
}
`

View File

@ -11,8 +11,111 @@ func (z *nnScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.Po
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
return
}
// TODO: generate type switches for the different dsTypes.
z.scale_Image_Image(dst, dp, src, sp)
switch dst := dst.(type) {
case *image.RGBA:
switch src := src.(type) {
case *image.NRGBA:
z.scale_RGBA_NRGBA(dst, dp, src, sp)
case *image.RGBA:
z.scale_RGBA_RGBA(dst, dp, src, sp)
case *image.Uniform:
z.scale_RGBA_Uniform(dst, dp, src, sp)
case *image.YCbCr:
z.scale_RGBA_YCbCr(dst, dp, src, sp)
default:
z.scale_RGBA_Image(dst, dp, src, sp)
}
default:
switch src := src.(type) {
default:
z.scale_Image_Image(dst, dp, src, sp)
}
}
}
func (z *nnScaler) scale_RGBA_NRGBA(dst *image.RGBA, dp image.Point, src *image.NRGBA, sp image.Point) {
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 *nnScaler) scale_RGBA_RGBA(dst *image.RGBA, dp image.Point, src *image.RGBA, sp image.Point) {
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 *nnScaler) scale_RGBA_Uniform(dst *image.RGBA, dp image.Point, src *image.Uniform, sp image.Point) {
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 *nnScaler) scale_RGBA_YCbCr(dst *image.RGBA, dp image.Point, src *image.YCbCr, sp image.Point) {
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 *nnScaler) scale_RGBA_Image(dst *image.RGBA, dp image.Point, src image.Image, sp image.Point) {
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 *nnScaler) scale_Image_Image(dst Image, dp image.Point, src image.Image, sp image.Point) {
@ -36,8 +139,386 @@ func (z *ablScaler) Scale(dst Image, dp image.Point, src image.Image, sp image.P
if z.dw <= 0 || z.dh <= 0 || z.sw <= 0 || z.sh <= 0 {
return
}
// TODO: generate type switches for the different dsTypes.
z.scale_Image_Image(dst, dp, src, sp)
switch dst := dst.(type) {
case *image.RGBA:
switch src := src.(type) {
case *image.NRGBA:
z.scale_RGBA_NRGBA(dst, dp, src, sp)
case *image.RGBA:
z.scale_RGBA_RGBA(dst, dp, src, sp)
case *image.Uniform:
z.scale_RGBA_Uniform(dst, dp, src, sp)
case *image.YCbCr:
z.scale_RGBA_YCbCr(dst, dp, src, sp)
default:
z.scale_RGBA_Image(dst, dp, src, sp)
}
default:
switch src := src.(type) {
default:
z.scale_Image_Image(dst, dp, src, sp)
}
}
}
func (z *ablScaler) scale_RGBA_NRGBA(dst *image.RGBA, dp image.Point, src *image.NRGBA, sp image.Point) {
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 *ablScaler) scale_RGBA_RGBA(dst *image.RGBA, dp image.Point, src *image.RGBA, sp image.Point) {
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 *ablScaler) scale_RGBA_Uniform(dst *image.RGBA, dp image.Point, src *image.Uniform, sp image.Point) {
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 *ablScaler) scale_RGBA_YCbCr(dst *image.RGBA, dp image.Point, src *image.YCbCr, sp image.Point) {
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 *ablScaler) scale_RGBA_Image(dst *image.RGBA, dp image.Point, src image.Image, sp image.Point) {
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 *ablScaler) scale_Image_Image(dst Image, dp image.Point, src image.Image, sp image.Point) {
@ -121,9 +602,116 @@ func (z *kernelScaler) Scale(dst Image, dp image.Point, src image.Image, sp imag
// 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)
// TODO: generate type switches for the different dTypes and sTypes.
