Quick Tips

Cinemagoer Extract

imdbpy search movie "12 Monkeys"
python ../../util/test.py 0114746 > 12_Monkeys.json

Image Stabilization

FFMPEG

ffmpeg -i input.mp4 -vf vidstabdetect=shakiness=10:accuracy=15 -f null -
ffmpeg -i input.mp4 -vf vidstabtransform=smoothing=30:zoom=0 output.mp4

First command generates the convolution file, second command applies it.

Remove Subitles

ffmpeg -i series_launch_english.mp4 -c copy -sn series_launch_english_nosubs.mp4

See Also: https://start.duckduckgo.com/?q=Advanced+SubStation+Alpha&ia=web

DVD Handling

Make ISO Image

$ time dd if=/dev/sr0 of=/media/bob/backup/media/tmp/How_to_Train_Your_Dragon.iso bs=4M status=progress

Copy to Disk

makemkvcon mkv --minlength=3600 disc:0 all mkv_out_01/
makemkvcon mkv --minlength=3600 iso:How_to_Train_Your_Dragon.iso all dragon_out/

Downscale MKV With Subtitles and Audio

export FILE=mkv_out_01/foo.mkv
(ffmpeg -i "$FILE" -vf cropdetect -f null - 2>&1 & echo $! > /tmp/cropdetect.id) | grep crop | head -30000 | awk '{print $14}' | sort | uniq -c | sort -n && pkill -P $(cat /tmp/cropdetect.id)
export CROP=crop=720:200:90:60
ffmpeg -i "$FILE" -map 0 -vf "$CROP" -c:v libx264 -crf 23 -preset fast -b:a 196k -c:s copy Magnificent_Seven-The.mkv
ffmpeg -i "$FILE" -map 0 -vf "yadif=1:-1:0,$CROP" -c:v libx264 -crf 23 -preset fast -b:a 196k -c:s copy Magnificent_Seven-The.mkv

To use AAC if Vorbis is barfing:

ffmpeg -i "$FILE" -map 0 -vf "$CROP" -c:v libx264 -c:a aac -crf 23 -preset fast -b:a 196k -c:s copy Magnificent_Seven-The.mkv

ffmpeg -i "$FILE" -map 0 -vf "scale=-1:720" -c:v libx264  -crf 23 -preset fast -b:a 196k -c:s copy "../$FILE"

(ffmpeg -i "$FILE" -vf cropdetect -f null - 2>&1 & echo $! > /tmp/cropdetect.id) | grep crop | head -10000 | tail -5000 | shuf | head -10 && pkill -P $(cat /tmp/cropdetect.id)
ffmpeg -i "$FILE" -vf cropdetect -f null - 2>&1 | grep crop | head -10000 | tail -5000 | shuf | head -10

crf 23 is mid-field

crf 28 is aggressive compression

ffmpeg -i "$FILE" -map 0 -vf "scale=-1:720" -c:v libx264  -crf 23 -preset fast -b:a 128k -c:s copy Firefly-s01e01-Serenity.mkv

ffmpeg -i mkv_out_01/Zombieland_t00.mkv  -map 0 -vf scale=-1:720 -c:v libx264 -crf 23 -preset fast -b:a 128k -c:s copy Zombieland.mkv

720:368:0:54

ffmpeg -i input.mp4 -vf "crop=720:368:0:54" -c:v libx264 -crf 23 -preset fast output.mp4

ffmpeg -i mkv_out_01/Zombieland-J1_t00.mkv -map 0 -vf "crop=720:352:0:66" -c:v libx264 -crf 23 -preset fast -b:a 128k -c:s copy Zombieland.mkv

Fix aspect ratio without changing pixels:

ffmpeg -i input.mp4 -c copy -aspect 16:9 output.mp4

All Episodes

export CROP=crop=720:480:0:0
export VPATH=monk-s06d01 ; ls $VPATH | perl -e '$a=0;while(<>){$a++;$b="0".$a;if($a>9){$b="".$a;}chomp;print"export VPATH=\"'$VPATH'\" && export FILE=".$_." && ffmpeg -i \"\$VPATH/\$FILE\" -map 0 -vf \"yadif=1:-1:0,\$CROP\" -c:v libx264  -crf 23 -preset fast -b:a 192k -c:s copy Monk-S06E$b.mkv\n";}' > cmd.sh

export VPATH=mkv_out_02 ; ls $VPATH | perl -e '$a=8;while(<>){$a++;$b="0".$a;if($a>9){$b="".$a;}chomp;print"export FILE=".$_." && ffmpeg -i \"\$VPATH/\$FILE\" -map 0 -vf \"\$CROP\" -c:v libx264 -crf 23 -preset fast -b:a 192k -c:s copy Scrubs-S01E$b.mkv\n";}'

ls mkv_out_01/ | perl -e '$a=0;while(<>){$a++;$b="0".$a;if($a>9){$b="".$a;}chomp;print"export FILE=".$_." && ffmpeg -i \"mkv_out_01/\$FILE\" -map 0 -vf \"\$CROP\" -c:v libx264 -crf 23 -preset fast -b:a 192k -c:s copy Scrubs-S01E$b.mkv\n";}'

