当在来自不同应用程序的 URL 上调用 reverse() 时，你应该使用它的命名空间"版本，就像这样:

When calling reverse() on an URL that comes from a different application, you should use its "namespaced" version, like so:

{% url 'app_name:app_url' %}

在您的具体情况下，这转化为:

In your specific case, that translates to:

{% url 'picture:upload_image' %}