Re: how to record sound to mp3

[Victor A. Stoichita]

Le 25 Mar 2021, Nicolas George  a écrit :
I am quite sure (and certain in the case of FFmpeg) that none of 
them

can record the sound being played.


If it’s about playing a file and recording its audio to mp3, the
following will work:

ffmpeg -i your-file.avi your-file.mp3

Change your-file.mp3 to your-file.wav if you prefer wav output. 
Works with any input format ffmpeg can play.


Regards,
Victor

Re: pdftk

[Victor A. Stoichita]

Le 26 Aug 2019, Siard  a écrit :

AFAIK that should be:
$ pdftk file1.pdf file2.pdf cat output result.pdf


It also works without "cat". The OP seemed to be looking for the 
simplest possible form. 


Regards,
Victor

Re: pdftk

[Victor A. Stoichita]

Le 26 Aug 2019, steef  a écrit :


hi folks!

is there a simple commandline command to get pdftk so kind to 
merge
a couple of pdf-files? the explanation in the man 
and --help-files is
for me in somewhat cryptic english. kind regards, Now it 
complains

with 'input-errors'.

steef


What did you try?

To merge file1.pdf and file2.pdf into result.pdf:
$ pdftk file1.pdf file2.pdf output result.pdf

Regards,
Victor

Re: systemd not seeing my user units after reboot

[Victor A. Stoichita]

Le 23 Aug 2019, Sven Hartge  a écrit :


It was never not available in Sid. This normal for packages, 
they are

normally only removed from Testing.

Thanks for clarifying this. 

I guess that I was confused by the Debian wiki at 
https://wiki.debian.org/DebianUnstable The wiki says that Sid 
holds the "latest packages":
"Debian Unstable (also known by its codename "Sid") is not 
strictly a release, but rather a rolling development version of 
the Debian distribution containing the latest packages that have 
been introduced into Debian."


I wasn’t aware that it would also have *obsolete* packages that 
had been dropped from testing or stable. But of course, those 
obsolete packages might still be the "latest packages" available.


That page also describes Sid as a precursor for testing:
"The sequence of package propagation in the Debian development 
process is as follows:

   → experimental
   → unstable → testing → stable"

Same logic at https://www.debian.org/releases/sid/ : 
"This distribution will never get released; instead, packages from 
it will propagate into testing and then into a real release."


Obsolescence however seems to propagate the other way round, which 
is also kind of logic indeed. Thanks for pointing it to me!


Victor

Re: systemd not seeing my user units after reboot

[Victor A. Stoichita]

Le 23 Aug 2019, Sven Hartge  a écrit :


Victor A. Stoichita  wrote:

Could it be relevant that my home folder is encrypted with 
ecryptfs? How can I check whether it is now decrypted before or 
after systemd starts its user instance?


ecryptfs is not included nor supported in Debian 10.

https://www.debian.org/releases/buster/amd64/release-notes/ch-information.en.html#noteworthy-obsolete-packages


Thanks Sven!

That’s rather bad news for me. I should have read the news of 
course before upgrading. But I’ve been encrypting my home folder 
for so long that I didn’t even think that ecryptfs could be 
dropped out of stable without an alternative to it.


I just checked and ecryptfs-utils is available again in unstable 
(sid).
That package in unstable is binary identical with the one in 
oldstable (stretch). So I guess that it’s my understanding of 
"stability" which is wrong. 


Regards,
Victor

systemd not seeing my user units after reboot

[Victor A. Stoichita]

Hi,

I have some custom systemd units in ~/.config/systemd/user
In Debian 9 I could start my ~/.config/systemd/user/foo.service 
after reboot and login simply with 
$ systemctl --user start foo.service


Since I upgraded to Debian 10, I need to issue a prior
$ systemctl --user daemon-reload

If I don’t daemon-reload first, systemctl answers that "Unit 
foo.service not found". This carries the additional problem that 
when foo.service is enabled to start automatically after boot, it 
no longer starts automatically.


Could it be relevant that my home folder is encrypted with 
ecryptfs? How can I check whether it is now decrypted before or 
after systemd starts its user instance?
I’m interested in any other pointers about what could have changed 
in the upgrade and how I could to debug this.


Victor

Re: testing, mhwaveedit, anyone else having problem saving files?

[Victor A. Stoichita]

Le 05 May 2017, songbird  a écrit :

>   i haven't had to use this program in a while, but today
> was trying to fix an audio file and when i go to save it
> the program gives error message:
>
>   Failed to open '/home/me/smb/tmp1.flac'!
>
>   which is also annoying because it opens the file without
> any problem, but then it also erases it so there's nothing
> left.
>
>   luckily i do have backups so the file is recoverable.
>
>   it's a simple program that is useful, but perhaps nobody
> else ever uses it?
>
>   p.s. doesn't matter what i try to call the file or
> extension...
>
>
>   songbird

Hi songbird. Mhwaveedit works as usual here. I have 1.4.23 from testing
repo. Just tried it on a flac file. Open -> edit -> save -> reopen = no problem.

Mhwaveedit is very useful for me too as it is blazing fast for basic
audio file editing.

Did you try "save as…" and "save selection as…" as well ?

