1 files changed, 247 insertions, 0 deletions
diff --git a/mod/lightpics/vendors/jquery-file-upload/server/gae-go/resize/resize.go b/mod/lightpics/vendors/jquery-file-upload/server/gae-go/resize/resize.go
new file mode 100644
index 000000000..dcb627870
--- /dev/null
+++ b/mod/lightpics/vendors/jquery-file-upload/server/gae-go/resize/resize.go
@@ -0,0 +1,247 @@
+// Copyright 2011 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 resize
+
+import (
+	"image"
+	"image/color"
+)
+
+// Resize returns a scaled copy of the image slice r of m.
+// The returned image has width w and height h.
+func Resize(m image.Image, r image.Rectangle, w, h int) image.Image {
+	if w < 0 || h < 0 {
+		return nil
+	}
+	if w == 0 || h == 0 || r.Dx() <= 0 || r.Dy() <= 0 {
+		return image.NewRGBA64(image.Rect(0, 0, w, h))
+	}
+	switch m := m.(type) {
+	case *image.RGBA:
+		return resizeRGBA(m, r, w, h)
+	case *image.YCbCr:
+		if m, ok := resizeYCbCr(m, r, w, h); ok {
+			return m
+		}
+	}
+	ww, hh := uint64(w), uint64(h)
+	dx, dy := uint64(r.Dx()), uint64(r.Dy())
+	// The scaling algorithm is to nearest-neighbor magnify the dx * dy source
+	// to a (ww*dx) * (hh*dy) intermediate image and then minify the intermediate
+	// image back down to a ww * hh destination with a simple box filter.
+	// The intermediate image is implied, we do not physically allocate a slice
+	// of length ww*dx*hh*dy.
+	// For example, consider a 4*3 source image. Label its pixels from a-l:
+	//	abcd
+	//	efgh
+	//	ijkl
+	// To resize this to a 3*2 destination image, the intermediate is 12*6.
+	// Whitespace has been added to delineate the destination pixels:
+	//	aaab bbcc cddd
+	//	aaab bbcc cddd
+	//	eeef ffgg ghhh
+	//
+	//	eeef ffgg ghhh
+	//	iiij jjkk klll
+	//	iiij jjkk klll
+	// Thus, the 'b' source pixel contributes one third of its value to the
+	// (0, 0) destination pixel and two thirds to (1, 0).
+	// The implementation is a two-step process. First, the source pixels are
+	// iterated over and each source pixel's contribution to 1 or more
+	// destination pixels are summed. Second, the sums are divided by a scaling
+	// factor to yield the destination pixels.
+	// TODO: By interleaving the two steps, instead of doing all of
+	// step 1 first and all of step 2 second, we could allocate a smaller sum
+	// slice of length 4*w*2 instead of 4*w*h, although the resultant code
+	// would become more complicated.
+	n, sum := dx*dy, make([]uint64, 4*w*h)
+	for y := r.Min.Y; y < r.Max.Y; y++ {
+		for x := r.Min.X; x < r.Max.X; x++ {
+			// Get the source pixel.
+			r32, g32, b32, a32 := m.At(x, y).RGBA()
+			r64 := uint64(r32)
+			g64 := uint64(g32)
+			b64 := uint64(b32)
+			a64 := uint64(a32)
+			// Spread the source pixel over 1 or more destination rows.
+			py := uint64(y) * hh
+			for remy := hh; remy > 0; {
+				qy := dy - (py % dy)
+				if qy > remy {
+					qy = remy
+				}
+				// Spread the source pixel over 1 or more destination columns.
+				px := uint64(x) * ww
+				index := 4 * ((py/dy)*ww + (px / dx))
+				for remx := ww; remx > 0; {
+					qx := dx - (px % dx)
+					if qx > remx {
+						qx = remx
+					}
+					sum[index+0] += r64 * qx * qy
+					sum[index+1] += g64 * qx * qy
+					sum[index+2] += b64 * qx * qy
+					sum[index+3] += a64 * qx * qy
+					index += 4
+					px += qx
+					remx -= qx
+				}
+				py += qy
+				remy -= qy
+			}
+		}
+	}
+	return average(sum, w, h, n*0x0101)
+}
+
+// average convert the sums to averages and returns the result.
+func average(sum []uint64, w, h int, n uint64) image.Image {
+	ret := image.NewRGBA(image.Rect(0, 0, w, h))
+	for y := 0; y < h; y++ {
+		for x := 0; x < w; x++ {
+			index := 4 * (y*w + x)
+			ret.SetRGBA(x, y, color.RGBA{
+				uint8(sum[index+0] / n),
+				uint8(sum[index+1] / n),
+				uint8(sum[index+2] / n),
+				uint8(sum[index+3] / n),
+			})
+		}
+	}
+	return ret
+}
+
+// resizeYCbCr returns a scaled copy of the YCbCr image slice r of m.
+// The returned image has width w and height h.
