lordwelch/goimagehash
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staticcheck fixes

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This commit is contained in:
Timmy Welch 2024-08-04 18:24:04 -07:00
parent fb3adaa0a1
commit 5cd3cb8dcf
8 changed files with 115 additions and 94 deletions
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1
hashcompute.go
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@ -40,6 +40,7 @@ func getBuf(size, capacity int) []uint8 {
} }
return buf return buf
} }
func ToGray(img image.Image, pix []uint8) *image.Gray { func ToGray(img image.Image, pix []uint8) *image.Gray {
c := img.Bounds().Dx() * img.Bounds().Dy() c := img.Bounds().Dx() * img.Bounds().Dy()
if cap(pix) < c { if cap(pix) < c {

1
hashcompute_test.go
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@ -49,7 +49,6 @@ func TestHashCompute(t *testing.T) {
} { } {
file1, err := os.Open(tt.img1) file1, err := os.Open(tt.img1)
if err != nil { if err != nil {
} }
defer file1.Close() defer file1.Close()

16
imagehash.go
View File

@ -36,7 +36,7 @@ const (
Unknown Kind = iota Unknown Kind = iota
// AHash is a enum value of the average hash. // AHash is a enum value of the average hash.
AHash AHash
//PHash is a enum value of the perceptual hash. // PHash is a enum value of the perceptual hash.
PHash PHash
// DHash is a enum value of the difference hash. // DHash is a enum value of the difference hash.
DHash DHash
@ -60,7 +60,7 @@ func (h *ImageHash) Distance(other *ImageHash) (int, error) {
return -1, errNoOther return -1, errNoOther
} }
if h.GetKind() != other.GetKind() { if h.GetKind() != other.GetKind() {
return -1, errors.New("Image hashes's kind should be identical") return -1, errors.New("image hashes's kind should be identical")
} }
lhash := h.GetHash() lhash := h.GetHash()
@ -84,8 +84,10 @@ func (h *ImageHash) leftShiftSet(idx int) {
h.hash |= 1 << uint(idx) h.hash |= 1 << uint(idx)
} }
const strFmtHex = "%1s:%016x" const (
const strFmtBin = "%1s:%064b" strFmtHex = "%1s:%016x"
strFmtBin = "%1s:%064b"
)
// Dump method writes a binary serialization into w io.Writer. // Dump method writes a binary serialization into w io.Writer.
func (h *ImageHash) Dump(w io.Writer) error { func (h *ImageHash) Dump(w io.Writer) error {
@ -164,18 +166,18 @@ func (h *ExtImageHash) Bits() int {
// Distance method returns a distance between two big hashes // Distance method returns a distance between two big hashes
func (h *ExtImageHash) Distance(other *ExtImageHash) (int, error) { func (h *ExtImageHash) Distance(other *ExtImageHash) (int, error) {
if h.GetKind() != other.GetKind() { if h.GetKind() != other.GetKind() {
return -1, errors.New("Extended Image hashes's kind should be identical") return -1, errors.New("extended Image hashes's kind should be identical")
} }
if h.Bits() != other.Bits() { if h.Bits() != other.Bits() {
msg := fmt.Sprintf("Extended image hash should has an identical bit size but got %v vs %v", h.Bits(), other.Bits()) msg := fmt.Sprintf("extended image hash should has an identical bit size but got %v vs %v", h.Bits(), other.Bits())
return -1, errors.New(msg) return -1, errors.New(msg)
} }
lHash := h.GetHash() lHash := h.GetHash()
rHash := other.GetHash() rHash := other.GetHash()
if len(lHash) != len(rHash) { if len(lHash) != len(rHash) {
return -1, errors.New("Extended Image hashes's size should be identical") return -1, errors.New("extended Image hashes's size should be identical")
} }
distance := 0 distance := 0

1
transforms/dct.go
View File

@ -97,6 +97,7 @@ func DCT2DFast64(input *[]float64) (flattens [64]float64) {
} }
return return
} }
func DCT2DFast32(input *[]float64) (flattens [64]float64) { func DCT2DFast32(input *[]float64) (flattens [64]float64) {
if len(*input) != 32*32 { if len(*input) != 32*32 {
panic("incorrect input size, wanted 32x32.") panic("incorrect input size, wanted 32x32.")

