how to select one audio track when multiple audio tracks are there in a media file using mpv?

Question

I have had media files (video + audio) which have more than one audio track. Sharing an example below -

 $ mediainfo somefile.mkv

General
Unique ID                                : xxxxxxxxxxxxxxxxxxxxxxxx
Complete name                            : somefile.mkv
Format                                   : Matroska
Format version                           : Version 4 / Version 2
File size                                : 1.35 GiB
Duration                                 : 2h 26mn
Overall bit rate                         : 1 314 Kbps
Movie name                               : somefile
Encoded date                             : UTC 2016-09-04 00:00:15
Writing application                      : mkvmerge v8.8.0 ('Wind at my back') 64bit
Writing library                          : libebml v1.3.3 + libmatroska v1.4.4
Cover                                    : Yes
Attachments                              : Cover.jpg

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : [email protected]
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 4 frames
Codec ID                                 : V_MPEG4/ISO/AVC
Duration                                 : 2h 26mn
Bit rate                                 : 1 024 Kbps
Width                                    : 1 280 pixels
Height                                   : 544 pixels
Display aspect ratio                     : 2.35:1
Frame rate mode                          : Constant
Frame rate                               : 24.000 fps
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.061
Stream size                              : 1.05 GiB (78%)
Title                                    : somefile
Writing library                          : x264 core 142 r2479 dd79a61
Encoding settings                        : cabac=1 / ref=3 / deblock=1:-1:-1 / analyse=0x3:0x113 / me=umh / subme=10 / psy=1 / psy_rd=0.00:0.00 / mixed_ref=1 / me_range=32 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=0 / chroma_qp_offset=0 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=8 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=60 / rc=2pass / mbtree=1 / bitrate=1024 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:1.00
Language                                 : Tamil
Default                                  : Yes
Forced                                   : No

Audio #1
ID                                       : 2
Format                                   : AC-3
Format/Info                              : Audio Coding 3
Format profile                           : Dolby Digital
Mode extension                           : CM (complete main)
Format settings, Endianness              : Big
Codec ID                                 : A_AC3
Duration                                 : 2h 26mn
Bit rate mode                            : Constant
Bit rate                                 : 224 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 KHz
Frame rate                               : 31.250 fps (1536 spf)
Compression mode                         : Lossy
Stream size                              : 235 MiB (17%)
Title                                    : somefile
Language                                 : Hindi
Default                                  : Yes
Forced                                   : No

Audio #2
ID                                       : 3
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : HE-AAC / LC
Codec ID                                 : A_AAC
Duration                                 : 2h 26mn
Bit rate                                 : 64.0 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 KHz / 24.0 KHz
Frame rate                               : 23.438 fps (1024 spf)
Compression mode                         : Lossy
Stream size                              : 67.1 MiB (5%)
Title                                    : somefile
Language                                 : Tamil
Default                                  : No
Forced                                   : No

I have taken out the uniqueid and the name of the media file for privacy as well as not needed reasons. As can be seen by the mediainfo there are two audio tracks, one Hindi and the other Tamil. By default, it will take the hindi track as that is the default, but what if I want the Tamil track. How can I play this ?

Solution

MPV provides --aid, from the manual:

--aid=<ID|auto|no>
       Select audio track. auto selects the default, no disables audio.  See  also  --alang.  mpv  normally  prints
       available audio tracks on the terminal when starting playback of a file.

So yeah --aid=1 will be Hindi and --aid=2 will be Tamil.

The is also --alang which should be capable to recognize language codes:

• --alang=hin should play Hindi if such a track is available
• --alang=tam should play Tamil if Tamil is available
• And --alange=tam,hin should play Tamil is available, and if not available shall try to find a Hindi track.

Notes:

• ffprobe will print the language codes (just like mediainfo prints the full langauge).
• There are also --sid and --slang for subtitles.

Comments

[grochmal]

Does # switch between the audio tracks? (i.e. while playing with mpv)

[shirish]

it does, but that doesn't solve my query as I want to do it via CLI and not by a switch, although good tip in itself.

[Admin]

It's clearly a question about CLI, but the GUI (balloon-shaped) button is worth mentioning too.