Domoticz - Handle your exhaust speed according to humidity level

dropcap domoticz

Nowadays, a Mechanical Controlled Ventilation (VMC in French) is a de-facto equipment in a bathroom.

Most of these Controlled Ventilation can run in two different speeds : low speed and high speed. VMC runs low speed any time and can be switched to high speed with a manual switch.

Thanks to home automation, it is now possible to automatically manage your Controlled Ventilation speed according to humidity level in the room.

This article explains how to automatically manage a Controlled Ventilation speed according to humidity level in a bathroom with the help of :

  • a wireless humidity sensor
  • a wireless switch
  • a wireless gateway
  • Domoticz, a very nice Open Source Home Automation Software

This setup has been tested on a Debian 8 Jessie server with a RfxTrx433 gateway, an Oregon Scientific THGR 122 Temperature/Humidity sensor and a DiO 54755 switch. All RF devices are working on 433 MHz frequency. But any other similar setup and devices should work as long as they are compatible with Domotiz.

Read more: Domoticz - Handle your exhaust speed according to humidity level

Debian - Send your Server Notifications thru Telegram

dropcap debian telegram

As a system administrator, you must be receiving your important server notifications by emails. Email has been used since decades, but it is slowly replaced in everydays life by social networks. With social network clients, messages are usually displayed as thread and get instant notification on your smartphone.

So, why not receiving your main server notifications on one of your favorite social network client ?

Telegram is becoming a very popular social network as it is free and multi-platforms. It has also a unique feature : it's allowing the use of bots. Bots are very interesting as they can be seen as an application account associated to a real person's account. They are able to send or receive messages to/from either an individual account or a group.

So, instead of sending a mail, it could be very interesting for your Debian/Ubuntu server to be able to send you Telegram notification. You can for example create an administrator group and send all your server notifications to this group. Any administrator belonging to this Telegram group will get instant notification from the server.

This article explains how to setup a server environment to very easily send Telegram notifications from any of your server script or service. It also provides a script that allows you to send Telegram messages including text, photos, documents, logs, …

It has been tested on a Debian 8.5 server but it should work on any modern Linux distribution.

Read more: Debian - Send your Server Notifications thru Telegram

Ubuntu 16.04 - Rotate & Stabilize your video with MLT and Vid.stab

dropcap-ubuntu-stabilize

Nowadays, street video shooting is becoming a reality.  With any modern smartphone, point-and-shoot camera or even a GoPro camera, you can shoot any video anywhere.

These devices are affordable, light-weight, very compact and easy to use. Whatever happens around you, you are able to record it on the spot. But, on the other end, as these devices are compact and light, they are not very steady. Your recordings tend to be shaky !

Another problem you can encounter when shooting from a smartphone is that your video may be recorded upside-down or even rotated by 90°.

Till date, I did not find any very simple solution under Linux to simply stabilize (unshake) and/or rotate my day-to-day videos.

Hopefully, thanks to MLT framework, it is possible to use a command line tool melt and some specific plugins (vid.stab to stabilize and affine to rotate) to do the job.

This article explains how to easily post-process any group of video files straight from Nautilus file manager to rotate and stabilize them. The tool handles following actions :

  • read important metadata
  • rotate video if needed
  • stabilize video if needed
  • transcode it to h264 & aac

It has been designed and tested nder Ubuntu and Ubuntu Gnome Xenial 16.04 LTS. It should be applicable to many up-to-date Linux distro.

Read more: Ubuntu 16.04 - Rotate & Stabilize your video with MLT and Vid.stab

Nautilus - Handle EXIF tags and geolocalisation data

dropcap image geotag

With smartphones or modern digital camera, all digital photos files are now generated with plenty of useful tags.

These tags can be of different type  : EXIF, IPTC or XMP. They can also include some GPS localisation data.

Actually, on a Ubuntu 16.04 workstation, there is no simple way to visualize all these tags  straight from Nautilus file manager when you manage your digital image folders.

This article explains how to extend Nautilus with some simple python extension to :

  • add some columns providing specific image informations (camera model, city, country, GPS data, ...)
  • provide a picture property tab with all picture tags (EXIF, IPTC, XMP, ...)
  • provide a picture property tab with GPS map and address

This procedure has been tested under Ubuntu Gnome 16.04 LTS and Ubuntu 16.04 LTS running Gnome Classic, but it should be applicable to many other modern Gnome Shell based distributions.

Read more: Nautilus - Handle EXIF tags and geolocalisation data

Ubuntu 16.04 - Correct GoPro USB access bug

dropcap ubuntu gopro

Under Ubuntu 16.04 Xenial, a nasty bug stops you to mount latest GoPro action cams. 

I discovered this problem while connecting a GoPro Hero Session 4 to my laptop via the USB cable. In Nautilus, the device was showing, but it was showing some weird directories :

  • DCIM_00000001_00000001
  • DCIM_00000001

Both directories were empty.

After some internet search, I realised that this problem seems to occur with few recent models of GoPro action cams.

This short article explains how to solve this problem and to properly mount latest GoPro action cams via USB under Ubuntu 16.04 Xerial. 

It has been tested with a GoPro Hero Session 4 connected on a Ubuntu Gnome 16.04.1 LTS Amd64 laptop.

