draw: add a fast path for Gray src images.
benchmark old ns/op new ns/op delta
BenchmarkScaleSrcGray 9296680 552705 -94.05%
BenchmarkTformABSrcGray 6323894 817986 -87.07%
BenchmarkTformCRSrcGray 39229583 4193194 -89.31%
Change-Id: Ie7d43dfe323d49b245b47c3206b5aad2b50cb7fb
Reviewed-on: https://go-review.googlesource.com/7711
Reviewed-by: Rob Pike <r@golang.org>
diff --git a/draw/gen.go b/draw/gen.go
index b429465..eccafee 100644
--- a/draw/gen.go
+++ b/draw/gen.go
@@ -197,7 +197,7 @@
switch d.dType {
default:
return ";"
- case "*image.RGBA":
+ case "*image.Gray", "*image.RGBA":
return "d := dst.PixOffset(dr.Min.X+adr.Min.X, dr.Min.Y+int(dy))"
}
@@ -205,7 +205,7 @@
switch d.dType {
default:
return ";"
- case "*image.RGBA":
+ case "*image.Gray", "*image.RGBA":
return "d := dst.PixOffset(dr.Min.X+int(dx), dr.Min.Y+adr.Min.Y)"
}
@@ -214,16 +214,24 @@
if len(args) != 4 {
return ""
}
- return fmt.Sprintf(""+
- "%sr = %s*%sr + %s*%sr\n"+
- "%sg = %s*%sg + %s*%sg\n"+
- "%sb = %s*%sb + %s*%sb\n"+
- "%sa = %s*%sa + %s*%sa",
- args[3], args[0], args[1], args[2], args[3],
- args[3], args[0], args[1], args[2], args[3],
- args[3], args[0], args[1], args[2], args[3],
- args[3], args[0], args[1], args[2], args[3],
- )
+ switch d.sType {
+ default:
+ return fmt.Sprintf(""+
+ "%sr = %s*%sr + %s*%sr\n"+
+ "%sg = %s*%sg + %s*%sg\n"+
+ "%sb = %s*%sb + %s*%sb\n"+
+ "%sa = %s*%sa + %s*%sa",
+ args[3], args[0], args[1], args[2], args[3],
+ args[3], args[0], args[1], args[2], args[3],
+ args[3], args[0], args[1], args[2], args[3],
+ args[3], args[0], args[1], args[2], args[3],
+ )
+ case "*image.Gray":
+ return fmt.Sprintf(""+
+ "%sr = %s*%sr + %s*%sr",
+ args[3], args[0], args[1], args[2], args[3],
+ )
+ }
case "outputu":
args, _ := splitArgs(suffix)
@@ -234,23 +242,49 @@
default:
log.Fatalf("bad dType %q", d.dType)
case "Image":
- return fmt.Sprintf(""+
- "dstColorRGBA64.R = uint16(%sr)\n"+
- "dstColorRGBA64.G = uint16(%sg)\n"+
- "dstColorRGBA64.B = uint16(%sb)\n"+
- "dstColorRGBA64.A = uint16(%sa)\n"+
- "dst.Set(%s, %s, dstColor)",
- args[2], args[2], args[2], args[2],
- args[0], args[1],
- )
+ switch d.sType {
+ default:
+ return fmt.Sprintf(""+
+ "dstColorRGBA64.R = uint16(%sr)\n"+
+ "dstColorRGBA64.G = uint16(%sg)\n"+
+ "dstColorRGBA64.B = uint16(%sb)\n"+
+ "dstColorRGBA64.A = uint16(%sa)\n"+
+ "dst.Set(%s, %s, dstColor)",
+ args[2], args[2], args[2], args[2],
+ args[0], args[1],
+ )
+ case "*image.Gray":
+ return fmt.Sprintf(""+
+ "out := uint16(%sr)\n"+
+ "dstColorRGBA64.R = out\n"+
+ "dstColorRGBA64.G = out\n"+
+ "dstColorRGBA64.B = out\n"+
+ "dstColorRGBA64.A = 0xffff\n"+
+ "dst.Set(%s, %s, dstColor)",
+ args[2],
+ args[0], args[1],
+ )
+ }
case "*image.RGBA":
- return fmt.Sprintf(""+
- "dst.Pix[d+0] = uint8(uint32(%sr) >> 8)\n"+
- "dst.Pix[d+1] = uint8(uint32(%sg) >> 8)\n"+
- "dst.Pix[d+2] = uint8(uint32(%sb) >> 8)\n"+
