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Data update

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Ingy döt Net 2026-04-30 12:34:36 -04:00
parent 4bb20c9b71
commit cbaf4c4b64
12390 changed files with 318560 additions and 27248 deletions
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64
Task/Bitmap-Histogram/PHP/bitmap-histogram.php
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@ -1,11 +1,11 @@
define('src_name', 'input.jpg'); // source image
define('dest_name', 'output.jpg'); // destination image
define('src_name', 'input.jpg'); // source image
define('dest_name', 'output.jpg'); // destination image
$img = imagecreatefromjpeg(src_name); // read image
$img = imagecreatefromjpeg(src_name); // read image
if(empty($img)){
echo 'Image could not be loaded!';
exit;
echo 'Image could not be loaded!';
exit;
}
$black = imagecolorallocate($img, 0, 0, 0);
@ -13,42 +13,42 @@ $white = imagecolorallocate($img, 255, 255, 255);
$width = imagesx($img);
$height = imagesy($img);
$array_lum = array(); // for storage of luminosity of each pixel
$sum_lum = 0; // total sum of luminosity
$average_lum = 0; // average luminosity of whole image
$array_lum = array(); // for storage of luminosity of each pixel
$sum_lum = 0; // total sum of luminosity
$average_lum = 0; // average luminosity of whole image
for($x = 0; $x < $width; $x++){
for($y = 0; $y < $height; $y++){
// read pixel value
$color = imagecolorat($img, $x, $y);
$r = ($color >> 16) & 0xFF;
$g = ($color >> 8) & 0xFF;
$b = $color & 0xFF;
// save pixel luminosity in temporary array
$array_lum[$x][$y] = ($r + $g + $b);
// add pixel luminosity to sum
$sum_lum += $array_lum[$x][$y];
}
for($x = 0; $x < $width; $x++){
for($y = 0; $y < $height; $y++){
// read pixel value
$color = imagecolorat($img, $x, $y);
$r = ($color >> 16) & 0xFF;
$g = ($color >> 8) & 0xFF;
$b = $color & 0xFF;
// save pixel luminosity in temporary array
$array_lum[$x][$y] = ($r + $g + $b);
// add pixel luminosity to sum
$sum_lum += $array_lum[$x][$y];
}
}
// calculate average luminosity
$average_lum = $sum_lum / ($width * $height);
for($x = 0; $x < $width; $x++){
for($y = 0; $y < $height; $y++){
// pixel is brighter than average -> set white
// else -> set black
if($array_lum[$x][$y] > $average_lum){
imagesetpixel($img, $x, $y, $white);
}
else{
imagesetpixel($img, $x, $y, $black);
}
}
for($x = 0; $x < $width; $x++){
for($y = 0; $y < $height; $y++){
// pixel is brighter than average -> set white
// else -> set black
if($array_lum[$x][$y] > $average_lum){
imagesetpixel($img, $x, $y, $white);
}
else{
imagesetpixel($img, $x, $y, $black);
}
}
}
// save black and white image to dest_name
imagejpeg($img, dest_name);
if(!file_exists(dest_name)){
echo 'Image not saved! Check permission!';
echo 'Image not saved! Check permission!';
}