如何使用 PHP 在下面的代码中设置宽高比

Question

我尝试了 2 个实现，如下所示。两者都工作得很好，但当我尝试混合它们时，它不再工作了。$output['status']=FALSE;set_time_limit(0);$allowedImageType = array("image/gif",   "image/jpeg",   "image/pjpeg",   "image/png",   "image/x-png"  );if ($_FILES['image_file_input']["error"] > 0) {    $output['error']= "File Error";}elseif (!in_array($_FILES['image_file_input']["type"], $allowedImageType)) {    $output['error']= "Invalid image format";}elseif (round($_FILES['image_file_input']["size"] / 1024) > 4096) {    $output['error']= "Maximum file upload size is exceeded";} else {    $temp_path = $_FILES['image_file_input']['tmp_name'];    $file = pathinfo($_FILES['image_file_input']['name']);    $fileType = $file["extension"];    $photo_name = $productname.'-'.$member_id."_".time();    $fileName1 = $photo_name . '-125x125' . ".jpg";    $fileName2 = $photo_name . '-250x250' . ".jpg";    $fileName3 = $photo_name . '-500x500' . ".jpg";        $small_thumbnail_path = "uploads/large/";    createFolder($small_thumbnail_path);    $small_thumbnail = $small_thumbnail_path . $fileName1;        $medium_thumbnail_path = "uploads/large/";    createFolder($medium_thumbnail_path);    $medium_thumbnail = $medium_thumbnail_path . $fileName2;        $large_thumbnail_path = "uploads/large/";    createFolder($large_thumbnail_path);    $large_thumbnail = $large_thumbnail_path . $fileName3;        $thumb1 = createThumbnail($temp_path, $small_thumbnail,$fileType, 125, 125  );    $thumb2 = createThumbnail($temp_path, $medium_thumbnail, $fileType, 250, 250);    $thumb3 = createThumbnail($temp_path, $large_thumbnail,$fileType, 500, 500);                if($thumb1 && $thumb2 && $thumb3) {        $output['status']=TRUE;        $output['small']= $small_thumbnail;        $output['medium']= $medium_thumbnail;            $output['large']= $large_thumbnail;    }}echo json_encode($output);功能文件function createFolder($path){    if (!file_exists($path)) {        mkdir($path, 0755, TRUE);    }}

Answer 1

尝试这个缩略图函数，它获取源图像资源和缩略图大小，并返回缩略图的新图像资源。

function createThumbnail($src, int $width = 100, int $height = null) {

    // Ensure that src is a valid gd resource

    if (!(is_resource($src) && 'gd' === get_resource_type($src))) {

        throw new InvalidArgumentException(

            sprintf("Argument 1 of %s expected type resource(gd), %s supplied", __FUNCTION__, gettype($src))

        );

    }

    // Extract source image width, height and aspect ratio

    $source_width = imagesx($src);

    $source_height = imagesy($src);

    $ratio = $source_width / $source_height;

    // We know that width is always supplied, and that height can be null

    // We must solve height according to aspect ratio if null is supplied

    if (null === $height) {

        $height = round($width / $ratio);

    }

    // Create the thumbnail resampled resource

    $thumb = imagecreatetruecolor($width, $height);

    imagecopyresampled($thumb, $src, 0, 0, 0, 0, $width, $height, $source_width, $source_height);

    return $thumb;

}

鉴于上面的代码，您现在可以使用这样的函数

// Get uploaded file information as you have

// Create your source resource as you have

$source = imagecreatefromstring(file_get_contents($fn));

// Create thumbnails and save + destroy

$thumb = createThumbnail($source, 500);

imagejpeg($thumb, $thumb500TargetPath, 90);

imagedestroy($thumb);

$thumb = createThumbnail($source, 250);

imagejpeg($thumb, $thumb250TargetPath, 90);

imagedestroy($thumb);

$thumb = createThumbnail($source, 125);

imagejpeg($thumb, $thumb125TargetPath, 90);

imagedestroy($thumb);

// Don't forget to destroy the source resource

imagedestroy($source);