podi_imcombine Module

This module contains all functionality for combining a number of input frames into one output frame by performing a user-sdefined function on the range of input values of each pixel.

To improve performance, the actual image-combination step is executed in parallel, split by line. Furthermore, each extension is computed in a new process, enabling better memory management by the operating system. This enables memory-limited operation with very little memory loss/leakage between extensions.

Example:

For unbinned pODI (13 OTAs) frames, memory demand is roughly 1 GB + 65MB x numer of frames. Assuming 6 GB of available memory, this would practically (avoiding memory swapping) to 75 input frames.

Standalone option:

Combine a set of input images and write output to disk

podi_imcombine.py (-op=xxx) output.fits file1.fits file2.fits ...

podi_imcombine.imcombine(input_filelist, outputfile, operation, return_hdu=False)

podi_imcombine.imcombine_data(datas, operation='nanmean')

podi_imcombine.imcombine_sharedmem_data(shmem_buffer, operation, sizes)

podi_imcombine.imcombine_subprocess(extension, filelist, shape, operation, queue, verbose)

podi_imcombine.parallel_compute(queue, shmem_buffer, shmem_results, size_x, size_y, len_filelist, operation)