// Score a collection of lines as a possible license plate region.
// If any segments are missing, extrapolate the missing pieces
void PlateCorners::scoreHorizontals(int h1, int h2)
{
ScoreKeeper scoreKeeper;
LineSegment top;
LineSegment bottom;
float charHeightToPlateHeightRatio = pipelineData->config->plateHeightMM / pipelineData->config->charHeightMM;
float idealPixelHeight = tlc.charHeight * charHeightToPlateHeightRatio;
float confidenceDiff = 0;
float missingSegmentPenalty = 0;
if (h1 == NO_LINE && h2 == NO_LINE)
{
// return;
top = tlc.centerHorizontalLine.getParallelLine(idealPixelHeight / 2);
bottom = tlc.centerHorizontalLine.getParallelLine(-1 * idealPixelHeight / 2 );
missingSegmentPenalty = 2;
confidenceDiff += 2;
}
else if (h1 != NO_LINE && h2 != NO_LINE)
{
top = this->plateLines->horizontalLines[h1].line;
bottom = this->plateLines->horizontalLines[h2].line;
confidenceDiff += (1.0 - this->plateLines->horizontalLines[h1].confidence);
confidenceDiff += (1.0 - this->plateLines->horizontalLines[h2].confidence);
}
else if (h1 == NO_LINE && h2 != NO_LINE)
{
bottom = this->plateLines->horizontalLines[h2].line;
top = bottom.getParallelLine(idealPixelHeight);
missingSegmentPenalty++;
confidenceDiff += (1.0 - this->plateLines->horizontalLines[h2].confidence);
}
else if (h1 != NO_LINE && h2 == NO_LINE)
{
top = this->plateLines->horizontalLines[h1].line;
bottom = top.getParallelLine(-1 * idealPixelHeight);
missingSegmentPenalty++;
confidenceDiff += (1.0 - this->plateLines->horizontalLines[h1].confidence);
}
scoreKeeper.setScore("SCORING_MISSING_SEGMENT_PENALTY_HORIZONTAL", missingSegmentPenalty, SCORING_MISSING_SEGMENT_PENALTY_HORIZONTAL);
//scoreKeeper.setScore("SCORING_LINE_CONFIDENCE_WEIGHT", confidenceDiff, SCORING_LINE_CONFIDENCE_WEIGHT);
// Make sure that the top and bottom lines are above and below
// the text area
if (tlc.isAboveText(top) < 1 || tlc.isAboveText(bottom) > -1)
return;
// We now have 4 possible lines. Let's put them to the test and score them...
//////////////////////////////////////////////////////////////////////////
// SCORE the shape wrt character position and height relative to position
//////////////////////////////////////////////////////////////////////////
Point topPoint = top.midpoint();
Point botPoint = bottom.closestPointOnSegmentTo(topPoint);
float plateHeightPx = distanceBetweenPoints(topPoint, botPoint);
// Get the height difference
float heightRatio = tlc.charHeight / plateHeightPx;
float idealHeightRatio = (pipelineData->config->charHeightMM / pipelineData->config->plateHeightMM);
float heightRatioDiff = abs(heightRatio - idealHeightRatio);
scoreKeeper.setScore("SCORING_PLATEHEIGHT_WEIGHT", heightRatioDiff, SCORING_PLATEHEIGHT_WEIGHT);
//////////////////////////////////////////////////////////////////////////
// SCORE the middliness of the stuff. We want our top and bottom line to have the characters right towards the middle
