A way to determine human and computer bot input is by using CAPTCHA (Acronyn for Completely Automated Public Turing Test to Tell Computers and Humans Apart). This protects against websites where computer bots attempt to infiltrate/hack. They are distorted text which humans can read while computers can't. Here are some samples below:

// ----------------------------------------------------------------- // Name: GENERATE_SVG_CAPTCHA // Description: Generates a captcha SVG picture and // outputs a text for verfication. // // Input Parameters: // $1 (TEXT) - Text // // Output: // $0 (PICTURE) - SVG CAPTCHA picture generated from the Text input // ------------------------------------------------------------------ C_TEXT($input_text;$1) C_LONGINT($i;$j;$k;$len_text) C_PICTURE($0) ARRAY TEXT(asFont;0) If (Count parameters>0)    $input_text:=$1 // input text    $len_text:=((Length($input_text)/2)*50)+25    vID_SVG:=SVG_New ($len_text;(Length($input_text)*15)) // Drawing SVG space    SVG_SET_OPACITY (vID_SVG;100;0) //Set the background to white    FONT LIST(asFont) // loads all the fonts in the system    $j:=0    $k:=20    For ($i;1;Length($input_text))       $textID:=SVG_New_text (vID_SVG;$input_text[[$i]];$j;$k;asFont{(Random%(Size of array(asFont)))+1};(Random%20)+13;-1;-1;"";-1*(Random%20)+0)       $j:=$j+25       $k:=$k+10    End for    SVG EXPORT TO PICTURE(vID_SVG;$0;Copy XML data source) End if

An example of the method call:

C_TEXT($input) C_PICTURE($svg_captcha) $input:="WtZQbxr6" $svg_captcha:=GENERATE_SVG_CAPTCHA ($input)

Sample CAPTCHA picture from the method call (Note: text size, position, and font will change on every call):



See Also:

• CAPTCHA site