11 - PHP Online
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Full code of 11.php
- <?php
- class ImgCompare
- {
- /** @var string $bigSrc */
- protected $bigSrc;
- /** @var array $haystack */
- protected $haystack = [];
- /** @var array $needle */
- protected $needle = [];
- public function __construct(string $bigSrc)
- {
- $this->bigSrc = $bigSrc;
- }
- public function find(string $smallSrc): array
- {
- $big = $this->loadImage($this->bigSrc);
- $small = $this->loadImage($smallSrc);
- $scales = $this->calcScales($big, $small);
- $suitable = [];
- $prevScale = null;
- foreach ($scales as $scale) {
- $haystack = $this->resize($big, $scale);
- $this->loadCache($haystack, $this->haystack);
- imagedestroy($haystack);
- $needle = $this->resize($small, $scale);
- $this->loadCache($needle, $this->needle);
- imagedestroy($needle);
- if ($prevScale !== null) {
- $suitable = $this->expand($suitable, $prevScale / $scale);
- }
- $prevScale = $scale;
- $suitable = $this->compare($suitable);
- $suitable = $this->crop($suitable);
- }
- return $suitable;
- }
- protected function calcScales($big, $small): array
- {
- return [4, 2, 1];
- }
- protected function loadImage($src)
- {
- $img = imagecreatefrompng($src);
- return $img;
- }
- protected function resize($src, int $scale)
- {
- $width = imagesx($src);
- $height = imagesy($src);
- $w = (int) round($width / $scale);
- $h = (int) round($height / $scale);
- $dest = imagecreatetruecolor($w, $h);
- imagecopyresampled($dest, $src, 0, 0, 0, 0, $w, $h, $width, $height);
- return $dest;
- }
- protected function loadCache($img, &$arr)
- {
- $arr = [];
- $w = imagesx($img);
- $h = imagesy($img);
- for ($row = 0; $row < $h; $row++) {
- $arr[$row] = [];
- for ($col = 0; $col < $w; $col++) {
- $arr[$row][$col] = imagecolorat($img, $col, $row);
- }
- }
- }
- protected function compare(array $suitable): array
- {
- $width = count($this->haystack[0]);
- $height = count($this->haystack);
- $w = count($this->needle[0]);
- $h = count($this->needle);
- $arr = [];
- for ($row = 0; $row <= $height - $h; $row++) {
- if (empty($suitable) || isset($suitable[$row])) {
- for ($col = 0; $col <= $width - $w; $col++) {
- if (empty($suitable) || isset($suitable[$row][$col])) {
- $arr[$row][$col] = $this->weight($row, $col);
- }
- }
- }
- }
- return $arr;
- }
- protected function weight(int $row, int $col): int
- {
- $w = count($this->needle[0]);
- $h = count($this->needle);
- $result = 0;
- for ($r = 0; $r < $h; $r++) {
- for ($c = 0; $c < $w; $c++) {
- $result += abs($this->needle[$r][$c] - $this->haystack[$row + $r][$col + $c]);
- }
- }
- return $result;
- }
- protected function crop(array $suitable): array
- {
- $arr = [];
- foreach ($suitable as $row => $cols) {
- foreach ($cols as $col => $weight) {
- $arr["{$row},{$col}"] = $weight;
- }
- }
- asort($arr);
- $arr = array_slice($arr, 0, 25, true);
- $suitable = [];
- foreach ($arr as $entry => $weight) {
- list($row, $col) = explode(",", $entry);
- if (!isset($suitable[$row])) {
- $suitable[$row] = [];
- }
- $suitable[$row][$col] = $weight;
- }
- return $suitable;
- }
- protected function expand(array $suitable, float $scale): array
- {
- $arr = [];
- foreach ($suitable as $row => $cols) {
- $arr[$row * $scale] = [];
- foreach ($cols as $col => $weight) {
- $arr[$row * $scale][$col * $scale] = $weight;
- // + 8 around
- // upper
- if ($row > 0) {
- $arr[$row * $scale - 1][$col * $scale - 1] = $weight;
- $arr[$row * $scale - 1][$col * $scale] = $weight;
- $arr[$row * $scale - 1][$col * $scale + 1] = $weight;
- }
- // left, right
- if ($col > 0) {
- $arr[$row * $scale][$col * $scale - 1] = $weight;
