Unsupported compression: AEC/SZIP


In one of my tests I make use of AEC/SZIP compression. From the forum discussion ZFP compression supported? - HSDS - HDF Forum (hdfgroup.org) I understand that this compression type is not supported. That is fine. However, when I try to use it, I would expect to get an error saying it is not supported but instead I get no error at all and the data are stored without compression. My question is this done on purpose or would it be better to report an error?

Best regards,

This is likely due to the REST VOL not preserving the optional/mandatory flag for each filter upon re-opening a dataset - see this github issue for details.

Thanks for creating an issue about it.

While reading the issue, it became clear to me that the observed behavior is intended. Since I made use of H5Pset_szip() the filter is optional. I did not know this and as far I can tell it is not mentioned in the SZIP documentation. However, it is implicit mentioned in the documentation of the function H5Pset_filter(). Maybe an idea to improve H5Pset_szip() documentation by mentioning it is optional filter and point to the H5Pset_filter() documentation what this actually means.