+func resizeYCbCr(m *image.YCbCr, r image.Rectangle, w, h int) (image.Image, bool) {
+	var verticalRes int
+	switch m.SubsampleRatio {
+	case image.YCbCrSubsampleRatio420:
+		verticalRes = 2
+	case image.YCbCrSubsampleRatio422:
+		verticalRes = 1
+	default:
+		return nil, false
+	}
+	ww, hh := uint64(w), uint64(h)
+	dx, dy := uint64(r.Dx()), uint64(r.Dy())
+	// See comment in Resize.
+	n, sum := dx*dy, make([]uint64, 4*w*h)
+	for y := r.Min.Y; y < r.Max.Y; y++ {
+		Y := m.Y[y*m.YStride:]
+		Cb := m.Cb[y/verticalRes*m.CStride:]
+		Cr := m.Cr[y/verticalRes*m.CStride:]
+		for x := r.Min.X; x < r.Max.X; x++ {
+			// Get the source pixel.
+			r8, g8, b8 := color.YCbCrToRGB(Y[x], Cb[x/2], Cr[x/2])
+			r64 := uint64(r8)
+			g64 := uint64(g8)
+			b64 := uint64(b8)
+			// Spread the source pixel over 1 or more destination rows.
+			py := uint64(y) * hh
+			for remy := hh; remy > 0; {
+				qy := dy - (py % dy)
+				if qy > remy {
+					qy = remy
+				}
+				// Spread the source pixel over 1 or more destination columns.
+				px := uint64(x) * ww
+				index := 4 * ((py/dy)*ww + (px / dx))
+				for remx := ww; remx > 0; {
+					qx := dx - (px % dx)
+					if qx > remx {
+						qx = remx
+					}
+					qxy := qx * qy
+					sum[index+0] += r64 * qxy
+					sum[index+1] += g64 * qxy
+					sum[index+2] += b64 * qxy
+					sum[index+3] += 0xFFFF * qxy
+					index += 4
+					px += qx
+					remx -= qx
+				}
+				py += qy
+				remy -= qy
+			}
+		}
+	}
+	return average(sum, w, h, n), true
+}
+
+// resizeRGBA returns a scaled copy of the RGBA image slice r of m.
+// The returned image has width w and height h.
+func resizeRGBA(m *image.RGBA, r image.Rectangle, w, h int) image.Image {
+	ww, hh := uint64(w), uint64(h)
+	dx, dy := uint64(r.Dx()), uint64(r.Dy())
+	// See comment in Resize.
+	n, sum := dx*dy, make([]uint64, 4*w*h)
+	for y := r.Min.Y; y < r.Max.Y; y++ {
+		pixOffset := m.PixOffset(r.Min.X, y)
+		for x := r.Min.X; x < r.Max.X; x++ {
+			// Get the source pixel.
+			r64 := uint64(m.Pix[pixOffset+0])
+			g64 := uint64(m.Pix[pixOffset+1])
+			b64 := uint64(m.Pix[pixOffset+2])
+			a64 := uint64(m.Pix[pixOffset+3])
+			pixOffset += 4
+			// Spread the source pixel over 1 or more destination rows.
+			py := uint64(y) * hh
+			for remy := hh; remy > 0; {
+				qy := dy - (py % dy)
+				if qy > remy {
+					qy = remy
+				}
+				// Spread the source pixel over 1 or more destination columns.
+				px := uint64(x) * ww
+				index := 4 * ((py/dy)*ww + (px / dx))
+				for remx := ww; remx > 0; {
+					qx := dx - (px % dx)
+					if qx > remx {
+						qx = remx
+					}
+					qxy := qx * qy
+					sum[index+0] += r64 * qxy
+					sum[index+1] += g64 * qxy
+					sum[index+2] += b64 * qxy
+					sum[index+3] += a64 * qxy
+					index += 4
+					px += qx
+					remx -= qx
+				}
+				py += qy
+				remy -= qy
+			}
+		}
+	}
+	return average(sum, w, h, n)
+}
+
+// Resample returns a resampled copy of the image slice r of m.
+// The returned image has width w and height h.
+func Resample(m image.Image, r image.Rectangle, w, h int) image.Image {
+	if w < 0 || h < 0 {
+		return nil
+	}
+	if w == 0 || h == 0 || r.Dx() <= 0 || r.Dy() <= 0 {
+		return image.NewRGBA64(image.Rect(0, 0, w, h))
+	}
+	curw, curh := r.Dx(), r.Dy()
+	img := image.NewRGBA(image.Rect(0, 0, w, h))
+	for y := 0; y < h; y++ {
+		for x := 0; x < w; x++ {
+			// Get a source pixel.
+			subx := x * curw / w
+			suby := y * curh / h
+			r32, g32, b32, a32 := m.At(subx, suby).RGBA()
+			r := uint8(r32 >> 8)
+			g := uint8(g32 >> 8)
+			b := uint8(b32 >> 8)
+			a := uint8(a32 >> 8)
+			img.SetRGBA(x, y, color.RGBA{r, g, b, a})
+		}
+	}
+	return img
+}