images api is suddenly corrupting output when source image is tiff (1bit 
group3).  Code that worked fine for over a year is suddenly and unexpectedly 
corrupting output images with no warning or error.  
This affects all images API functions in production.

This is a silent killer for our app as we receive fax data as tiff and convert 
to png before storage and other operations.  The system doesn't error, the 
output image is just suddenly corrupted.  I have posted a detailed entry on 
stack exchange with code examples:
http://stackoverflow.com/questions/16405881/google-appengine-images-api-suddenly-corrupting-images

I have also attached a sample project that shows the problem very clearly.

Please help!  Our production system is totally knocked offline because of this! 
:(

  * How can someone else reproduce the problem? 

Simply load a 2 channel 1 bit group3 compressed TIFF (a fax image) into the 
images service and convert it to a PNG.  The output will be corrupted.  I have 
created an example app to illustrate the problem:

Source image as TIFF: http://devtest-app1.appspot.com 
Convert PNG (corruption): http://devtest-app1.appspot.com?convert=1 
<http://devtest-app1.appspot.com/?convert=1> 

  * What is the expected output?  A NOT corrupted image, as it was for the past 
year.

  * What do you see instead?  A corrupted image.


I have filed a bug report:


https://code.google.com/p/googleappengine/issues/detail?id=9284


I have tried switching to PIL for the image conversion and PIL does not support 
group3 compressed TIFFs.  So that's a no-go.


Our app is using the latest version of AppEngine and runs with the python27 
runtime.


Please help!  We need a viable workaround, this is killing our production app.  
Google's service just started suddenly corrupting images without warning.  All 
our live data is corrupted now! We have had to turn off our production 
application until this can be resolved :(



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