z.scaleX_Image(tmp, src, sp)
z.scaleY_Image(dst, dp, tmp)
switch src := src.(type) {
case *image.NRGBA:
z.scaleX_NRGBA(tmp, src, sp)
case *image.RGBA:
z.scaleX_RGBA(tmp, src, sp)
case *image.Uniform:
z.scaleX_Uniform(tmp, src, sp)
case *image.YCbCr:
z.scaleX_YCbCr(tmp, src, sp)
default:
z.scaleX_Image(tmp, src, sp)
}
switch dst := dst.(type) {
case *image.RGBA:
z.scaleY_RGBA(dst, dp, tmp)
default:
z.scaleY_Image(dst, dp, tmp)
}
}
func (z *kernelScaler) scaleX_NRGBA(tmp [][4]float64, src *image.NRGBA, sp image.Point) {
t := 0
for y := int32(0); y < z.sh; y++ {
for _, s := range z.horizontal.sources {
var pr, pg, pb, pa float64
for _, c := range z.horizontal.contribs[s.i:s.j] {
pru, pgu, pbu, pau := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA()
pr += float64(pru) * c.weight
pg += float64(pgu) * c.weight
pb += float64(pbu) * c.weight
pa += float64(pau) * c.weight
}
tmp[t] = [4]float64{
pr * s.invTotalWeightFFFF,
pg * s.invTotalWeightFFFF,
pb * s.invTotalWeightFFFF,
pa * s.invTotalWeightFFFF,
}
t++
}
}
}
func (z *kernelScaler) scaleX_RGBA(tmp [][4]float64, src *image.RGBA, sp image.Point) {
t := 0
for y := int32(0); y < z.sh; y++ {
for _, s := range z.horizontal.sources {
var pr, pg, pb, pa float64
for _, c := range z.horizontal.contribs[s.i:s.j] {
pru, pgu, pbu, pau := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA()
pr += float64(pru) * c.weight
pg += float64(pgu) * c.weight
pb += float64(pbu) * c.weight
pa += float64(pau) * c.weight
}
tmp[t] = [4]float64{
pr * s.invTotalWeightFFFF,
pg * s.invTotalWeightFFFF,
pb * s.invTotalWeightFFFF,
pa * s.invTotalWeightFFFF,
}
t++
}
}
}
func (z *kernelScaler) scaleX_Uniform(tmp [][4]float64, src *image.Uniform, sp image.Point) {
t := 0
for y := int32(0); y < z.sh; y++ {
for _, s := range z.horizontal.sources {
var pr, pg, pb, pa float64
for _, c := range z.horizontal.contribs[s.i:s.j] {
pru, pgu, pbu, pau := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA()
pr += float64(pru) * c.weight
pg += float64(pgu) * c.weight
pb += float64(pbu) * c.weight
pa += float64(pau) * c.weight
}
tmp[t] = [4]float64{
pr * s.invTotalWeightFFFF,
pg * s.invTotalWeightFFFF,
pb * s.invTotalWeightFFFF,
pa * s.invTotalWeightFFFF,
}
t++
}
}
}
func (z *kernelScaler) scaleX_YCbCr(tmp [][4]float64, src *image.YCbCr, sp image.Point) {
t := 0
for y := int32(0); y < z.sh; y++ {
for _, s := range z.horizontal.sources {
var pr, pg, pb, pa float64
for _, c := range z.horizontal.contribs[s.i:s.j] {
pru, pgu, pbu, pau := src.At(sp.X+int(c.coord), sp.Y+int(y)).RGBA()
pr += float64(pru) * c.weight
pg += float64(pgu) * c.weight
pb += float64(pbu) * c.weight
pa += float64(pau) * c.weight
}
tmp[t] = [4]float64{
pr * s.invTotalWeightFFFF,
pg * s.invTotalWeightFFFF,
pb * s.invTotalWeightFFFF,
pa * s.invTotalWeightFFFF,
}
t++
}
}
}
func (z *kernelScaler) scaleX_Image(tmp [][4]float64, src image.Image, sp image.Point) {
@ -149,6 +737,28 @@ func (z *kernelScaler) scaleX_Image(tmp [][4]float64, src image.Image, sp image.
