How to reduce the size of matter.ota firmware? Are there any compression method?

[Llama12580]

Building project with configure file `prj_release.conf` can reduce size of matter.ota, but I still think it is large. 

I want to reduce the size of matter.ota file, are there any compression method for nordic, like "lzma" compression for silabs EFR32?

[AHaug]

Hi,

Could you expand upon your motivation for compressing?

The reason for why I'm asking is if you're struggling with having enough room on the secondary application slot on the nRF where you store your update image, then compressing it will not solve this issue.

If you need this because you want to compress the update firmware before transport, then send it, and decompress it on the nRF side then this should be possible with proprietary solutions, but we don't have anything out of the box solution for this.

Kind regards,
Andreas

[Llama12580]

Hi,

Because I want to make it possiable for my custom board of nrf52840 which only has 1MB flash to upgrade by matter ota, is it possiable?

[AHaug]

Hi,

Unfortunately you will need more than 1MB to support dual bank DFU for a Matter application, so an external flash is required for current SoCs that support Matter. See https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/protocols/matter/getting_started/hw_requirements.html#external-flash for more info + the Matter specification which states that DFU is mandatory for a Matter application.

But for general Matter footprint optimization you can have a look at https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/protocols/matter/getting_started/memory_optimization.html

Let me know if this answers your question

Kind regards,
Andreas