问题
I'm using Laravel with this package https://github.com/mewebstudio/captcha and for some reason It's not displaying the images. I checked if GD library is installed and enabled and it is. I've also tried this one https://github.com/igoshev/laravel-captcha and same thing happens. I cannot see image on the page and when I inspect the page I can see the URL to the image, but when I click it it's just black.
来源：https://stackoverflow.com/questions/47232432/php-captcha-not-working