Freitag, 4. Dezember 2015

How to capture video from digital dv camcorder via usb in Linux

Google wasn't really helpful on this one.
Most posts were from before 2012, when there was hardly any support for video capture via usb, apparently. But actually "reading"(TM) the manpage of dvgrab revealed that the support for usb was implemented later.

So I tried it on my Panasonic NV-GS180EG and it worked:

Connect to USB
The usb port at the camcorder is kind of hidden. But it is there.

Start video capture
dvgrab -V -input /dev/video1  
For me, the camera was in /dev/video1, which was only available after connecting the camcorder to the usb port.

dvgrab is now waiting for a video signal
"Waiting for DV..."

 Start video playback on your camcorder (physically)
The camcorder will now send the video (and audio) signal via usb, where it gets recognized by dvgreb ...





"Capture Started"


... and saved to disc
""dvgrab-001.dv":   999.89 MiB  7281 frames timecode 00:04:51.16 date 2000.01.01 00:00:00"

As can be seen, these files are huge, so you better have some free disc space to spend.

You can stop the capturing with
Ctrl + C
but it will also stop automatically once the video signal stops.


I converted the to avi format with VLC which reduced the size about 20 fold.

Donnerstag, 26. November 2015

restart wifi

Since I don't want to reboot my laptop each time the wifi won't connect...

restart the network manager (ubuntu)

sudo service network-manager restart

Works like a charm.

Easy to do stuff to enhance your (online) security

You know, Edward Snowden and stuff ...

All of this can be installed with basic knowledge within minutes on a unix system. I use Ubuntu.

encrypt your data with ecryptfs-utils

Create a folder within your homes, that is ecryptet when you turn your computer off. That way, when you lose it your data is (reasonably) save.

install:
sudo apt-get install ecryptfs-utils

create a folder "Private" in your homes

ecryptfs-setup-private
You will be asked to enter your Login-Password and a Passphrase (don't).
Don't enter a passphrase, a good one will be created automatically.

now go to ~/.ecryptfs (in your homes)
cd ~/.ecryptfs

and enter

ecryptfs-unwrap-passphrase
to extract your passphrase.

Write down your passphrase and store it at a save place, otherwise
your data could be lost forever.

Reboot.

Now there is a folder "Private" in your homes where you can store your secret data.

Your data is only as save as your login password is good!

Install a tor browser

and use it whenever you want to surf with at least some anonymity.

https://www.torproject.org/

cd into the tor folder
 cd tor-browser_en-US/

and start tor

./start-tor-browser.desktop

Get https-everywhere for your browser

https://www.eff.org/https-everywhere

It's as easy as it gets. The tor browser already has it.


To be continued...



How to copy and paste in terminal like applications

How to copy and paste in terminal like applications

How could I consider myself a computer scientist without knowing this?

CTRL + SHIFT + c -> copy


CTRL + SHIFT + v -> insert

Basically as known, only add SHIFT

How to turn off the internal camera of your laptop (Linux)

How to turn off the internal camera of your laptop (Linux):


Cameras are controlled by the uvcvideo kernel module.

You can disable the camera until reboot by opening a terminal and typing
sudo modprobe -r uvcvideo
You will be asked for your password, and after typing it, if there are no errors shown in the terminal, your webcam should be disabled.
If you got the error message: modprobe: FATAL: Module uvcvideo is in use. after trying to remove the uvcvideo module, you can try to force its removal with the following:  
sudo rmmod -f uvcvideo


To enable your webcam again, type
sudo modprobe uvcvideo
into terminal.


If you want the camera to be disabled when you reboot, then press
ALT+F2
and paste this command:
gksu gedit /etc/modprobe.d/blacklist.conf
You will be asked for your password. After giving it, a text file should open. Paste at the end of the text file on a new line:
blacklist uvcvideo
Then save the file and exit. Next time you start Ubuntu, the webcam should be disabled.

credit:
 https://askubuntu.com/questions/166809/how-can-i-disable-my-webcam