From: cristy Date: Wed, 30 Apr 2014 10:15:55 +0000 (+0000) Subject: (no commit message) X-Git-Tag: 7.0.1-0~2379 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=ec9a82a7d6938f4ff9993500e150cac3628c0e4b;p=imagemagick --- diff --git a/MagickCore/feature.c b/MagickCore/feature.c index d132298dc..e7e64cfdd 100644 --- a/MagickCore/feature.c +++ b/MagickCore/feature.c @@ -1731,7 +1731,16 @@ MagickExport ChannelFeatures *GetImageFeatures(const Image *image, % % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % -% HoughLineImage() identifies lines in the image. +% Use HoughLineImage() in conjunction with any binary edge extracted image (we +% recommand Canny) to identify lines in the image. The algorithm accumulates +% counts for every white pixel for every possible orientation (for angles from +% 0 to 179 in 1 degree increments) and distance from the center of the image to +% the corner (in 1 px increments) and stores the counts in an accumulator matrix +% of angle vs distance. The size of the accumulator is 180x(diagonal/2). Next +% it searches this space for peaks in counts and converts the locations of the +% peaks to slope and intercept in the normal x,y input image space. Use the +% slope/intercepts to find the endpoints clipped to the bounds of the image. The +% lines are then drawn. The counts are a measure of the length of the lines % % The format of the HoughLineImage method is: %