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The following is not exclusive to Ubuntu. It probably works on any Linux.

As many of you know, I am an ENT surgeon by profession, and also a tech enthusiast. As part of my trade, I need to do endoscopy of the nose and throat, and also record and give reports to patients. For this, I use a cheap AV to USB recording device, called EasyCap. For Windows, it comes with a recording software, called Honestech. However. for Linux. one can simply use vlc for recording.

Install vlc:

sudo apt install vlc

For recording, the steps include:

Install vlc.
Open vlc
Open Network Stream:
Video device name: /dev/video2

In View

You may need to change and try the various available video devices. One of them will be your webcam, and the other, the AV to USB device.

If the color saturation bothers you, install v4l2ucp.

It is not normally available for Ubuntu 20+, but you can install it like below:

Download the deb from here

First install qt4:

sudo add-apt-repository ppa:rock-core/qt4
sudo apt-get update
sudo apt-get install libqtcore4
sudo dpkg -i ~/Downloads/v4l2ucp_2.0.2-4build1_amd64.deb
sudo apt-get install -f

You can experiment with color settings by loading v4l2ucp

A snackbar is a convenient widget for displaying short messages about completed events.

To create a Snackbar, use the code:

        content: Text('$response'),
        backgroundColor: msgColor,

Usually it’s a permission issue. You need webserver ownership (www/www-root or something else depending on your server) for all files:

chown -R www.www public_html

You also need to change permissions of your files and add write permissions for user and group:

chmod -R ug+w public_html/

You may also need to add the following line to wp-config.php:

define( 'FS_METHOD', 'direct' );

The following error is noted while running adb:

$ adb shell
adb server version (41) doesn’t match this client (39); killing…
ADB server didn’t ACK
Full server startup log: /tmp/adb.1000.log
Server had pid: 19748
— adb starting (pid 19748) —
adb I 04-06 12:07:01 19748 19748 main.cpp:57] Android Debug Bridge version 1.0.39
adb I 04-06 12:07:01 19748 19748 main.cpp:57] Version 1:8.1.0+r23-5~18.04
adb I 04-06 12:07:01 19748 19748 main.cpp:57] Installed as /usr/lib/android-sdk/platform-tools/adb
adb I 04-06 12:07:01 19748 19748 main.cpp:57]
adb I 04-06 12:07:01 19748 19748 adb_auth_host.cpp:416] adb_auth_init…
adb I 04-06 12:07:01 19748 19748 adb_auth_host.cpp:174] read_key_file ‘/home/joel/.android/adbkey’…
adb I 04-06 12:07:01 19748 19748 adb_auth_host.cpp:391] adb_auth_inotify_init…
adb I 04-06 12:07:01 19748 19748 adb_auth_host.cpp:467] Calling send_auth_response
adb I 04-06 12:07:01 19748 19748 adb_auth_host.cpp:467] Calling send_auth_response
adb server killed by remote request

failed to start daemon error: cannot connect to daemon

The error is because of adb version. Use the adb that comes with Android SDK.

$ adb –version
Android Debug Bridge version 1.0.39
Version 1:8.1.0+r23-5~18.04
Installed as /usr/lib/android-sdk/platform-tools/adb

To fix:

/home/joel/Android/Sdk/platform-tools/adb --version
 Android Debug Bridge version 1.0.41
 Version 29.0.6-6198805
 Installed as /home/joel/Android/Sdk/platform-tools/adb
 [email protected]:/home/joel# cp /home/joel/Android/Sdk/platform-tools/adb /usr/bin/[email protected]:/home/joel# adb
 Android Debug Bridge version 1.0.41
 Version 29.0.6-6198805
 Installed as /usr/bin/adb

#adb devices
 List of devices attached
 20da0e00    device
 emulator-5554    device

#adb -s 20da0e00 shell

I had bought a 23.5″ Samsung curved monitor three months ago. It had been subjected to the utmost care, and the monitor remained on the computer table and was not moved from its location at any point in time. In January, black areas were noted on the screen, which made the monitor unusable. I must confess that having never used curved LCD monitors before, I had been wary of buying one from Samsung India. The black patches extended over the entire screen rendering the monitor unusable.

On 06/02/20, a service request was placed on Samsung website. Two days later a technician visited and “inspected” the product. His detailed inspection involved peering curiously at the monitor, calling his head honchos, and taking detailed photographs. He did not have a screwdriver or other tools. He did not touch my monitor at any point of time. He curtly informed me that the product was subject to physical damage and could not be repaired under warranty, and that if I needed to repair it, I should pay the full amount.

On 14-02-2020, a legal notice was sent to Samsung India giving them a notice period of 10 days before filing a Consumer Case, and giving them opportunity to repair my product free of cost as it was in warranty. However even though I received a few calls from Samsung, it was only to argue that my product was not covered under manufacturer warranty as it had physical damage. They were unwilling to accept my contention that it could not have physical damage as it didnt have any kind of scratch, graze or crack on it.

Online forums are filled with similiar reports of thermal damage happening to Samsung Monitors without any kind of physical damage. However Samsung is not only willing to accept that their product has a defect, but also consciously violates the Consumer rules of India, which state that a product in warranty has to be serviced free of cost.

I have filed a Consumer Case in the National Grievance Redressal forum, and am waiting for being summoned to provide facts.

Have you ever faced an issue of tinny sound on certain laptop models, and wished that you could increase sound levels a little bit further than provided by the maximum levels in system? To increase volume by 10%:

pactl -- set-sink-volume 0 +10%

To set volume to 110%:

pactl -- set-sink-volume 0 110%

By using these commands, you can often sound volume to a level that is not provided by the default system widgets.

Nemo allows the user to add new entries to the context menu. The file /usr/share/nemo/actions/sample.nemo_action contains an example of a Nemo action. Directories to place custom action files:

/usr/share/nemo/actions/ for system-wide actions
~/.local/share/nemo/actions/ for user actions
Action files must have the .nemo_action file extension.