Friday, January 28, 2022

Video - vlc crash, reduce video size, resolutions, davinci on linux

Vlc crashes when taking a screenshot

I tried to take a screenshot from a .mkv video and it crashes every time though it works fine with normal mp4.

To fix it disable hardware acceleration in codecs.

Go to Preferences - Input/Codecs - Hardware-accelerated decoding - 

Change from Automatic to Disabled.

Try again. It worked for me.

How To Reduce a Video File Size

Download Handbrake : https://handbrake.fr/downloads.php

Install handbrake then follow the image instructions :

1. Select Source and put you video in or just drag the video over handbrake window.
2. Select Destination and type and name for the video.
3. Select the Video tab and drag Quality to the left up to 25 or even lower dont go lower then 30 as it gets bad, but you can test and see what you like.
4. Pres Start.

Resolutions compatible with full hd or 1920 x 1080

HD     720p   -- 1.77:1 (16:9)  /  1280x720
FHD 1080p -- 1.77:1 (16:9)  /  1920x1080
QHD                                        2560x1440
UHD 4k       -- 1.77:1 (16:9)  /  3840x2160

At under 100 ppi image gets pixalated from close up 20-30cm
For a PPI ~100
4k 3840x MAX 42 inch
QHD -  MAX 27 inch
FHD MAX 22 inch 

Run Davinci on Linux

Once you install DaVinci you  get a message that no suported video cards are detected and something about no media storage.
You need to install video and opencl drivers.


Wednesday, January 12, 2022

Install scanner in linux - Brother DCP-7030

Scanner in LINUX - SANE - Scanner Access Now Easy


sudo sane-find-scanner  *** list connected scanners
lsubs *** view usb connected devices ( sudo apt install usbutils )

scanimage -L  *** check if sane detects your scanner
SANE_DEBUG_DLL=3 scanimage -L
load: dlopen() failed (libusb-0.1.so.4: cannot open shared object file: No such file or directory)

To fix it:
apt search --names-only libusb-0.1
rezult: libusb-0.1-4/stable 2:0.1.12-32 amd64 
sudo apt install libusb-0.1-4 

Open the file -> /etc/sane.d/dll.conf 
and add one line with 
brother3
!!! note when you run scanimage -L it will check every record, so just delete all records and leave your printer name

Create a new file with your printer name and add it.
brother.conf
firmware /usr/lib64/sane/libsane-brother3.so.1.0.7
usb 0x04f9 0x01ea

!!! you get vendor id from lsusb or sane-find-scanner

You might just use the install package to install the rules file automaticly instead.
/etc/udev/rules.d/60-myprinter.rules
# Brother scanner
ATTRS{idVendor}=="04f9", MODE="0666", GROUP="scanner", ENV{libsane_matched}="yes"
!!! change idVendor - with your printer vendor id

Brother DCP-7030
udev rules -> brother-udev-rule-type1-1.0.2-0.all.deb
driver -> brscan3-0.2.13-1.amd64.deb

reboot
Things I did that i don't think are necesary:
sudo usermod -a -G myuser scanner
Copy the driver files under /usr/lib64/ to /usr/lib/.

For printing
Install cups, and brlaser (driver)
then go to localhost:631 - adminstration - add printer - done