23
transforms/dct_test.go
View File

@ -43,18 +43,23 @@ func TestDCT2D(t *testing.T) {
for _, tt := range []struct { for _, tt := range []struct {
input [][]float64 input [][]float64
output [][]float64 output [][]float64
w int w, h int
h int
}{ }{
{[][]float64{{1.0, 2.0, 3.0, 4.0}, {
{5.0, 6.0, 7.0, 8.0}, [][]float64{
{9.0, 10.0, 11.0, 12.0}, {1.0, 2.0, 3.0, 4.0},
{13.0, 14.0, 15.0, 16.0}}, {5.0, 6.0, 7.0, 8.0},
[][]float64{{136.0, -12.6172881195958, 0.0, -0.8966830583359305}, {9.0, 10.0, 11.0, 12.0},
{13.0, 14.0, 15.0, 16.0},
},
[][]float64{
{136.0, -12.6172881195958, 0.0, -0.8966830583359305},
{-50.4691524783832, 0.0, 0.0, 0.0}, {-50.4691524783832, 0.0, 0.0, 0.0},
{0.0, 0.0, 0.0, 0.0}, {0.0, 0.0, 0.0, 0.0},
{-3.586732233343722, 0.0, 0.0, 0.0}}, {-3.586732233343722, 0.0, 0.0, 0.0},
4, 4}, },
4, 4,
},
} { } {
out := DCT2D(tt.input, tt.w, tt.h) out := DCT2D(tt.input, tt.w, tt.h)
pass := true pass := true

