Consider the following image:

A visual inspection leads me to believe that the dominant color is yellow:

However, this color is not among the dominant colors extracted by ColorThief:

At first I thought the bright yellow was misidentified as white-ish and thus discarded. However, in a test case, isNonWhite returns true for (253, 230, 44)...

a sliMpd user reported an error caused by color-thief-php. Unfortunately i was not able to reproduce it but in theory this changes should do the trick!?

Have encountered many memory errors while processing a directory of many files (3188 jpegs total). Memory usage steadily increases when ColorThief::getPalette is called until a large file causes a memory error. Profiling using pecl memprof shows that the most memory usage is occuring within color thief.

On my machine, adding the following appears to have improved the ability for PHP to garbage collect:

• static::getPalette $pixelArray = null;
• static::quantize $histo = null;

See below for placement. Still testing to confirm.

public static function getPalette($sourceImage, $colorCount = 10, $quality = 10, array $area = null)
{
    // short-circuit
    if ($colorCount < 2 || $colorCount > 256) {
        throw new \InvalidArgumentException("The number of palette colors must be between 2 and 256 inclusive.");
    }
    // short-circuit
    if ($quality < 1) {
        throw new \InvalidArgumentException("The quality argument must be an integer greater than one.");
    }

    $pixelArray = static::loadImage($sourceImage, $quality, $area);
    if (!count($pixelArray)) {
        throw new \RuntimeException("Unable to compute the color palette of a blank or transparent image.", 1);
    }

    // Send array to quantize function which clusters values
    // using median cut algorithm
    $cmap = static::quantize($pixelArray, $colorCount);
    $palette = $cmap->palette();

    $pixelArray = null;
    return $palette;
}

private static function quantize($pixels, $maxcolors)
{
    // short-circuit
    if (! count($pixels) || $maxcolors < 2 || $maxcolors > 256) {
        // echo 'wrong number of maxcolors'."\n";
        return false;
    }

    $histo = static::getHisto($pixels);

    // check that we aren't below maxcolors already
    //if (count($histo) <= $maxcolors) {
        // XXX: generate the new colors from the histo and return
    //}

    $vbox = static::vboxFromHistogram($histo);

    $pq = new PQueue(function ($a, $b) {
        return ColorThief::naturalOrder($a->count(), $b->count());
    });
    $pq->push($vbox);

    // first set of colors, sorted by population
    static::quantizeIter($pq, self::FRACT_BY_POPULATIONS * $maxcolors, $histo);

    // Re-sort by the product of pixel occupancy times the size in color space.
    $pq->setComparator(function ($a, $b) {
        return ColorThief::naturalOrder($a->count() * $a->volume(), $b->count() * $b->volume());
    });

    // next set - generate the median cuts using the (npix * vol) sorting.
    static::quantizeIter($pq, $maxcolors - $pq->size(), $histo);

    // calculate the actual colors
    $cmap = new CMap();

    for ($i = $pq->size(); $i > 0; $i--) {
        $cmap->push($pq->pop());
    }
    $histo = null;

    return $cmap;
}

Speeds things up considerably and uses quite a bit less memory when testing the vegetables_1500x995.png test image.

Basic Symfony stopwatch testing says this is faster than the javascript version. While I hesitate to compare numbers since the hardware and OS is different between my laptop and my dev server, it is much improved. I think the original timing was around 1000ms. The javascript version gets about 490ms on their drag-and-drop demo and this is now getting around 110ms when timing ColorThief::getPalette($thiefImage, 10, 10) which I think is a fair comparison at comparing a quality of every 10 pixels. Using a quality of 1 pixel and timing ColorThief::getPalette($thiefImage, 10, 1) averages about 520ms.

Memory usage is also drastically improved with stopwatch reporting 2MB and the symfony dev toolbar shows the page using 8MB. I think this was over 20MB previously.

first of all: thank you for this lib!
i experienced a freezing in one of my applictions when calling \ColorThief\ColorThief::getColor($absolutePath, $quality)
after some debugging i found out that ColorThief did never exit a while loop
this fixed the issue for me

--- ksubileau/color-thief-php/src/ColorThief/ColorThief.php     2022-08-21 17:16:32.600014736 +0200
+++ "ksubileau/color-thief-php/src/ColorThief/ColorThief copy.php"      2022-08-21 17:14:31.940025874 +0200
@@ -448,6 +448,7 @@
         $nIterations = 0;
 
         while ($nIterations < self::MAX_ITERATIONS) {
+            ++$nIterations;
             if ($nColors >= $target) {
                 return;
             }
@@ -460,7 +461,6 @@
 
             if (!$vBox->count()) { /* just put it back */
                 $priorityQueue->push($vBox);
-                ++$nIterations;
                 continue;
             }
             // do the cut

EDIT
i did not try to reproduce this in a vanilla scenario but the problematic file seems to be this one (extracted from id3 tags)

It doesn't save memory to use fewer bits since they're stored as integers anyway. Zero the least significant bits (keep 5 most significant bits) for everything other than pixelArray. I found it confusing to get the original color back where you needed to know to shift things by the least significant bits dropped.

