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mirror of https://github.com/golang/go synced 2024-11-21 23:34:42 -07:00

image: change image representation from slice-of-slices to linear buffer,

stride and rect.

R=r
CC=golang-dev, rog
https://golang.org/cl/1849041
This commit is contained in:
Nigel Tao 2010-08-10 16:34:57 +10:00
parent 56b989f1b9
commit b50a3d95e1
5 changed files with 301 additions and 236 deletions

View File

@ -167,14 +167,14 @@ func drawFillOver(dst *image.RGBA, r Rectangle, src image.ColorImage) {
x0, x1 := r.Min.X, r.Max.X
y0, y1 := r.Min.Y, r.Max.Y
for y := y0; y != y1; y++ {
dpix := dst.Pixel[y]
for x := x0; x != x1; x++ {
rgba := dpix[x]
dbase := y * dst.Stride
dpix := dst.Pix[dbase+x0 : dbase+x1]
for i, rgba := range dpix {
dr := (uint32(rgba.R)*a)/m + cr
dg := (uint32(rgba.G)*a)/m + cg
db := (uint32(rgba.B)*a)/m + cb
da := (uint32(rgba.A)*a)/m + ca
dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
}
}
}
@ -183,25 +183,26 @@ func drawCopyOver(dst *image.RGBA, r Rectangle, src *image.RGBA, sp Point) {
x0, x1 := r.Min.X, r.Max.X
y0, y1 := r.Min.Y, r.Max.Y
for y, sy := y0, sp.Y; y != y1; y, sy = y+1, sy+1 {
dpix := dst.Pixel[y]
spix := src.Pixel[sy]
for x, sx := x0, sp.X; x != x1; x, sx = x+1, sx+1 {
// For unknown reasons, even though both dpix[x] and spix[sx] are
dbase := y * dst.Stride
dpix := dst.Pix[dbase+x0 : dbase+x1]
sbase := sy * src.Stride
spix := src.Pix[sbase+sp.X:]
for i, rgba := range dpix {
// For unknown reasons, even though both dpix[i] and spix[i] are
// image.RGBAColors, on an x86 CPU it seems fastest to call RGBA
// for the source but to do it manually for the destination.
sr, sg, sb, sa := spix[sx].RGBA()
drgba := dpix[x]
dr := uint32(drgba.R)
dg := uint32(drgba.G)
db := uint32(drgba.B)
da := uint32(drgba.A)
sr, sg, sb, sa := spix[i].RGBA()
dr := uint32(rgba.R)
dg := uint32(rgba.G)
db := uint32(rgba.B)
da := uint32(rgba.A)
// The 0x101 is here for the same reason as in drawRGBA.
a := (m - sa) * 0x101
dr = (dr*a)/m + sr
dg = (dg*a)/m + sg
db = (db*a)/m + sb
da = (da*a)/m + sa
dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
}
}
}
@ -211,15 +212,16 @@ func drawGlyphOver(dst *image.RGBA, r Rectangle, src image.ColorImage, mask *ima
y0, y1 := r.Min.Y, r.Max.Y
cr, cg, cb, ca := src.RGBA()
for y, my := y0, mp.Y; y != y1; y, my = y+1, my+1 {
dpix := dst.Pixel[y]
mpix := mask.Pixel[my]
for x, mx := x0, mp.X; x != x1; x, mx = x+1, mx+1 {
ma := uint32(mpix[mx].A)
dbase := y * dst.Stride
dpix := dst.Pix[dbase+x0 : dbase+x1]
mbase := my * mask.Stride
mpix := mask.Pix[mbase+mp.X:]
