At what situations should I leave out 话 in "~的话"

Question

In the following sentence:

国籍的图片是来自于EmojiOne数据集，有兴趣的可以去看看了解一下。题目有奥运会奖牌，本次用国旗与国家联系起来。

This sentence seems to use "~的话，..." phrase, but omit the 话. (Let me know if I'm wrong but I proceed with the assumption that it is correct).

However, on these types of sentences I'm struggling to decide when to leave it in or out. How can I use them apart correctly? Is there any clue?

The above sentence should be fine if I rewrite it as following:

国籍的图片是来自于EmojiOne数据集，你有兴趣的话就可以去看看了解一下。题目有奥运会奖牌，本次用国旗与国家联系起来。

Or is it OK to always use the brief form as far as the meaning is clear enough in the context? I learned here that it is usually considered better to make the sentence simpler in Chinese, as far as it is clear...

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NOTE

One of the answer here writes the following but my question is about 话, not 的话 (I agree without 的话 it sounds an incomplete sentence). Also my question doesn't necessarily indicate 如果 or 要是.

Without 的话, it sounds quite abrupt, although it does work if you leave it out, in most cases.

Answer 1

This sentence seems to use "~的话，..." phrase, but omit the 话. (Let me know if I'm wrong but I proceed with the assumption that it is correct).

I think it omits 人 here; i.e. 有兴趣的 refers to 有兴趣的人 (people who are interested in). Using 人 makes the sentence more formal and polite, without it makes the sentence simpler and the meaning is still clear enough.

BTW ~的 is a common structure used instead of the referred people or things.

〈代〉 pron. 附着在词或短语之后,构成“的”字结构,代替所指的人或物。如:卖菜的;吃的

Answer 2

“有兴趣的” 代表 “有兴趣的人”。但是在这段话中，即使说“有兴趣的话”也说得通，但这里并不是这个意思。 Need to understand “……的话” means if...，比如：如果你能听懂的话，就很好- if this case, then what.. 如果……的话 is the structure