I've run into a problem with images I'm converting from another source. The most accurate intermediate format seamed to be .png, however; I've run into a repeated problem with some images display. On certain images, some of the text rendered has been misscaled and is inconsistant with the surrounding image. The text is correctly located on the displayed image. At first, I thought this was a problem with the software generating the .png file from its source. These are ChemDraw format images and are being converted by ChemDraw. In further looking at the intermediate, I find I can correctly view the .png file with other windows utilities without the font scale problem. These utilities Paint and Windows Photo Gallery also have no problem scaling the image. I have also attempted enabling .svg image format hoping it would be a convenient intermediate, but; the added work to support browsers without native .svg gave me pause.
Can anyone familiar with the .png scaling process comment on why (only certain) text in .png files does not scale properly? I'm using MediaWiki 1.15.1. Thanks for any help.