[alsa-devel] Question about Conversion to S24_LE from S24_3LE

[Clemens Ladisch]

Fujikawa, Kazutoshi wrote:
>>> 0x00123456 (MSB 0(or 0xFF) padding)
>>
>> This is the correct S24_LE representation.
>
> I record a sound file by arecord command on Ubuntu.
> (% arecord -f S24_LE -r 48000 -c 2 ubuntu_rec_S24_LE_48000.wav )
>
> Then this file was created, and it was LSB 0 padding.
> So I think that S24_LE format is LSB 0 padding.
>
> % od -t x4 ubuntu_rec_S24_LE_48000.wav
> 0000000 46464952 003a9824 45564157 20746d66
> 0000010 00000010 00020001 0000bb80 0005dc00
> 0000020 00180008 61746164 003a9800 ffffbf00
> 0000030 ffffc300 ffffc600 ffffca00 ffffd300
> 0000040 ffffd600 ffffdc00 ffffe000 ffffe000
> 0000050 ffffe400 ffffea00 ffffeb00 fffff800
> 0000060 fffffa00 00000400 00000500 00001000
> 0000070 00000f00 00001600 00001700 00001500
>
> Do you know why this file is LSB 0 padding?

What hardware (driver) was this recorded from?
Does the hardware actually support S24_LE, or was this converted?


Regards,
Clemens