- }
- if ($col < count($cols) - 1) {
- $arr[$row * $scale][$col * $scale + 1] = $weight;
- }
- // bottom
- if ($row < count($suitable) - 1) {
- $arr[$row * $scale + 1][$col * $scale - 1] = $weight;
- $arr[$row * $scale + 1][$col * $scale] = $weight;
- $arr[$row * $scale + 1][$col * $scale + 1] = $weight;
- }
- }
- }
- return $arr;
- }
- }
- //$img = imagecreatetruecolor(200, 150);
- //$gray = imagecolorallocate($img, 150, 150, 150);
- //imagefill($img, 0, 0, $gray);
- //$red = imagecolorallocate($img, 255, 100, 100);
- //// 1
- //imagesetpixel($img, 0, 0, $red);
- //imagesetpixel($img, 1, 0, $red);
- //imagesetpixel($img, 0, 1, $red);
- //imagesetpixel($img, 1, 1, $red);
- //// 2
- //imagesetpixel($img, 20, 30, $red);
- //imagesetpixel($img, 21, 30, $red);
- //imagesetpixel($img, 20, 31, $red);
- //imagesetpixel($img, 21, 31, $red);
- //imagepng($img, __DIR__ . '/big.png');
- //imagedestroy($img);
- //
- //$img = imagecreatetruecolor(8, 11);
- //$gray = imagecolorallocate($img, 150, 150, 150);
- //imagefill($img, 0, 0, $gray);
- //$red = imagecolorallocate($img, 255, 100, 100);
- //imagesetpixel($img, 0, 0, $red);
- //imagesetpixel($img, 1, 0, $red);
- //imagesetpixel($img, 0, 1, $red);
- //imagesetpixel($img, 1, 1, $red);
- //imagepng($img, __DIR__ . '/small.png');
- //imagedestroy($img);
- $start = microtime(true);
- $c = new ImgCompare(__DIR__ . '/big.png');
- $suitable = $c->find(__DIR__ . '/small.png');
- foreach ($suitable as $row => $cols) {
- foreach ($cols as $col => $weight) {
- echo "{$row},{$col} = {$weight}\n";
- }
- }
- $stop = microtime(true);
- echo 'time: ' . round($stop - $start, 4) . ' sec.' . PHP_EOL;
- class Test extends ImgCompare
- {
- public function Test_loadCache()
- {
- $img = imagecreatetruecolor(3, 1);
- $bgColor = imagecolorallocate($img, 255, 255, 255);
- imagefill($img, 0, 0, $bgColor);
- $r = imagecolorallocate($img, 255, 0, 0);
- $g = imagecolorallocate($img, 0, 255, 0);
- $b = imagecolorallocate($img, 0, 0, 255);
- imagesetpixel($img, 0, 0, $r);
- imagesetpixel($img, 1, 0, $g);
- imagesetpixel($img, 2, 0, $b);
- $this->loadCache($img, $this->haystack);
- assert(count($this->haystack) === 1);
- assert(isset($this->haystack[0]));
- assert(count($this->haystack[0]) === 3);
- assert($this->haystack[0][0] === 255 * pow(256, 2) + 0 * pow(256, 1) + 0 * pow(256, 0));
- assert($this->haystack[0][1] === 0 * pow(256, 2) + 255 * pow(256, 1) + 0 * pow(256, 0));
- assert($this->haystack[0][2] === 0 * pow(256, 2) + 0 * pow(256, 1) + 255 * pow(256, 0));
- }
- public function Test_weight()
- {
- $this->haystack = [
- [10, 20, 30],
- [40, 50, 60],
- [70, 80, 90],
- ];
- $this->needle = [
- [100, 20],
- [200, 50],
- ];
- assert($this->weight(0, 0) === abs(100 - 10) + abs(20 - 20) + abs(200 - 40) + abs(50 - 50));
- assert($this->weight(0, 1) === abs(100 - 20) + abs(20 - 30) + abs(200 - 50) + abs(50 - 60));
- assert($this->weight(1, 0) === abs(100 - 40) + abs(20 - 50) + abs(200 - 70) + abs(50 - 80));
- assert($this->weight(1, 1) === abs(100 - 50) + abs(20 - 60) + abs(200 - 80) + abs(50 - 90));
- }
- public function Test_compare()
- {
- $this->haystack = [
- [10, 20, 30],
- [40, 50, 60],
- [70, 80, 90],
- ];
- $this->needle = [
- [100, 20],
- [200, 50],
- ];
- $expected = [
- [$this->weight(0, 0), $this->weight(0, 1)],
- [$this->weight(1, 0), $this->weight(1, 1)],
- ];
- $actual = $this->compare([]);
- assert(
- $expected === $actual,
- 'Expected: ' . var_export($expected, true) . '; actual: ' . var_export($actual, true)
- );
- }
- }
- $test = new Test('');
- $test->Test_loadCache();
- $test->Test_weight();
- $test->Test_compare();