robocar-road/road/detect.go

488 lines
14 KiB
Go

package road
import (
"github.com/cyrilix/robocar-protobuf/go/events"
"go.uber.org/zap"
"gocv.io/x/gocv"
"image"
"image/color"
"math"
)
type DetectorOption func(*Detector)
func WithWhiteFilter(lowThreshold int, highThreshold int) DetectorOption {
return func(d *Detector) {
err := d.lowerWhite.Close()
if err != nil {
zap.S().Errorf("unable to close lower white filter: %v", err)
}
err = d.upperWhite.Close()
if err != nil {
zap.S().Errorf("unable to close upper white filter: %v", err)
}
d.lowerWhite = gocv.NewMatFromScalar(gocv.Scalar{Val1: float64(lowThreshold), Val2: float64(lowThreshold), Val3: float64(lowThreshold), Val4: float64(lowThreshold)}, gocv.MatTypeCV8U)
d.upperWhite = gocv.NewMatFromScalar(gocv.Scalar{Val1: float64(highThreshold), Val2: float64(highThreshold), Val3: float64(highThreshold), Val4: float64(highThreshold)}, gocv.MatTypeCV8U)
}
}
func WithYellowFilter(lower gocv.Mat, upper gocv.Mat) DetectorOption {
return func(d *Detector) {
err := d.lowerYellow.Close()
if err != nil {
zap.S().Errorf("unable to close lower yellow filter: %v", err)
}
err = d.upperYellow.Close()
if err != nil {
zap.S().Errorf("unable to close upper yellow filter: %v", err)
}
d.lowerYellow = lower
d.upperYellow = upper
}
}
func WithRegionOfInterest(imgWidth int, imgHeight int, horizon int) DetectorOption {
roi := buildRegionOfInterest(imgWidth, imgHeight, horizon)
return func(d *Detector) {
err := d.roiMask.Close()
if err != nil {
zap.S().Errorf("unable to close roi mask: %v", err)
}
d.roiMask = *roi
}
}
func WithPointOnRoad(pt image.Point) DetectorOption {
return func(d *Detector) {
d.pointOnRoad = pt
}
}
func WithCanny(lowThreshold int, highThreshold int) DetectorOption {
return func(d *Detector) {
d.cannyLowThreshold = float32(lowThreshold)
d.cannyHighThreshold = float32(highThreshold)
}
}
func WithGaussianBlur(kernelSize int) DetectorOption {
return func(d *Detector) {
d.gaussianBlurKernelSize = kernelSize
}
}
func WithHoughLines(rho int, theta float32, threshold int, minLineLength int, maxLineGap int) DetectorOption {
return func(d *Detector) {
d.houghLinesRho = float32(rho)
d.houghLinesTheta = theta
d.houghLinesThreshold = threshold
d.houghLinesMinLineLength = minLineLength
d.houghLinesMaxLineGap = maxLineGap
}
}
func NewDetector(options ...DetectorOption) *Detector {
whiteThreshold := 20.
roiMask := buildRegionOfInterest(160, 120, 110)
pointOnRoad := image.Point{X: 160 / 2, Y: 120 - 30}
d := Detector{
lowerWhite: gocv.NewMatFromScalar(gocv.Scalar{Val1: whiteThreshold, Val2: whiteThreshold, Val3: whiteThreshold, Val4: whiteThreshold}, gocv.MatTypeCV8U),
upperWhite: gocv.NewMatFromScalar(gocv.Scalar{Val1: 255., Val2: 255., Val3: 255., Val4: 255.}, gocv.MatTypeCV8U),
lowerYellow: gocv.NewMatFromScalar(gocv.Scalar{Val1: 90., Val2: 100., Val3: 100.}, gocv.MatTypeCV8U),
upperYellow: gocv.NewMatFromScalar(gocv.Scalar{Val1: 110., Val2: 255., Val3: 255.}, gocv.MatTypeCV8U),
cannyLowThreshold: 100.,
cannyHighThreshold: 250.,
gaussianBlurKernelSize: 3,
// Hough Transform
houghLinesRho: 2, // distance resolution in pixels of the Hough grid
houghLinesTheta: 1 * math.Pi / 180, // angular resolution in radians of the Hough grid
houghLinesThreshold: 15, // minimum number of votes (intersections in Hough grid cell)
