|
|
 |
hexdec (PHP 3, PHP 4, PHP 5) hexdec -- Hexadecimal to decimal Descriptionnumber hexdec ( string hex_string )
Returns the decimal equivalent of the hexadecimal number
represented by the hex_string argument.
hexdec() converts a hexadecimal string to a
decimal number. The largest number that can be converted is
7fffffff or 2147483647 in decimal.
As of PHP 4.1.0, this function can also convert larger numbers. It returns
float in that case.
hexdec() will ignore any non-hexadecimal
characters it encounters.
Пример 1. hexdec() example |
<?php
var_dump(hexdec("See"));
var_dump(hexdec("ee"));
var_dump(hexdec("that")); var_dump(hexdec("a0")); ?>
|
|
See also dechex(),
bindec(),
octdec() and
base_convert().
hexdec
repley at freemail dot it
28-May-2006 06:55
From color to color to ...... to color with fade effect. Good for dynamic bar chart.
<?php
function MultiColorFade($hex_array, $steps) {
$tot = count($hex_array);
$gradient = array();
$fixend = 2;
$passages = $tot-1;
$stepsforpassage = floor($steps/$passages);
$stepsremain = $steps - ($stepsforpassage*$passages);
for($pointer = 0; $pointer < $tot-1 ; $pointer++) {
$hexstart = $hex_array[$pointer];
$hexend = $hex_array[$pointer + 1];
if($stepsremain > 0){
if($stepsremain--){
$stepsforthis = $stepsforpassage + 1;
}
}else{
$stepsforthis = $stepsforpassage;
}
if($pointer > 0){
$fixend = 1;
}
$start['r'] = hexdec(substr($hexstart, 0, 2));
$start['g'] = hexdec(substr($hexstart, 2, 2));
$start['b'] = hexdec(substr($hexstart, 4, 2));
$end['r'] = hexdec(substr($hexend, 0, 2));
$end['g'] = hexdec(substr($hexend, 2, 2));
$end['b'] = hexdec(substr($hexend, 4, 2));
$step['r'] = ($start['r'] - $end['r']) / ($stepsforthis);
$step['g'] = ($start['g'] - $end['g']) / ($stepsforthis);
$step['b'] = ($start['b'] - $end['b']) / ($stepsforthis);
for($i = 0; $i <= $stepsforthis-$fixend; $i++) {
$rgb['r'] = floor($start['r'] - ($step['r'] * $i));
$rgb['g'] = floor($start['g'] - ($step['g'] * $i));
$rgb['b'] = floor($start['b'] - ($step['b'] * $i));
$hex['r'] = sprintf('%02x', ($rgb['r']));
$hex['g'] = sprintf('%02x', ($rgb['g']));
$hex['b'] = sprintf('%02x', ($rgb['b']));
$gradient[] = strtoupper(implode(NULL, $hex));
}
}
$gradient[] = $hex_array[$tot-1];
return $gradient;
}
$multi_hex_array = array();
$multi_hex_array[] = array('FF0000','FFFF00');
$multi_hex_array[] = array('FF0000','FFFF00','00FF00');
$multi_hex_array[] = array('FF0000','FFFF00','00FF00','00FFFF');
$multi_hex_array[] = array('FF0000','FFFF00','00FF00','00FFFF','0000FF');
$multi_hex_array[] = array('FF0000','FFFF00','00FF00','00FFFF','0000FF','000000');
$multi_hex_array[] = array('FF0000','FFFF00','00FF00','00FFFF','0000FF','000000','FFFFFF');
foreach($multi_hex_array as $hex_array){
$totcolors = count($hex_array);
$steps = 44;
$a = MultiColorFade($hex_array, $steps);
$tot = count($a);
$table = '<table border=1 width="300">' . "\n";
for ($i = 0; $i < $tot; $i++){
$table .= ' <tr><td bgcolor="' . $a[$i] . '">' . ($i+1) .'</td><td><pre>' . $a[$i] . '</pre></td></tr>' . "\n";
}
$table .= '</table><br /><br />';
echo '<br />Demanded steps = ' . $steps . '<br />';
echo 'Returned steps = ' . $tot;
if($steps == $tot){
echo '<br />OK.' . $steps . ' = ' . $tot . '<br />';
}else{
echo '<br /><span style="color:#FF0000">FAILED! Demanded steps and returned steps are NOT equal!: ' . $steps . ' != ' . $tot . '</span><br />';
}
echo $table;
}
?>
Repley.
greatwhitepine at NOSPAM dot yahoo dot ca
30-Mar-2006 12:46
Hex to binary conversion that works for large and small hex numbers.
