Hello Gus,

The logs help, thanks.
The application crashes when the statistics are summarized, because there 
is not enough memory to store the mutual statistics for your 3582 images.

In short, the mutual statistics between couple of images (i,j) are stored 
in matrices of size NxN (N = 3582 images in your case).
Each matrix holds something useful (e.g. pixel count, pixel sum, ...) for 
each band.
In the end, all these matrices occupies a lot of memory! that's why the 
Mosaic application consumes so much RAM when you enable stats computations.

You have different ways for solving this problem (alternatively to run on a 
computer with more RAM!):
1. Give a try with a single thread. This will reduce the number of internal 
accumulators for statistics (matrices) because each thread has its own. To 
do that, set the ITK_GLOBAL_DEFAULT_NUMBER_OF_THREADS to 1 (type "export 
ITK_GLOBAL_DEFAULT_NUMBER_OF_THREADS=1" 
in terminal before running the command). But... this will last 4 times 
longer that your precedent try, something like 25 hours instead of 6 just 
for the stats computation. But you should save about 6Gb (approx for 3k 
images). However, let's hope that the later quadratic optimization step, 
which also requires to allocate space for matrix, will not fail.

[image: path4668-3.png]
2. Split your dataset in two (or more, if two isn't enough) the right way. 
You can  theoretically obtain the exact same result as if you process the 
whole dataset. For this, you need to split the dataset the right way to 
make the quadratic optimization equivalent. This can be done in finding a 
number of overlaping images that are connected only with one single image 
(i.e. this image would have 2 overlap with the adjacent images, and those 2 
adjacent images does not intersect). Then you process independently these 
two split independently (using the same harmo/comp options) and later you 
can process the mosicing of those two resulting mosaics (using the same 
harmo/options as you did for each one). The harmonization should be 
equivalent. See attached figure

Hope that helps !

Le samedi 29 septembre 2018 00:07:15 UTC+2, Gus a écrit :
>
> Ok. Here there are the logs and the output of gdalinfo on some random file 
> (all them were processed with gdal_translate).
> The harmonization pipeline failed. During statistics evaluation it showed 
> a progressively increasing memory footprint. I add a capture when it failed.
>
> [image: Screenshot at 2018-09-28 23-57-06.png]
> Thanks
>
>

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