8
transforms/static.go
View File

@ -86,7 +86,7 @@ func forwardDCT16(input []float64) {
} }
func forwardDCT8(input []float64) { func forwardDCT8(input []float64) {
var a, b = [4]float64{}, [4]float64{} a, b := [4]float64{}, [4]float64{}
x0, y0 := input[0], input[7] x0, y0 := input[0], input[7]
x1, y1 := input[1], input[6] x1, y1 := input[1], input[6]
@ -159,7 +159,8 @@ var (
0.7540148204328366, 0.7312259956095479, 0.708327050840981, 0.6853214346239888, 0.6622126115197529, 0.6390040616320315, 0.61569928008307, 0.5923017764872479, 0.7540148204328366, 0.7312259956095479, 0.708327050840981, 0.6853214346239888, 0.6622126115197529, 0.6390040616320315, 0.61569928008307, 0.5923017764872479,
0.5688150744225436, 0.545242710899898, 0.5215882358305511, 0.4978552114914405, 0.4740472119887347, 0.45016782271958555, 0.4262206398321827, 0.40220926968418386, 0.5688150744225436, 0.545242710899898, 0.5215882358305511, 0.4978552114914405, 0.4740472119887347, 0.45016782271958555, 0.4262206398321827, 0.40220926968418386,
0.37813732829961255, 0.3540084408242977, 0.3298262409799401, 0.3055943705168868, 0.2813164786656985, 0.25699622158758645, 0.23263726182380973, 0.20824326774410945, 0.37813732829961255, 0.3540084408242977, 0.3298262409799401, 0.3055943705168868, 0.2813164786656985, 0.25699622158758645, 0.23263726182380973, 0.20824326774410945,
0.1838179129942654, 0.15936487594286025, 0.1348878391273282, 0.11039048869938006, 0.08587651386988192, 0.06134960635327317, 0.03681345981160964, 0.012271769298309032} 0.1838179129942654, 0.15936487594286025, 0.1348878391273282, 0.11039048869938006, 0.08587651386988192, 0.06134960635327317, 0.03681345981160964, 0.012271769298309032,
}
dct128 = [64]float64{ dct128 = [64]float64{
1.9998494036782892, 1.9986447691766989, 1.9962362258002984, 1.992625224365556, 1.9878139400047121, 1.98180527085556, 1.9746028363157169, 1.9662109748624328, 1.9998494036782892, 1.9986447691766989, 1.9962362258002984, 1.992625224365556, 1.9878139400047121, 1.98180527085556, 1.9746028363157169, 1.9662109748624328,
1.9566347414392553, 1.9458799044111204, 1.9339529420897041, 1.9208610388311316, 1.9066120807083875, 1.8912146507610426, 1.87467802382515, 1.8570121609464312, 1.9566347414392553, 1.9458799044111204, 1.9339529420897041, 1.9208610388311316, 1.9066120807083875, 1.8912146507610426, 1.87467802382515, 1.8570121609464312,
@ -168,7 +169,8 @@ var (
1.3967524988179458, 1.3612019955909063, 1.3248315551803436, 1.287663085779583, 1.249718976284773, 1.211022082808651, 1.1715957149128777, 1.1314636215672265, 1.3967524988179458, 1.3612019955909063, 1.3248315551803436, 1.287663085779583, 1.249718976284773, 1.211022082808651, 1.1715957149128777, 1.1314636215672265,
1.0906499768440931, 1.049179365356938, 1.0070767674514352, 0.9643675441582458, 0.92107742191648, 0.8772324770770554, 0.8328591201952746, 0.7879840801220962, 1.0906499768440931, 1.049179365356938, 1.0070767674514352, 0.9643675441582458, 0.92107742191648, 0.8772324770770554, 0.8328591201952746, 0.7879840801220962,
0.7426343879036752, 0.696837360498869, 0.650620584324526, 0.6040118986384564, 0.5570393787701061, 0.5097313192090293, 0.4621162165613425, 0.4142227523844371, 0.7426343879036752, 0.696837360498869, 0.650620584324526, 0.6040118986384564, 0.5570393787701061, 0.5097313192090293, 0.4621162165613425, 0.4142227523844371,
0.36607977591028207, 0.3177162866677228, 0.26916141701425245, 0.22044441458776637, 0.17159462468887976, 0.12264147260441731, 0.07361444588271798, 0.02454307657143989} 0.36607977591028207, 0.3177162866677228, 0.26916141701425245, 0.22044441458776637, 0.17159462468887976, 0.12264147260441731, 0.07361444588271798, 0.02454307657143989,
}
dct64 = [32]float64{ dct64 = [32]float64{
1.9993976373924083, 1.9945809133573804, 1.9849590691974202, 1.9705552847778824, 1.9514042600770571, 1.9275521315908797, 1.8990563611860733, 1.8659855976694777, 1.9993976373924083, 1.9945809133573804, 1.9849590691974202, 1.9705552847778824, 1.9514042600770571, 1.9275521315908797, 1.8990563611860733, 1.8659855976694777,
1.8284195114070614, 1.7864486023910306, 1.7401739822174227, 1.6897071304994142, 1.6351696263031674, 1.5766928552532127, 1.5144176930129691, 1.448494165902934, 1.8284195114070614, 1.7864486023910306, 1.7401739822174227, 1.6897071304994142, 1.6351696263031674, 1.5766928552532127, 1.5144176930129691, 1.448494165902934,