<?php
function hexbin($str_hex) {
$str_bin = FALSE;
for ($i=0; $i < strlen($str_hex); $i++) {
$str_bin .= sprintf("%04s", decbin(hexdec($str_hex[$i])));
}
return $str_bin;
}
$str_hex = "effffff20df";
print "\n HEX VALUE: $str_hex\n";
printf(" REAL BINARY VALUE: %50s\n", hexbin($str_hex));
printf("CHOPPED BINARY VALUE: %50s\n\n", decbin(hexdec($str_hex)));
?>
ayadav at infoprocorp dot com
28-Dec-2005 12:03
From Amit Yadav
Hex to binary conversion
$num = hexdec("20DF");
echo binfromdec($num);
function binfromdec($num)
{
if ($num > 32766) return ("Too Large!");
if ($num & 16384) $bit15 = 1;
if ($num & 8192) $bit14 = 1;
if ($num & 4096) $bit13 = 1;
if ($num & 2048) $bit12 = 1;
if ($num & 1024) $bit11 = 1;
if ($num & 512) $bit10 = 1;
if ($num & 256) $bit9 = 1;
if ($num & 128) $bit8 = 1;
if ($num & 64) $bit7 = 1;
if ($num & 32) $bit6 = 1;
if ($num & 16) $bit5 = 1;
if ($num & 8) $bit4 = 1;
if ($num & 4) $bit3 = 1;
if ($num & 2) $bit2 = 1;
if ($num & 1) $bit1 = 1;
return ("" . $bit15 . $bit14 . $bit13 . $bit12 . $bit11 . $bit10 . $bit9 . $bit8 . $bit7 . $bit6 . $bit5 . $bit4 . $bit3 . $bit2 . $bit1);
}
cory at lavacube dot com
28-Oct-2005 01:59
A handy little function to convert HEX colour codes to "web safe" colours...
<?php
function color_mkwebsafe ( $in )
{
$vals['r'] = hexdec( substr($in, 0, 2) );
$vals['g'] = hexdec( substr($in, 2, 2) );
$vals['b'] = hexdec( substr($in, 4, 2) );
foreach( $vals as $val )
{
$val = ( round($val/51) * 51 );
$out .= str_pad(dechex($val), 2, '0', STR_PAD_LEFT);
}
return $out;
}
?>
Example: color_mkwebsafe('0e5c94');
Produces: 006699
Hope this helps someone out... Happy coding. :-)
hajamie@home
24-Oct-2005 07:38
This function will take a hex $color, e.g. fa34bc and make it the shade you want, e.g. anywhere between 0 and 255. The smaller the number, the darker the output color. It keeps the color the same, only changing the shade.
function correctshade($color, $shade)
{
$r = hexdec(substr($color,0,2));
$g = hexdec(substr($color,2,2));
$b = hexdec(substr($color,4,2));
$sum = ($r + $g + $b);
$x = (($shade * 3) - $sum) / $sum;
if ($x >= 0) {
$x = $x + 1;
} else {
$x = 1 + $x;
}
$r = intval($x * $r);
$g = intval($x * $g);
$b = intval($x * $b);
$r = dechex($r);
$g = dechex($g);
$b = dechex($b);
return $r.$g.$b;
}
08-Oct-2005 10:53
I needed to get the opposite colors so my website would be soft on the eyes.
<?php
function OppositeHex($color)
{
$r = dechex(255 - hexdec(substr($color,0,2)));
$r = (strlen($r) > 1) ? $r : '0'.$r;
$g = dechex(255 - hexdec(substr($color,2,2)));
$g = (strlen($g) > 1) ? $g : '0'.$g;
$b = dechex(255 - hexdec(substr($color,4,2)));
$b = (strlen($b) > 1) ? $b : '0'.$b;
return $r.$g.$b;
}
$color = '000000';
echo 'The opposite of #'.$color.' is #'.OppositeHex($color).';
?>
detrate at hotmail dot com
29-Sep-2005 06:38
I made this for a little phpbb mod. It was used to take the hex value from the database and make a color 20 (in decimal) less, resulting a darker color.
