Convert Your media files

c3phas — Thu, 27 Jun 2019 09:48:42 +0000

ffmpeg

So you have the video but can’t play it ‘cos of the format ?
You want an mp3 but have got the mp4 or other video format ?
You want the Video without the sound
You have an image that should be the background of your mp3 file

ffmpeg according to the man page is a fast video and audio converter
ffmpeg library is cross platform thus can be used in any operating system ,
ffmpeg can be used for a torn of things but we only look at the basic here, This library is used in the background by famous video editors .

Install ffmpeg on debian based system

apt-get install ffmpeg

Lets begin by converting a video(mp4 to an mp3)

NOTE: ffmpeg is a command line program.

ffmpeg -i input.mp4 -vn output.mp3

-i is used to specify the input file , the file can be an mp4 ,webm or other video formats
-vn – this option is used to disable the video recording. It grabs the video and gets rid of it
output.mp3 is the output file name

The above command will convert the input.mp4 to output.mp3
Other related options include
-sn – disable the subtitle
-an -disable the audio recording

examples
ffmpeg -i input.mp4 -sn output.mp4
if the input had subtitles enabled the output will be free of subtitle

ffmpeg -i input.mp4 -an output.mp4

will result into a video with no sound

Convert a video from one format to another( say from flv to avi)

ffmpeg -i input.flv -q:a 0 -q:v 0 -f avi output.avi

-i specify the input file
-q used to set the quality of the audio and video file , a is for audio and v is for video
-q:a 0 means the output audio quality should be the same as the input audio quality(mainly called streams
-f -is used to specify the target format in this case we want an avi output

note The only thing you need to change are the input format and output format

Add an image to the mp3 file
so you have an mp3 but want to use your pic instead of staring at the bare screen
ffmpeg -loop 1 -y -i input.jpg -i input.mp3 -acodec flac -vcodec libX264 -shortest -preset fast vf scale=1280:2 output.mkv

well well now we get a bit advanced here
we have some more options lets look at some of them

codecs – This simply refers to the media bitstream( How the media will be encoded and decoded)
acodec is used to set the audio bit stream in our case we use flac
vcodec sets the video codec
-y if a file with same name as the output name is present it will be deleted ie overwrite the output without asking ( -n is the opposite , says do not overwrite )
-loop 1 - will loop our image until the mp3 finishes
-shortest – Finish encoding when the shortest input stream ends
-preset fast – how fast will the compression process take. Can be set to fast,slow ,very slow etc
when the value is set to fast , The quality of the output might be low but the process will end quickly. Its a trade off speed vs quality
The next vf is used to set the video format in this case we set the output video size using the scale option , The output video will be 1280 wide

NOTE: we have specified two input files , an image and an audio file
To suppress the output add the option ( -hide_banner)

if you wish to just preview how your output will be , use ffplay to play the file without saving it
ffplay -i input

Ffmpeg can be used for far more advanced things which is impossible to cover.. Check the ffmpeg documentation
To get a more clear bash script visit my github https://github.com/peter-macharia/media-converter

Forgot my Root password

c3phas — Thu, 27 Jun 2019 08:08:47 +0000

MEEEEEEEEEN WHAT WAS THE ROOT PASSWORD

Today we are going to play around with our Linux box

NOTE:This article can be used for malicious activity
I hereby take no responsibility for how you will utilize
the following

Forgot your Linux root password? well lets get around it

Run Levels in Linux
A run level in Linux is what determines what programs will run
or will be executed at system startup
This is what determines whether your system loads a GUI or the
CLI mode when booting

There are 7 run levels staring from 0-6
Each runlevel has some services started or stopped and this is normally what determines the default behavior of the machine
I will not get into much details concerning this levels, if you want a more detailed explanation leave a comment.
The runlevels are
runlevel 0 - system halt
runlevel 1 - single mode
runlevel 2 - multiple user mode without network file system
runlevel 3 - multiple user mode under CLI mode
runlevel 4 - This is left blank thus it can defined by the user
runlevel 5 - multiple user mode under graphical user interface(default on most desktops
runlevel 6 - reboot

The two used modes by default are the runlevel 3 and the runlevel 5
if you want to find out which runlevel you are on ,on the terminal type
$runlevel
The scripts driving this levels are located in the /etc directory

THE MEAT OF THIS ARTICLE
our primary focus is the runlevel 1(single user mode)
This can be compared to what the folks at windows call safe mode
in this mode networking services will not be started but it allows one to make changes to the system

NOTE:This will only work if the systems' grub menu is not password protected

lets do this folks:
step 1: Reboot your machine and on the grub menu hit 'e' to enter the edit mode.
step 2: Find the line that starts with Linux and scroll to the end of that line
step 3: Delete the characters all the way to 'ro'
-The ro stands for read only ,change this to 'rw' to allow writing
-After replacing ro with rw hit space and add init=/bin/bash
your line looks like this
rw init=/bin/bash
step 4: Hit Ctrl-x or f10 to boot with current settings

The boot now gives you a shell with root privileges and you can go ahead and change the root password the usual way.

$passwd root

After confirming the password, reboot and there we have it , a new root password.

DEV Community: c3phas

Convert Your media files

ffmpeg

Forgot my Root password