将高图画布保存为服务器上的png图像

Question

我只是想知道是否有人能够将高清图的画布图像保存到他们的服务器上。 我可以很好地在画布上渲染高光图，但是当我将它保存到服务器时，图像本身是空白的，但文件大小为6kb。 出于测试目的，我只是在画布图像的dataURL中进行硬编码，但仍然无法显示图像（我只是排除了这样一个事实：我的情况并非如此转移生成图像时正确的数据）。 我也试过采用云的常规dataURL，图像看起来很好。

$img = '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';

 $data = base64_decode($img);
        $file = 'download/image3.png';
        $success = file_put_contents($file, $data);
        print $success ? $file : 'Unable to save the file.';

任何人都知道可能出错了什么？我需要将这些图像保存为服务器上的图像，因为我需要在之后以pdf格式显示它们，但似乎无法找到另一种解决方案。我也使用代码点火器。