Typically when I see this, it is an issue of font availability. Often a file created on one system, such as Windows or Mac in the case of Excel, use fonts that are not installed by default on the system reading and rendering the file (often Linux based servers). Usually missing fonts are handled in a "best effort" manner looking for a similar font in terms of serif/sans-serif, etc. These substitute fonts may not have as many characters defined as the original, which can lead to generic "missing glyph" symbols like the "?" you see in the output.
The solution depends on the system, and is outside the scope or control of POI. You can load fonts at the OS level, and additionally at the Java level, if you can package them in your code. Be careful of licensing, however, as many fonts are only legally installable with the proper license, such as many fonts distributed with MS Office. They are available for purchase from Microsoft or one of their partners somewhere, I've seen it before. Google is your friend for that task. You can also experiment with open-source fonts on your own and install them, looking for one that supports the characters you need with metrics close enough to the original for your purposes. On Wed, May 17, 2017 at 10:54 AM mrjack88 <oscar.cabr...@vcl.desoft.cu> wrote: > Hi there again. > Thanks for answering my question. Here i have a new one. I have a pptx file > with some japanese text inside, when i got the rendered images from pptx > file there are some lines that gets displayed ok, but there are some lines > displayed as squares with "?" character inside. I think that if there is an > encoding problem, then all lines would show up as squares; do you have a > comment on this. if you need the problematic file to test it, how can i > send > it to you? > Cheers > Oscar > > > > -- > View this message in context: > http://apache-poi.1045710.n5.nabble.com/xlsf-slides-wont-show-charts-or-shapes-on-png-export-tp5727430p5727572.html > Sent from the POI - User mailing list archive at Nabble.com. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: user-unsubscr...@poi.apache.org > For additional commands, e-mail: user-h...@poi.apache.org > >