Victor

Re: Movie problem

[Victor A . Stoichita]

> The last time I looked at dvgrab, it had no camera controls, but I'll 
> have to admit that was several years ago. But can it edit? kino can.
>
> Odd, I can't find it in the tde menu's, but synaptic says it is 
> installed, but no docs. So I turned on the camera, and ran it from the 
> cli. I found the camera, and generated a file, but it never started the 
> camera in playback mode. Ack the manpage it needed a -i option. And I 
> see that Dan Dennedy wrote both, so its possible that kino uses dvgrab 
> to do the capture,  Interesting.  And you, Victor, should look at 
> kino. :)

I’m glad you sort of made it work! Interactive camera controls are
indeed behind the -i option in dvgrab. And you’re right, dvgrab can’t
edit, it’s just an acquisition tool.

I tried Kino some 10 years ago. I remember being a bit frustrated by
frequent crashes and editing oddities. Your recommandation made me
curious so I just checked Kino’s website. The last news dates back from
2013 and reads:

> "Kino is a dead project
> ( 05.08.2013 14:15 )
> Kino has not been actively maintained since 2009. We encourage you to
> try other Linux video editors such as Shotcut, Kdenlive, Flowblade,
> OpenShot, PiTiVi, LiVES, and LightWorks."

In the last years I’ve been using Openshot for simple editing. It proved
quite reliable. I also have an eye on PiTiVi but it still crashes too
often on me. I haven’t tried the others in the list. For more complex
stuff I managed to finish a couple of projects with Cinelerra, which
could be worth considering as an option too.

Cheers,
Victor

Re: Movie problem

[Victor A. Stoichita]

Hi Gene,

Camera is a Sony Digital Hi-8 Handycam, firewire interface. 
Raw video is bulky as its a digital format, full resolution of 
720x480.  so its close to 6 gigabytes a running minute when 
captured over the  firewire port. 

The only movie editor we have, that can also control this camera 
for  start/stop/capture etc, is kino. No other movie prosessing 
utility we  have has ever been in the same county as a firewire 
port


Did you try dvgrab? https://packages.debian.org/en/wheezy/dvgrab 
That’s what I use in commandline to capture Raw DV from my camera 
over firewire. I have an oldish Panasonic DV camera. Dvgrab knows 
perfectly how to start/stop it. I think dvgrab actually has some 
link to kino or the other way round.




Web submission site at aliexpress.com has no clue what to do 
with a a  raw-dv file and refuses to take it as an 
evidence submission. 

Kino, as in running on a fully uptodate wheezy, apparently can't 
find  ffmpeg to make the conversion when I attempt to export 
this 1 minutes  worth of raw-dv format video.  ffmpeg and all 
its friends are installed.  But in kino, the whole page of mpeg4 
options is ghosted out.


To convert from DV to mpeg4 you can use avidemux. It’s available 
on debian-multimedia.org, but it’s also easy to build it yourself 
if you don’t want to add a repo. Instructions here: 
http://www.avidemux.org/admWiki/doku.php?id=build:install_2.6 
There’s an option to build directly a deb file. That’s what I use. 
Note that currently only the Qt interface seems to work on Jessie 
(GTK one segfaults at startup at least for me). Avidemux comes 
with its own implementation of ffmpeg. IIRC you must build and 
install its plugins too if you want mpeg4 conversion.


In avidemux, the settings I use to get an acceptable mp4 for the 
web are: MPEG4-AVC for the video, AAC for audio, and of course MP4 
as a container.


I hope it helps. Good luck!

Victor

Re: Truncating MPGs or MP4s

[Victor A . Stoichita]

project-x should also be able to do that.


Useful info, thanks! 

Project-x may be a bit more limited than ffmpeg and avidemux 
though as

it doesn't support H.264 (disclaimer on
http://project-x.sourceforge.net/).

Re: Truncating MPGs or MP4s

[Victor A . Stoichita]

I usually use avidemux for that, telling it to copy the audio 
and video 
rather then reencode them. Then I do the transcoding 
with handbrake.


+1 for Avidemux as a GUI tool. To my knowledge it is the only gui 
tool
in linux which allows simple truncation of files 
without reencoding.
Last time I checked, Openshot, Pitivi and Kino couldn’t just 
truncate

(copy) the streams, they always reencoded them. Apart from loss of
quality, this also means loss of time.

I also use the ffmpeg solution mentioned earlier. It’s simple and
effective if you don’t need frame accurate precision in 
your timings.
Technically truncation can’t actually start or stop on just any 
frame in

the video. Start and stop must be on a keyframe (one of the frames
encoded in full and not deduced from others, more on this here:
http://www.avidemux.org/admWiki/doku.php?id=using:cutting).

I'm not sure how ffmpeg deals with the situation where the 
timecodes you

specify don’t match actual keyframes. I suppose they shift the
start/stop time a bit earlier or later. It’s usually not a big 
deal but
sometimes it matters. If you want full control over this, 
avidemux’s gui

can help you set the trim markers to keyframes.

In case you don’t want to enable an extra repo just for avidemux, 
it’s
fairly easy to compile it yourself. I followed the instructions 
here:
http://www.avidemux.org/admWiki/doku.php?id=build:install_2.6 The 
gtk
gui crashes on my debian testing with xfce, but the qt one (which 
is the

default) works just fine.


Regards,
Victor