houghLinesMinLineLength: 10, // minimum number of pixels making up a line
houghLinesMaxLineGap: 20, // maximum gap in pixels between connectable line segments
roiMask: *roiMask,
pointOnRoad: pointOnRoad,
}
for _, option := range options {
option(&d)
}
return &d
}
func buildRegionOfInterest(imgWidth int, imgHeight int, horizon int) *gocv.Mat {
// RegionOfInterest
// defining a blank roiMask to start with
roiMask := gocv.Zeros(imgHeight, imgWidth, gocv.MatTypeCV8U)
vertices := gocv.NewPointsVectorFromPoints(
[][]image.Point{
{
{0, imgHeight - horizon},
{imgWidth, imgHeight - horizon},
{imgWidth, imgHeight},
{0, imgHeight},
},
},
)
defer vertices.Close()
ignoreMaskColor := color.RGBA{R: 255, G: 255, B: 255, A: 255}
gocv.FillPoly(&roiMask, vertices, ignoreMaskColor)
return &roiMask
}
type Detector struct {
whiteThreshold float64
lowerWhite gocv.Mat
upperWhite gocv.Mat
lowerYellow gocv.Mat
upperYellow gocv.Mat
cannyLowThreshold, cannyHighThreshold float32
gaussianBlurKernelSize int
// Hough lines parameters
houghLinesRho, houghLinesTheta float32
houghLinesThreshold int
houghLinesMinLineLength, houghLinesMaxLineGap int
// Region Of interest
roiMask gocv.Mat
pointOnRoad image.Point
}
func (d *Detector) Close() {
defer func(lowerWhite *gocv.Mat) {
err := lowerWhite.Close()
if err != nil {
zap.S().Errorf("unable to close lowerWhite: %v", err)
}
}(&d.lowerWhite)
defer func(upperWhite *gocv.Mat) {
err := upperWhite.Close()
if err != nil {
zap.S().Errorf("unable to close upperWhite: %v", err)
}
}(&d.upperWhite)
defer func(lowerYellow *gocv.Mat) {
err := lowerYellow.Close()
if err != nil {
zap.S().Errorf("unable to close lowerYellow: %v", err)
}
}(&d.lowerYellow)
defer func(upperYellow *gocv.Mat) {
err := upperYellow.Close()
if err != nil {
zap.S().Errorf("unable to close upperYellow: %v", err)
}
}(&d.upperYellow)
defer func(roiMask *gocv.Mat) {
err := roiMask.Close()
if err != nil {
zap.S().Errorf("unable to close roiMask: %v", err)
}
}(&d.roiMask)
}
func (d *Detector) Detect(img *gocv.Mat) ([]*events.Point, *events.Ellipse) {
// Only keep white and yellow pixels in the image, all other pixels become black
imgFiltered := d.filterColors(img)
defer func(imgFiltered *gocv.Mat) {
err := imgFiltered.Close()
if err != nil {
zap.S().Errorf("unable to close imgFiltered: %v", err)
}
}(imgFiltered)
// # Read in and grayscale the image
imgGray := d.grayscale(imgFiltered)
defer func(imgGray *gocv.Mat) {
err := imgGray.Close()
if err != nil {
zap.S().Errorf("unable to close imgGray: %v", err)
}
}(imgGray)
// Apply Gaussian smoothing
blurGray := d.gaussianBlur(imgGray)
defer func(blurGray *gocv.Mat) {
err := blurGray.Close()
if err != nil {
zap.S().Errorf("unable to close blurGray: %v", err)
}
}(blurGray)
// Apply Canny Edge Detector
edges := d.canny(blurGray)
defer func(edges *gocv.Mat) {
err := edges.Close()
if err != nil {
zap.S().Errorf("unable to close edges: %v", err)
}
}(edges)
maskedEdges := d.applyRegionOfInterest(edges)
defer func(maskedEdges *gocv.Mat) {
err := maskedEdges.Close()
if err != nil {
zap.S().Errorf("unable to close maskedEdges: %v", err)
}
}(maskedEdges)
// Run Hough on edge detected image
road, ellipsis := d.getRoadShapeWithHoughLines(maskedEdges)
return road, ellipsis
}
// Filter the image to include only yellow and white pixels
func (d *Detector) filterColors(img *gocv.Mat) *gocv.Mat {