19
yuv.color.convert.go
View File

@ -16,6 +16,7 @@ const (
func MultHi(v int32, coeff int32) int32 { func MultHi(v int32, coeff int32) int32 {
return (v * coeff) >> 8 return (v * coeff) >> 8
} }
func VP8Clip8(v int32) uint8 { func VP8Clip8(v int32) uint8 {
if (v &^ YUV_MASK2) == 0 { if (v &^ YUV_MASK2) == 0 {
return uint8(v >> YUV_FIX2) return uint8(v >> YUV_FIX2)
@ -25,15 +26,19 @@ func VP8Clip8(v int32) uint8 {
} }
return 0xff return 0xff
} }
func VP8YUVToR(y uint8, v uint8) uint8 { func VP8YUVToR(y uint8, v uint8) uint8 {
return VP8Clip8(MultHi(int32(y), 19077) + MultHi(int32(v), 26149) - 14234) return VP8Clip8(MultHi(int32(y), 19077) + MultHi(int32(v), 26149) - 14234)
} }
func VP8YUVToG(y uint8, u uint8, v uint8) uint8 { func VP8YUVToG(y uint8, u uint8, v uint8) uint8 {
return VP8Clip8(MultHi(int32(y), 19077) - MultHi(int32(u), 6419) - MultHi(int32(v), 13320) + 8708) return VP8Clip8(MultHi(int32(y), 19077) - MultHi(int32(u), 6419) - MultHi(int32(v), 13320) + 8708)
} }
func VP8YUVToB(y uint8, u uint8) uint8 { func VP8YUVToB(y uint8, u uint8) uint8 {
return VP8Clip8(MultHi(int32(y), 19077) + MultHi(int32(u), 33050) - 17685) return VP8Clip8(MultHi(int32(y), 19077) + MultHi(int32(u), 33050) - 17685)
} }
func VP8YuvToRgb(y uint8, u uint8, v uint8) (rgb [3]uint8) { func VP8YuvToRgb(y uint8, u uint8, v uint8) (rgb [3]uint8) {
rgb[0] = uint8(VP8YUVToR(y, v)) rgb[0] = uint8(VP8YUVToR(y, v))
rgb[1] = uint8(VP8YUVToG(y, u, v)) rgb[1] = uint8(VP8YUVToG(y, u, v))
@ -41,6 +46,7 @@ func VP8YuvToRgb(y uint8, u uint8, v uint8) (rgb [3]uint8) {
return rgb return rgb
} }
func VP8YuvToBgr(y uint8, u uint8, v uint8) (bgr [3]uint8) { func VP8YuvToBgr(y uint8, u uint8, v uint8) (bgr [3]uint8) {
bgr[0] = uint8(VP8YUVToB(y, u)) bgr[0] = uint8(VP8YUVToB(y, u))
bgr[1] = uint8(VP8YUVToG(y, u, v)) bgr[1] = uint8(VP8YUVToG(y, u, v))
@ -48,6 +54,7 @@ func VP8YuvToBgr(y uint8, u uint8, v uint8) (bgr [3]uint8) {
return bgr return bgr
} }
func VP8YuvToRgb565(y uint8, u uint8, v uint8) (rgb [2]uint8) { func VP8YuvToRgb565(y uint8, u uint8, v uint8) (rgb [2]uint8) {
var ( var (
r = VP8YUVToR(y, v) r = VP8YUVToR(y, v)
@ -55,13 +62,14 @@ func VP8YuvToRgb565(y uint8, u uint8, v uint8) (rgb [2]uint8) {
b = VP8YUVToB(y, u) b = VP8YUVToB(y, u)
) )
var rg = (r & 0xf8) | (g >> 5) rg := (r & 0xf8) | (g >> 5)
var gb = ((g << 3) & 0xe0) | (b >> 3) gb := ((g << 3) & 0xe0) | (b >> 3)
rgb[0] = uint8(rg) rgb[0] = uint8(rg)
rgb[1] = uint8(gb) rgb[1] = uint8(gb)
return rgb return rgb
} }
func VP8YuvToRgba4444(y uint8, u uint8, v uint8) (argb [2]uint8) { func VP8YuvToRgba4444(y uint8, u uint8, v uint8) (argb [2]uint8) {
var ( var (
r = VP8YUVToR(y, v) r = VP8YUVToR(y, v)
@ -69,13 +77,14 @@ func VP8YuvToRgba4444(y uint8, u uint8, v uint8) (argb [2]uint8) {
b = VP8YUVToB(y, u) b = VP8YUVToB(y, u)
) )
var rg = (r & 0xf0) | (g >> 4) rg := (r & 0xf0) | (g >> 4)
var ba = (b & 0xf0) | 0x0f // overwrite the lower 4 bits ba := (b & 0xf0) | 0x0f // overwrite the lower 4 bits
argb[0] = uint8(rg) argb[0] = uint8(rg)
argb[1] = uint8(ba) argb[1] = uint8(ba)
return argb return argb
} }
func VP8YuvToArgb(y uint8, u uint8, v uint8) (argb [4]uint8) { func VP8YuvToArgb(y uint8, u uint8, v uint8) (argb [4]uint8) {
argb[0] = 0xff argb[0] = 0xff
rgb := VP8YuvToRgb(y, u, v) rgb := VP8YuvToRgb(y, u, v)
@ -83,6 +92,7 @@ func VP8YuvToArgb(y uint8, u uint8, v uint8) (argb [4]uint8) {
return argb return argb
} }
func VP8YuvToBgra(y uint8, u uint8, v uint8) (bgra [4]uint8) { func VP8YuvToBgra(y uint8, u uint8, v uint8) (bgra [4]uint8) {
bgr := VP8YuvToBgr(y, u, v) bgr := VP8YuvToBgr(y, u, v)
copy(bgra[:], bgr[:]) copy(bgra[:], bgr[:])
@ -90,6 +100,7 @@ func VP8YuvToBgra(y uint8, u uint8, v uint8) (bgra [4]uint8) {
return bgra return bgra
} }
func VP8YuvToRgba(y uint8, u uint8, v uint8) (rgba [4]uint8) { func VP8YuvToRgba(y uint8, u uint8, v uint8) (rgba [4]uint8) {
rgb := VP8YuvToRgb(uint8(y), uint8(u), uint8(v)) rgb := VP8YuvToRgb(uint8(y), uint8(u), uint8(v))
copy(rgba[:], rgb[:]) copy(rgba[:], rgb[:])

