It seems you're looking for the file for MX Player with the identifier v149.0 for ARMv8 NEON architecture (common on 64-bit Android devices).
Ensure the ZIP file is in your main "Download" folder and hasn't been unzipped. MX Player needs to read the zipped package. mx player custom codec 149 0 armv8 neon
If it says "S/W" (Software), the codec is not working. Go back and ensure you used the ARMv8 NEON 1.49.0 version. custom codec It seems you're looking for the
When looking for a codec, the filename usually looks like a string of technical jargon. Here is what v1.49.0 ARMV8 NEON actually means: v1.49.0 (The Version) If it says "S/W" (Software), the codec is not working
This article explains everything you need to know about the for ARMv8 NEON devices, including why you need it and how to set it up.