[bounty] Google+ (private ) communities: export screenscraper + importer

marketplace
43

I am pretty sure that I had rebased on master well before I ran that import. Reading the code, the bug is in embedded_image_html which doesn’t preserve aspect ratio:

    def embedded_image_html(upload)
      image_width = [upload.width, SiteSetting.max_image_width].compact.min
      image_height = [upload.height, SiteSetting.max_image_height].compact.min
      upload_name = upload.short_url || upload.url
      %Q~![#{upload.original_filename}|#{image_width}x#{image_height}](#{upload_name})~
    end

There’s not any multiplication or “square rootification” in there anywhere. About 20 years ago, my quick hack shell script to create indexes of images did this:

        eval $(identify -format 'OLDWIDTH=%w;OLDHEIGHT=%h' $file)
        NEWWIDTH=$(echo "sqrt(($AREA*$OLDWIDTH)/$OLDHEIGHT)" | bc)
        NEWHEIGHT=$(echo "sqrt(($AREA*$OLDHEIGHT)/$OLDWIDTH)" | bc)
        THIS_GEO="${NEWWIDTH}x${NEWHEIGHT}>"

That formula is a few millennia old, so I don’t claim any credit, and similar logic could keep aspect ratio while honoring the most restrictive constraint.

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