140
yuv.fancy.upscaling.go
View File

@ -4,132 +4,132 @@ import (
"image" "image"
) )
type WebPUpsampleLinePairFunc func(top_y []uint8, bottom_y []uint8, type WebPUpsampleLinePairFunc func(topY []uint8, bottomY []uint8,
top_u []uint8, top_v []uint8, topU []uint8, topV []uint8,
bottom_u []uint8, bottom_v []uint8, bottomU []uint8, bottomV []uint8,
top_dst []uint8, bottom_dst []uint8, len int) topDst []uint8, bottomDst []uint8, len int)
func FancyUpscale(yuv *image.YCbCr) *image.RGBA { func FancyUpscale(yuv *image.YCbCr) *image.RGBA {
rgb := image.NewRGBA(image.Rect(0, 0, yuv.Rect.Dx(), yuv.Rect.Dy())) rgb := image.NewRGBA(image.Rect(0, 0, yuv.Rect.Dx(), yuv.Rect.Dy()))
var ( var (
upsample WebPUpsampleLinePairFunc = UpsampleRgbaLinePair upsample WebPUpsampleLinePairFunc = UpsampleRgbaLinePair
last_row int = yuv.Rect.Dy() lastRow = yuv.Rect.Dy()
mb_w int = yuv.Rect.Dx() mbW = yuv.Rect.Dx()
) )
// First line is special cased. We mirror the u/v samples at boundary. // First line is special cased. We mirror the u/v samples at boundary.
upsample(yuv.Y[:yuv.YStride], nil, upsample(yuv.Y[:yuv.YStride], nil,
yuv.Cb[:yuv.CStride], yuv.Cr[:yuv.CStride], yuv.Cb[:yuv.CStride], yuv.Cr[:yuv.CStride],
yuv.Cb[:yuv.CStride], yuv.Cr[:yuv.CStride], yuv.Cb[:yuv.CStride], yuv.Cr[:yuv.CStride],
rgb.Pix[:rgb.Stride], nil, rgb.Pix[:rgb.Stride], nil,
mb_w, mbW,
) )
var ( var (
top_c int topC int
bottom_c int bottomC int
top_y int topY int
bottom_y int bottomY int
top_dst int topDst int
bottom_dst int bottomDst int
) )
// Loop over each output pairs of row. // Loop over each output pairs of row.
for row := 1; row+1 < last_row; row += 2 { for row := 1; row+1 < lastRow; row += 2 {
top_c = yuv.COffset(0, row) topC = yuv.COffset(0, row)
bottom_c = top_c + yuv.CStride bottomC = topC + yuv.CStride
top_y = yuv.YOffset(0, row) topY = yuv.YOffset(0, row)
bottom_y = top_y + yuv.YStride bottomY = topY + yuv.YStride
top_dst = rgb.PixOffset(0, row) topDst = rgb.PixOffset(0, row)
bottom_dst = top_dst + rgb.Stride bottomDst = topDst + rgb.Stride
upsample(yuv.Y[top_y:bottom_y], yuv.Y[bottom_y:bottom_y+yuv.YStride], upsample(yuv.Y[topY:bottomY], yuv.Y[bottomY:bottomY+yuv.YStride],
yuv.Cb[top_c:bottom_c], yuv.Cr[top_c:bottom_c], yuv.Cb[topC:bottomC], yuv.Cr[topC:bottomC],
yuv.Cb[bottom_c:bottom_c+yuv.CStride], yuv.Cr[bottom_c:bottom_c+yuv.CStride], yuv.Cb[bottomC:bottomC+yuv.CStride], yuv.Cr[bottomC:bottomC+yuv.CStride],