for i, rgba := range dpix {
ma := uint32(mpix[i].A)
if ma == 0 {
continue
}
ma |= ma << 8
rgba := dpix[x]
dr := uint32(rgba.R)
dg := uint32(rgba.G)
db := uint32(rgba.B)
@ -230,7 +232,7 @@ func drawGlyphOver(dst *image.RGBA, r Rectangle, src image.ColorImage, mask *ima
dg = (dg*a + cg*ma) / m
db = (db*a + cb*ma) / m
da = (da*a + ca*ma) / m
dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
}
}
}
@ -246,13 +248,16 @@ func drawFillSrc(dst *image.RGBA, r Rectangle, src image.ColorImage) {
// then use the first row as the slice source for the remaining rows.
dx0, dx1 := r.Min.X, r.Max.X
dy0, dy1 := r.Min.Y, r.Max.Y
firstRow := dst.Pixel[dy0]
for x := dx0; x < dx1; x++ {
firstRow[x] = color
dbase := dy0 * dst.Stride
i0, i1 := dbase+dx0, dbase+dx1
firstRow := dst.Pix[i0:i1]
for i, _ := range firstRow {
firstRow[i] = color
}
copySrc := firstRow[dx0:dx1]
for y := dy0 + 1; y < dy1; y++ {
copy(dst.Pixel[y][dx0:dx1], copySrc)
i0 += dst.Stride
i1 += dst.Stride
copy(dst.Pix[i0:i1], firstRow)
}
}
@ -260,8 +265,16 @@ func drawCopySrc(dst *image.RGBA, r Rectangle, src *image.RGBA, sp Point) {
dx0, dx1 := r.Min.X, r.Max.X
dy0, dy1 := r.Min.Y, r.Max.Y
sx0, sx1 := sp.X, sp.X+dx1-dx0
for y, sy := dy0, sp.Y; y < dy1; y, sy = y+1, sy+1 {
copy(dst.Pixel[y][dx0:dx1], src.Pixel[sy][sx0:sx1])
d0 := dy0*dst.Stride + dx0
d1 := dy0*dst.Stride + dx1
s0 := sp.Y*dst.Stride + sx0
s1 := sp.Y*dst.Stride + sx1
for y := dy0; y < dy1; y++ {
copy(dst.Pix[d0:d1], src.Pix[s0:s1])
d0 += dst.Stride
d1 += dst.Stride
s0 += src.Stride
s1 += src.Stride
}
}
@ -280,8 +293,9 @@ func drawRGBA(dst *image.RGBA, r Rectangle, src image.Image, sp Point, mask imag
for y := y0; y != y1; y, sy, my = y+dy, sy+dy, my+dy {
sx := sp.X + x0 - r.Min.X
mx := mp.X + x0 - r.Min.X
dpix := dst.Pixel[y]
for x := x0; x != x1; x, sx, mx = x+dx, sx+dx, mx+dx {
dbase := y * dst.Stride
dpix := dst.Pix[dbase+x0 : dbase+x1]
for i, rgba := range dpix {
ma := uint32(m)
if mask != nil {
_, _, _, ma = mask.At(mx, my).RGBA()
@ -289,7 +303,6 @@ func drawRGBA(dst *image.RGBA, r Rectangle, src image.Image, sp Point, mask imag
sr, sg, sb, sa := src.At(sx, sy).RGBA()
var dr, dg, db, da uint32
if op == Over {
rgba := dpix[x]
dr = uint32(rgba.R)
dg = uint32(rgba.G)
db = uint32(rgba.B)
@ -311,7 +324,8 @@ func drawRGBA(dst *image.RGBA, r Rectangle, src image.Image, sp Point, mask imag
db = sb * ma / m
da = sa * ma / m
}
dpix[x] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
dpix[i] = image.RGBAColor{uint8(dr >> 8), uint8(dg >> 8), uint8(db >> 8), uint8(da >> 8)}
sx, mx = sx+dx, mx+dx
}
}
}

