How to save audio from MKV clip to MP3?

Hi folks, Sorry if this belongs in one of the subforums... wasn't sure which to use since this touches several areas. I have an MKV video clip, that I'd like to extract the DTS or AC3 audio from, and save as an MP3 for eventual use as a phone ringtone. I don't seem to have the right utility to do the job, but figure it's a basic task lots of others here have done. Can you please recommend which tool to use? I started with a TV episode (45 minutes in MKV format) and used MKVMerge to split out the 25 seconds or so I wanted. So, the result is a 25 second MKV file, with the audio track, and either with or without the video track depending on what I select to keep in MKVmerge. But, I have not found a utility that will import the MKV (audio or audio/video) and export an MP3. Tried Handbrake, Vidcoder, Videopad. All of them are designed to work with video, and barf if I want to work with just audio. I'd appreciate any help. Thanks! Marc

It was ripped from a Bluray that I own by MakeMKV. It's got H264 video and in this case DTS audio. However, sometimes I might be interested in doing the same thing with AC3 (DD) audio or on MKVs from DVD that are Mpeg2 video. I'm sure there's a simple utility that will take a plain audio track and save as MP3, I just haven't yet found it! :o

Demux the audio ES from the MKV (e.g., with DGDecNV) and then transcode as needed (e.g., with BeSweet).

OK, thanks for the help. I'll investigate the process you posted and report back, hopefully with success, so others with the same issue can easily find the answer. I appreciate your help! Marc

You can also demux the ES with mkvextract as well.

STill working on it. I've got the demuxed audio, but since it's .DTS, BeSweet won't work on it. I'll poke around for a more up to date transcoder.

One option for you: eac3to foo.dts foo.ac3

Thanks neuron2! I greatly appreciate your continued help. Turns out the easy way to do it once I had the .dts demuxed stream was to use Wavepad's free trial. I was able to input the .dts file and save as an .mp3 with no problems. I did poke around a bit with besweet but found the format of the inputs and switches and stuff more trouble than I wanted to spend too much time on. I've now got my .mp3 ready for transfer to my phone. For anyone that later reads this, here's the final process I used: 1. Starting with an MKV, I extracted just the segment I wanted using MakeMKV's splitting feature, and including just the audio track. 2. Demuxed to a .dts file using MKVExtractGUI 3. Opened the .dts file in WavePAd (had to tell it to show all files first), then saved as .mp3 Done! Marc

FWIW, with the can read dts files. That way you're not stuck once the free trial runs out.

If you decide to use ffmpeg or AviSynth, extraction is not necessarily needed. I've used a 90min. MKV[H.264+DTS(x3)] file for testing from which I want to extract a 1m:48s section from the 3rd audiostrack starting at 44m:33s. ffmpeg Code: