alto2hocr: Hyphenation sign is not handled correctly

[zuphilip]

Example (the dash is actually normally an em dash):

   ...
   <String WC="0.6233333349" CONTENT="con" HEIGHT="26" WIDTH="79" VPOS="132" HPOS="596" SUBS_TYPE="HypPart1" SUBS_CONTENT="conservation"/>
   <HYP CONTENT="­-­"/>
</TextLine>
<TextLine HEIGHT="43" WIDTH="679" VPOS="175" HPOS="12">
   <String WC="0.7411110997" CONTENT="servation" HEIGHT="43" WIDTH="194" VPOS="175" HPOS="12" SUBS_TYPE="HypPart2" SUBS_CONTENT="conservation"/>
   ...

will be transformed into

   ...
   <span class="ocrx_word" id="word_d1e73" title="bbox 596 132 675 158">con</span>
</span>
<span class="ocr_line" id="line_d1e76" title="bbox 12 175 691 218">
   <span class="ocrx_word" id="word_d1e77" title="bbox 12 175 206 218">servation</span>
   ...

and the dash is missing. For correct presentation (and error computation) it should be part of the first word here. Can this been easily done with the XSLT approach here?

[stweil]

Obviously ALTO uses a <HYP> tag which is currently not handled by the transformation. I did not find a similar tag in the hOCR specification.

http://digi.bib.uni-mannheim.de/~stweil/ocr-praxis/Testseiten/hocr/417576986_0012.hocr is the result of an extended style sheet where I used a quick hack to produce something useful.

[zuphilip]

Hm.. I see an extra node in your result which results in another space. Our goal is to receive

<span class="ocrx_word" id="word_d1e73" title="bbox 596 132 675 158">con-</span>

I think we can try to replace these lines with something like

 <xsl:template match="String">
    <span class="ocrx_word" id="{mf:getId(@ID,'word',.)}" title="{mf:getBox(@HEIGHT,@WIDTH,@VPOS,@HPOS)}">
        <xsl:value-of select="@CONTENT"/>
        <xsl:value-of select="preceding-sibling::HYP/@CONTENT"/>
     </span>
  </xsl:template>

But this is untested...

[zuphilip]

Ping @kba . Here are two examples of ALTO files with hyphenations (just search for HYP node):

• official example from the ALTO community: http://chroniclingamerica.loc.gov/lccn/sn86069133/1910-10-31/ed-1/seq-1/ocr.xml
• one of our examples: http://digi.bib.uni-mannheim.de/fileadmin/digi/417576986/alto/417576986_0078.xml

It looks that CONTENT is empty in our HYP tags, i.e. we may have to do something like an conditional statement.

[kba]

Here's a small change to the alto2hocr.xsl script that should accomplish this: https://github.com/kba/hOCR-to-ALTO/commit/f447acea8cc90f8085e031d058626968475f4a0a

[filak]

This https://github.com/kba/hOCR-to-ALTO/commit/f447acea8cc90f8085e031d058626968475f4a0a has been merged - so this issue might be closed...

[zuphilip]

I wasn't sure anymore if this was already included. Thank you for the confirmation @filak !