On 2/14/2025 6:05 PM, Pablo Rodriguez via ntg-context wrote:
On 2/14/25 17:13, Hans Hagen wrote:
On 2/14/2025 4:50 PM, Pablo Rodriguez via ntg-context wrote:
[…] The PDF key name is "Alt" […] Besides other questions related to the accessibility directive, it would be great to fix this issue.
As you tested viewers before, can you check which ones do something with Alt and/or ActualText at all?
Many thanks for your fast reply, Hans.
I attach the sample file (Alt value "this is a cow", ActualText value "hoh").
I don’t have access to a Windows computer now, so I cannot test Acrobat or Chrome/Edge now.
With "Alt", these viewers seem to find no "cow" (using the previous sample from Steffen): PDF.js, poppler (Evince/Okular), xpdf, mupdf-gl (and SumatraPDF).
With "ActualText", the compilant viewers are mupdf-gl (plus SumatraPDF), poppler (Evince/Okular), xpdf. PDF.js has only an open issue (https://github.com/mozilla/pdf.js/issues/12237).
So should one set both? Does it hurt? I suppose one is used for speach and another for copy-paste and that viewers mix and match what they like here. Could have the same values (when we set label) You can try to uncoment in lpdf-tag: -- Alt = alternate, -- Alt = pdfunicode(label ~= "" and label or "image"), irr we commented because some validator didn't like it but maybe we should not care about that too much. (Could also be under \enableexperiment control). Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------