質問HoughLineTransform でこれを始めました。
HoughLineTransform は、入力マトリックスの直線セグメントを出力マトリックスのポイントに変換します。 出力マトリックスの明るいスポットは、ラインの中心からの角度と距離を表します。 出力行列は、セグメントを含む行を表します (終点情報はほとんど失われます)。
以下の JSL では、入力行列は 100x100 で、行が 1 でゼロのフィールドです。 出力行列の次元は、nAngle および nRadius パラメータによって決定されます。列は線の角度を表し、行は中心からの距離です。 の世代関数は、左側のグラフのハンドルが変更されるたびに呼び出されます。 ゲンは、マット行列 (100x100) を作成し、変換を呼び出します。 次に、Gen は変換の出力でビットマップを再構築し、右側の画像を更新します。 コードのほとんどは飾りにすぎません。変換への呼び出しは中間付近にあります。
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 TransformJSL は、Hough Line Transform を理解するのに役立つ GUI を作成します。
2018 年 6 月 25 日更新: 修復コメント...gen は、右-手絵