//////////////////////////////////////////////////////////////////////////
Point charAreaMidPoint = tlc.centerVerticalLine.midpoint();
Point topLineSpot = top.closestPointOnSegmentTo(charAreaMidPoint);
Point botLineSpot = bottom.closestPointOnSegmentTo(charAreaMidPoint);
float topDistanceFromMiddle = distanceBetweenPoints(topLineSpot, charAreaMidPoint);
float bottomDistanceFromMiddle = distanceBetweenPoints(botLineSpot, charAreaMidPoint);
float idealDistanceFromMiddle = idealPixelHeight / 2;
float middleScore = abs(topDistanceFromMiddle - idealDistanceFromMiddle) / idealDistanceFromMiddle;
middleScore += abs(bottomDistanceFromMiddle - idealDistanceFromMiddle) / idealDistanceFromMiddle;
scoreKeeper.setScore("SCORING_TOP_BOTTOM_SPACE_VS_CHARHEIGHT_WEIGHT", middleScore, SCORING_TOP_BOTTOM_SPACE_VS_CHARHEIGHT_WEIGHT);
//////////////////////////////////////////////////////////////
// SCORE: the shape for angles matching the character region
//////////////////////////////////////////////////////////////
float charanglediff = abs(tlc.charAngle - top.angle) + abs(tlc.charAngle - bottom.angle);
scoreKeeper.setScore("SCORING_ANGLE_MATCHES_LPCHARS_WEIGHT", charanglediff, SCORING_ANGLE_MATCHES_LPCHARS_WEIGHT);
if (pipelineData->config->debugPlateCorners)
{
scoreKeeper.printDebugScores();
Mat debugImg(this->inputImage.size(), this->inputImage.type());
this->inputImage.copyTo(debugImg);
cvtColor(debugImg, debugImg, CV_GRAY2BGR);
line(debugImg, top.p1, top.p2, Scalar(0,0,255), 2);
line(debugImg, bottom.p1, bottom.p2, Scalar(0,0,255), 2);
//drawAndWait(&debugImg);
}
float score = scoreKeeper.getTotal();
if (score < this->bestHorizontalScore)
{
float scorecomponent;
if (pipelineData->config->debugPlateCorners)
{
cout << "Horizontal breakdown Score:" << endl;
scoreKeeper.printDebugScores();
}
this->bestHorizontalScore = score;
bestTop = LineSegment(top.p1.x, top.p1.y, top.p2.x, top.p2.y);
bestBottom = LineSegment(bottom.p1.x, bottom.p1.y, bottom.p2.x, bottom.p2.y);
}
}
#include "catch.hpp"
using namespace std;
using namespace cv;
using namespace alpr;
TEST_CASE( "LineSegment Test", "[2d primitives]" ) {
// Test a flat horizontal line
LineSegment flat_horizontal(1,1, 21,1);
REQUIRE( flat_horizontal.angle == 0 );
REQUIRE( flat_horizontal.slope == 0 );
REQUIRE( flat_horizontal.length == 20 );
REQUIRE( flat_horizontal.midpoint().y == 1 );
REQUIRE( flat_horizontal.midpoint().x == 11 );
REQUIRE( flat_horizontal.getPointAt(11) == 1 );
// Test distance between points calculation
REQUIRE( distanceBetweenPoints(Point(10,10), Point(20,20)) == Approx(14.1421) );
REQUIRE( distanceBetweenPoints(Point(-5,10), Point(20,-12)) == Approx(33.3017) );
int testarray1[] = {1, 2, 3, 3, 4, 5 };
int testarray2[] = {0, 2, -3, 3, -4, 5 };
int *testarray3;
REQUIRE( median(testarray1, 6) == 3 );
REQUIRE( median(testarray2, 6) == 1 );
REQUIRE( median(testarray3, 0) == 0 );
}
// Score a collection of lines as a possible license plate region.