- "dst.Pix[d+3] = uint8(uint32(%sa) >> 8)",
- args[2], args[2], args[2], args[2],
- )
+ switch d.sType {
+ default:
+ return fmt.Sprintf(""+
+ "dst.Pix[d+0] = uint8(uint32(%sr) >> 8)\n"+
+ "dst.Pix[d+1] = uint8(uint32(%sg) >> 8)\n"+
+ "dst.Pix[d+2] = uint8(uint32(%sb) >> 8)\n"+
+ "dst.Pix[d+3] = uint8(uint32(%sa) >> 8)",
+ args[2], args[2], args[2], args[2],
+ )
+ case "*image.Gray":
+ return fmt.Sprintf(""+
+ "out := uint8(uint32(%sr) >> 8)\n"+
+ "dst.Pix[d+0] = out\n"+
+ "dst.Pix[d+1] = out\n"+
+ "dst.Pix[d+2] = out\n"+
+ "dst.Pix[d+3] = 0xff",
+ args[2],
+ )
+ }
}
case "outputf":
@@ -263,29 +297,55 @@
default:
log.Fatalf("bad dType %q", d.dType)
case "Image":
- ret = fmt.Sprintf(""+
- "dstColorRGBA64.R = %s(%sr * %s)\n"+
- "dstColorRGBA64.G = %s(%sg * %s)\n"+
- "dstColorRGBA64.B = %s(%sb * %s)\n"+
- "dstColorRGBA64.A = %s(%sa * %s)\n"+
- "dst.Set(%s, %s, dstColor)",
- args[2], args[3], args[4],
- args[2], args[3], args[4],
- args[2], args[3], args[4],
- args[2], args[3], args[4],
- args[0], args[1],
- )
+ switch d.sType {
+ default:
+ ret = fmt.Sprintf(""+
+ "dstColorRGBA64.R = %s(%sr * %s)\n"+
+ "dstColorRGBA64.G = %s(%sg * %s)\n"+
+ "dstColorRGBA64.B = %s(%sb * %s)\n"+
+ "dstColorRGBA64.A = %s(%sa * %s)\n"+
+ "dst.Set(%s, %s, dstColor)",
+ args[2], args[3], args[4],
+ args[2], args[3], args[4],
+ args[2], args[3], args[4],
+ args[2], args[3], args[4],
+ args[0], args[1],
+ )
+ case "*image.Gray":
+ ret = fmt.Sprintf(""+
+ "out := %s(%sr * %s)\n"+
+ "dstColorRGBA64.R = out\n"+
+ "dstColorRGBA64.G = out\n"+
+ "dstColorRGBA64.B = out\n"+
+ "dstColorRGBA64.A = 0xffff\n"+
+ "dst.Set(%s, %s, dstColor)",
+ args[2], args[3], args[4],
+ args[0], args[1],
+ )
+ }
case "*image.RGBA":
- ret = fmt.Sprintf(""+
- "dst.Pix[d+0] = uint8(%s(%sr * %s) >> 8)\n"+
- "dst.Pix[d+1] = uint8(%s(%sg * %s) >> 8)\n"+
- "dst.Pix[d+2] = uint8(%s(%sb * %s) >> 8)\n"+
- "dst.Pix[d+3] = uint8(%s(%sa * %s) >> 8)",
- args[2], args[3], args[4],
- args[2], args[3], args[4],
- args[2], args[3], args[4],
- args[2], args[3], args[4],
- )
+ switch d.sType {
+ default:
+ ret = fmt.Sprintf(""+
+ "dst.Pix[d+0] = uint8(%s(%sr * %s) >> 8)\n"+
+ "dst.Pix[d+1] = uint8(%s(%sg * %s) >> 8)\n"+
+ "dst.Pix[d+2] = uint8(%s(%sb * %s) >> 8)\n"+
+ "dst.Pix[d+3] = uint8(%s(%sa * %s) >> 8)",
+ args[2], args[3], args[4],
+ args[2], args[3], args[4],
+ args[2], args[3], args[4],
+ args[2], args[3], args[4],
+ )
+ case "*image.Gray":
+ ret = fmt.Sprintf(""+
+ "out := uint8(%s(%sr * %s) >> 8)\n"+
+ "dst.Pix[d+0] = out\n"+
+ "dst.Pix[d+1] = out\n"+
+ "dst.Pix[d+2] = out\n"+
+ "dst.Pix[d+3] = 0xff",
+ args[2], args[3], args[4],
+ )
+ }
}
return strings.Replace(ret, " * 1)", ")", -1)
@@ -308,12 +368,20 @@
switch d.sType {
default:
log.Fatalf("bad sType %q", d.sType)
- case "image.Image", "*image.Gray", "*image.NRGBA", "*image.Uniform", "*image.YCbCr": // TODO: separate code for concrete types.
