Should PNG Images be Interlaced if they're going to be used on the web?

[Blushock]

For PNG images, what if you are using them on the web, or if you have a slow internet connection? Should you use interlacing then? And what does it actually do? I think it loads a lower quality version of the image before replacing it with the proper one, but I'm not sure.

Original forum (now closed): 

 

[toe_head2001]

1 hour ago, Blushock said:

And what does it actually do?

 

Here's an article that explains:

https://arturth.com/what-is-png-interlaced/

[shadows]

Thank you for asking, Blushock. I also wanted to know.

 

What I get from the linked article is that interlacing makes the image load vaguely before filling in the details. A non-interlaced PNG will instead load from top to bottom. Usually, the image should not be interlaced (so keep the box in Paint.net unchecked).

 

Exceptions for when interlacing might be desired:

• When the viewers have a very slow internet connection.
• You'll be displaying many large images at once.
• (My interpretation as someone mindful of the harm flickering images can do to light sensitive people who are on slow internet connections:) There's a strong need to reduce flickering.

More experienced designers, is there anything else we should be aware of?

[kreemoweet]

Interlaced images are simply an annoyance, under any circumstances.

Don't do it.