如何在 PHP laravel 中将图像的透明背景转换为白色

有多种方法可以做到这一点，一种方法是使用php gd library

在您的情况下，它的工作原理如下:

public function updatePdoImage($request, $id)
{
    if (!$request->file('profile_image')) {
        return;
    }

    $request->validate([
        'profile_image' => 'required|image|mimes:jpeg,png,jpg,gif|max:2048'
    ]);

    $file = $request->file('profile_image');

    $image_properties = $this->uploadImage($file, 'uploads/');

    $data = [
        'file_name' => $image_properties[0],
        'file_dir' => $image_properties[1],
        'file_type' => $image_properties[2],
        'file_size' => $image_properties[3]
    ];

    $pdo = $this->show($id);

    // Open the image using GD
    $image = imagecreatefrompng($data['file_dir']);

    // Get the dimensions of the image
    $width = imagesx($image);
    $height = imagesy($image);

    // Create a new white background image
    $newImage = imagecreatetruecolor($width, $height);
    $white = imagecolorallocate($newImage, 255, 255, 255);
    imagefill($newImage, 0, 0, $white);

    // Copy the original image onto the white background
    imagecopy($newImage, $image, 0, 0, 0, 0, $width, $height);

    // Save the modified image
    imagepng($newImage, $data['file_dir']);

    // Convert the modified image to Base64
    $base64Image = base64_encode(file_get_contents($data['file_dir']));

    $data['grant_proposal_logo'] = $base64Image;

    // saving data in DB
    $this->savingUploadImage($pdo, $data);

    // Free up memory
    imagedestroy($image);
    imagedestroy($newImage);
}