This way you decide how many significant bits to keep when calling getColorIndex and don't need to remember when you want the colors back via getColorsFromIndex.

Hi, I'm getting a crash when getting the color of an pure white image

I've tried other solid colors and had no seen any problems so far.

The test image is here

Fatal error: Call to a member function palette() on a non-object in .../color-thief-php/ColorThiefPHP.php on line 380

Call Stack:
    0.0002     331608   1. {main}() .../color_dominant_cron.php:0
    0.0055     707948   2. ColorThiefPHP::getColor() .../color_dominant_cron.php:20
    0.0055     708036   3. ColorThiefPHP::getPalette() .../color-thief-php/ColorThiefPHP.php:288

Currently, it seems unfortunately that the Javascript version is quite a lot faster and more efficient than this PHP port.

As I'm not a PHP optimization specialist, any proposal (comment or pull request) in order to improve performance (memory consumption and/or computation time) is welcomed !

An image that fits in a single histogram bucket (single color image) causes VBox->volume to be invalid and negative (instead of 1) due to not setting rgbMax in addition to rgbMax. This leaves rgbMax at 0 causing VBox to compute a negative and incorrect volume when calculated as $this->volume = (($this->r2 - $this->r1 + 1) * ($this->g2 - $this->g1 + 1) * ($this->b2 - $this->b1 + 1));

Hi Devs,

I would like to use Color-Thief to analyse image colors. My pictures are based on remote CDN(s) furthermore a few of them are protected. So I can't reach them with getImageSize. I am able to grab them with CURL, but I don't want to copy-paste them.

It would be nice if I can load images from binary string.

It's hard to extend the whole codebase, because ImageLoader functions are protected and hardcoded into the logic.

What do you think?

Hi,

Sorry for the noob question, but how i can use this class in my project? i did create an php file and added these lines in to it:

require_once 'ColorThief.php';

$sourceImage = '1.jpg';

use ColorThief\ColorThief;
$palette = ColorThief::getPalette($sourceImage, 8);

then i got this error:

Fatal error: Class 'ColorThief\Image\ImageLoader' not found in C:\UwAmp\www\ColorThief\ColorThief.php on line 182
--


1 | 0.0013 | 133520 | {main}( ) | ...\show.php:0
2 | 0.0033 | 198184 | ColorThief\ColorThief::getPalette( ) | ...\show.php:8
3 | 0.0033 | 198392 | ColorThief\ColorThief::loadImage( ) | ...\ColorThief.php:140

Could you please help me to get this fixed?

Our hosting provider scans their servers for known exploits from time to time. warned us about a know exploit and blocked access to the following file within color-thief-php:

src/ColorThief/Image/Adapter/AbstractAdapter.php

The reason given is

# Known exploit = [Fingerprint Match (fp)] [PHP Exploit [P2128]]

Did anyone else noticed this as well? Anything we can do? Or can this be updated/fixed in the lib?

Cheers.

Current implementation disregards all the colors that are rgb(250, 250, 250) or brighter (see THRESHOLD_WHITE variable).

This can be useful for some users. Let's say you want to get a dominant color of a dress for an online shop and all the pictures are on white background.

But why this is default behaviour? Why this can't be changed? Why there's nothing about it in the description?

I wish by default all the bright colors also would be considered by algorithm, but user can explicitly add a parameter like $threshhold_white to exclude them.

Feature: Add libvips support for image processing. https://github.com/libvips/libvips https://github.com/libvips/php-vips

It would be convenient, because now I have to use GD or Imagick to work with Color Thief PHP, while the rest of the processing is done by the libvips.

• PHP: 7.3
• OS: Comparing MacOS vs Ubuntu Docker Image

Given this image:

I'm getting different colours between running locally and in our testing environment.

On my Mac, the colours I get are:

• #8B849F
• #273647
• #EBB6B4
• #4E3C3E
• #987132

Whereas on our testing environment (which is a Ubuntu Docker image, running from CircleCI) I get:

• #F7ACB3
• #9AA7C7
• #B9752E
• #FDD58D
• #353A71

If we visualise these colours, we can see that they look okay. On the right, I've ordered colours to where they're most similar.

What would be the reason for seeing different colours?

Update file CMap.php:28

public function palette() {

$total = array_sum($this->vboxes->map(function ($x) {
    return $x['vbox']->count();
}));

return $this->vboxes->map(function ($vb) use ($total) {
    return array($vb['color'], intval($vb['vbox']->count() / floatval($total) * 100));
});

}

Would it be possible to get some sort of dominance percentage for each color returned in the palette, so I can choose the second most dominant color for example?