[Plugin] Access-Aide - help improve epub accessibility

[KevinH]

Please run that jpeg through a verifier. Segments and markers are normal parts of the jpeg spec so something is wrong.

[KevinH]

I will update the version in the first post but this error is not the same as what was fixed in 0.9.5 to make 0.9.6.

I think that jpeg is corrupted. Either way I will need to prevent the error. I will look into this tonight when I get back home.

[DiapDealer]

Originally Posted by KevinH

I will update the version in the first post but this error is not the same as what was fixed in 0.9.5 to make 0.9.6.

No need. I was mistaken. It says 0.9.5 is the latest version at the beginning of the first post. But 0.9.6 is indeed attached to the post.

[KevinH]

It is a bug in my code due to whitespace being missing.
That if marker test should be indented to be underneath the if that defines it.

That needs to be fixed with a new 0.9.7 release hopefully tonight.

The bug is only triggered when no APP1 section is present.

[KevinH]

The hopefully last fix for that whitespace bug is now in version 0.9.7 which was just posted (see the first post in this thread or my gihub site).

[oston]

Many thanks, Kevin.

Ran the 0.97 plugin on the epub that generated the earlier error. This time no error messages were generated.

I was puzzled by the fact that no alt-text entries were added even though the jpg files had alt-text in their metadata. But then I discovered something that I had not noticed before. The files in Images in the Sigil Book Explorer were png files, not jpg files. The jpg files with the metadata had been converted to png files during the export from InDesign and all the metadata was stripped in the process.

When I re-exported using the Existing Image for Graphic Object. everything worked as expected with the plugin.

Many thanks for this Kevin. I think I will now change my workflow to save the alt-text in the Image metadata and remember to use the Existing Image during the export from InDesign.

[KevinH]

Glad to hear it.

FWIW, xmp metadata can be used (stored and retrieved) in PNG files as well as JPEG, TIFF and WebP images. Access-Aide should now be able to extract it from any of those formats if it exists.

So InDesign isn't bothering to copy the metadata over to the PNG format at all when it converts the JPEGS to PNG.

Sad they strip it out. Probably to save space.

[oston]

Yes, one of the images in another test epub was a png file with alt-text in its metadata.

[noteon]

My world went dark with despair when I saw that AccessAide won't work on books with javascript/media. Any chance this will change? And if not, do you know anything better than pasting alt text into code manually?

[KevinH]

As clearly stated in the first post of this thread, Access Aide entire purpose is to make sure an epub meets the criteria for:

schema:accessMode: textual
schema:accessMode: visual
schema:accessModeSufficient: textual
schema:accessibilityFeature: structuralNavigation
schema:accessibilitySummary: This publication conforms to WCAG 2.0 AA.
schema:accessibilityHazard: none

It can NOT make this claim reliably for anything that includes media or javascript ( ie. movies, animations, or audio) as Access-Aide has no ability to see or hear if the media contains hazards such as quickly flashing images or loud noises that could induce seizures or other create potential accessibility or health hazards.

http://kb.daisy.org/publishing/docs/...ityHazard.html

That is why I limit its use to standard fiction epubs. There are human based ACE accessibility certification boards that can and will certify that an epub with those features do not present any hazards.

You can always run Access-Aide on early versions of the epub before adding in media and javascripts for animations to help fill in alt descriptions, update descriptions and semantic tags, but ... once media are added, you really should use a true certification service to make sure that there are no visual or audio hazards unless you are an expert in exactly which video or audio elements might present as hazards. I am not. Someone would have to hear and see every movie frame and audio, and watch any javascript created animation or movements.

Access-Aide itself, can not and will not make the claim there are no accessibility hazards, as it can not verify that.

If you want, I can create a version of Access-Aide that does NOT include the certification metadata. Then you can of course run it on anything, but you must then take the risks associated with whatever certification *you* decide to apply.

[noteon]

Totally understood. I'm just used to using it for alt text insertion in reflowables, and bumped into this issue on interactive fixed-layout epubs.

Unfortunately, I can't run any plugin before adding media and javascript, since that all happens in InDesign before exporting the epub.

I would certainly not turn down a version without certification metadata, if you thought it was worth your time. Or even a version that does nothing but add alt text.

Thank you!

[KevinH]

I will create a variation of the Access-Aide plugin code "plugin.py" that does not stop when it sees media or javascript but will no longer add the metadata certifications.

You can then use that "plugin.py" to replace the one in Access Aide to create your own plugin variant.

[KevinH]

Attached is a replacement_plugin_py.zip

Download and unzip it to create a file called "plugin.py"

Then go to your Sigil Preferences Folder, into the plugins folder and then into the Access-Aide folder. Copy in this new plugin.py to replace its namesake inside the Access-Aide folder.

Completely exit out of Sigil. Then fire up Sigil.

Your Access-Aide plugin will now have been modified to not abort if mathml, javascripts or multi-media are used in the epub. But at the same time it will no longer update the opf metadata to add any accessibility metadata.

It is a very easy set of delete changes from the original plugin.py code so unless I over deleted something this should work.

Please give that a try and let me know if you run into any difficulties.

KevinH

[noteon]

Wow, thank you! I'll start using it on a job I have in this week.

[KevinH]

FWIW, I am thinking of making the addition of the accessibility schema metadata contingent on no mathml, no javascript, no multi-media instead of aborting if they are detected in a future release of Access-Aide as that sounds like a good compromise.

That way one plugin works in both cases.