[Marc[_5_]]

Hi,
I would like to be able to use the "rewind" function when playing
audio files in windows xp. I recorded some lectures with my Zoom H2
and would like to be able to rewind the lectures when I miss
something. I would like to do this with my Keyspan remote control from
a distance without having to get up everytime to move the slider back.
I tried using windows media player to do this, but there is no rewind
function (it's greyed out). Do audio software exist which provide the
"rewind" button when playing mp3,.wav, or any other kind of audio
files.

Thanks alot,
Marc

[Eeyore]

Soundhaspriority wrote:

"Marc" wrote in message

Hi,
I would like to be able to use the "rewind" function when playing
audio files in windows xp. I recorded some lectures with my Zoom H2
and would like to be able to rewind the lectures when I miss
something. I would like to do this with my Keyspan remote control from
a distance without having to get up everytime to move the slider back.
I tried using windows media player to do this, but there is no rewind
function (it's greyed out). Do audio software exist which provide the
"rewind" button when playing mp3,.wav, or any other kind of audio
files.

In your title, you ask "why", so here's an explanation. There are two
reasons:

1. MPEG is very clever; it records two different types of data. An "iframe"
is a snapshot of the wave, and a "jframe" is an incremental difference,
which takes much less storage than the information in the iframe. Every so
many frames, a new iframe is written. If there were a rewind buttom, the
software would have to interpret jframes that require a jframe many frames
back, plus all the iframes leading up to this point. A software program that
responsively implements a rewind buttom would require a very fast processor.

I have not looked at the computational load of doing this, so I do not have
a definitive answer as to whether it can actually be done. Certainly,
dedicated chips could provide this functionality. But since mpeg is a
"delivery medium", not an "editing medium", the conventional pov is that
what you want is not widely desired.

2. A flash based recorder has a little OS inside it, and it creates files.
All of the computer OSes in the world are designed to read files in the
forward direction. Even when a compiler library seems to provide "random
access", it's really a simulation. In order to natively read files
backwards, a recorder would have to maintain files as a doubly linked list.
This could be done, but the FAT file system, which so conveniently allows
flash to be read by recorders and all kinds of computers, could not be used.
It would have to be a proprietary file system. Nevertheless, programs do
exist, typically DAW editors, that allow "scrubbing" an audio timeline
representing WAV files in both directions. The complexity has resulted in
the omission of this feature in "players."

Interesting explanation Bob. I'd never really stopped to think about it before.

Obviously not a problem with wav files. And as semiconductor and other memory
grows, maybe mp3's time will one day be finished.

Graham

[Marc[_5_]]

On Oct 19, 3:06*pm, "Soundhaspriority" wrote:
"Marc" wrote in message

...

Hi,
I would like to be able to use the "rewind" function when playing
audio files in windows xp. I recorded some lectures with my Zoom H2
and would like to be able to rewind the lectures when I miss
something. I would like to do this with my Keyspan remote control from
a distance without having to get up everytime to move the slider back.
I tried using windows media player to do this, but there is no rewind
function (it's greyed out). Do audio software exist which provide the
"rewind" *button when playing mp3,.wav, or any other kind of audio
files.

Thanks alot,
Marc

In your title, you ask "why", so here's an explanation. There are two
reasons:

1. MPEG is very clever; it records two different types of data. An "iframe"
is a snapshot of the wave, and a "jframe" is an incremental difference,
which takes much less storage than the information in the iframe. Every so
many frames, a new iframe is written. If there were a rewind buttom, the
software would have to interpret jframes that require a jframe many frames
back, plus all the iframes leading up to this point. A software program that
responsively implements a rewind buttom would require a very fast processor.

I have not looked at the computational load of doing this, so I do not have
a definitive answer as to whether it can actually be done. Certainly,
dedicated chips could provide this functionality. But since mpeg is a
"delivery medium", not an "editing medium", the conventional pov is that
what you want is not widely desired.

