AES to Wav conversion

[Dave1024]

Hi,

Please help us to find the answers for below qu:

What is the specialty of AES wrapped wave files.?

In which context AES is used ?

Does there any converter is available for AES to Wave?

thanks,
Dave

[foxyshadis]

I think you need to find that out from wherever you got the files, or provide a whole lot more detail. AES is just a generic encryption formula, it can be applied in an infinite number of ways.

[Guest]

It's a standard for digital audio.

http://www.digitalpreservation.gov/formats/fdd/fdd000142.shtml

[Dave1024]

Hi neuron

Does ffmpeg will help me to convert AES audio to PCM audio ?

-Dave

[Guest]

AES is an interface spec not a file spec, I believe. Can you tell us more about the files themselves. How were they made or where did they come from?

[raffriff42]

"AES Audio" normally refers to the over-the-wire digital format (comparable to SPDIF); in a file, AES31-2-2012, Audio file format for interchange (http://www.aes.org/standards/blog/2013/1/aes31-2-2012-file-format-130124) is also known as Broadcast Wave Format (https://en.wikipedia.org/wiki/Broadcast_Wave_Format) which is playable everywhere.

If your file extension is AES, it's possible it's an encrypted file (https://en.wikipedia.org/wiki/Advanced_Encryption_Standard).

EDIT If we are not "getting" what you mean by "AES wrapped WAV file," please supply whatever media info you have; or better yet a sample. (Oh, neuron2 just said that)

[Ghitulescu]

This spec is new, barely one year old, my belief is that Dave1024 wants to copy directly from the AES interface to a file.
With a few minor changes in the subcodes, AES is the same as S/P-DIF.

[SeeMoreDigital]

Does anyone have a short sample?

[raffriff42]

Reading neuron2's link (http://www.digitalpreservation.gov/formats/fdd/fdd000142.shtml#sign) a little more closely, Filename extension:
...Generally depends upon the wrapper used for the "storage" version of LPCM. LPCM data may be stored in "raw" form, with ".raw" as a possible file extension. A variant of this encoding is captured by devices manufactured by Snell and Wilcox, reportedly carring an ".aes" extension.So what can we say about an AES file? LPCM = linear PCM = WAV format. It's limited to 2 channels per the link. Sample rate and bit depth are unknown, but some specs (48000/16, 96000/20, etc) are likelier than others. If ffmpeg can determine the stream type, you can simply remux to WAV: ffmpeg -i "inputfile.raw" -c:a copy "outputfile.wav"
otherwise you will have to tell ffmpeg it is raw audio, and manually specify sample rate, sample type etc. For example (not tested):ffmpeg -f pcm_s16le -ar 44.1k -ac 2 -i "inputfile.raw" "outputfile.wav"

[Dave1024]

Hi All,

Audio
ID : 3
Format : PCM
Format settings, Endianness : Little
Format_Settings_Wrapping : Frame (D-10)
Duration : 30s 30ms
Bit rate mode : Constant
Bit rate : 12.3 Mbps
Channel(s) : 8 channels
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Stream size : 44.0 MiB (20%)

This is the media info of my file. It is a MXF file where audio is D-10 in other words audio is aes. Also video track is present it is IMX D-10.
I will try ffmpeg with commands mentioned by raffriff42.

I am able to extract the file as native format (aes). Does ffmpeg will accept this *.aes file as raw input file and convert it to PCM ?

-Dave

[SeeMoreDigital]

Can you upload it somewhere?

[raffriff42]

Does ffmpeg will accept this *.aes file as raw input file and convert it to PCM ?Probably yes, but probably *not* on the first try. We can help you fix any problems, if we can see the error output from ffmpeg. Please be sure to copy (http://www.sevenforums.com/general-discussion/280269-copy-paste-within-command-window.html#post2307236) the entire output with all error messages and paste in your next reply. (Use the CODE "#" toolbar button please)

[Dave1024]

Hi raffriff42

Track_3.aes: Invalid data found when processing input.

This is the error message given by ffmpeg.

command string :-

ffmpeg.exe -i Track_3.aes -f pcm_s16le -ar 48000 -ac 8 outF.wav

Thanks
Dave

[raffriff42]

I wish you would post the entire output; there is probably more information there that would have helped. Again, can you upload a sample somewhere?

Honestly I don't know! The online information on this is pretty sparse and probably out of date.
Audio
ID : 3
Format : PCM
Format settings, Endianness : Little
Format_Settings_Wrapping : Frame (D-10)
Duration : 30s 30ms
Bit rate mode : Constant
Bit rate : 12.3 Mbps
Channel(s) : 8 channels
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Stream size : 44.0 MiB (20%) I thought 2 channels was the maximum, according to the above source (http://www.digitalpreservation.gov/formats/fdd/fdd000142.shtml).

Another thing: 16bits * 48000 * 8 = 6 Mbps, not 12. What is happening here?

Anyway, try:
ffmpeg.exe -i Track_3.aes -sample_fmt s16 -f pcm_s16le -ar 48000 -ac 8 outF.wav...or maybe s16p (16 bit signed, planar), or something else - type ffpmeg -sample_fmts for a list of all the audio sample formats, tersely explained in the source code (http://ffmpeg.org/doxygen/trunk/samplefmt_8h.html#af9a51ca15301871723577c730b5865c5ac5d4bb5b0fb0dc7316fb3c7a73029912).

[Ghitulescu]

Maybe the audio source is ADAT, this has 48k and 8 channels and still got through digital out.

[Dave1024]

Hi raffriff42

The track info which i mention is displayed by media info.
with the revised command also shows same error messages.

-Dave