playing/convert AIFF and AIFC files: interest anyone ?

[Lars]

Hi,

AIFF and AIFC are sound formats that were invented by Apple (I think) for the original MAC and the Apple IIe in 1989 or so.
They resemble WAV files but all meta/header info and data is saved in big endian format (because the Motorola CPU used back at the time was a big endian CPU).

Because I was bored, I am currently working on an IOProc to transform these files into the standard WAV format that MMPM understands. Currently I can read (play) AIFF files in 8-bit,16-bit,24-bit and 32-bit sample size (the data as such is plain PCM data, that is: uncompressed) and uncompressed AIFC files in 8-bit,16-bit,24-bit and 32-bit sample size. I plan to add support for A-law and Mu-law for AIFC.

In theory, OS/2 should already support AIFF, but the IOProc (aiffproc.dll) is broken in that it only endian converts the meta/header data but forgets to endian convert the sound data ...

Is there any interest in this ? Is there also an interest to transform WAV files to the AIFF and/or AIFC formats ?

Cheers,
Lars

[David McKenna]

Hi Lars,

  I would be interested, transformation too. I also occasionally get *.m4a files (also an Apple format, I think iPhones use it) that would be nice to have on the WPS.

Regards,

[Lars]

Hi David,

.m4a is a different format from AIFF or AIFC, it's sound data compressed with MPEG-4 (and not uncompressed PCM data) and also much newer than AIFF and AIFC. I fear that is above my skill level.

AIFF and AIFC sample sound files can be found here:
https://www.mmsp.ece.mcgill.ca/Documents/AudioFormats/AIFF/Samples.html

That's the files I currently test with.

[Remy]

Hi,

AIFF and AIFC are sound formats that were invented by Apple (I think) for the original MAC and the Apple IIe in 1989 or so.
They resemble WAV files but all meta/header info and data is saved in big endian format (because the Motorola CPU used back at the time was a big endian CPU).

Because I was bored, I am currently working on an IOProc to transform these files into the standard WAV format that MMPM understands. Currently I can read (play) AIFF files in 8-bit,16-bit,24-bit and 32-bit sample size (the data as such is plain PCM data, that is: uncompressed) and uncompressed AIFC files in 8-bit,16-bit,24-bit and 32-bit sample size. I plan to add support for A-law and Mu-law for AIFC.

In theory, OS/2 should already support AIFF, but the IOProc (aiffproc.dll) is broken in that it only endian converts the meta/header data but forgets to endian convert the sound data ...

Is there any interest in this ? Is there also an interest to transform WAV files to the AIFF and/or AIFC formats ?

Cheers,
Lars

Hi Lars,

Into my local avxcat beta, I added AIFF since several months yet and the result is very good.
The big advantage of AIFF is that it allow metadatas as well included albumart
(WAV could have them too but not all players are able to extract wav metadatas and/or embebbed front cover)

I put my AIFF as well WAV and FLAC on my high-end streamer/server connected to a high-end DAC.
Aiff provides a better sound than WAV or FLAC while all are losness ! surprising
Logically AIFF and WAV should be same due AIFF is the Aplle format for WAV but out of the High end speakers, AIFF is a litle above (may be due streamer/server integreated converter or less jitter ! I don't know yet)

AIFF is my prefered despite I have no apple system.
WAV and FLAC are providing nearly the same result.

Regards
Rémy

note: I never go above 24bits resolutions (it improves signal on noise ratio)         
          ffmpeg handle it well. (Didn't find any interest to push up to 32bits) 

[Lars]

The reason I was developing an IOProc is so that you can just double click a sound file to have it play (you do not need an application). Plus, if translation works both ways, you can convert to/from AIFF and AIFC respectively.

I would not know why AIFF would sound any better compared to WAV, provided the very same sample rate and bit depth is chosen (and the very same analog sound source material, of course). The data is exactly the same in both cases (it's plain PCM data). WAV saves it as little endian, AIFF saves it as big endian.

[Dave Yeo]

Preserving the metadata is another consideration, though it may not be currently preserved. Flac and ogg should also preserve the metadata, even when converting.

[Remy]

The reason I was developing an IOProc is so that you can just double click a sound file to have it play (you do not need an application). Plus, if translation works both ways, you can convert to/from AIFF and AIFC respectively.

I would not know why AIFF would sound any better compared to WAV, provided the very same sample rate and bit depth is chosen (and the very same analog sound source material, of course). The data is exactly the same in both cases (it's plain PCM data). WAV saves it as little endian, AIFF saves it as big endian.

Been able to play AIFF under OS/2 is helpfull to check audio files quality and of course play audio under OS/2.
With USB audio, it may be nice to play audio files out of usb to a dac

e.g. ffprob of a wav track I just converted to AIFF including metadatas and front cover
        If this could be helpfull !

          Metadata:
    genre           : Chanson
    album           : Le bal des oiseaux
    artist          : Thomas Fersen
    title           : Juillet
    track           : 3
    date            : 1993
    encoder         : Lavf58.29.100
  Duration: 00:03:04.80, start: 0.000000, bitrate: 4625 kb/s
    Stream #0:0: Audio: pcm_s24be, 96000 Hz, 2 channels, s32 (24 bit), 4608 kb/s

    Stream #0:1: Video: png, rgb24(pc), 500x500 [SAR 1:1 DAR 1:1], 90k tbr, 90k
tbn, 90k tbc (attached pic)
    Metadata:
      title           : Album cover
      comment         : Cover (front)