Ascii art generator w/ color

url2ascii.php

#!/usr/bin/php
<?php

$yscale = 11;
$xscale = 5;
$target_width = get_tty_width();
$inverted = false;

$flags = Array();
$flag_parameters = Array();
$in_parameters = Array();
$params = Array();

for ($i = 1; $i < $argc; $i++) {
    if (preg_match('/^\-([a-z]+)$/', $argv[$i], $matches)) {
        for ($j = 0; $j < strlen($matches[1]); $j++) {
            $letter =$matches[1][$j];
            switch ($letter ){
                case 'c':
                    $flags['cartoon'] = true;
                    #$flag_parameters[] = "cartoon";
                    break;
                case 'o':
                    $flags['open'] = true;
            }
        }
    } else {
        $in_parameters []= $argv[$i];
    }
}

$flag_parameters [] = 'url';

foreach ($flag_parameters as $i => $param) {
    if (! isset($in_parameters[$i])) {
        echo "Parameter Mismatch\n";
        exit;
    }
    $params[$param] = $in_parameters[$i];
}

if (! isset($params['url'])) {
	echo "Please include a URL.\n";
	die (1);
}

$url = $params['url'];

if (preg_match('/imgur\.com\/([^\.]+)$/i', $url)) {
	$url = $url.'.jpg';
}
if (! preg_match('/([a-z]{3,5}):\/\/(.*)/i', $url)) {
	$url = 'http://'.$url;
}

$image = file_get_contents($url);
if (! $image) {
	echo "Could not fetch image $url\n";
	die(1);
}

if (@ $flags['open']) {
    system('open '.$url);
}

$img = imagecreatefromstring($image);



#imagefilter($img, IMG_FILTER_EDGEDETECT);
$image_width = imagesx($img);
$image_height = imagesy($img);

$ascii_w_h_scale = $xscale / $yscale;
$img_scale = $image_width/$image_height;

$target_height = ($target_width * $ascii_w_h_scale) / ($img_scale);

$ascii_x_scale = $image_width / $target_width;
$ascii_y_scale = $image_height / $target_height;

function brightness_from_index($rgb, &$_r, &$_g, &$_b) {
    $r = (($rgb >> 16) & 0xFF);
    $g = (($rgb >> 8) & 0xFF);
    $b = (($rgb) & 0xFF);

    $_r += $r;
    $_g += $b;
    $_b += $b;

    $r /= 256;
    $g /= 256;
    $b /= 256;

    #echo "$r $g $b\n";

    $out = sqrt((0.241*$r*$r) + (0.691*$g*$g) + (0.068*$b*$b));

    #echo "$r $g $b $out\n";

    return $out;
}

function get_tty_width() {
    $output = exec('tput cols');
    return $output;
}

function get_ascii_pixel($img, $x0, $x1, $y0, $y1, $inverted) {
	$total = 0;
    $count = 0;

    $r = $g = $b = 0;

	for ($x = round($x0); $x < round($x1); $x++) {
		for ($y = round($y0); $y < round($y1); $y++) {
            $total += brightness_from_index(imagecolorat($img, $x, $y), $r, $g, $b);
            $count++;
		}
	}

    $r /= $count;
    $g /= $count;
    $b /= $count;

   # print_r(Array($r, $g, $b));

    $colors = Array(
        'a000a0' => '0;35', // purple
        '0000cc' => '0;34', // blue
        '00ff00' => '0;32', // green
        'ff0000' => '0;31', // red
        'ffffff' => '1;37', // white
        'cccccc' => '0;37', // light gray
        //'888888' => '1;30', // dark gray
        'ffff00' => '1;33', // yellow
        '000000' => '0;30', // black
    );

    $diff = INF;
    $out_color = '1;37'; // white

    foreach ($colors as $color => $symbol) {
        $cr = hexdec(substr($color, 0, 2));
        $cg = hexdec(substr($color, 2, 2));
        $cb = hexdec(substr($color, 4, 2));

        $this_diff = sqrt(pow($r - $cr, 2) +
                          pow($g - $cg, 2) +
                          pow($b - $cb, 2));

        if ($this_diff < $diff) {
            $diff = $this_diff;
            $out_color = $symbol;
        }
    }

    $average = (float)$total / (float)$count;

    if (! $inverted) {
    //    $average = 1 - $average;
    }

    static $pixels = Array(
        '0.9' => '#',
        '0.8' => '%',
        '0.7' => 'T',
        '0.6' => '=',
        '0.5' => '+',
        '0.4' => '~',
        '0.3' => '-',
        '0.2' => ',',
        '0.1' => '.',
        '0'   => ' ',
    );

    foreach ($pixels as $prob => $symbol) {
        if ($average >= $prob) {
            return "\033[" . $out_color . "m". $symbol. "\033[0m";
            
        }
    }
}

for ($y = 0; $y < $target_height - 1; $y++) {
	for ($x = 0; $x < $target_width - 1; $x++) {
		echo get_ascii_pixel($img, $x * $ascii_x_scale, ($x+1) * $ascii_x_scale, $y * $ascii_y_scale, ($y + 1) * $ascii_y_scale, $inverted);
	}
	echo "\n";
}