Hi,
I am a practitioner in film industry, and I have found that there are slight differences in the packaging methods used for ARRIRAW files on different camera models. For example, usually the packaging method corresponding to Alexa LF is ARRIRAW 12-bit packed, while AELXA mini LF corresponds to ARRIRAW 12-bit reverse packed.
I have consulted a lot of information on what the reverse here actually means, and I have obtained an explanation in SMPTE RDD 54:2022 Material Exchange Format - Mapping ARRIRAW Bitstreams into the MXF Generic Container.
In this file, it is written that the difference between ARRIRAW files that do not use reverse packed and ARRIRAW files that use reverse packed is that there is an additional step of 'Starting with the first 16 bit word, the two values in each successful pair of words should be swapped.'
Based on my understanding, I believe that these two packaging methods may differ in the order and manner in which RGB values are stored. But I am not sure about the differences in the use of these two methods, and I have not found any relevant information. Especially, why does Alexa mini LF use reverse packed, which is different from Alexa LF and Alexa 35.
Ryan