file compression with cortex M4

Hi

I'm using a kinetis K64 cortex M4 with FreeRTOS and I need to compress files on a SD card. I have 100-150ko free Ram.

Do you know a library for this ? I found only solutions with 1Mo minimum RAM requirement.

It's csv files. I have a lot of time available to compress ; the cpu load is not a problem.

Decompression must be on pc.

thanks in advance