+ case "image.Image", "*image.NRGBA", "*image.Uniform", "*image.YCbCr": // TODO: separate code for concrete types.
fmt.Fprintf(buf, "%sr%s, %sg%s, %sb%s, %sa%s := "+
"src.At(%s, %s).RGBA()\n",
lhs, tmp, lhs, tmp, lhs, tmp, lhs, tmp,
args[0], args[1],
)
+ case "*image.Gray":
+ // TODO: there's no need to multiply by 0x101 if the next thing
+ // we're going to do is shift right by 8.
+ fmt.Fprintf(buf, "%si := src.PixOffset(%s, %s)\n"+
+ "%sr%s := uint32(src.Pix[%si]) * 0x101\n",
+ lhs, args[0], args[1],
+ lhs, tmp, lhs,
+ )
case "*image.RGBA":
// TODO: there's no need to multiply by 0x101 if the next thing
// we're going to do is shift right by 8.
@@ -331,16 +399,24 @@
}
if dollar == "srcf" {
- fmt.Fprintf(buf, ""+
- "%sr %s float64(%sru)%s\n"+
- "%sg %s float64(%sgu)%s\n"+
- "%sb %s float64(%sbu)%s\n"+
- "%sa %s float64(%sau)%s\n",
- lhs, eqOp, lhs, extra,
- lhs, eqOp, lhs, extra,
- lhs, eqOp, lhs, extra,
- lhs, eqOp, lhs, extra,
- )
+ switch d.sType {
+ default:
+ fmt.Fprintf(buf, ""+
+ "%sr %s float64(%sru)%s\n"+
+ "%sg %s float64(%sgu)%s\n"+
+ "%sb %s float64(%sbu)%s\n"+
+ "%sa %s float64(%sau)%s\n",
+ lhs, eqOp, lhs, extra,
+ lhs, eqOp, lhs, extra,
+ lhs, eqOp, lhs, extra,
+ lhs, eqOp, lhs, extra,
+ )
+ case "*image.Gray":
+ fmt.Fprintf(buf, ""+
+ "%sr %s float64(%sru)%s\n",
+ lhs, eqOp, lhs, extra,
+ )
+ }
}
return strings.TrimSpace(buf.String())
@@ -362,6 +438,27 @@
return strings.Replace(suffix, "for dy, s", "for _, s", 1)
}
return suffix
+
+ case "tweakP":
+ if d.sType == "*image.Gray" {
+ if strings.HasPrefix(strings.TrimSpace(suffix), "pa * ") {
+ return "1,"
+ }
+ return "pr,"
+ }
+ return suffix
+
+ case "tweakPr":
+ if d.sType == "*image.Gray" {
+ return "pr *= s.invTotalWeightFFFF"
+ }
+ return ";"
+
+ case "tweakVarP":
+ if d.sType == "*image.Gray" {
+ return strings.Replace(suffix, "var pr, pg, pb, pa", "var pr", 1)
+ }
+ return suffix
}
return ""
}
@@ -690,15 +787,16 @@
t := 0
for y := int32(0); y < z.sh; y++ {
for _, s := range z.horizontal.sources {
- var pr, pg, pb, pa float64
+ $tweakVarP var pr, pg, pb, pa float64
for _, c := range z.horizontal.contribs[s.i:s.j] {
p += $srcf[sr.Min.X + int(c.coord), sr.Min.Y + int(y)] * c.weight
}
+ $tweakPr
tmp[t] = [4]float64{
- pr * s.invTotalWeightFFFF,
- pg * s.invTotalWeightFFFF,
- pb * s.invTotalWeightFFFF,
- pa * s.invTotalWeightFFFF,
+ $tweakP pr * s.invTotalWeightFFFF,
+ $tweakP pg * s.invTotalWeightFFFF,
+ $tweakP pb * s.invTotalWeightFFFF,
+ $tweakP pa * s.invTotalWeightFFFF,
}
t++
}
@@ -804,7 +902,7 @@
yWeights[y] /= totalYWeight
}
- var pr, pg, pb, pa float64
+ $tweakVarP var pr, pg, pb, pa float64