2. A flash based recorder has a little OS inside it, and it creates files..
All of the computer OSes in the world are designed to read files in the
forward direction. Even when a compiler library seems to provide "random
access", it's really a simulation. In order to natively read files
backwards, a recorder would have to maintain files as a doubly linked list.

[philicorda[_6_]]

On Sun, 19 Oct 2008 15:06:51 -0400, Soundhaspriority wrote:

"Marc" wrote in message
news:55977b22-b103-438a-afba-
...
Hi,
I would like to be able to use the "rewind" function when playing audio
files in windows xp. I recorded some lectures with my Zoom H2 and would
like to be able to rewind the lectures when I miss something. I would
like to do this with my Keyspan remote control from a distance without
having to get up everytime to move the slider back. I tried using
windows media player to do this, but there is no rewind function (it's
greyed out). Do audio software exist which provide the "rewind" button
when playing mp3,.wav, or any other kind of audio files.

Thanks alot,
Marc

In your title, you ask "why", so here's an explanation. There are two
reasons:

1. MPEG is very clever; it records two different types of data. An
"iframe" is a snapshot of the wave, and a "jframe" is an incremental
difference, which takes much less storage than the information in the
iframe. Every so many frames, a new iframe is written. If there were a
rewind buttom, the software would have to interpret jframes that require
a jframe many frames back, plus all the iframes leading up to this
point. A software program that responsively implements a rewind buttom
would require a very fast processor.

I'm not sure this is true.
MP3 does have frames, but they are quite small and don't work in the same
way as video. I don't think it has iframes and jframes. The encoding is
not an incremental change from a waveform snapshot, that would make sense
for lossless compression, but not for lossy.
You can cut an mp3 on a frame boundary and it will play fine, regardless
of what came before.
I'm not 100% on this, it's just that your explanation feels wrong to me.
Clarification is welcomed!


I have not looked at the computational load of doing this, so I do not
have a definitive answer as to whether it can actually be done.
Certainly, dedicated chips could provide this functionality. But since
mpeg is a "delivery medium", not an "editing medium", the conventional
pov is that what you want is not widely desired.

I've been playing with a program called 'mixxx' it lets you reverse,
rewind, or even scratch MP3s using timecode from a physical vinyl record.
It's probably rendering the active part of the mp3 into memory as
uncompressed audio on the fly though.

FF and RW takes about 40% of a 2GHz Athlon XP, so like you say this would
probably be impractical for a portable device.


2. A flash based recorder has a little OS inside it, and it creates
files. All of the computer OSes in the world are designed to read files
in the forward direction. Even when a compiler library seems to provide
"random access", it's really a simulation. In order to natively read
files backwards, a recorder would have to maintain files as a doubly
linked list. This could be done, but the FAT file system, which so
conveniently allows flash to be read by recorders and all kinds of
computers, could not be used. It would have to be a proprietary file
system. Nevertheless, programs do exist, typically DAW editors, that
allow "scrubbing" an audio timeline representing WAV files in both
directions. The complexity has resulted in the omission of this feature
in "players."

Bob Morein
(310) 237-6511

[Richard Crowley]

"Soundhaspriority" wrote ...
In your title, you ask "why", so here's an explanation. There are two
reasons:

1. MPEG is very clever; it records two different types of data. An
"iframe" is a snapshot of the wave, and a "jframe" is an incremental
difference, which takes much less storage than the information in the
iframe. Every so many frames, a new iframe is written. If there were a
rewind buttom, the software would have to interpret jframes that require a
jframe many frames back, plus all the iframes leading up to this point. A
software program that responsively implements a rewind buttom would
require a very fast processor.

I have not looked at the computational load of doing this, so I do not
have a definitive answer as to whether it can actually be done. Certainly,
dedicated chips could provide this functionality. But since mpeg is a
"delivery medium", not an "editing medium", the conventional pov is that
what you want is not widely desired.