View File

@ -99,7 +99,7 @@ func (c *conn) flusher() {
close(c.flush)
return
}
p := c.img.Pixel[y]
p := c.img.Pix[y*c.img.Stride : (y+1)*c.img.Stride]
for x := b.Min.X; x < b.Max.X; {
nx := b.Max.X - x
if nx > len(c.flushBuf1)/4 {

View File

@ -97,6 +97,12 @@ func (r Rectangle) Overlaps(s Rectangle) bool {
r.Min.Y < s.Max.Y && s.Min.Y < r.Max.Y
}
// Contains returns whether r contains p.
func (r Rectangle) Contains(p Point) bool {
return p.X >= r.Min.X && p.X < r.Max.X &&
p.Y >= r.Min.Y && p.Y < r.Max.Y
}
// Canon returns the canonical version of r. The returned rectangle has
// minimum and maximum coordinates swapped if necessary so that Min.X <= Max.X
// and Min.Y <= Max.Y.

View File

@ -18,46 +18,48 @@ type Image interface {
At(x, y int) Color
}
// An RGBA is an in-memory image backed by a 2-D slice of RGBAColor values.
// An RGBA is an in-memory image of RGBAColor values.
type RGBA struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]RGBAColor
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []RGBAColor
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *RGBA) ColorModel() ColorModel { return RGBAColorModel }
func (p *RGBA) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
}
func (p *RGBA) Bounds() Rectangle { return p.Rect }
func (p *RGBA) At(x, y int) Color {
// TODO(nigeltao): Check if (x,y) is outside the bounds, and return zero.
// Similarly for the other concrete image types.
return p.Pixel[y][x]
if !p.Rect.Contains(Point{x, y}) {
return RGBAColor{}
}
return p.Pix[y*p.Stride+x]
}
func (p *RGBA) Set(x, y int, c Color) {
// TODO(nigeltao): Check if (x,y) is outside the bounds, and return.
// Similarly for the other concrete image types.
p.Pixel[y][x] = toRGBAColor(c).(RGBAColor)
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toRGBAColor(c).(RGBAColor)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *RGBA) Opaque() bool {
h := len(p.Pixel)
if h > 0 {
w := len(p.Pixel[0])
for y := 0; y < h; y++ {
pix := p.Pixel[y]
for x := 0; x < w; x++ {
if pix[x].A != 0xff {
return false
}
if p.Rect.Empty() {
return true
}
base := p.Rect.Min.Y * p.Stride
i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
for _, c := range p.Pix[i0:i1] {
if c.A != 0xff {
return false
}
}
i0 += p.Stride
i1 += p.Stride
}
return true
}
@ -65,261 +67,295 @@ func (p *RGBA) Opaque() bool {
// NewRGBA returns a new RGBA with the given width and height.
func NewRGBA(w, h int) *RGBA {
buf := make([]RGBAColor, w*h)
pix := make([][]RGBAColor, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &RGBA{pix}
return &RGBA{buf, w, Rectangle{ZP, Point{w, h}}}
}
// An RGBA64 is an in-memory image backed by a 2-D slice of RGBA64Color values.
// An RGBA64 is an in-memory image of RGBA64Color values.
type RGBA64 struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]RGBA64Color
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []RGBA64Color
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *RGBA64) ColorModel() ColorModel { return RGBA64ColorModel }
func (p *RGBA64) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *RGBA64) Bounds() Rectangle { return p.Rect }
func (p *RGBA64) At(x, y int) Color {
if !p.Rect.Contains(Point{x, y}) {
return RGBA64Color{}
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
return p.Pix[y*p.Stride+x]
}
func (p *RGBA64) At(x, y int) Color { return p.Pixel[y][x] }
func (p *RGBA64) Set(x, y int, c Color) { p.Pixel[y][x] = toRGBA64Color(c).(RGBA64Color) }
func (p *RGBA64) Set(x, y int, c Color) {
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toRGBA64Color(c).(RGBA64Color)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *RGBA64) Opaque() bool {
h := len(p.Pixel)
if h > 0 {
w := len(p.Pixel[0])
for y := 0; y < h; y++ {
pix := p.Pixel[y]
for x := 0; x < w; x++ {
if pix[x].A != 0xffff {
return false
}
if p.Rect.Empty() {
return true
}
base := p.Rect.Min.Y * p.Stride
i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
for _, c := range p.Pix[i0:i1] {
if c.A != 0xffff {
return false
}
}
i0 += p.Stride
i1 += p.Stride
}
return true
}
// NewRGBA64 returns a new RGBA64 with the given width and height.
