


How to Maintain Image Aspect Ratio When Cropping Images in PHP?
Nov 03, 2024 pm 04:46 PMImage Cropping in PHP
When cropping images in PHP, you may encounter problems, especially when dealing with large images. One workaround is to "shrink the image".
In the given example code, the image is cropped to a fixed size (200x150), which may not fit larger images. To obtain consistent image dimensions before cropping, it is recommended to use the imagecopyresampled() function.
The following formula can be used to generate thumbnails:
$image = imagecreatefromjpeg($_GET['src']); $filename = 'images/cropped_whatever.jpg'; $thumb_width = 200; $thumb_height = 150; $width = imagesx($image); $height = imagesy($image); $original_aspect = $width / $height; $thumb_aspect = $thumb_width / $thumb_height; if ( $original_aspect >= $thumb_aspect ) { // 圖像更寬(縱橫比意義上) $new_height = $thumb_height; $new_width = $width / ($height / $thumb_height); } else { // 縮略圖更寬 $new_width = $thumb_width; $new_height = $height / ($width / $thumb_width); } $thumb = imagecreatetruecolor( $thumb_width, $thumb_height ); // 調(diào)整大小并裁剪 imagecopyresampled($thumb, $image, 0 - ($new_width - $thumb_width) / 2, // 水平居中圖像 0 - ($new_height - $thumb_height) / 2, // 垂直居中圖像 0, 0, $new_width, $new_height, $width, $height); imagejpeg($thumb, $filename, 80);
This code takes the image aspect ratio into account, ensuring that the resized image has the same aspect ratio as the thumbnail size, thus preventing distortion . After resizing and cropping, it will produce a consistently sized image regardless of the original image size.
The above is the detailed content of How to Maintain Image Aspect Ratio When Cropping Images in PHP?. For more information, please follow other related articles on the PHP Chinese website!

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