EXAMPLE: #336699 to #1f5285
<?php
$row1 = "336699"; $c = 20; $rgb = array(substr($row1,0,2), substr($row1,2,2), substr($row1,4,2));
for($i=0; $i < 3; $i++)
{
if((hexdec($rgb[$i])-$c) >= 0)
{
$rgb[$i] = hexdec($rgb[$i])-$c;
$rgb[$i] = dechex($rgb[$i]);
if(hexdec($rgb[0]) <= 9)
$rgb[$i] = "0".$rgb[$i];
} else {
$rgb[$i] = "00";
}
}
$row2 = $rgb[0].$rgb[1].$rgb[2];
?>
Gabriel Reguly
16-Aug-2005 11:24
After esnhexdec from "rledger at gmail dot com", the esndechex:
<?php
function esndechex($dec){
$a = strtoupper(dechex(substr($dec, 1, 2)));
$b = strtoupper(dechex(substr($dec, 3, 10)));
return $a . $b;
}
?>
djneoform at gmail dot com
20-Jun-2005 09:51
since i couldn't find one, here's an HEX to ASCII converter..
(takes HEX strings (in ASCII) and converts each two digit HEX code into it's ASCII equivalent)
function hex2ascii($str)
{
$p = '';
for ($i=0; $i < strlen($str); $i=$i+2)
{
$p .= chr(hexdec(substr($str, $i, 2)));
}
return $p;
}
bishop
04-Jun-2005 07:51
Bullet-proof hex-to-rgb colour converter like brian at sagesport dot com wanted, just far fewer code lines. As a bonus, gives you the ability to return as string or array:
<?php
function &hex2rgb($hex, $asString = true)
{
if (0 === strpos($hex, '#')) {
$hex = substr($hex, 1);
} else if (0 === strpos($hex, '&H')) {
$hex = substr($hex, 2);
}
$cutpoint = ceil(strlen($hex) / 2)-1;
$rgb = explode(':', wordwrap($hex, $cutpoint, ':', $cutpoint), 3);
$rgb[0] = (isset($rgb[0]) ? hexdec($rgb[0]) : 0);
$rgb[1] = (isset($rgb[1]) ? hexdec($rgb[1]) : 0);
$rgb[2] = (isset($rgb[2]) ? hexdec($rgb[2]) : 0);
return ($asString ? "{$rgb[0]} {$rgb[1]} {$rgb[2]}" : $rgb);
}
?>
Handles 2, 3, and 6 character colour codes with leading # or &H.
Joey Morwick
02-May-2005 01:07
I found it helpful to have the inverse / reverse of this function laying around, since I wanted to insert some binary data into an xmlrpc call (it currently craps out when you do that), and I couldn't find one laying around, so here's a simple little function to do that:
function hex2bin($str) {
$build = '';
while(strlen($str) > 1) {
$build .= chr(hexdec(substr($str, 0, 2)));
$str = substr($str, 2, strlen($str)-2);
}
return $build;
}
rledger at gmail dot com
28-Mar-2005 11:59
To convert a cellular ESN from hexadecimal to decimal, use the following code. The base conversion is different due to the fact that the first two characters of a hexadecimal value must be converted seperately from the remaining six characters.
<?
function esnhexdec($hex){
$a = sprintf("%03d", hexdec(substr($hex, 0, 2)));
$b = sprintf("%08d", hexdec(substr($hex, 2, 6)));
return $a . $b;
}
?>
zubfatal, root at it dot dk
25-Mar-2005 02:36
This replaces my previous class.
I've added a few more input checks in the rgb2hex function.
Also it returned incorrect hex values for 1-digit values.
color::rgb2hex(array(0,0,0)) would output 000 not 00000.
<?php
class color {
function hex2rgb($hexVal = "") {
$hexVal = eregi_replace("[^a-fA-F0-9]", "", $hexVal);
if (strlen($hexVal) != 6) { return "ERR: Incorrect colorcode, expecting 6 chars (a-f, 0-9)"; }
$arrTmp = explode(" ", chunk_split($hexVal, 2, " "));
$arrTmp = array_map("hexdec", $arrTmp);
return array("red" => $arrTmp[0], "green" => $arrTmp[1], "blue" => $arrTmp[2]);
}
function rgb2hex($arrColors = null) {
if (!is_array($arrColors)) { return "ERR: Invalid input, expecting an array of colors"; }
if (count($arrColors) < 3) { return "ERR: Invalid input, array too small (3)"; }
array_splice($arrColors, 3);
for ($x = 0; $x < count($arrColors); $x++) {
if (strlen($arrColors[$x]) < 1) {
return "ERR: One or more empty values found, expecting array with 3 values";
}
elseif (eregi("[^0-9]", $arrColors[$x])) {
return "ERR: One or more non-numeric values found.";
}
else {
if ((intval($arrColors[$x]) < 0) || (intval($arrColors[$x]) > 255)) {
return "ERR: Range mismatch in one or more values (0-255)";
}
else {
$arrColors[$x] = strtoupper(str_pad(dechex($arrColors[$x]), 2, 0, STR_PAD_LEFT));
}
}
}
return implode("", $arrColors);
}
}
?>
brian at sagesport dot com
22-Mar-2005 09:08
The issue I've seen with the existing hex to dec conversion routines is the lack of error-trapping. I stick to the theory that one should try to cover ALL the bases when writing a generalized routine such as this one. I have a varied background that covers a wide variety of design/development languages, on the web as well as desktop apps. As such I've seen multiple formats for writing hex colors.