2. A flash based recorder has a little OS inside it, and it creates files.
All of the computer OSes in the world are designed to read files in the
forward direction. Even when a compiler library seems to provide "random
access", it's really a simulation. In order to natively read files
backwards, a recorder would have to maintain files as a doubly linked
list. This could be done, but the FAT file system, which so conveniently
allows flash to be read by recorders and all kinds of computers, could not
be used. It would have to be a proprietary file system. Nevertheless,
programs do exist, typically DAW editors, that allow "scrubbing" an audio
timeline representing WAV files in both directions. The complexity has
resulted in the omission of this feature in "players."

While those are both interesting theories, I don;t think that either
of them is a show-stopper in real life. Any software smart enough
to decode MP3 in real-time is ipso-facto smart enough to find the
nearest "iframe". Regardless of which direction or speed.

I think there are two more fundamental reasons...

1) "Perhaps makers of free and low-cost players don't include
the function perhaps as a distinguishing feature from their higher-
end wares.

2) What exactly does "rewind' mean/do in a non-linear world?
There are almost as many different notions of what "Rewind"
should do as there are implementations of it. Should it start
playing backwards (emulating tape)? At what speed should
it run? For how long? Should it skip back some fixed amount
of time? How long? Should it be proportional to the length of
the clip? Should it go back to the beginning of the clip?
There have been situations where I wanted each of those
different functionality, but AFAIK, there are NO applications
that allow you to specify any of the parameters of "Rewind"
if it is even supported at all.

[Nil]

On 19 Oct 2008, Marc wrote in
rec.audio.pro:

Do audio software exist which provide the "rewind" button when
playing mp3,.wav, or any other kind of audio files.

iTunes does, Winamp does, Foobar2000 does. iPod does, my old Archos mp3
player does. I think most software and hardware players do. I don't
know why WMP doesn't, but this is just one more reason I won't touch
it.

[Richard Crowley]

"Nil" wrote ...
Marc wrote in :
Do audio software exist which provide the "rewind" button when
playing mp3,.wav, or any other kind of audio files.

.... iPod does,

Then perhaps you should describe what YOU mean by "rewind button"?

This was exactly my point about the definition being ambiguous in
the non-linear world.

[Nil]

On 20 Oct 2008, "Richard Crowley" wrote in
rec.audio.pro:

Then perhaps you should describe what YOU mean by "rewind button"?

Why should I do that? That wasn't the question. He asked why audio file
players don't have a rewind function and I mentioned some that do. But
FYI, the rewind button in all the examples I cited make the music back
up, much like the rewind control on a tape machine.

[gareth magennis]

"Nil" wrote in message
...
On 20 Oct 2008, "Richard Crowley" wrote in
rec.audio.pro:

Then perhaps you should describe what YOU mean by "rewind button"?

Why should I do that? That wasn't the question. He asked why audio file
players don't have a rewind function and I mentioned some that do. But
FYI, the rewind button in all the examples I cited make the music back
up, much like the rewind control on a tape machine.


Winamp doesn't do that at all. It doesn't have a rewind button, just the
cursor bar which you can pick up and move back. It will jump back to a
place determined by Winamp, fade out the music playing and then fade in from
the new selected point. Thats not a rewind button at all.


Gareth.

[Richard Kuschel]

On Oct 19, 3:49*pm, "Soundhaspriority" wrote:
"Richard Crowley" wrote in message

. ..

"Soundhaspriority" wrote ...
In your title, you ask "why", so here's an explanation. There are two
reasons:

1. MPEG is very clever; it records two different types of data. An
"iframe" is a snapshot of the wave, and a "jframe" is an incremental
difference, which takes much less storage than the information in the
iframe. Every so many frames, a new iframe is written. If there were a
rewind buttom, the software would have to interpret jframes that require
a jframe many frames back, plus all the iframes leading up to this point.

