Pycuampcor V2

[rtburns-jpl]

Merging upstream changes from Lijun for PyCuAmpcor, and changes from @vbrancat to fix the runconfigs and parsers to support his newly-added parameters

See corresponding PR in isce2 (isce-framework/isce2#922):

PyCuAmpcor Version 2 introduces a new workflow inspired by GrIMP/SpeckleSource, in addition to the original ROIPAC/ampcor workflow. Below is an overview of the new workflow and additional improvements:

Key Features of the New GrIMP/SpeckleSource Workflow:

* Starts with an anti-aliasing oversampled secondary chip over the entire search range.

* Adds extra margins to facilitate correlation surface extraction.

* Offers optional double-precision computations (also extended to the ROIPAC/ampcor workflow for consistency).

The GrIMP/SpeckleSource workflow may be slower than ROIPAC/ampcor due to increased computational demands. However, it may improve accuracy in scenarios with low signal-to-noise ratio (SNR). More details on the workflows and how to choose can be found at contrib/PyCuAmpcor/README.md.

Other Improvements

* Introduced an option to fix the starting pixel location, which is ideal for comparing results from different window sizes.

* Added an example script for plotting the offset field, making it easier for users to visualize results.

* Included correlation peak values in the output, alongside SNR and covariance, providing additional accuracy measures.

* Resolved a memory deallocation issue that occurred when the run procedure was called repeatedly within a single script.

[hfattahi]

Thanks @rtburns-jpl . Would you please add the description from the parent PR in isce2 as well as all the changes that @vbrancat contributed.
Also would you or @vbrancat document some of the tests done for this PR.

[hfattahi]

@lijun99 you may want to take a look at this PR.

[lijun99]

Thanks @rtburns-jpl ! There is one more bug fix, fix the distance in variance estimate in one-pass workflow. Also, to make it easier for inclusions in both isce2 and isce3, I plan to move future developments of pycuampcor to the independent repo cuAmpcor. Please decide whether you prefer to copy the code over to isce, or use submodule like this.

[lijun99]

Also, there are more spelling errors, which are corrected in this commit.

[rtburns-jpl]

Thanks! Yeah, I agree consuming pycuampcor from a separate repo would make updating it much easier. I'd also like to contribute my CPU-only translation of pycuampcor to your repo, if you're interested.

[lijun99]

Sounds great, @rtburns-jpl ! I just sent a collaborator request for cuAmpcor. Maybe we should use a new name like ampcor, under isce-framework or earthdef (Mark's group).

[vbrancat]

LGTM

[hfattahi]

@lijun99 After our upcoming delivery we should discuss the modular approach where PyCuAmpcor will be an external module. That will definitely be a preferred approach over long run.

[hfattahi]

Thanks @lijun99 @rtburns-jpl and @vbrancat for this extensive PR, testing and verification. Took a long way to get it here. Based on the test results from @vbrancat LGTM.

[hfattahi]

@rtburns-jpl Let's NOT merge this PR for now as the MCR is not approved.
@vbrancat let's please have an independent PR for increasing the memory buffer to allows large parameters for very fast ice.