// If any segments are missing, extrapolate the missing pieces
void PlateCorners::scoreHorizontals(int h1, int h2)
{
//if (this->debug)
// cout << "PlateCorners::scorePlate" << endl;
float score = 0; // Lower is better
LineSegment top;
LineSegment bottom;
float charHeightToPlateHeightRatio = config->plateHeightMM / config->charHeightMM;
float idealPixelHeight = this->charHeight * charHeightToPlateHeightRatio;
if (h1 == NO_LINE && h2 == NO_LINE)
{
// return;
Point centerLeft = charRegion->getCharBoxLeft().midpoint();
Point centerRight = charRegion->getCharBoxRight().midpoint();
LineSegment centerLine = LineSegment(centerLeft.x, centerLeft.y, centerRight.x, centerRight.y);
top = centerLine.getParallelLine(idealPixelHeight / 2);
bottom = centerLine.getParallelLine(-1 * idealPixelHeight / 2 );
score += SCORING_MISSING_SEGMENT_PENALTY_HORIZONTAL * 2;
}
else if (h1 != NO_LINE && h2 != NO_LINE)
{
top = this->plateLines->horizontalLines[h1];
bottom = this->plateLines->horizontalLines[h2];
}
else if (h1 == NO_LINE && h2 != NO_LINE)
{
bottom = this->plateLines->horizontalLines[h2];
top = bottom.getParallelLine(idealPixelHeight);
score += SCORING_MISSING_SEGMENT_PENALTY_HORIZONTAL;
}
else if (h1 != NO_LINE && h2 == NO_LINE)
{
top = this->plateLines->horizontalLines[h1];
bottom = top.getParallelLine(-1 * idealPixelHeight);
score += SCORING_MISSING_SEGMENT_PENALTY_HORIZONTAL;
}
// Make sure this line is above our license plate letters
if (top.isPointBelowLine(charRegion->getCharBoxTop().midpoint()) == false)
return;
// Make sure this line is below our license plate letters
if (bottom.isPointBelowLine(charRegion->getCharBoxBottom().midpoint()))
return;
// We now have 4 possible lines. Let's put them to the test and score them...
/////////////////////////////////////////////////////////////////////////
// Score "Boxiness" of the 4 lines. How close is it to a parallelogram?
/////////////////////////////////////////////////////////////////////////
float horizontalAngleDiff = abs(top.angle - bottom.angle);
score += (horizontalAngleDiff) * SCORING_BOXINESS_WEIGHT;
// if (this->debug)
// cout << "PlateCorners boxiness score: " << (horizontalAngleDiff + verticalAngleDiff) * SCORING_BOXINESS_WEIGHT << endl;
//////////////////////////////////////////////////////////////////////////
// SCORE the shape wrt character position and height relative to position
//////////////////////////////////////////////////////////////////////////
Point topPoint = top.midpoint();
Point botPoint = bottom.closestPointOnSegmentTo(topPoint);
float plateHeightPx = distanceBetweenPoints(topPoint, botPoint);
// Get the height difference
float heightRatio = charHeight / plateHeightPx;
float idealHeightRatio = (config->charHeightMM / config->plateHeightMM);
//if (leftRatio < MIN_CHAR_HEIGHT_RATIO || leftRatio > MAX_CHAR_HEIGHT_RATIO || rightRatio < MIN_CHAR_HEIGHT_RATIO || rightRatio > MAX_CHAR_HEIGHT_RATIO)
float heightRatioDiff = abs(heightRatio - idealHeightRatio);
// Ideal ratio == ~.45
// Get the distance from the top and the distance from the bottom
// Take the average distances from the corners of the character region to the top/bottom lines
// float topDistance = distanceBetweenPoints(topMidLinePoint, charRegion->getCharBoxTop().midpoint());
// float bottomDistance = distanceBetweenPoints(bottomMidLinePoint, charRegion->getCharBoxBottom().midpoint());
// float idealTopDistance = charHeight * (TOP_WHITESPACE_HEIGHT_MM / CHARACTER_HEIGHT_MM);
// float idealBottomDistance = charHeight * (BOTTOM_WHITESPACE_HEIGHT_MM / CHARACTER_HEIGHT_MM);