[Arny Krueger]

"Marc" wrote in message


I would like to be able to use the "rewind" function when
playing audio files in windows xp.

Rewind means going back to the beginning of the file. Most players will do
this if you hit the stop, rather than the pause button.

I recorded some
lectures with my Zoom H2 and would like to be able to
rewind the lectures when I miss something.

Oh, you want a backspace function.

I would like
to do this with my Keyspan remote control from a distance
without having to get up everytime to move the slider
back.

Your remote control is deficient in that it won't control a very important
control, the slider.

I tried using windows media player to do this, but
there is no rewind function (it's greyed out).

When a control is present but greyed out, this is nature's way of telling
you that the codec for the particular kind of media being played did not
implement the function. These days media players are train stations, not
trains. They are incomplete all by themselves - they are dependent on other
programs that they find dynamically when they try to open the file you want
to play.

Playing media on a computer is actually chaotic and uncontrolled. You don't
know for sure what software actually plays a file without some detailed
analysis. Furthermore, its not just one piece of software in many cases, but
a stack of different pieces of software.


Do audio
software exist which provide the "rewind" button when
playing mp3,.wav, or any other kind of audio files.

Other posters have pointed out a number of players that have some kind of
backspace function. But you're right, this feature is very convenient and
often not implemented.

[Jos Geluk]

Gareth Magennis schreef:
"Nil" wrote in message
...
On 20 Oct 2008, "Richard Crowley" wrote in
rec.audio.pro:

Then perhaps you should describe what YOU mean by "rewind button"?
Why should I do that? That wasn't the question. He asked why audio file
players don't have a rewind function and I mentioned some that do. But
FYI, the rewind button in all the examples I cited make the music back
up, much like the rewind control on a tape machine.


Winamp doesn't do that at all. It doesn't have a rewind button, just the
cursor bar which you can pick up and move back. It will jump back to a
place determined by Winamp, fade out the music playing and then fade in from
the new selected point. Thats not a rewind button at all.

Pressing the left and right arrow keys will rewind or fast forward by 5
seconds. True, there is no corresponding button on the screen.

Jos.

--
Ardis Park Music
www.ardispark.nl

[Mike Rivers]

Marc wrote:
I would like to be able to use the "rewind" function when playing
audio files in windows xp. I recorded some lectures with my Zoom H2
and would like to be able to rewind the lectures when I miss
something.

The H2 is meant to be a recorder, with the intent that you'll copy the
file to something else and play it back there, other than to do a quick
check to see that you've recorded something. I believe that you'll find
the "jump back a bit" button on recorders that are meant for recording
speech rather than music, and anticipate that the program will be played
back on the recorder. What you want is a "memo" recorder, not a music
recorder like the Zoom H2.

Manufacturers have to choose the features that they incorporate into a
product in order to both limit their cost and not make it too
complicated for what they think will be the target user. The way the
user interface on the H2 is designed, it would almost be necessary to
add another button to provide the "rewind" function. You wouldn't want
to have to go to a menu for it.

I haven't gone through the full feature set yet, but if you want that
feature as well as having a decent music recorder, you might look at
TASCAM's new version of their handy recorder that's designed to be a
guitarist's learning and working tool. It incorporates many of TASCAM's
"trainer" functions, so it might be able to quickly jump back and repeat
a section.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Nil]

On 20 Oct 2008, "Gareth Magennis"
wrote in rec.audio.pro:

Winamp doesn't do that at all. It doesn't have a rewind button,
just the cursor bar which you can pick up and move back. It will
jump back to a place determined by Winamp, fade out the music
playing and then fade in from the new selected point. Thats not a
rewind button at all.

OK, you're right, I misremembered, there is no button. However, I
always use the left and right arrow keys, which will fast-forward and
rewind the file.

[Mike Rivers]

On 20 Oct 2008, "Gareth Magennis"
wrote in rec.audio.pro:

Winamp doesn't do that at all. It doesn't have a rewind button,
just the cursor bar which you can pick up and move back.