For example, the color red COULD be written as follows:
#ff0000
&Hff0000
#ff
&Hff
Therefore I have written a function that is case-insensitive and takes into account the chance that different developers have a tendency to format hex colors in different ways.
<?php
function convert_color($hex){
$len = strlen($hex);
$chars = array("#","&","H","h");
$hex = strip_chars($hex, $chars);
preg_match("/([0-9]|[A-F]|[a-f]){".$len."}/i",$hex,$arr);
$hex = $arr[0];
if ($hex) {
switch($len) {
case 2:
$red = hexdec($hex);
$green = 0;
$blue = 0;
break;
case 4:
$red = hexdec(substr($hex,0,2));
$green=hexdec(substr($hex,2,2));
$blue = 0;
break;
case 6:
$red = hexdec(substr($hex,0,2));
$green=hexdec(substr($hex,2,2));
$blue = hexdec(substr($hex,4,2));
break;
};
$color[success] = true;
$color[r] = $red;
$color[g] = $green;
$color[b] = $blue;
return $color;
} else {
$color[success] = false;
$color[error] = "unable to convert hex to dec";
};
}
function strip_chars($string, $char){
$len = strlen($string);
$count = count($char);
if ($count >= 2) {
for ($i=0;$i<=$count;$i++) {
if ($char[$i]) {
$found = stristr($string,$char[$i]);
if ($found) {
$val = substr($string,$found+1,$len-1);
$string = $val;
};
};
};
} else {
$found = stristr($string,$char);
if ($found) {
$val = substr($string,$found+1,$len-1);
};
};
echo $val;
return $val;
}
?>
As you can see, the function "convert_color" accepts a hex # in most acceptable formats and returns an associative array. [success] is set to TRUE if the function succeeds and FALSE if not. The array members [r], [g] and [b] hold the red,green and blue values respectively. If it fails, [error] holds a custom error message.
"strip_chars" is a support function written to remove the unwanted characters from the hex string, and sends the concatenated string back to the calling function. It will accept either a single value or an array of values for the characters to remove.
groobo
10-Feb-2005 11:46
It's just a revision to marfastic's ligten_up script, it simply adds/subtracts mod_color to orig_color.
I use it often to adjust tonals rather than brightness only
<?
function mod_color($orig_color, $mod, $mod_color){
preg_match("/([0-9]|[A-F]){6}/i",$orig_color,$orig_arr);
preg_match("/([0-9]|[A-F]){6}/i",$mod_color,$mod_arr);
if ($orig_arr[0] && $mod_arr[0]) {
for ($i=0; $i<6; $i=$i+2) {
$orig_x = substr($orig_arr[0],$i,2);
$mod_x = substr($mod_arr[0],$i,2);
if ($mod == '+') { $new_x = hexdec($orig_x) + hexdec($mod_x); }
else { $new_x = hexdec($orig_x) - hexdec($mod_x); }
if ($new_x < 0) { $new_x = 0; }
else if ($new_x > 255) { $new_x = 255; };
$new_x = dechex($new_x);
$ret .= $new_x;
}
return $ret;
} else { return false; }
}
?>
19-Jan-2005 09:33
I wondered long time what is the best way to generate RGB-color from HEX-color, and just now i found the simpliest way!
