How to prevent the Android Market from JPEG-compressing the Promotional Graphic PNG?

I recently uploaded a new application to the Android Market (this application). I also uploaded a hi-res application icon, a feature graphic and a promotional graphic.

However, the promotional graphic gets a really ugly JPEG compression. This is the image I uploaded:

This is what the Android Market makes out of it:

Interestingly, the Android Market seems to convert it to a JPEG image, but preserves the .png file extension. Is this a bug?

Here is what I tried to solve the problem:

1. Checked that the image has no alpha transparency, is 24bit and has the right resolution (as described here).
2. Created a PNG with optimized palette of 256 colors and uploaded it. It still gets converted to JPEG, alth开发者_JAVA技巧ough the original PNG file is smaller than the resulting JPEG file.
3. Created a JPEG with low compression and uploaded it - but the problem is the same.

Is anybody having the same problem? What did you do to fix it?

Thanks a lot for helping!

Use small images in kilobytes e.g. <5KB will do the job.

Uploaded promo image has to be quite small or Market will "process" it automatically (reduce its size). I had the same problem with >8KB images and at the end all went right with 3KB PNG/5KB JPEG files. Try using less colors, less effects, reduce quality, try with dithering also. At the end you will always make better quality image than Market will after processing (size reducing).

You can test/check this by yourself: - login to Android Market - upload promo image for your APK - open uploaded image in new window/tab and save it locally to your harddisk - check image size! it is a lot smaller than original ~15KB. Mine was ~3KB and original was ~17KB

Try these ones I made in photoshop. They're not perfect, but the size is much smaller so it may get a better treatment in the market:

• saved for web, 100%, ICC profile, 0.2 blur:

  

• saved for web, 100%, ICC profile, no blur:

  

Try these, I've made them in Adobe Fireworks, used simple Save As, with 2 different JPEG compression options (80% and 90%). Let us know, I would like to know the answer myself ;-)

JPEG 80% http://cl.ly/0m2c412p212n1r1w101u
JPEG 90% http://cl.ly/0627030I1U0P1R173W33

Sorry I can't insert pics yet as new user.

This is just a thought, but have you tried contacting someone at the Android Marketplace about it?

Down at the bottom of this page, they have links to contact them directly:

https://market.android.com/support/bin/answer.py?answer=136601&hl=en

Converting the PNG file to a JPEG yourself and uploading the JPEG should have helped, especially if you applied dithering in the solid color areas. You may have to give it a little while for the upload to actually take effect and for the new version to appear on the Market's servers.