I use MP3 Direct Cut now and then and it has buttons to jump back and
forward by preset times. Kind of handy when I decide that the place to
cut the file is 20 or 30 seconds ago.

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[Richard Crowley]

"Nil" wrote ...
, "Gareth Magennis" wrote :
Winamp doesn't do that at all. It doesn't have a rewind button,
just the cursor bar which you can pick up and move back. It will
jump back to a place determined by Winamp, fade out the music
playing and then fade in from the new selected point. Thats not a
rewind button at all.

OK, you're right, I misremembered, there is no button. However, I
always use the left and right arrow keys, which will fast-forward and
rewind the file.

You misremembered about iPod as well. There is no "rewind"
function, button, or control on a standard iPod user interface.

There is a button/function to skip back to the beginning of the
file. And the same button will skip back to the previous file.
There is also a slew function where you can position the read
point within the file (in either direction). But neither of these
functions can be called "rewind" with any expectation that an
audio professional would recognize.

This is exactly what I meant by no definition of "rewind" in the
non-linear world. "Nil" illustrates perfectly what I'm saying.

[Nil]

On 20 Oct 2008, "Richard Crowley" wrote in
rec.audio.pro:

You misremembered about iPod as well. There is no "rewind"
function, button, or control on a standard iPod user interface.

There is a button/function to skip back to the beginning of the
file. And the same button will skip back to the previous file.
There is also a slew function where you can position the read
point within the file (in either direction). But neither of these
functions can be called "rewind" with any expectation that an
audio professional would recognize.

First of all, "audio professional" has nothing to do with it. Second,
yes there is: pressing and releasing the left arrow on an iPod will
rewind the file to the beginning. Pressing and holding the left arrow
button on an iPod will rewind the audio file to any earlier point
within the file. That is what the original poster was asking about.

What's with the snotty attitude?

[Richard Crowley]

"Nil" wrote ...
First of all, "audio professional" has nothing to do with it. Second,
yes there is: pressing and releasing the left arrow on an iPod will
rewind the file to the beginning. Pressing and holding the left arrow
button on an iPod will rewind the audio file to any earlier point
within the file. That is what the original poster was asking about.

What's with the snotty attitude?

Perhaps you are too young to remember what "rewind" meant
back in the days of physical tape. OTOH, the ability to skip
back to the beginning of the song, or to the beginning of the previous
(or next) song is something that was only a kludge (at best)
in the era of tape.

[Nil]

On 21 Oct 2008, "Richard Crowley" wrote in
rec.audio.pro:

Perhaps you are too young to remember what "rewind" meant
back in the days of physical tape.

Perhaps you're wrong.

How is 'pressing and holding the iPod's left arrow takes you back to
any earlier part of the file' not a rewind?

[Richard Crowley]

"Nil" wrote ...
How is 'pressing and holding the iPod's left arrow takes you back to
any earlier part of the file' not a rewind?

I stand corrected. You are right. I never held the button down
long enough to encounter the fast-forward/rewind function.
That is as close to old-time tape FF/rew as we are likely to find
in the non-linear era.

[Mike Rivers]

Richard Crowley wrote:

Perhaps you are too young to remember what "rewind" meant
back in the days of physical tape.

How about the videotape rental stores that fined you if you didn't
rewind the tape before returning it? How soon they forget.

OTOH, the ability to skip
back to the beginning of the song, or to the beginning of the previous
(or next) song is something that was only a kludge (at best)
in the era of tape.

Oh, I dunno. There were some pretty sophisticated locators out there,
either designed for a specific machine or capable of learning dynamic
characteristics to brake gently when approaching the locate point and
park in the right place. And several professional tape decks were
equipped with a shuttle control for moving the tape in either direction
quickly, with or without the monkey chatter.

The kludges of which you speak are likely the ones that stop winding
when the counter hit zero and coasting to a stop wherever.

--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)