how to extract lossless audio from an MKV file - ffmpeg fails

[batemanj]

Hi,

I have an MKV file (remux from a Bluray) and it's Media info is pasted below. I need to extract the audio lossless with .m4a and/or encode just the audio with quicktime AAC (qaac.exe). I tried ffmpeg to extract but it throws error "Could not find tag for codec dts in stream #0".

Please advise, thanks!!

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, RefFrames : 4 frames
Format settings, GOP : M=3, N=12
Codec ID : V_MPEG4/ISO/AVC
Duration : 2 min 50 s
Bit rate mode : Constant
Bit rate : 35.0 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
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) : 0.703
Stream size : 693 MiB (87%)
Default : Yes
Forced : No

Audio
ID : 2
Format : DTS XLL
Format/Info : Digital Theater Systems
Commercial name : DTS-HD Master Audio
Codec ID : A_DTS
Duration : 2 min 50 s
Bit rate mode : Variable
Bit rate : 4 877 kb/s
Channel(s) : 6 channels
Channel layout : C L R Ls Rs LFE
Sampling rate : 48.0 kHz
Frame rate : 93.750 FPS (512 SPF)
Bit depth : 24 bits
Compression mode : Lossless
Delay relative to video : 91 ms
Stream size : 98.9 MiB (12%)
Title : DTS-HD MA 5.1
Language : Hindi
Default : Yes
Forced : No

[sneaker]

To convert the DTS to AAC using ffmpeg:

ffmpeg -i "input.mkv" -map 0:a:0 "output.m4a"

To convert the DTS to AAC using ffmpeg while keeping video and mkv container:

ffmpeg -i "input.mkv" -map 0 -c:v copy -c:a aac "output.mkv"

To convert audio to AAC using qaac:

ffmpeg -i "input.mkv" -map 0:a:0 -f wav - | qaac - -o "output.m4a"

[batemanj]

Thanks a lot sneaker that worked great...

As I need 448k AAC, I ran the below which worked fine:

ffmpeg -i MyVideo.mkv -map 0:a:0 -f wav - |qaac64 -i -c 448k - -o output448.m4a

is there any better way to do OR my command just fine?

Thanks again.