try to improve color guessing algorithm a bit

[tt-rss.git] / include / colors.php

diff --git a/include/colors.php b/include/colors.php
index d1e970728a272c152d9b8da746b615948775b6d3..19c8915177473b3cdc007f02d29a6e5014d1f75d 100644 (file)
--- a/include/colors.php
+++ b/include/colors.php
@@ -1,5 +1,7 @@
 <?php
 
+require_once "lib/floIcon.php";
+
 function _resolve_htmlcolor($color) {
        $htmlcolors = array ("aliceblue" => "#f0f8ff",
                "antiquewhite" => "#faebd7",
@@ -278,4 +280,62 @@ function hsl2rgb($arr) {
     return array($r, $g, $B);
 }
 
+       function colorPalette($imageFile, $numColors, $granularity = 5) {
+          $granularity = max(1, abs((int)$granularity));
+          $colors = array();
+
+               $size = @getimagesize($imageFile);
+
+               if (strtolower($size['mime']) == 'image/vnd.microsoft.icon') {
+                       $ico = new floIcon();
+                       @$ico->readICO($imageFile);
+
+                       if(count($ico->images)==0)
+                               return null;
+                       else
+                               $img = @$ico->images[count($ico->images)-1]->getImageResource();
+
+               } else {
+                  $img = @imagecreatefromstring(file_get_contents($imageFile));
+               }
+
+               if (!$img) return false;
+
+          for($x = 0; $x < $size[0]; $x += $granularity) {
+             for($y = 0; $y < $size[1]; $y += $granularity) {
+                $thisColor = imagecolorat($img, $x, $y);
+                $rgb = imagecolorsforindex($img, $thisColor);
+                $red = round(round(($rgb['red'] / 0x33)) * 0x33);
+                $green = round(round(($rgb['green'] / 0x33)) * 0x33);
+                $blue = round(round(($rgb['blue'] / 0x33)) * 0x33);
+                $thisRGB = sprintf('%02X%02X%02X', $red, $green, $blue);
+                if(array_key_exists($thisRGB, $colors)) {
+                   $colors[$thisRGB]++;
+                } else{
+                   $colors[$thisRGB] = 1;
+                }
+             }
+               }
+
+          arsort($colors);
+          return array_slice(array_keys($colors), 0, $numColors);
+       }
+
+       function calculate_avg_color($iconFile) {
+               $palette = colorPalette($iconFile, 4, 4);
+
+               if (is_array($palette)) {
+                       foreach ($palette as $p) {
+                               $hsl = rgb2hsl(_color_unpack("#$p"));
+
+                               if ($hsl[1] > 0.25 && $hsl[2] > 0.25 &&
+                                       !($hsl[0] >= 0 && $hsl[0] < 0.01 && $hsl[1] < 0.01) &&
+                                       !($hsl[0] >= 0 && $hsl[0] < 0.01 && $hsl[2] > 0.99)) {
+
+                                       return _color_pack(hsl2rgb($hsl));
+                               }
+                       }
+               }
+               return false;
+       }
 ?>