I am right in thinking mp2 audio is 48000hz? I know CD audio is 44100hz 16
bit so I assume the filesize of the wav would be lower than the mp2 and also
of a lower quality?
Also, I've heard the Nebula DigiTV isn't exactly brilliant at recording mp2
can anyone confirm this?
Cheers,
Paul
The quality depends on how well you convert to 44.1kHz, avoid on-the-fly
conversion and use something like Cool Edit.
As for filesize, the raw .wav will be over 8 times larger because the mp2 is
compressed.
Az.
You'll need software that can open mp2 files and allow them to be saved as a
wav file. TMPGEnc can do this, but there are others out there.
> I am right in thinking mp2 audio is 48000hz? I know CD audio is 44100hz 16
> bit
Yes. The previously mentioned software will also need to sample rate convert
to 44.1kHz. Again, TMPGEnc can do this.
>so I assume the filesize of the wav would be lower than the mp2
No. A wav file is a linear file, an mp2 file is compressed. As a rough
rule-of -thumb, a wav file uses about 10MB per minute of stereo audio.
> and also of a lower quality?
The quality can only be as good as the weakest link in the chain. The weak
link is mp2, so converting to wav won't improve on that, but won't make it
worse either (assuming the quality of the mp2-wav conversion isn't suspect,
of course).
"DB" <db_...@hotmail.com> wrote in message
news:bdd0vo$r4j5m$1...@ID-173811.news.dfncis.de...
You can use many things to decode mp2 audio, most of them free. The
two I usually use are Winamp (setting the output to the diskwriter
plug-in - included in the standard Winamp install) and the LAME mp3
encoder, which will happily decode mp1, mp2, and mp3 using the
--decode command line.
For resampling, Cool Edit is what I use - quality 256, pre/post
filtering on.
However, there's a free option called SSRC which is equally good.
(Better, in some respects).
For this kind of encoding/decoding/resampling etc there's a front-end
for many popular tools called "BeSweet" available from here:
http://dspguru.notrace.dk/
It's designed to handle the needs of the video hackers, encoders +
traders out there, but it's great for pure audio work. It's a bit
intimidating because there's so much in there, but click a few buttons
and you'll find what you want!
Hope this helps.
Cheers,
David.
Do you have Nero burning software? This has a hidden feature. If select to
make an audio cd and pick mp3 files it converts them. I presume the same
with mp2.
Paul
"Aztech" <a...@tech.com> wrote in message
news:2CnKa.6339$j97.44...@news-text.cableinet.net...
Not sure whether it's the same in Cool Edit, but in Cool Edit Pro on the
File menu there is an option to Extract Audio from Video. Using this option
allows mp2 files to be opened (even when you're not extracting audio from
video).
paul
"DB" <db_...@hotmail.com> wrote in message
news:bdjkaa$tv36q$1...@ID-173811.news.dfncis.de...
I don't know, I've only ever used this feature for opening audio files
recorded from DAB. It may be that you need to run it through PVAStrumento
first to ensure it's in proper mp2 format.
I would recommend getting hold of CoolPlayer if you are using Windows.
It is an soundfile player that does MP3 and the like, and is based
around the madlib MPEG decoder. This seems to do the best job of
turning the Freeview MP2's into wave files.
My experience is that CoolEdit 2000 takes forever to resample from
48kHz to 44.1kHz, and that I use the ResampAudio program out of
the AFsp suite of programs which does just as good a job (if not better)
and is a lot faster due to the lack of GUI getting in the way. I
can also script it up to convert a bunch of files at once. See the
URL below for more information.
http://www.tsp.ece.mcgill.ca/MMSP/Documents/Software/AFsp/ResampAudio.html
JAB.
--
Jonathan A. Buzzard Email: jonathan at buzzard.me.uk
Northumberland, United Kingdom. Tel: +44 1661-832195
There's a good reason for that, you don't get something for nothing.
Az.
Not really, the process is handled somewhat inefficiently in CoolEdit.
To start with when you finish you still have to save the file, and
it does an undo backup before you start. ResampAudio reads the file
in and spits another copy out, and immediate overhead saving.
The algorithms employed by ResampAudio are the same as used by
CoolEdit 2000, and you have much more control of the parameters if
you want as well.
> ResampAudio reads the file
> in and spits another copy out, and immediate overhead saving.
>
> The algorithms employed by ResampAudio are the same as used by
> CoolEdit 2000, and you have much more control of the parameters if
> you want as well.
The bit about "same algorithms" is a bold statement! Reading the link
you gave:
http://www.tsp.ece.mcgill.ca/MMSP/Documents/Software/AFsp/ResampAudio.html
I don't know if what you say is true, because the methods used within
Cool Edit are not published - are they?
FWIW no one seems to have picked up on my first reply
http://groups.google.com/groups?dq=&hl=en&lr=&ie=UTF-8&oe=UTF-8&selm=cd71db10.0306260032.234faaf9%40posting.google.com
...where I suggested SSRC (
http://www.doom9.org/index.html?/software2.htm scroll down) which
really is equally as good as Cool Edit, but free.
Cheers,
David.
[SNIP]
>>
>> The algorithms employed by ResampAudio are the same as used by
>> CoolEdit 2000, and you have much more control of the parameters if
>> you want as well.
>
> The bit about "same algorithms" is a bold statement! Reading the link
> you gave:
> http://www.tsp.ece.mcgill.ca/MMSP/Documents/Software/AFsp/ResampAudio.html
> I don't know if what you say is true, because the methods used within
> Cool Edit are not published - are they?
Well we don't know for sure, but this is a well understood area of DSP.
There is therefore unlikely to be any black magic going on in CoolEdit.
The algorithms in ResampAudio are high quality algorithms, and judging
by the limited amount twiddling you can do with the CoolEdit algorithms
they are at least very similar.
For this reason I use TotalRecorder and record directly to MP3.
Mart
"wowfabgroovy" <wowfab...@wowmail.com> wrote in message
news:3f0c44b7...@news.easynews.com...
> "Paul" <1231878S...@btinternet.com> went:
>
> >Also, I've heard the Nebula DigiTV isn't exactly brilliant at recording
mp2
> >can anyone confirm this?
>
> there is something non-standard about the mp2 files created by digitv.
> mannsmp3edit spits them out, and razorlame/lame frequently crashes
> when converting them to mp3. i don't know what it is that makes them
> non-standard, but files created by a nova-t don't have this problem.
>
>
> --
> warning -- bbc radio 4 is broadcast in mono most of the day
> on dab digital radio and bbc7 is mono all day.
I really should polish it off, but I have written some C code
that strips this extra crap out. Works a treat. The biggest
problem is that it needs to scan the first hundred or so frames
and calculate the correct frame parameters rather than have
those for BBC7 hardcoded into the program.