No Data management study

Actual NoData management in OTB isn't satisfying for users. Behavior to handle NoData can differ depending of applications.

• List actual NoData issues, what are the different problems
• List the most common OTB application and what are the expected NoData managing behavior ?
• Group the behaviors, can we make common code about it ?

Definition of Done

• A list of existing issues related to NoData problems
• A list of OTB application where it is relevant to manage NoData automatically
• Another one where NoData management can not be guessed (thus led to user)
• A list of NoData management behaviors
• A list of tests to write to check these behaviors.

Existing issues

• #1798 no data in BandMath
• #2398 no data in SARCalibration
• #1849 no data in otbcli_DimensionalityReduction
• #2406 information in metadata appearing twice
• #2366 SuperImpose takes no data in its computation
• #2341 Doc unclear about nodata in extended file names, also GDAL raise a warning (to check on recent OTB version)