func NewRGBA64(w, h int) *RGBA64 {
buf := make([]RGBA64Color, w*h)
pix := make([][]RGBA64Color, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &RGBA64{pix}
pix := make([]RGBA64Color, w*h)
return &RGBA64{pix, w, Rectangle{ZP, Point{w, h}}}
}
// A NRGBA is an in-memory image backed by a 2-D slice of NRGBAColor values.
// An NRGBA is an in-memory image of NRGBAColor values.
type NRGBA struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]NRGBAColor
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []NRGBAColor
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *NRGBA) ColorModel() ColorModel { return NRGBAColorModel }
func (p *NRGBA) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *NRGBA) Bounds() Rectangle { return p.Rect }
func (p *NRGBA) At(x, y int) Color {
if !p.Rect.Contains(Point{x, y}) {
return NRGBAColor{}
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
return p.Pix[y*p.Stride+x]
}
func (p *NRGBA) At(x, y int) Color { return p.Pixel[y][x] }
func (p *NRGBA) Set(x, y int, c Color) { p.Pixel[y][x] = toNRGBAColor(c).(NRGBAColor) }
func (p *NRGBA) Set(x, y int, c Color) {
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toNRGBAColor(c).(NRGBAColor)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *NRGBA) Opaque() bool {
h := len(p.Pixel)
if h > 0 {
w := len(p.Pixel[0])
for y := 0; y < h; y++ {
pix := p.Pixel[y]
for x := 0; x < w; x++ {
if pix[x].A != 0xff {
return false
}
if p.Rect.Empty() {
return true
}
base := p.Rect.Min.Y * p.Stride
i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
for _, c := range p.Pix[i0:i1] {
if c.A != 0xff {
return false
}
}
i0 += p.Stride
i1 += p.Stride
}
return true
}
// NewNRGBA returns a new NRGBA with the given width and height.
func NewNRGBA(w, h int) *NRGBA {
buf := make([]NRGBAColor, w*h)
pix := make([][]NRGBAColor, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &NRGBA{pix}
pix := make([]NRGBAColor, w*h)
return &NRGBA{pix, w, Rectangle{ZP, Point{w, h}}}
}
// A NRGBA64 is an in-memory image backed by a 2-D slice of NRGBA64Color values.
// An NRGBA64 is an in-memory image of NRGBA64Color values.
type NRGBA64 struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]NRGBA64Color
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []NRGBA64Color
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *NRGBA64) ColorModel() ColorModel { return NRGBA64ColorModel }
func (p *NRGBA64) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *NRGBA64) Bounds() Rectangle { return p.Rect }
func (p *NRGBA64) At(x, y int) Color {
if !p.Rect.Contains(Point{x, y}) {
return NRGBA64Color{}
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
return p.Pix[y*p.Stride+x]
}
func (p *NRGBA64) At(x, y int) Color { return p.Pixel[y][x] }
func (p *NRGBA64) Set(x, y int, c Color) { p.Pixel[y][x] = toNRGBA64Color(c).(NRGBA64Color) }
func (p *NRGBA64) Set(x, y int, c Color) {
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toNRGBA64Color(c).(NRGBA64Color)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *NRGBA64) Opaque() bool {
h := len(p.Pixel)
if h > 0 {
w := len(p.Pixel[0])
for y := 0; y < h; y++ {
pix := p.Pixel[y]
for x := 0; x < w; x++ {
if pix[x].A != 0xffff {
return false
}
if p.Rect.Empty() {
return true
}
base := p.Rect.Min.Y * p.Stride
i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
for _, c := range p.Pix[i0:i1] {
if c.A != 0xffff {
return false
}
}
i0 += p.Stride
i1 += p.Stride
}
return true
}
// NewNRGBA64 returns a new NRGBA64 with the given width and height.
func NewNRGBA64(w, h int) *NRGBA64 {
buf := make([]NRGBA64Color, w*h)
pix := make([][]NRGBA64Color, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &NRGBA64{pix}
pix := make([]NRGBA64Color, w*h)
return &NRGBA64{pix, w, Rectangle{ZP, Point{w, h}}}
}
// An Alpha is an in-memory image backed by a 2-D slice of AlphaColor values.
// An Alpha is an in-memory image of AlphaColor values.
type Alpha struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]AlphaColor
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []AlphaColor
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *Alpha) ColorModel() ColorModel { return AlphaColorModel }