}
}
func (z *kernelScaler) scaleY_RGBA(dst *image.RGBA, 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 pr, pg, pb, pa float64
for _, c := range z.vertical.contribs[s.i:s.j] {
p := &tmp[c.coord*z.dw+x]
pr += p[0] * c.weight
pg += p[1] * c.weight
pb += p[2] * c.weight
pa += p[3] * c.weight
}
dstColorRGBA64.R = ftou(pr * s.invTotalWeight)
dstColorRGBA64.G = ftou(pg * s.invTotalWeight)
dstColorRGBA64.B = ftou(pb * s.invTotalWeight)
dstColorRGBA64.A = ftou(pa * s.invTotalWeight)
dst.Set(dp.X+int(x), dp.Y+int(y), dstColor)
}
}
}
func (z *kernelScaler) scaleY_Image(dst Image, dp image.Point, tmp [][4]float64) {
dstColorRGBA64 := &color.RGBA64{}
dstColor := color.Color(dstColorRGBA64)

View File

@ -81,26 +81,52 @@ func testScale(t *testing.T, w int, h int, direction, srcFilename string) {
func TestScaleDown(t *testing.T) { testScale(t, 100, 100, "down", "280x360.jpeg") }
func TestScaleUp(t *testing.T) { testScale(t, 75, 100, "up", "14x18.png") }
func benchScale(b *testing.B, largeSrc bool, w int, h int, q Interpolator) {
var src image.Image
if largeSrc {
// 3072 x 2304 is over 7 million pixels at 4:3, comparable to a
// 2015 smart-phone camera's output.
src = image.NewYCbCr(image.Rect(0, 0, 3072, 2304), image.YCbCrSubsampleRatio420)
} else {
// tux.png is a 386 x 395 image.
f, err := os.Open("../testdata/tux.png")
if err != nil {
b.Fatalf("Open: %v", err)
}
defer f.Close()
src, err = png.Decode(f)
if err != nil {
b.Fatalf("Decode: %v", err)
}
}
// TODO: test that scaling concrete types like *image.RGBA and *image.YCbCr
// give the same results as scaling those images wrapped in another Image or
// image.Image type that would skip the fast-path type switch.
func srcNRGBA() (image.Image, error) {
return image.NewNRGBA(image.Rect(0, 0, 1024, 768)), nil
}
func srcRGBA() (image.Image, error) {
return image.NewRGBA(image.Rect(0, 0, 1024, 768)), nil
}
func srcUniform() (image.Image, error) {
return image.White, nil
}
func srcYCbCr() (image.Image, error) {
return image.NewYCbCr(image.Rect(0, 0, 1024, 768), image.YCbCrSubsampleRatio420), nil
}
func srcYCbCrLarge() (image.Image, error) {
// 3072 x 2304 is over 7 million pixels at 4:3, comparable to a
// 2015 smart-phone camera's output.
return image.NewYCbCr(image.Rect(0, 0, 3072, 2304), image.YCbCrSubsampleRatio420), nil
}
func srcTux() (image.Image, error) {
// tux.png is a 386 x 395 image.