for ky := iy; ky < jy; ky++ {
yWeight := yWeights[ky - iy]
for kx := ix; kx < jx; kx++ {
diff --git a/draw/impl.go b/draw/impl.go
index 8ebdd6f..cc0ed77 100644
--- a/draw/impl.go
+++ b/draw/impl.go
@@ -96,11 +96,13 @@
d := dst.PixOffset(dr.Min.X+adr.Min.X, dr.Min.Y+int(dy))
for dx := int32(adr.Min.X); dx < int32(adr.Max.X); dx, d = dx+1, d+4 {
sx := (2*uint64(dx) + 1) * sw / dw2
- pr, pg, pb, pa := src.At(sr.Min.X+int(sx), sr.Min.Y+int(sy)).RGBA()
- dst.Pix[d+0] = uint8(uint32(pr) >> 8)
- dst.Pix[d+1] = uint8(uint32(pg) >> 8)
- dst.Pix[d+2] = uint8(uint32(pb) >> 8)
- dst.Pix[d+3] = uint8(uint32(pa) >> 8)
+ pi := src.PixOffset(sr.Min.X+int(sx), sr.Min.Y+int(sy))
+ pr := uint32(src.Pix[pi]) * 0x101
+ out := uint8(uint32(pr) >> 8)
+ dst.Pix[d+0] = out
+ dst.Pix[d+1] = out
+ dst.Pix[d+2] = out
+ dst.Pix[d+3] = 0xff
}
}
}
@@ -237,11 +239,13 @@
if !(image.Point{sx0, sy0}).In(sr) {
continue
}
- pr, pg, pb, pa := src.At(sx0, sy0).RGBA()
- dst.Pix[d+0] = uint8(uint32(pr) >> 8)
- dst.Pix[d+1] = uint8(uint32(pg) >> 8)
- dst.Pix[d+2] = uint8(uint32(pb) >> 8)
- dst.Pix[d+3] = uint8(uint32(pa) >> 8)
+ pi := src.PixOffset(sx0, sy0)
+ pr := uint32(src.Pix[pi]) * 0x101
+ out := uint8(uint32(pr) >> 8)
+ dst.Pix[d+0] = out
+ dst.Pix[d+1] = out
+ dst.Pix[d+2] = out
+ dst.Pix[d+3] = 0xff
}
}
}
@@ -493,42 +497,26 @@
xFrac0, xFrac1 = 1, 0
}
- s00ru, s00gu, s00bu, s00au := src.At(sr.Min.X+int(sx0), sr.Min.Y+int(sy0)).RGBA()
+ s00i := src.PixOffset(sr.Min.X+int(sx0), sr.Min.Y+int(sy0))
+ s00ru := uint32(src.Pix[s00i]) * 0x101
s00r := float64(s00ru)
- s00g := float64(s00gu)
- s00b := float64(s00bu)
- s00a := float64(s00au)
- s10ru, s10gu, s10bu, s10au := src.At(sr.Min.X+int(sx1), sr.Min.Y+int(sy0)).RGBA()
+ s10i := src.PixOffset(sr.Min.X+int(sx1), sr.Min.Y+int(sy0))
+ s10ru := uint32(src.Pix[s10i]) * 0x101
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(sr.Min.X+int(sx0), sr.Min.Y+int(sy1)).RGBA()
+ s01i := src.PixOffset(sr.Min.X+int(sx0), sr.Min.Y+int(sy1))
+ s01ru := uint32(src.Pix[s01i]) * 0x101
s01r := float64(s01ru)
- s01g := float64(s01gu)
- s01b := float64(s01bu)
- s01a := float64(s01au)
- s11ru, s11gu, s11bu, s11au := src.At(sr.Min.X+int(sx1), sr.Min.Y+int(sy1)).RGBA()
+ s11i := src.PixOffset(sr.Min.X+int(sx1), sr.Min.Y+int(sy1))
+ s11ru := uint32(src.Pix[s11i]) * 0x101
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
- dst.Pix[d+0] = uint8(uint32(s11r) >> 8)
- dst.Pix[d+1] = uint8(uint32(s11g) >> 8)
- dst.Pix[d+2] = uint8(uint32(s11b) >> 8)
- dst.Pix[d+3] = uint8(uint32(s11a) >> 8)
+ out := uint8(uint32(s11r) >> 8)
+ dst.Pix[d+0] = out
+ dst.Pix[d+1] = out
+ dst.Pix[d+2] = out
+ dst.Pix[d+3] = 0xff