func (p *Alpha) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *Alpha) Bounds() Rectangle { return p.Rect }
func (p *Alpha) At(x, y int) Color {
if !p.Rect.Contains(Point{x, y}) {
return AlphaColor{}
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
return p.Pix[y*p.Stride+x]
}
func (p *Alpha) At(x, y int) Color { return p.Pixel[y][x] }
func (p *Alpha) Set(x, y int, c Color) { p.Pixel[y][x] = toAlphaColor(c).(AlphaColor) }
func (p *Alpha) Set(x, y int, c Color) {
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toAlphaColor(c).(AlphaColor)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Alpha) Opaque() bool {
h := len(p.Pixel)
if h > 0 {
w := len(p.Pixel[0])
for y := 0; y < h; y++ {
pix := p.Pixel[y]
for x := 0; x < w; x++ {
if pix[x].A != 0xff {
return false
}
if p.Rect.Empty() {
return true
}
base := p.Rect.Min.Y * p.Stride
i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
for _, c := range p.Pix[i0:i1] {
if c.A != 0xff {
return false
}
}
i0 += p.Stride
i1 += p.Stride
}
return true
}
// NewAlpha returns a new Alpha with the given width and height.
func NewAlpha(w, h int) *Alpha {
buf := make([]AlphaColor, w*h)
pix := make([][]AlphaColor, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &Alpha{pix}
pix := make([]AlphaColor, w*h)
return &Alpha{pix, w, Rectangle{ZP, Point{w, h}}}
}
// An Alpha16 is an in-memory image backed by a 2-D slice of Alpha16Color values.
// An Alpha16 is an in-memory image of Alpha16Color values.
type Alpha16 struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]Alpha16Color
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []Alpha16Color
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *Alpha16) ColorModel() ColorModel { return Alpha16ColorModel }
func (p *Alpha16) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *Alpha16) Bounds() Rectangle { return p.Rect }
func (p *Alpha16) At(x, y int) Color {
if !p.Rect.Contains(Point{x, y}) {
return Alpha16Color{}
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
return p.Pix[y*p.Stride+x]
}
func (p *Alpha16) At(x, y int) Color { return p.Pixel[y][x] }
func (p *Alpha16) Set(x, y int, c Color) { p.Pixel[y][x] = toAlpha16Color(c).(Alpha16Color) }
func (p *Alpha16) Set(x, y int, c Color) {
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toAlpha16Color(c).(Alpha16Color)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Alpha16) Opaque() bool {
h := len(p.Pixel)
if h > 0 {
w := len(p.Pixel[0])
for y := 0; y < h; y++ {
pix := p.Pixel[y]
for x := 0; x < w; x++ {
if pix[x].A != 0xffff {
return false
}
if p.Rect.Empty() {
return true
}
base := p.Rect.Min.Y * p.Stride
i0, i1 := base+p.Rect.Min.X, base+p.Rect.Max.X
for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
for _, c := range p.Pix[i0:i1] {
if c.A != 0xffff {
return false
}
}
i0 += p.Stride
i1 += p.Stride
}
return true
}
// NewAlpha16 returns a new Alpha16 with the given width and height.
func NewAlpha16(w, h int) *Alpha16 {
buf := make([]Alpha16Color, w*h)
pix := make([][]Alpha16Color, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &Alpha16{pix}
pix := make([]Alpha16Color, w*h)
return &Alpha16{pix, w, Rectangle{ZP, Point{w, h}}}
}
// A Gray is an in-memory image backed by a 2-D slice of GrayColor values.
// An Gray is an in-memory image of GrayColor values.
type Gray struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]GrayColor
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []GrayColor
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *Gray) ColorModel() ColorModel { return GrayColorModel }
func (p *Gray) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *Gray) Bounds() Rectangle { return p.Rect }
func (p *Gray) At(x, y int) Color {
if !p.Rect.Contains(Point{x, y}) {
return GrayColor{}
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
return p.Pix[y*p.Stride+x]
}
func (p *Gray) At(x, y int) Color { return p.Pixel[y][x] }
func (p *Gray) Set(x, y int, c Color) { p.Pixel[y][x] = toGrayColor(c).(GrayColor) }
func (p *Gray) Set(x, y int, c Color) {
