On 2/14/25 19:18, Hans Hagen wrote:
On 2/14/2025 6:05 PM, Pablo Rodriguez via ntg-context wrote:
[…] 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?
Not for the same element, my fault.
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.
Alt is for speech and to replace non-textual elements. ActualText is intended only for textual elements (text itself or images that contain text).
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).
I will try to test this with the validators that come from the Arlington PDF model. BTW, ActualText doesn’t work in Edge (and I guess, Chrome [I don’t have access to a computer with it installed]). Many thanks for your help, Pablo