rgb.Pix[top_dst:bottom_dst], rgb.Pix[bottom_dst:bottom_dst+rgb.Stride], rgb.Pix[topDst:bottomDst], rgb.Pix[bottomDst:bottomDst+rgb.Stride],
mb_w, mbW,
) )
} }
// Process the very last row of even-sized picture // Process the very last row of even-sized picture
if last_row%2 == 0 { if lastRow%2 == 0 {
upsample(yuv.Y[len(yuv.Y)-yuv.YStride:], nil, upsample(yuv.Y[len(yuv.Y)-yuv.YStride:], nil,
yuv.Cb[len(yuv.Cb)-yuv.CStride:], yuv.Cr[len(yuv.Cr)-yuv.CStride:], yuv.Cb[len(yuv.Cb)-yuv.CStride:], yuv.Cr[len(yuv.Cr)-yuv.CStride:],
yuv.Cb[len(yuv.Cb)-yuv.CStride:], yuv.Cr[len(yuv.Cr)-yuv.CStride:], yuv.Cb[len(yuv.Cb)-yuv.CStride:], yuv.Cr[len(yuv.Cr)-yuv.CStride:],
rgb.Pix[len(rgb.Pix)-rgb.Stride:], nil, rgb.Pix[len(rgb.Pix)-rgb.Stride:], nil,
mb_w, mbW,
) )
} }
return rgb return rgb
} }
func UpsampleRgbaLinePair(top_y []uint8, bottom_y []uint8, func UpsampleRgbaLinePair(topY []uint8, bottomY []uint8,
top_u []uint8, top_v []uint8, topU []uint8, topV []uint8,
bottom_u []uint8, bottom_v []uint8, bottomU []uint8, bottomV []uint8,
top_dst []uint8, bottom_dst []uint8, rowLength int, topDst []uint8, bottomDst []uint8, rowLength int,
) { ) {
var ( var (
x int x int
last_pixel_pair int = (rowLength - 1) >> 1 lastPixelPair = (rowLength - 1) >> 1
tl_uv uint32 = (uint32(top_u[0]) | (uint32(top_v[0]) << 16)) /* top-left sample */ tlUV = (uint32(topU[0]) | (uint32(topV[0]) << 16)) /* top-left sample */
l_uv uint32 = (uint32(bottom_u[0]) | (uint32(bottom_v[0]) << 16)) /* left-sample */ lUV = (uint32(bottomU[0]) | (uint32(bottomV[0]) << 16)) /* left-sample */
) )
{ {
var uv0 uint32 = (3*tl_uv + l_uv + 0x00020002) >> 2 uv0 := (3*tlUV + lUV + 0x00020002) >> 2
dst := VP8YuvToRgba(top_y[0], uint8(uv0&0xff), uint8((uv0 >> 16))) dst := VP8YuvToRgba(topY[0], uint8(uv0&0xff), uint8((uv0 >> 16)))
copy(top_dst[0:], dst[:]) copy(topDst[0:], dst[:])
} }
if bottom_y != nil { if bottomY != nil {
var uv0 uint32 = (3*l_uv + tl_uv + 0x00020002) >> 2 uv0 := (3*lUV + tlUV + 0x00020002) >> 2
dst := VP8YuvToRgba(bottom_y[0], uint8(uv0&0xff), uint8(uv0>>16)) dst := VP8YuvToRgba(bottomY[0], uint8(uv0&0xff), uint8(uv0>>16))
copy(bottom_dst[0:], dst[:]) copy(bottomDst[0:], dst[:])
} }
for x = 1; x <= last_pixel_pair; x++ { for x = 1; x <= lastPixelPair; x++ {
var ( var (
t_uv uint32 = (uint32(top_u[x]) | (uint32(top_v[x]) << 16)) /* top sample */ tUV = (uint32(topU[x]) | (uint32(topV[x]) << 16)) /* top sample */