Read more: Ubuntu 16.04 - Correct GoPro USB access bug

Gnome Shell - Management of Extensions from console

dropcap-gnome-shell

Under Debian or Ubuntu, Gnome Shell default installation comes with very few extensions.

Hopefully, huge number of extensions are available from Gnome Shell Extensions store.

This store is a fantastic improvment, but you need to install all extensions one by one from the web site.
Till date, there is no official way to install them in console mode.

This is quite annoying if you are a sysadmin and you are handling quite a big amount of workstations, as most of your installation process must be scripted.

This article explains how to install & remove any Gnome Shell extension from https://extensions.gnome.org/ via a console command.

It has been tested under Ubuntu Trusty 14.04 / Gnome Shell 3.8 and Ubuntu Xenial 16.04 / Gnome Shell 3.18.
But it should work on any Ubuntu or Debian flavour and with latest Gnome Shell versions.

Read more: Gnome Shell - Management of Extensions from console

Gnome Shell - Add New Document to Nautilus contextual menu

dropcap nautilus

With Gnome 3, Nautilus doesn't provide any more an empty file creation menu.

As amazing as it can be, this very simple and very productive feature has been remove with Gnome 3. You still can create an empty folder, but not an empty file !

As this very simple feature is a must have, this article explains how to get it back, but boosted with steroids. It explains how to setup Nautilus to handle creation of different empty document types, based on some document models you have written and provided.

You'll then be able to create any type of new documents customised to your specific need (writer document with your letter head, bash script with your default title block, …).

ubuntu nautilus newfile menu

It has been tested on Ubuntu 14.04 LTS and Ubuntu 16.04 LTS, but should be installable on any Linux distribution.

Read more: Gnome Shell - Add New Document to Nautilus contextual menu

Ubuntu 16.04 - Installation on HP Stream 13

dropcap hpstream13

HP Stream 13 is very light, compact and affordable laptop. Its overall design is also quite good.

Technically speaking, it holds an Intel Celeron N2840 Dual-core CPU, 2 Gb of RAM, a 32 Gb eMMC and a 13' display with Intel HD Graphics.

So, it is a perfect laptop to run Ubuntu instead of the preinstalled Windows.

This short article explains how to install Ubuntu 16.04 LTS 64bits on a HP Stream 13 and how to tweak it to have a very smooth Ubuntu experience on this laptop.

Read more: Ubuntu 16.04 - Installation on HP Stream 13

Debian - Downscale Webcam in realtime for Internet Access

dropcap webcam internet

As part of a complete domotic project, I had to setup some security cams. These cams are connected thru ethernet or wifi to a domoticz server. They are HD cams, able to serve 1280×720 high quality JPG pictures.

As they are used for motion detection purpose, it's important to keep the picture quality as high as possible for investigation purpose. But on the other side, as they should be available from anywhere on a supervision console, they should also be available thru internet with a resolution compatible with internet limited bandwidth.

Solution to this problem is to allow :

  • full resolution picture while served on the LAN
  • real time picture transcoding if served thru Internet

This article explains how to setup an Apache web server to handle realtime transcoding of some declared security cams images so that their dimension and quality level are adjusted to internet transmission. As a result, your security system will get high quality images on your LAN and optimized size and quality if served thru Internet.

Read more: Debian - Downscale Webcam in realtime for Internet Access

Ubuntu - Installation on Acer Aspire One Cloudbook 431

dropcap ao1 431 ubuntu

This year, Santa Claus has brought an Acer Aspire One Cloudbook 431 in the family.
This laptop is a nice, light, very compact and affordable laptop.

With Intel Celeron N3050 Dual-core, 2 Gb of RAM, 64 Gb eMMC and a 14' display, it is a perfect laptop to run Ubuntu instead of the pre-installed Windows 10. Thanks to the hardware provided, latest Ubuntu 15.10 64bits works Out Of the Box (touchpad, sound, wifi, webcam, …).

But when you try to install Ubuntu, you'll notice that installation process with an Ubuntu Live USB key is giving trouble :

  • In Legacy mode, it just hangs at some stage
  • In UEFI mode, it installs just fine, but the laptop indicates No media found during boot process

This article explains how to replace Windows 10 with Ubuntu 15.10 64bits on an Acer Aspire One Cloudbook 431 in UEFI mode.

Read more: Ubuntu - Installation on Acer Aspire One Cloudbook 431

Ubuntu - Generate PDF file from any set of documents

dropcap pdf

Nowadays, PDF has become the de facto exchange file format for most documents. Whenever you need to send a document to someone using a smartphone, a Linux PC, a Windows PC or a Mac, by sending a PDF file, you'll be confident that your recipient will be able to open and read it.

Till date, under Linux, I haven't found a simple tool able to generate a PDF file in one click from a selection of miscellaneous documents like :

  • a serie of scanned pages
  • some office documents (doc, docx, odf, xls, …)
  • some text files
  • some photos (.jpg, .png, ...)

ubuntu pdf generate

This article explains how to setup a desktop environment under Linux which will allow you to convert any set of documents to a single multi-pages PDF document. All documents will be merged in alphabetical order according to their filename. Conversion will be accessible straight from the comfort of your Linux file manager (Nautilus, …).

Read more: Ubuntu - Generate PDF file from any set of documents

Page 1 of 9