f, err := os.Open("../testdata/tux.png")
if err != nil {
return nil, fmt.Errorf("Open: %v", err)
}
defer f.Close()
src, err := png.Decode(f)
if err != nil {
return nil, fmt.Errorf("Decode: %v", err)
}
return src, nil
}
func benchScale(b *testing.B, srcf func() (image.Image, error), w int, h int, q Interpolator) {
dst := image.NewRGBA(image.Rect(0, 0, w, h))
src, err := srcf()
if err != nil {
b.Fatal(err)
}
dr, sr := dst.Bounds(), src.Bounds()
scaler := q.NewScaler(int32(dr.Dx()), int32(dr.Dy()), int32(sr.Dx()), int32(sr.Dy()))
@ -110,15 +136,22 @@ func benchScale(b *testing.B, largeSrc bool, w int, h int, q Interpolator) {
}
}
func BenchmarkScaleLargeDownNN(b *testing.B) { benchScale(b, true, 200, 150, NearestNeighbor) }
func BenchmarkScaleLargeDownAB(b *testing.B) { benchScale(b, true, 200, 150, ApproxBiLinear) }
func BenchmarkScaleLargeDownBL(b *testing.B) { benchScale(b, true, 200, 150, BiLinear) }
func BenchmarkScaleLargeDownCR(b *testing.B) { benchScale(b, true, 200, 150, CatmullRom) }
func BenchmarkScaleDownNN(b *testing.B) { benchScale(b, false, 120, 80, NearestNeighbor) }
func BenchmarkScaleDownAB(b *testing.B) { benchScale(b, false, 120, 80, ApproxBiLinear) }
func BenchmarkScaleDownBL(b *testing.B) { benchScale(b, false, 120, 80, BiLinear) }
func BenchmarkScaleDownCR(b *testing.B) { benchScale(b, false, 120, 80, CatmullRom) }
func BenchmarkScaleUpNN(b *testing.B) { benchScale(b, false, 800, 600, NearestNeighbor) }
func BenchmarkScaleUpAB(b *testing.B) { benchScale(b, false, 800, 600, ApproxBiLinear) }
func BenchmarkScaleUpBL(b *testing.B) { benchScale(b, false, 800, 600, BiLinear) }
func BenchmarkScaleUpCR(b *testing.B) { benchScale(b, false, 800, 600, CatmullRom) }
func BenchmarkScaleLargeDownNN(b *testing.B) { benchScale(b, srcYCbCrLarge, 200, 150, NearestNeighbor) }
func BenchmarkScaleLargeDownAB(b *testing.B) { benchScale(b, srcYCbCrLarge, 200, 150, ApproxBiLinear) }
func BenchmarkScaleLargeDownBL(b *testing.B) { benchScale(b, srcYCbCrLarge, 200, 150, BiLinear) }
func BenchmarkScaleLargeDownCR(b *testing.B) { benchScale(b, srcYCbCrLarge, 200, 150, CatmullRom) }
func BenchmarkScaleDownNN(b *testing.B) { benchScale(b, srcTux, 120, 80, NearestNeighbor) }
func BenchmarkScaleDownAB(b *testing.B) { benchScale(b, srcTux, 120, 80, ApproxBiLinear) }
func BenchmarkScaleDownBL(b *testing.B) { benchScale(b, srcTux, 120, 80, BiLinear) }
func BenchmarkScaleDownCR(b *testing.B) { benchScale(b, srcTux, 120, 80, CatmullRom) }
func BenchmarkScaleUpNN(b *testing.B) { benchScale(b, srcTux, 800, 600, NearestNeighbor) }
func BenchmarkScaleUpAB(b *testing.B) { benchScale(b, srcTux, 800, 600, ApproxBiLinear) }
func BenchmarkScaleUpBL(b *testing.B) { benchScale(b, srcTux, 800, 600, BiLinear) }
func BenchmarkScaleUpCR(b *testing.B) { benchScale(b, srcTux, 800, 600, CatmullRom) }
func BenchmarkScaleSrcNRGBA(b *testing.B) { benchScale(b, srcNRGBA, 200, 150, ApproxBiLinear) }
func BenchmarkScaleSrcRGBA(b *testing.B) { benchScale(b, srcRGBA, 200, 150, ApproxBiLinear) }
func BenchmarkScaleSrcUniform(b *testing.B) { benchScale(b, srcUniform, 200, 150, ApproxBiLinear) }
func BenchmarkScaleSrcYCbCr(b *testing.B) { benchScale(b, srcYCbCr, 200, 150, ApproxBiLinear) }