uv uint32 = (uint32(bottom_u[x]) | (uint32(bottom_v[x]) << 16)) /* sample */ uv = (uint32(bottomU[x]) | (uint32(bottomV[x]) << 16)) /* sample */
/* precompute invariant values associated with first and second diagonals*/ /* precompute invariant values associated with first and second diagonals*/
avg uint32 = tl_uv + t_uv + l_uv + uv + 0x00080008 avg = tlUV + tUV + lUV + uv + 0x00080008
diag_12 uint32 = (avg + 2*(t_uv+l_uv)) >> 3 diag12 = (avg + 2*(tUV+lUV)) >> 3
diag_03 uint32 = (avg + 2*(tl_uv+uv)) >> 3 diag03 = (avg + 2*(tlUV+uv)) >> 3
) )
{ {
var ( var (
uv0 uint32 = (diag_12 + tl_uv) >> 1 uv0 = (diag12 + tlUV) >> 1
uv1 uint32 = (diag_03 + t_uv) >> 1 uv1 = (diag03 + tUV) >> 1
) )
dst := VP8YuvToRgba(top_y[2*x-1], uint8(uv0&0xff), uint8(uv0>>16)) dst := VP8YuvToRgba(topY[2*x-1], uint8(uv0&0xff), uint8(uv0>>16))
copy(top_dst[(2*x-1)*4:], dst[:]) copy(topDst[(2*x-1)*4:], dst[:])
dst = VP8YuvToRgba(top_y[2*x-0], uint8(uv1&0xff), uint8(uv1>>16)) dst = VP8YuvToRgba(topY[2*x-0], uint8(uv1&0xff), uint8(uv1>>16))
copy(top_dst[(2*x-0)*4:], dst[:]) copy(topDst[(2*x-0)*4:], dst[:])
} }
if bottom_y != nil { if bottomY != nil {
var ( var (
uv0 uint32 = (diag_03 + l_uv) >> 1 uv0 = (diag03 + lUV) >> 1
uv1 uint32 = (diag_12 + uv) >> 1 uv1 = (diag12 + uv) >> 1
) )
dst := VP8YuvToRgba(bottom_y[2*x-1], uint8(uv0&0xff), uint8(uv0>>16)) dst := VP8YuvToRgba(bottomY[2*x-1], uint8(uv0&0xff), uint8(uv0>>16))
copy(bottom_dst[(2*x-1)*4:], dst[:]) copy(bottomDst[(2*x-1)*4:], dst[:])
dst = VP8YuvToRgba(bottom_y[2*x+0], uint8(uv1&0xff), uint8(uv1>>16)) dst = VP8YuvToRgba(bottomY[2*x+0], uint8(uv1&0xff), uint8(uv1>>16))
copy(bottom_dst[(2*x+0)*4:], dst[:]) copy(bottomDst[(2*x+0)*4:], dst[:])
} }
tl_uv = t_uv tlUV = tUV
l_uv = uv lUV = uv
} }
if rowLength%2 == 0 { if rowLength%2 == 0 {
{ {
var uv0 uint32 = (3*tl_uv + l_uv + 0x00020002) >> 2 uv0 := (3*tlUV + lUV + 0x00020002) >> 2
dst := VP8YuvToRgba(top_y[rowLength-1], uint8(uv0&0xff), uint8(uv0>>16)) dst := VP8YuvToRgba(topY[rowLength-1], uint8(uv0&0xff), uint8(uv0>>16))
copy(top_dst[(rowLength-1)*4:], dst[:]) copy(topDst[(rowLength-1)*4:], dst[:])
} }
if bottom_y != nil { if bottomY != nil {
var uv0 uint32 = (3*l_uv + tl_uv + 0x00020002) >> 2 uv0 := (3*lUV + tlUV + 0x00020002) >> 2
dst := VP8YuvToRgba(bottom_y[rowLength-1], uint8(uv0&0xff), uint8(uv0>>16)) dst := VP8YuvToRgba(bottomY[rowLength-1], uint8(uv0&0xff), uint8(uv0>>16))
copy(bottom_dst[(rowLength-1)*4:], dst[:]) copy(bottomDst[(rowLength-1)*4:], dst[:])
} }
} }
} }