// Filter white pixels
whiteMask := gocv.NewMatWithSize(img.Rows(), img.Cols(), gocv.MatTypeCV8UC3)
defer func(whiteMask *gocv.Mat) {
err := whiteMask.Close()
if err != nil {
zap.S().Errorf("unable to close whiteMask: %v", err)
}
}(&whiteMask)
gocv.InRange(*img, d.lowerWhite, d.upperWhite, &whiteMask)
// Convert one channel result to 3 channel mask
gocv.Merge([]gocv.Mat{whiteMask, whiteMask, whiteMask}, &whiteMask)
whiteImage := gocv.NewMatWithSize(img.Rows(), img.Cols(), img.Type())
defer func(whiteImage *gocv.Mat) {
err := whiteImage.Close()
if err != nil {
zap.S().Errorf("unable to close whiteImage: %v", err)
}
}(&whiteImage)
gocv.BitwiseAnd(*img, whiteMask, &whiteImage)
// Filter yellow pixels
hsv := gocv.NewMatWithSize(img.Rows(), img.Cols(), img.Type())
defer func(hsv *gocv.Mat) {
err := hsv.Close()
if err != nil {
zap.S().Errorf("unable to close hsv: %v", err)
}
}(&hsv)
gocv.CvtColor(*img, &hsv, gocv.ColorBGRToHSV)
yellowMask := gocv.NewMatWithSize(img.Rows(), img.Cols(), img.Type())
defer func(yellowMask *gocv.Mat) {
err := yellowMask.Close()
if err != nil {
zap.S().Errorf("unable to close yellowMask: %v", err)
}
}(&yellowMask)
gocv.InRange(hsv, d.lowerYellow, d.upperYellow, &yellowMask)
// Convert one channel result to 3 channel mask
gocv.Merge([]gocv.Mat{yellowMask, yellowMask, yellowMask}, &yellowMask)
yellowImage := gocv.NewMatWithSize(img.Rows(), img.Cols(), img.Type())
defer func(yellowImage *gocv.Mat) {
err := yellowImage.Close()
if err != nil {
zap.S().Errorf("unable to close yellowImage: %v", err)
}
}(&yellowImage)
gocv.BitwiseAnd(*img, yellowMask, &yellowImage)
// Combine the two above images
image2 := gocv.NewMatWithSize(img.Rows(), img.Cols(), img.Type())
gocv.AddWeighted(whiteImage, 1., yellowImage, 1., 0., &image2)
return &image2
}
/*
Applies the Grayscale transform
This will return an image with only one color channel
but NOTE: to see the returned image as grayscale
you should call plt.imshow(gray, cmap='gray')
*/
func (d *Detector) grayscale(img *gocv.Mat) *gocv.Mat {
grayImg := gocv.NewMatWithSize(img.Rows(), img.Cols(), gocv.MatTypeCV8U)
gocv.CvtColor(*img, &grayImg, gocv.ColorBGRToGray)
return &grayImg
}
/* Applies the Canny transform */
func (d *Detector) canny(img *gocv.Mat) *gocv.Mat {
edges := gocv.NewMatWithSize(img.Rows(), img.Cols(), gocv.MatTypeCV8U)
gocv.Canny(*img, &edges, d.cannyLowThreshold, d.cannyHighThreshold)
return &edges
}
func (d *Detector) gaussianBlur(img *gocv.Mat) *gocv.Mat {
blur := gocv.NewMatWithSize(img.Rows(), img.Cols(), gocv.MatTypeCV8U)
gocv.GaussianBlur(*img, &blur, image.Point{X: d.gaussianBlurKernelSize, Y: d.gaussianBlurKernelSize}, 0., 0., gocv.BorderDefault)
return &blur
}
func (d *Detector) getRoadShapeWithHoughLines(img *gocv.Mat) ([]*events.Point, *events.Ellipse) {
lines := gocv.NewMat()
defer func(lines *gocv.Mat) {
err := lines.Close()
if err != nil {
zap.S().Errorf("unable to close lines mar: %v", err)
}
}(&lines)
gocv.HoughLinesP(*img, &lines, d.houghLinesRho, d.houghLinesTheta, d.houghLinesThreshold)
// Generate new image with detected edges
imgLines := gocv.NewMatWithSize(img.Rows(), img.Cols(), gocv.MatTypeCV8U)
defer func(imgLines *gocv.Mat) {
err := imgLines.Close()
if err != nil {
zap.S().Errorf("unable to close imgLines: %v", err)
}
}(&imgLines)
for i := 0; i < lines.Rows(); i++ {
