I've been working at audio area for more than 10 years. This project is quite easy to me. I'm just new to this website and I'm trying to build my reputation from this project :-). At present, I'm working in an US audio related company.
I'll use the library from ffmpeg to demux and decode the audio from m2ts file. The decoded audio might be multiple channels. I may need to downmix them to mono channel. I can also give dB value for each channel based on your request. Maybe you'll have other similar requests, e.g. display loudness, etc. I can always meet your request!
Cheers,
Richard