Interlacing in Cartoons

Detect Interlacing:

ffmpeg -i input.mp4 -vf idet -frames:v 100 -an -f rawvideo -y /dev/null

remove interlacing artifacts with:

export VPATH=Family_Guy-S05D01 ; ls $VPATH | perl -e '$a=0;while(<>){$a++;$b="0".$a;if($a>9){$b="".$a;}chomp;print"export FILE=".$_." && ffmpeg -i \"\$VPATH/\$FILE\" -map 0 -vf \"yadif=1:-1:0,\$CROP\" -c:v libx264 -crf 23 -preset fast -b:a 192k -c:s copy Family_Guy-S05E$b.mkv\n";}' | sh

-vf "yadif=0:-1:0" -c:v libx264 -flags +ilme+ildct -crf 23
-vf "yadif=0:-1:0" -flags -ilme -flags -ildct -c:v libx264 -crf 23
-vf yadif
yadif=0:-1:0 (default)
yadif=1:-1:0 (double frame)

list tv show seasons

video/tv/incoming$ find . -type f -name '*.mkv' | perl -e 'while(<>){chomp;if ($_=~/\/.*\/.*\//){}else{$a=$_;$a=~s/(-[SV][0-9][0-9]).*/$1/;print $a."\n";}}' | sort | uniq | cut -d '/' -f 3

Resetting a USB DVD Drive in Linux

If your USB DVD drive becomes unresponsive in Linux, you can attempt to reset it without rebooting your system by following these steps:

Identify the USB Device

Use the lsusb command to list all USB devices and find your DVD drive:

lsusb

Bus 002 Device 005: ID 152d:0562 JMicron Technology Corp. / JMicron USA Technology Corp. JMS567 SATA 6Gb/s bridge

Check the Device Status

Use dmesg or look at /var/log/syslog or /var/log/messages for any specific issues.

USB Device Reset

Reset the USB device by echoing a special value to the /sys directory:

echo 0 | sudo tee /sys/bus/usb/devices/usb[Bus]/[Bus]-[Device]/authorized
echo 1 | sudo tee /sys/bus/usb/devices/usb[Bus]/[Bus]-[Device]/authorized

Replace [Bus] and [Device] with the appropriate numbers from the lsusb output.

Unloading and Reloading the Kernel Module

If you know the kernel module for your USB drive, unload it:

sudo rmmod uhci_hcd

And reload it:

sudo modprobe uhci_hcd

Restarting the udev Service

Restart the udev service, which manages device nodes:

sudo service udev restart

Using usbreset

Compile and use the usbreset program for a more convenient reset.

Note: Replace uhci_hcd with the module specific to your system. Always ensure no process is using the device before attempting a reset.

Caution: Resetting kernel modules and USB devices can lead to an unstable system state. Use these commands carefully and ensure you're not affecting other essential USB devices.

If these methods do not resolve the issue, the problem may lie with the hardware of the drive, USB port, or cable. Consider trying a different port or cable.

FFMpeg

Resize

Scale, Match Vertical to Suit 720

ffmpeg -i input.avi -filter:v scale=720:-1 -c:a copy output.mkv

Subtitle Processing

ou are correct: in mpv 0.35.1, there is support for --secondary-sid (to select a second subtitle track already present in the media), but there is no option called --secondary-sub-file.

This is because mpv’s “secondary subtitle” system only applies to subtitle streams already loaded, either from the container or from a single external subtitle file loaded as primary.

What works:

If your video already contains both English and French subtitle tracks:

You can enable them both like this:

This renders both subtitle tracks simultaneously. They will stack in the same position unless you adjust one of them with options like sub-pos or sub-margin-y.

If you have two separate external subtitle files (.srt or .vtt):

By default, mpv will only load one external subtitle file, even if you specify multiple --sub-file arguments — it ignores the rest.

Workarounds:

1. Mux both subtitle files into the video container (e.g., .mkv) Use mkvmerge:

1. This displays both lines in one cue.
2. Use an mpv Lua script to load two external subtitle files. There are community Lua scripts that let you load and display two external subtitles, one at the top and one at the bottom. See the mpv Lua script resources page: https://mpv.io/resources/

Summary:

• --secondary-sub-file is not implemented.
• --secondary-sid works, but only with embedded tracks.
• For external files: either mux them into the video file, combine them manually, or use a Lua script.

If you’d like, I can help you:

• Write a shell script to mux .srt files into .mkv automatically.
• Write a minimal Lua script to load and render two .srt files in mpv.

• Then you can use --sid and --secondary-sid as above.
• Manually combine them into one subtitle file. Example:

Voice Acting

• 10 Voice Tones: https://old.reddit.com/r/TikTokCringe/comments/1at3n7a/voiceover_actor_explains10_tones_used_during_reads/
  • "im an audio for video engineer, im the person directly communicating with the voice actor to make sure the producer is happy during recording, and it really is wild the amount of times they give what is a really over the top read from their point of view, and we have to prop then up to get them to go even bigger and more exaggerated. It feels unnatural, and bizarre, but it plays well in a VO"
    • "It's like that for stage plays and performances. a persons delivery really flattens out the farther it travels so you gotta make it over-the-top"