// float distScore = abs(topDistance - idealTopDistance) + abs(bottomDistance - idealBottomDistance);
score += heightRatioDiff * SCORING_PLATEHEIGHT_WEIGHT;
//////////////////////////////////////////////////////////////////////////
// SCORE the middliness of the stuff. We want our top and bottom line to have the characters right towards the middle
//////////////////////////////////////////////////////////////////////////
Point charAreaMidPoint = charRegion->getCharBoxLeft().midpoint();
Point topLineSpot = top.closestPointOnSegmentTo(charAreaMidPoint);
Point botLineSpot = bottom.closestPointOnSegmentTo(charAreaMidPoint);
float topDistanceFromMiddle = distanceBetweenPoints(topLineSpot, charAreaMidPoint);
float bottomDistanceFromMiddle = distanceBetweenPoints(topLineSpot, charAreaMidPoint);
float idealDistanceFromMiddle = idealPixelHeight / 2;
float middleScore = abs(topDistanceFromMiddle - idealDistanceFromMiddle) + abs(bottomDistanceFromMiddle - idealDistanceFromMiddle);
score += middleScore * SCORING_TOP_BOTTOM_SPACE_VS_CHARHEIGHT_WEIGHT;
// if (this->debug)
// {
// cout << "PlateCorners boxiness score: " << avgRatio * SCORING_TOP_BOTTOM_SPACE_VS_CHARHEIGHT_WEIGHT << endl;
// cout << "PlateCorners boxiness score: " << distScore * SCORING_PLATEHEIGHT_WEIGHT << endl;
// }
//////////////////////////////////////////////////////////////
// SCORE: the shape for angles matching the character region
//////////////////////////////////////////////////////////////
float charanglediff = abs(charAngle - top.angle) + abs(charAngle - bottom.angle);
score += charanglediff * SCORING_ANGLE_MATCHES_LPCHARS_WEIGHT;
// if (this->debug)
// cout << "PlateCorners boxiness score: " << charanglediff * SCORING_ANGLE_MATCHES_LPCHARS_WEIGHT << endl;
if (score < this->bestHorizontalScore)
{
float scorecomponent;
if (this->config->debugPlateCorners)
{
cout << "xx xx Score: charHeight " << this->charHeight << endl;
cout << "xx xx Score: idealHeight " << idealPixelHeight << endl;
cout << "xx xx Score: h1,h2= " << h1 << "," << h2 << endl;
cout << "xx xx Score: Top= " << top.str() << endl;
cout << "xx xx Score: Bottom= " << bottom.str() << endl;
cout << "Horizontal breakdown Score:" << endl;
cout << " -- Boxiness Score: " << horizontalAngleDiff << " -- Weight (" << SCORING_BOXINESS_WEIGHT << ")" << endl;
scorecomponent = horizontalAngleDiff * SCORING_BOXINESS_WEIGHT;
cout << " -- -- Score: " << scorecomponent << " = " << scorecomponent / score * 100 << "% of score" << endl;
cout << " -- Height Ratio Diff Score: " << heightRatioDiff << " -- Weight (" << SCORING_PLATEHEIGHT_WEIGHT << ")" << endl;
scorecomponent = heightRatioDiff * SCORING_PLATEHEIGHT_WEIGHT;
cout << " -- -- " << scorecomponent << " = " << scorecomponent / score * 100 << "% of score" << endl;
cout << " -- Distance Score: " << middleScore << " -- Weight (" << SCORING_TOP_BOTTOM_SPACE_VS_CHARHEIGHT_WEIGHT << ")" << endl;
scorecomponent = middleScore * SCORING_TOP_BOTTOM_SPACE_VS_CHARHEIGHT_WEIGHT;
cout << " -- -- Score: " << scorecomponent << " = " << scorecomponent / score * 100 << "% of score" << endl;
cout << " -- Char angle Score: " << charanglediff << " -- Weight (" << SCORING_ANGLE_MATCHES_LPCHARS_WEIGHT << ")" << endl;
scorecomponent = charanglediff * SCORING_ANGLE_MATCHES_LPCHARS_WEIGHT;
cout << " -- -- Score: " << scorecomponent << " = " << scorecomponent / score * 100 << "% of score" << endl;
cout << " -- Score: " << score << endl;
}
this->bestHorizontalScore = score;
bestTop = LineSegment(top.p1.x, top.p1.y, top.p2.x, top.p2.y);
bestBottom = LineSegment(bottom.p1.x, bottom.p1.y, bottom.p2.x, bottom.p2.y);
}
}