<?php
$hex = "FF00FF";
$rgb = hexdec($hex); ?>
I hope this will save your time! :)
marfastic
10-Dec-2004 07:14
Here is a function to brighten up any color:
function lighten_up($orig_color, $fraction_denom){
// return the color between the color and white
// based on the fraction denom that is passed
if(!isset($fraction_denom))
$fraction_denom = 2;
$highest_val = hexdec("FF");
$r = hexdec(substr($orig_color,0,2));
$r = ($highest_val-$r)/$fraction_denom + $r;
$g = hexdec(substr($orig_color,2,2));
$g = ($highest_val-$g)/$fraction_denom + $g;
$b = hexdec(substr($orig_color,4,2));
$b = ($highest_val-$b)/$fraction_denom + $b;
return dechex($r) . dechex($g) . dechex($b);
}
_meto ALT+q web.de
08-May-2004 09:00
Damn, this took me some real long time! Maybe it's helpfull for those who even have no idea of color-Schemes like me ;)
If u want to generate PDF's for Print Offices u need to set all the colors in CMYK.
Here is a Function that will convert RGB to CMYK
<?
function hex2rgb($hex) {
$color = str_replace('#','',$hex);
$rgb = array('r' => hexdec(substr($color,0,2)),
'g' => hexdec(substr($color,2,2)),
'b' => hexdec(substr($color,4,2)));
return $rgb;
}
function rgb2cmyk($var1,$g=0,$b=0) {
if(is_array($var1)) {
$r = $var1['r'];
$g = $var1['g'];
$b = $var1['b'];
}
else $r=$var1;
$cyan = 255 - $r;
$magenta = 255 - $g;
$yellow = 255 - $b;
$black = min($cyan, $magenta, $yellow);
$cyan = @(($cyan - $black) / (255 - $black)) * 255;
$magenta = @(($magenta - $black) / (255 - $black)) * 255;
$yellow = @(($yellow - $black) / (255 - $black)) * 255;
return array('c' => $cyan / 255,
'm' => $magenta / 255,
'y' => $yellow / 255,
'k' => $black / 255);
}
$color=rgb2cmyk(hex2rgb('#FF0000'));
pdf_setcolor($pdf, "both", "cmyk", $color['c'], $color['m'], $color['y'], $color['k']);
?>
U can call it with parameters (r,g,b) or just with an array(r,g,b) that contains these values.
Hope it works correct. All testing was fine.
gelado at ip3 dot com
29-Aug-2003 04:30
Another hex to decimal converter, up to the precision of PHP floats.
function longhex($hex)
{
$dec = 0;
$bitval = 1;
for($pos = 1; $pos <= strlen($hex); $pos++) {
$dec += hexdec(substr($hex, -$pos, 1)) * $bitval;
$bitval *= 16;
}
return($dec);
}
henrique at recidive dot com
27-May-2003 03:43
Function to convert a string with hexadecimal colors to an associative array with RGB values:
<?
function hex2dec($hex) {
$color = str_replace('#', '', $hex);
$ret = array(
'r' => hexdec(substr($color, 0, 2)),
'g' => hexdec(substr($color, 2, 2)),
'b' => hexdec(substr($color, 4, 2))
);
return $ret;
}
?>
Thanks !
Henrique Recidive
andreas.schmeiler
05-Feb-2003 05:59
Here's another hex2bin variant, works pretty well to me.
function hex2bin($hexdata) {
for ($i=0;$i<strlen($hexdata);$i+=2) {
$bindata.=chr(hexdec(substr($hexdata,$i,2)));
}
return $bindata;
}
chrism at four dot net
15-Dec-2001 10:02
hexdec from 4.1.0 onwards does not show
the same size limitation and therefore
works differently with large numbers than previous php versions.
To obtain the same results, use:
(int) hexdec (...)
andychase at yahoo dot com
17-Jan-2001 06:32
For hex numbers larger than 7FFFFFFF (E.G. PalmOS dates in seconds elapsed since 01/01/1904), I came up with this:
function bighexdec($hexnumber){
$numlength = strlen($hexnumber);
$decnumber = 0;
for($x = 1; $x <= $numlength; $x++){
$place = $numlength - $x;
$operand = hexdec(substr($hexnumber,$place,1));
$exponent = pow(16,$x-1);
$decValue = $operand * $exponent;
$decnumber += $decValue;
}
return $decnumber;
}
joe at aigraphics dot com
20-Oct-2000 03:32
Here is a fast block of code to convert HTML Style HEX colors to RGB:
--------------------
$r = hexdec(substr($color, 0, 2));
$g = hexdec(substr($color, 2, 2));
$b = hexdec(substr($color, 4, 2));
--------------------
hope it helps you, enjoy.
| |
getrandmax