Update UUID of existing exFAT partition
tune.exfat -I 0x<UUID> <partition>
Capture video using ffmpeg with an Intensity Pro and compress using VA-API
Hardware accelerated video capturing using VA-API and a Blackmagic Intensity Pro: H.264 video, FLAC audio. Needs a snapshot ffmpeg build with latest Blackmagic SDK & libva: --enable-decklink --enable-vaapi.
ffmpeg -v verbose -vaapi_device /dev/dri/renderD128 -hwaccel vaapi -format_code ntsc -f decklink -i 'Intensity Pro' -c:a flac -compression_level:a 7 -vf 'format=nv12,hwupload' -c:v h264_vaapi -global_quality 10 -y output.mkv
Color correction of VHS recordings
Calculated using Moth3r’s spreadsheet by recording a test card to a new blank VHS tape.
Panasonic DMR-EZ49V (PAL machine in NTSC mode):
ColorYUV(gain_y=11.11, off_y=3.34, gamma_y=-18.49, off_u=0.92, cont_u=27.20, off_v=0.83, cont_v=41.55)
JVC DR-MV5S (NTSC machine):
ColorYUV(gain_y=23.22, off_y=1.44, gamma_y=-14.03, off_u=2.21, cont_u=40.83, off_v=2.70, cont_v=22.24)
Remaining mean error <=3.
Backup file invalid: fix broken Threema backup
Extract backup and ignore Unexpected end of archive error…
7z x threema-backup_*.zip
… and recompress with password.
cd threema-backup_*
7z a -p -mem=AES256 -tzip ../threema-backup_<original_filename>.zip *
Check compression method and encryption (Method = AES-256 Deflate):
7z l -slt threema-backup_<original_filename>.zip
Attempt to perform an operation not allowed by the security policy `PDF’
Change
<policy domain="coder" rights="none" pattern="PDF" />
to
<policy domain="coder" rights="read | write" pattern="PDF" />
in /etc/ImageMagick-?/policy.xml.
Remove invalid characters from filename
detox -r -v -n path/
Nextcloud: reset user password
sudo -u <webuser> php occ user:resetpassword <nextclouduser>
Auto align images and apply median blending
Auto align images using Hugin (source images might need the exact same resolution):
align_image_stack -m -a output_prefix input1.png input2.png
Median blend images using Imagemagick:
convert output_prefix*.tif -evaluate-sequence median output.png
Force Thunderbird to check all folders for new mail
Set mail.server.default.check_all_folders_for_new to true using the config editor (advanced settings).
Using substrings in bash
${var:offset:length}