PNG files pixilated transparency : problem: the transparency on my PNG files was pixilated and not smooth. However the edges were smooth in Firefox and Google chrome. The problem only seems to be happening with one image in particular. This means that it is likely a problem with the way I exported the photo. Let’s try to export the photo again with different settings.
using fireworks export using a PNG 32 setting with the matte set to transparent.
More details here: http://kb.adobe.com/selfservice/viewContent.do?externalId=tn_14647
Result: decent file size, true alpha transparency, no pixelated edges in older versions of Internet Explorer or any other browser (using the PNG alpha transparency in Internet Explorer hacks: http://www.dailybits.com/png-alpha-transparency-in-internet-explorer/ )
Article notes and keywords:
This problem is definitely related… when I edited the PNG files in fireworks and just save them as opposed to exporting them with transparency the files were much smaller however they appear jagged.
Paper top.PNG file
original: 14.5 kB
exported: 5 kB
saved: 60 kB
Try tweaking your export settings
verified that a PNG save out of fireworks produces a high file size and high quality transparency compatible image for Internet Explorer.
I also confirmed that after uploading the PNG file that I was unable to get the PNG file out of Internet Explorer cache. Google chrome did not have a problem refreshing to see the new PNG image.
Second try: fiddle with the PNG export settings
PNG eight adaptive, 64 colors, no transparency: 71 kB
PNG eight adaptive, eight colors, no transparency, 65 kB
PNG eight, Web adaptive, eight colors, no transparency, rebuilt color table, 66 kB
PNG eight, adaptive, 32 colors, no transparency, exported, broken transparency, 3 kB
fifth try: PNG eight, adaptive, 256 colors, Alpha transparency, red background, five k bytes pixelated edges.
====================Alpha image loader PNG files stuck in browser cache ====================
Another problem I’m having is the PNG files that I am uploading to not seem to be displaying in the browser. They seem to be showing the old image and not the new image. So the server-side image does not appear to be updating. Is it stuck in some kind of browser cache ?