[NTG-context] Re: Alternate text for images?

15 Apr 2025

      On 4/15/25 19:10, Hans Hagen wrote:
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On 4/15/2025 5:24 PM, Pablo Rodriguez via ntg-context wrote:
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[...]
All I know is that it has to be fixed in lpdf-tag.lmt, but I don’t know
how to fix it.
you can move the Alt and test
local d = pdfdictionary {
             Type = pdf_mcr,
             Pg   = pageref,
             MCID = last,
         }
         parent.dict.Alt  = pdfunicode(label ~= "" and label or "image")
Many thanks for your reply, Hans.

This fixes the issue.
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It is the same for alternative texts in formulas for PDF/UA-1.
you can play with
-- Alt        = alternate,
                 NS         = namespace,
                 ActualText = actualtext or nil,
Alt        = actualtext or nil,
                 NS         = namespace,
              -- ActualText = actualtext or nil,
and such to see if your viewer does soemthing useful
I get an /Alt key automatically generated by ConTeXt, but I get:

  18 0 obj
  <<
    /K [ 19 0 R ]
    /P 15 0 R
    /Pg 1 0 R
    /S /formula
...
...
endobj
19 0 obj
  <<
    /K [ 23 0 R ]
    /P 18 0 R
    /Pg 1 0 R
    /S /formulacontent
...
...
endob
23 0 obj
  <<
    /AF 22 0 R
    /Alt 
    /ID (math-0001)
    /K [ 2 ]
    /P 19 0 R
    /Pg 1 0 R
    /S /math
...
...
endobj
/Alt is in object 23 and it needs to be in object 18 (which is tagged as
/Formula), how do I get that?

Many thanks for your help,

Pablo