Re: Wav to Mp3 leads to an mp3 file that has a longer duration

[Martin Ratinaud <martinratinaud@gmail.com>]

[-- Attachment #1.1: Type: text/plain, Size: 2203 bytes --]

Hi Måns and thanks very much

Though it seems the resulting file is 7939544 samples

and 7939544 / 1152 = 6891.965277777777

So it's not a multiple of 1152 unless I'm missing something ?

Cheers

-----------------------------------------------------------------------
*Martin RATINAUD*
-----------------------------------------------------------------------


On Mon, Dec 16, 2019 at 3:48 PM Måns Rullgård <mans@mansr.com> wrote:

> Martin Ratinaud <martinratinaud@gmail.com> writes:
>
> > Hi all,
> >
> > I'm converting a file called vocals.wav to vocals.mp3
> >  vocals.wav
> > <
> https://drive.google.com/file/d/1he1eCJag1G8iGkgL932jy_mXuLT_khGM/view?usp=drive_web
> >
> > For this I'm using this command
> >
> > ```
> > sox vocals.wav vocals.mp3
> > ```
> > and here is the result of the corresponding files
> >
> > - original file
> > ```
> > soxi /Users/martin/Downloads/split-test/vocals.wav
> >
> > Input File     : '/Users/martin/Downloads/split-test/vocals.wav'
> > Channels       : 2
> > Sample Rate    : 44100
> > Precision      : 16-bit
> > Duration       : 00:03:00.00 = 7938000 samples = 13500 CDDA sectors
> > File Size      : 31.8M
> > Bit Rate       : 1.41M
> > Sample Encoding: 16-bit Signed Integer PCM
> > ```
> >
> > - converted file
> > ```
> > soxi /Users/martin/Downloads/split-test/vocals.mp3
> >
> > Input File     : '/Users/martin/Downloads/split-test/vocals.mp3'
> > Channels       : 2
> > Sample Rate    : 44100
> > Precision      : 16-bit
> > Duration       : 00:03:00.04 = 7939544 samples = 13502.6 CDDA sectors
> > File Size      : 2.88M
> > Bit Rate       : 128k
> > Sample Encoding: MPEG audio (layer I, II or III)
> > ```
> >
> > You can see that the duration is not the same which is weird and the
> number
> > of samples also changed.
> > In fact, 1544 samples have been added to the beginning of the file
> >
> > If I try to launch `sox -V vocals.mp3 vocals-trimmed.mp3 trim 1544s` it
> > does not work
>
> MP3 files have to have a multiple of 1152 samples.  This can't be
> avoided.  If the input isn't such a multiple, it will be padded by the
> encoder.
>
> --
> Måns Rullgård
>

[-- Attachment #1.2: Type: text/html, Size: 3400 bytes --]

[-- Attachment #2: Type: text/plain, Size: 0 bytes --]



[-- Attachment #3: Type: text/plain, Size: 158 bytes --]

_______________________________________________
Sox-users mailing list
Sox-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/sox-users