Why are movies/video-clips counted with 本?


I just noticed in my Facebook uploads that for my videos, it says I have
`25本`. What's the reasoning behind using `〜本` to count videos or movie clips?
The only line of reasoning I can come up with would be thinking of the the
movies as as old reel of actual film

    ![enter image description here](https://i.stack.imgur.com/oRPXt.png)

Even though they are circular, they are more flat than long, so I would think
those would be counted as `〜枚` instead of `〜本`.

So what's the reasoning for using `〜本`?




A good resource for this type of question is
[『数え方の辞典』](http://www.amazon.co.jp/dp/4095052015/). It includes the following:

> 映画の作品数・上映数は「本」で数えます。細長い映画のフィルムが、巻かれた状態でひとつの作品として扱われることに由来します。

There is further information on various cases when it may be counted as 作, 作品,
巻き, 巻 (kan), 齣 (koma), カット, シーン, 場面 etc. For more details, I recommend
consulting this at a library or getting your own copy.




A good resource for this type of question is
[『数え方の辞典』](http://www.amazon.co.jp/dp/4095052015/). It includes the following:

> 映画の作品数・上映数は「本」で数えます。細長い映画のフィルムが、巻かれた状態でひとつの作品として扱われることに由来します。

There is further information on various cases when it may be counted as 作, 作品,
巻き, 巻 (kan), 齣 (koma), カット, シーン, 場面 etc. For more details, I recommend
consulting this at a library or getting your own copy.

