[SOLVED] Transfer rate.

stf92 · 07-29-2010, 02:10 PM

Linux kernel 2.6.21.5, Slackware 12.0
File 4.21

Hi:

I've been doing a lot of thinking before I made up my mind to post this question in LQ. Finally, the prevailing argument was the answer would be known to a great deal of LQ members although, I know, I risk the post remaining only a little while in LQ.

Code:

root@darkstar:/mnt/mozart34# file PSO041023_Mozart_Sym34_I.mp3
PSO041023_Mozart_Sym34_I.mp3: MPEG ADTS, layer III, v1, 256 kBits, 44.1 kHz, Stereo
root@darkstar:/mnt/mozart34#

The file command is telling me a certain parameter has value 256 kBits. What is this parameter or, more precisely, what is the name of the parameter? This is the question.

Do not, please, think I've not been doing my homework. I have both googled and wikipediaed, but it was of no use. It is obviously a property of the file. Say I have a WAV file, recorded @44.1kHz, 16bits, mono. Some program compresses it into an MP3 file. If I were to playback the WAV file, then data would have to be reaching the first analog stage at 44.1*16= 705.6 kbps. But, as I mentioned above, I would like to have, if not the definition of that parameter, its name. Any suggestion will be welcome. Thanks for reading.

pixellany · 07-29-2010, 02:47 PM

some suggestions:

1. Read through the man pages on the "file" command for some insight into what data it looks at.

2. If you have an .mp3 file which is legal to distribute, then post it here as an attachment so we can look at it.

3. Use something like hexdump to look at the file for clues. At the same time, Google for info on the mp3 format spec.

dugan · 07-29-2010, 03:07 PM

It looks like the MP3's bitrate.

Sergei Steshenko · 07-29-2010, 05:31 PM

Quote:

Originally Posted by dugan

It looks like the MP3's bitrate.

It is. I.e. it's 256KBits/second.

stf92 · 07-29-2010, 06:11 PM

@pixellany: the man pages on the 'file' command is something I missed. And the MP3 format spec, of course!

Bitrate: I now remember this word. I had quite forgotten. So now I have the answer to my question plus, additional data to allow me to investigate into the definition of bitrate in the context of the file command output when inspecting MP3 files. Thank you very much.