x1 := lines.GetIntAt(i, 0)
y1 := lines.GetIntAt(i, 1)
x2 := lines.GetIntAt(i, 2)
y2 := lines.GetIntAt(i, 3)
gocv.Line(&imgLines, image.Point{X: int(x1), Y: int(y1)}, image.Point{X: int(x2), Y: int(y2)}, color.RGBA{
R: 255,
G: 255,
B: 255,
A: 255,
}, 3)
}
// Draw rectangle to add limit on image border
gocv.Rectangle(&imgLines, image.Rectangle{
Min: image.Point{X: 0, Y: 0},
Max: image.Point{X: img.Cols() - 1, Y: img.Rows() - 1},
}, color.RGBA{R: 255, G: 255, B: 255, A: 255}, 1)
kernel := gocv.Ones(8, 8, gocv.MatTypeCV8U)
defer func(kernel *gocv.Mat) {
err := kernel.Close()
if err != nil {
zap.S().Errorf("unable to close kernel: %v", err)
}
}(&kernel)
gocv.Dilate(imgLines, &imgLines, kernel)
gocv.Erode(imgLines, &imgLines, kernel)
cnts := gocv.FindContours(imgLines, gocv.RetrievalList, gocv.ChainApproxSimple)
defer cnts.Close()
for i := 0; i < cnts.Size(); i++ {
cnt := cnts.At(i)
pv := gocv.ApproxPolyDP(cnt, 0.01*gocv.ArcLength(cnt, true), true)
if gocv.PointPolygonTest(pv, d.pointOnRoad, false) > 0 {
ellipse := d.computeEllipsis(&pv)
cntr_result := make([]*events.Point, 0, pv.Size())
for i := 0; i < pv.Size(); i++ {
pt := pv.At(i)
cntr_result = append(cntr_result, &events.Point{X: int32(pt.X), Y: int32(pt.Y)})
}
return cntr_result, ellipse
}
}
return []*events.Point{}, &EllipseNotFound
}
/*
Applies an image mask.
Only keeps the region of the image defined by the polygon
formed from `vertices`. The rest of the image is set to black.
*/
func (d *Detector) applyRegionOfInterest(img *gocv.Mat) *gocv.Mat {
// returning the image only where mask pixels are nonzero
maskedImage := gocv.NewMatWithSize(img.Rows(), img.Cols(), gocv.MatTypeCV8U)
gocv.BitwiseAnd(*img, d.roiMask, &maskedImage)
return &maskedImage
}
var EllipseNotFound = events.Ellipse{Confidence: 0.}
func (d *Detector) computeEllipsis(road *gocv.PointVector) *events.Ellipse {
if road.Size() < 5 {
return &EllipseNotFound
}
rotatedRect := gocv.FitEllipse(*road)
trust := d.computeTrustFromCenter(&rotatedRect.Center)
zap.S().Debugf("Trust: %v", trust)
return &events.Ellipse{
Center: &events.Point{
X: int32(rotatedRect.Center.X),
Y: int32(rotatedRect.Center.Y),
},
Width: int32(rotatedRect.Width),
Height: int32(rotatedRect.Height),
Angle: float32(rotatedRect.Angle),
Confidence: d.computeTrustFromCenter(&rotatedRect.Center),
}
}
func (d *Detector) computeTrustFromCenter(ellipsisCenter *image.Point) float32 {
safeMinX := 48
safeMaxX := 115
safeMinY := 69
safeMaxY := 119
if safeMinX <= ellipsisCenter.X && ellipsisCenter.X <= safeMaxX && safeMinY <= ellipsisCenter.Y && ellipsisCenter.Y <= safeMaxY {
return 1.0
}
if safeMinX <= ellipsisCenter.X && ellipsisCenter.X <= safeMaxX {
return d.computeTrustOnAxis(safeMaxY, safeMinY, ellipsisCenter.Y)
}
if safeMinY <= ellipsisCenter.Y && ellipsisCenter.Y <= safeMaxY {
return d.computeTrustOnAxis(safeMaxX, safeMinX, ellipsisCenter.X)
}
return d.computeTrustOnAxis(safeMaxY, safeMinY, ellipsisCenter.Y) * d.computeTrustOnAxis(safeMaxX, safeMinX, ellipsisCenter.X)
}
func (d *Detector) computeTrustOnAxis(safeMax, safeMin, value int) float32 {
trust := 1.
if value > safeMax {
trust = 1. / float64(value-safeMax)
} else if value < safeMin {
trust = 1. / float64(safeMin-value)
}
trust = trust * 10.
if trust > 0.9 {
trust = 0.9
}
if trust < 0. {
trust = 0.
}
return float32(trust)
}