Setting up ROS on Linux Mint 20 (Ulyana)

  • Posted on: 20 September 2021
  • By: dexter

ROS is an open-source, meta-operating system for your robot. It provides the services you would expect from an operating system, including hardware abstraction, low-level device control, implementation of commonly-used functionality, message-passing between processes, and package management. It also provides tools and libraries for obtaining, building, writing, and running code across multiple computers

Increase video volume using ffmpeg

  • Posted on: 17 September 2021
  • By: dexter

Sometimes recorded video, screecasts etc have a low volume, if you want to increase the volume without getting into too much complication, you can simply use ffmpeg for the same.

The command:

ffmpeg -i foo.mp4  -filter:a  "volume=5.0"  foo-high-volumet.mp4

Here:

ffmpeg is the command

-i assigns input file i.e. foo.mp4

-filter: for audio filter

jQuery - How to address a cell in HTML Table

  • Posted on: 24 August 2021
  • By: dexter

Senario:  To be able to access a particular cell <td></td> on one of the rows in HTML table. Using jQuery we can easily access a particular row and then target a cell of a HTML table easily by using the eq() traversal filter method and the :nt-child() pseudo-class  methods available.

Shell Builtin command

  • Posted on: 27 July 2021
  • By: dexter

Shell like bash or sh are application which provide you a way to run other application/commands via the command line interface.

Most of the command and applications which you run (like vi, nano, ls, fsck etc) are separate applications, when you type in any of these commands the shell looks them up and runs them.

you can use a command called ‘which’ to find out where a particular command file is located. (e.g. which ls will give you where ls command is)