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toGrayColor(c).(GrayColor)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Gray) Opaque() bool {
@ -328,32 +364,36 @@ func (p *Gray) Opaque() bool {
// NewGray returns a new Gray with the given width and height.
func NewGray(w, h int) *Gray {
buf := make([]GrayColor, w*h)
pix := make([][]GrayColor, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &Gray{pix}
pix := make([]GrayColor, w*h)
return &Gray{pix, w, Rectangle{ZP, Point{w, h}}}
}
// A Gray16 is an in-memory image backed by a 2-D slice of Gray16Color values.
// An Gray16 is an in-memory image of Gray16Color values.
type Gray16 struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Pixel[y][x].
Pixel [][]Gray16Color
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []Gray16Color
Stride int
// Rect is the image's bounds.
Rect Rectangle
}
func (p *Gray16) ColorModel() ColorModel { return Gray16ColorModel }
func (p *Gray16) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *Gray16) Bounds() Rectangle { return p.Rect }
func (p *Gray16) At(x, y int) Color {
if !p.Rect.Contains(Point{x, y}) {
return Gray16Color{}
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
return p.Pix[y*p.Stride+x]
}
func (p *Gray16) At(x, y int) Color { return p.Pixel[y][x] }
func (p *Gray16) Set(x, y int, c Color) { p.Pixel[y][x] = toGray16Color(c).(Gray16Color) }
func (p *Gray16) Set(x, y int, c Color) {
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = toGray16Color(c).(Gray16Color)
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
func (p *Gray16) Opaque() bool {
@ -362,12 +402,8 @@ func (p *Gray16) Opaque() bool {
// NewGray16 returns a new Gray16 with the given width and height.
func NewGray16(w, h int) *Gray16 {
buf := make([]Gray16Color, w*h)
pix := make([][]Gray16Color, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &Gray16{pix}
pix := make([]Gray16Color, w*h)
return &Gray16{pix, w, Rectangle{ZP, Point{w, h}}}
}
// A PalettedColorModel represents a fixed palette of colors.
@ -409,28 +445,41 @@ func (p PalettedColorModel) Convert(c Color) Color {
// A Paletted is an in-memory image backed by a 2-D slice of uint8 values and a PalettedColorModel.
type Paletted struct {
// The Pixel field's indices are y first, then x, so that At(x, y) == Palette[Pixel[y][x]].
Pixel [][]uint8
// Pix holds the image's pixels. The pixel at (x, y) is Pix[y*Stride+x].
Pix []uint8
Stride int
// Rect is the image's bounds.
Rect Rectangle
// Palette is the image's palette.
Palette PalettedColorModel
}
func (p *Paletted) ColorModel() ColorModel { return p.Palette }
func (p *Paletted) Bounds() Rectangle {
if len(p.Pixel) == 0 {
return ZR
func (p *Paletted) Bounds() Rectangle { return p.Rect }
func (p *Paletted) At(x, y int) Color {
if len(p.Palette) == 0 {
return nil
}
return Rectangle{ZP, Point{len(p.Pixel[0]), len(p.Pixel)}}
if !p.Rect.Contains(Point{x, y}) {
return p.Palette[0]
}
return p.Palette[p.Pix[y*p.Stride+x]]
}
func (p *Paletted) At(x, y int) Color { return p.Palette[p.Pixel[y][x]] }
func (p *Paletted) ColorIndexAt(x, y int) uint8 {
return p.Pixel[y][x]
if !p.Rect.Contains(Point{x, y}) {
return 0
}
return p.Pix[y*p.Stride+x]
}
func (p *Paletted) SetColorIndex(x, y int, index uint8) {
p.Pixel[y][x] = index
if !p.Rect.Contains(Point{x, y}) {
return
}
p.Pix[y*p.Stride+x] = index
}
// Opaque scans the entire image and returns whether or not it is fully opaque.
@ -446,10 +495,6 @@ func (p *Paletted) Opaque() bool {
// NewPaletted returns a new Paletted with the given width, height and palette.
func NewPaletted(w, h int, m PalettedColorModel) *Paletted {
buf := make([]uint8, w*h)
pix := make([][]uint8, h)
for y := range pix {
pix[y] = buf[w*y : w*(y+1)]
}
return &Paletted{pix, m}
pix := make([]uint8, w*h)
return &Paletted{pix, w, Rectangle{ZP, Point{w, h}}, m}
}

View File

@ -206,7 +206,7 @@ func (d *decoder) calcPixel(px, py, lumaBlock, lumaIndex, chromaIndex int) {
} else if b > 255 {
b = 255
}
d.image.Pixel[py][px] = image.RGBAColor{uint8(r), uint8(g), uint8(b), 0xff}
d.image.Pix[py*d.image.Stride+px] = image.RGBAColor{uint8(r), uint8(g), uint8(b), 0xff}
}
// Convert the MCU from YCbCr to RGB.