Pregunta en HoughLineTransform me ayudó a empezar con esto.
HoughLineTransform convierte segmentos de línea recta en una matriz de entrada en puntos en una matriz de salida. Los puntos brillantes en la matriz de salida representan un ángulo y la distancia desde el centro de una línea. La matriz de salida representa la línea que contiene el segmento (la información del punto final se pierde en su mayor parte).
En el JSL a continuación, la matriz de entrada es 100x100, un campo de ceros con unos donde están las líneas. La dimensión de la matriz de salida está determinada por los parámetros nAngle y nRadius; las columnas representan el ángulo de la línea y las filas son la distancia desde el centro. El generación se llama a la función para cada cambio de los controladores en el gráfico de la izquierda. Gen vuelve a fabricar el estera matrix (100x100) y llama a transform. Luego, Gen reconstruye un mapa de bits con la salida de la transformación y actualiza la imagen de la derecha. La mayor parte del código es solo un escaparate; la llamada a la transformación está cerca del medio.
mx = [10 10 90 90 20 80]; // starter points
my = [10 90 10 90 10 90];
mat = J( 100, 100, 0 ); // input to hough line transform
New Window( "Hough Line Transform",
H List Box(
radio = Radio Box( {"1", "2", "3"}, gen() ), // sometimes you want to see just one line
Graph Box( // left side is just a GUI to position 3 lines
Frame Size( 400, 400 ),
Y Scale( -10, 110 ),
X Scale( -10, 110 ),
xaxis( Add Ref Line( 50, "Dashed", blue, "", 1 ), showmajorticks( 0 ), showminorticks( 0 ), showlabels( 0 ) ),
xname( "drag the square handles" ),
yaxis( Add Ref Line( 50, "Dashed", blue, "", 1 ), showmajorticks( 0 ), showminorticks( 0 ), showlabels( 0 ) ),
yname( "" ),
// when the 6 handles are moved, they capture their location AND generate results
Handle( mx[1], my[1], mx[1] = clamp( x ); my[1] = clamp( y ); gen(); );
Handle( mx[2], my[2], mx[2] = clamp( x ); my[2] = clamp( y ); gen(); );
Line( mx[1 :: 2], my[1 :: 2] ); // draw the lines in the GUI
text({(mx[1]+mx[2])/2,(my[1]+my[2])/2},char(mod(360+180*atan(my[1]-my[2],mx[1]-mx[2])/pi(),180),4));// label angle
If( radio << get > 1,
Handle( mx[3], my[3], mx[3] = clamp( x ); my[3] = clamp( y ); gen(); );
Handle( mx[4], my[4], mx[4] = clamp( x ); my[4] = clamp( y ); gen(); );
Line( mx[3 :: 4], my[3 :: 4] );
text({(mx[3]+mx[4])/2,(my[3]+my[4])/2},char(mod(360+180*atan(my[3]-my[4],mx[3]-mx[4])/pi(),180),4));// label angle
);
If( radio << get > 2,
Handle( mx[5], my[5], mx[5] = clamp( x ); my[5] = clamp( y ); gen(); );
Handle( mx[6], my[6], mx[6] = clamp( x ); my[6] = clamp( y ); gen(); );
Line( mx[5 :: 6], my[5 :: 6] );
text({(mx[5]+mx[6])/2,(my[5]+my[6])/2},char(mod(360+180*atan(my[5]-my[6],mx[5]-mx[6])/pi(),180),4));// label angle
);
),
// reserve a place to display results
H List Box(
V List Box(
imgholder = Border Box( Left( 5 ), Right( 5 ), top( 5 ), bottom( 5 ), Text Box( "drag handles" ) ),
H Center Box( anglebox = Text Box( "angle" ) )
),
V Center Box( Text Box( "Distance from black line to blue center", < )
),
hcenterbox(textbox("
The blue cross hair and the nearest point on the line (defined by the black line segment) form a distance.
When the blue cross hair is on the line defined by the black segment, the red cross hair is centered vertically (zero distance).
The black segment's slope forms the angle. The displayed angle is for the point identified by the red cross hair, which is on the brightest point.
",<);
// keep the handles in range so the drawline function is happy
clamp = Function( {t},
Max( 1, Min( 99, t ) )
);
//
// the three lines in the gui generate three lines in mat
// then the transform runs on mat and the result updates
//
gen = Function( {},
{xy, r, c},
mat[0, 0] = 0; // reset mat
drawline( mx[1 :: 2], my[1 :: 2] ); // add lines to mat
If( radio << get > 1,
drawline( mx[3 :: 4], my[3 :: 4] )
);
If( radio << get > 2,
drawline( mx[5 :: 6], my[5 :: 6] )
);
// run hough...
result = Hough Line Transform( mat, nangle( 200 ), nradius( 200 ) );// just to make result matrix square
// normalize...
result = result / Max( result );
result = result^.5; // boost brightness
ResultRed = result;
If( 1,//radio << get == 1,
xy = Loc Max( result ); // maximum bright point in transform
r = Floor( (xy - 1) / N Cols( result ) ) + 1;
c = xy - (r - 1) * N Cols( result );
anglebox << settext( "Black line angle "||Char( 180 * c / N Cols( result ), 4 ) || "°" );
ResultRed[r, 0] = .5;
ResultRed[0, c] = .5;
);
// update the results
img = New Image( "rgb", {resultRed, result, result} ); // gray scale bitmap from result
img << scale( 2 ); // bigger
(imgholder << child) << delete; // swap out old
imgholder << append( img ); // for new
);
// taken from scripting index example, a fast drawline in a matrix
drawline = Function( {mx, my},
{dx = mx[2] - mx[1], dy = my[2] - my[1], adx = Abs( dx ), ady = Abs( dy ), m, b},
If( adx > ady,
xx = Round( mx[1] ) :: Round( mx[2] );
m = dy / dx;
b = my[1] - m * mx[1];
yy = Round( xx * m + b );
,
yy = Round( my[1] ) :: Round( my[2] );
m = dx / dy;
b = mx[1] - m * my[1];
xx = Round( yy * m + b );
);
singleindex = (N Row( mat ) - yy) * N Col( mat ) + xx;
Try( mat[singleindex] = 1, 0 ); /* catch indexing errors and ignore the problems */
);
gen(); // do the first round
The JSL creates a GUI to help understand the Hough Line TransformThe JSL creates a GUI to help understand the Hough Line TransformThe JSL creates a GUI to help understand the Hough Line TransformThe JSL creates a GUI to help understand the Hough Line TransformEl JSL crea una GUI para ayudar a comprender la transformación de la línea de Hough
actualización 25 de junio de 2018: comentario de reparación... gen actualiza el bien -imagen de la mano