}
}
}
@@ -1066,42 +1054,26 @@
yFrac0, yFrac1 = 1, 0
}
- s00ru, s00gu, s00bu, s00au := src.At(sx0, sy0).RGBA()
+ s00i := src.PixOffset(sx0, sy0)
+ s00ru := uint32(src.Pix[s00i]) * 0x101
s00r := float64(s00ru)
- s00g := float64(s00gu)
- s00b := float64(s00bu)
- s00a := float64(s00au)
- s10ru, s10gu, s10bu, s10au := src.At(sx1, sy0).RGBA()
+ s10i := src.PixOffset(sx1, sy0)
+ s10ru := uint32(src.Pix[s10i]) * 0x101
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(sx0, sy1).RGBA()
+ s01i := src.PixOffset(sx0, sy1)
+ s01ru := uint32(src.Pix[s01i]) * 0x101
s01r := float64(s01ru)
- s01g := float64(s01gu)
- s01b := float64(s01bu)
- s01a := float64(s01au)
- s11ru, s11gu, s11bu, s11au := src.At(sx1, sy1).RGBA()
+ s11i := src.PixOffset(sx1, sy1)
+ s11ru := uint32(src.Pix[s11i]) * 0x101
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
- dst.Pix[d+0] = uint8(uint32(s11r) >> 8)
- dst.Pix[d+1] = uint8(uint32(s11g) >> 8)
- dst.Pix[d+2] = uint8(uint32(s11b) >> 8)
- dst.Pix[d+3] = uint8(uint32(s11a) >> 8)
+ out := uint8(uint32(s11r) >> 8)
+ dst.Pix[d+0] = out
+ dst.Pix[d+1] = out
+ dst.Pix[d+2] = out
+ dst.Pix[d+3] = 0xff
}
}
}
@@ -1709,19 +1681,18 @@
t := 0
for y := int32(0); y < z.sh; y++ {
for _, s := range z.horizontal.sources {
- var pr, pg, pb, pa float64
+ var pr float64
for _, c := range z.horizontal.contribs[s.i:s.j] {
- pru, pgu, pbu, pau := src.At(sr.Min.X+int(c.coord), sr.Min.Y+int(y)).RGBA()
+ pi := src.PixOffset(sr.Min.X+int(c.coord), sr.Min.Y+int(y))
+ pru := uint32(src.Pix[pi]) * 0x101
pr += float64(pru) * c.weight
- pg += float64(pgu) * c.weight
- pb += float64(pbu) * c.weight
- pa += float64(pau) * c.weight
}
+ pr *= s.invTotalWeightFFFF
tmp[t] = [4]float64{
- pr * s.invTotalWeightFFFF,
- pg * s.invTotalWeightFFFF,
- pb * s.invTotalWeightFFFF,
- pa * s.invTotalWeightFFFF,
+ pr,
+ pr,
+ pr,
+ 1,
}
t++
}
@@ -1965,21 +1936,20 @@
yWeights[y] /= totalYWeight
}
- var pr, pg, pb, pa float64
+ var pr float64
for ky := iy; ky < jy; ky++ {
yWeight := yWeights[ky-iy]
for kx := ix; kx < jx; kx++ {
- pru, pgu, pbu, pau := src.At(kx, ky).RGBA()
+ pi := src.PixOffset(kx, ky)
+ pru := uint32(src.Pix[pi]) * 0x101
pr += float64(pru) * xWeights[kx-ix] * yWeight
- pg += float64(pgu) * xWeights[kx-ix] * yWeight
- pb += float64(pbu) * xWeights[kx-ix] * yWeight
- pa += float64(pau) * xWeights[kx-ix] * yWeight
}
}
- dst.Pix[d+0] = uint8(fffftou(pr) >> 8)
- dst.Pix[d+1] = uint8(fffftou(pg) >> 8)
- dst.Pix[d+2] = uint8(fffftou(pb) >> 8)
- dst.Pix[d+3] = uint8(fffftou(pa) >> 8)
+ out := uint8(fffftou(pr) >> 8)
+ dst.Pix[d+0] = out
+ dst.Pix[d+1] = out
+ dst.Pix[d+2] = out
+ dst.Pix[d+3] = 0xff
}
}
}
