Hmm, interesting.
I’ve just created a test file with alt text on and object, and exported to IDML. I then opened up the IDML (which is just a zipped archive of XML files), to look through with a text editor.
The alt text IS in fact in the IDML file, under Spreads.
In my very simple sample it was in a file called Spread_uc3.xml, and in a section of XML like this:
<ObjectExportOption AltTextSourceType=”SourceCustom” ActualTextSourceType=”SourceXMLStructure” CustomAltText=”Alt text added in the dialog” CustomActualText=”$ID/” ApplyTagType=”TagFromStructure” CustomImageConversion=”false” ImageConversionType=”JPEG” CustomImageSizeOption=”SizeRelativeToPageWidth” ImageExportResolution=”Ppi300″ GIFOptionsPalette=”AdaptivePalette” GIFOptionsInterlaced=”true” JPEGOptionsQuality=”High” JPEGOptionsFormat=”BaselineEncoding” ImageAlignment=”AlignLeft” ImageSpaceBefore=”0″ ImageSpaceAfter=”0″ UseImagePageBreak=”false” ImagePageBreak=”PageBreakBefore” CustomImageAlignment=”false” SpaceUnit=”CssPixel” CustomLayout=”false” CustomLayoutType=”AlignmentAndSpacing”>
The alt text that I added is “Alt text added in the dialog” which appears under CustomAltText=”Alt text added in the dialog”
So it would appear that the filters used by our CAT tools aren’t picking this up as potentially-translatable text.
I wonder if the open source OmegaT with those Okapi filters would be configurable to do this? Sorry, but I don’t have the time or tech knowledge to test this.
Good luck,
Chris