Situation

Our product has a messenger where you can upload images. We want our product to be accessible. However, user uploaded photos may not necessarily have alt= tags in them.

What do we do?

Comparisons

Facebook Messenger, Intercom Chat and Freshdesk Chat don't have alt tags on their user uploaded images. Front App chat has an alt tag, which is simply "attachment".

Options

1) Generic alt tag: alt="The image you uploaded"

2) Blank alt tag: alt="". The screenreader will skip over the image entirely.

3) No alt tag at all. The screenreader will read the file name.

Reason for Option 3

Organization is critical to the lifestyles of the visually impaired individuals (references and forum example). I'm assuming the same care goes towards naming digital files. In particular, graphical files (e.g. jpg, png). Meaning they would name their images in such a way that accommodates finding it among other images.

Having the screenreader read out this image title (if no alt="" tag is present` vs. "your attachment" or skipping entirely is much more helpful in identifying which image or file is in the chat timeline.

I'm making this assumption knowing that deeply ingrained habits carry over to many aspects of life. And unfortunately I can't find anything specific about naming file conventions or folder structures on computers/devices for visually impaired users.

Small caveat: For obscure file names (like iPhone's IMG_123514), these will still be interpreted by the user as images from their prior experience with screenreaders dealing with images across the web and on their own devices.

Anyone have any thoughts here, and/or references to look up?

Thank you very much! :)