FFmpeg

Convert to GIF with color table

First pass creates a combined color table into a 16x16 PNG. This also keeps transparency.

ffmpeg -i frame_%04d.png -vf palettegen=reserve_transparent=1 palette.png

ffmpeg -i frame_%04d.png -i palette.png -r 25 -lavfi paletteuse=alpha_threshold=128 -gifflags -offsetting frames.gif

Cutting

ffmpeg -ss "01:23" -i input.mp4 -t "01:00:00" -c:a copy -c:v copy output.mp4
ffmpeg -i input.mp4 -ss "01:23" -t "01:00:00" -c:a copy -c:v copy output.mp4

• -ss: Skips to this position in the input video
  If set before the -i parameter, the skip will be aproximately based on e.g. key frames, after is an exact seek
• -t: The amount of time to encode (or copy)

Concatting

Create a file list.txt with all files to concat in the order you want:

file 'file1.mp4'
file 'file2.mp4'

The execute the command:

ffmpeg -f concat -safe 0 -i list.txt -c copy output.mp4

• Use -safe 0 to allow relative path names
• Use -c copy if the formats are compatible - otherwise specify what to convert the output to

2-Pass encoding

ffmpeg -i input.mp4 -b:v 1600k -c:v libx264 -an -pass 1 output_null.mp4
// or just pass it to /dev/null if it exists

ffmpeg -i input.mp4 -b:v 1600k -c:v libx264 -b:a 160k -c:a aac -pass 2 output.mp4

This will create temporary files on 1st pass.

Custom commands

simvalley PW-315.touch (240x240 fix with borders)

ffmpeg.exe -i {input} -vf "scale=240:-1,pad=240:240:0:24" -c:v libxvid {output}

Rip DVD

Needs libdvdcss to be installed!!!

Find the title you want by running VLC, go through the menu and then look which one is selected under Playback -> Title and replace $title with that number. This rips the title from the DVD:

mplayer dvd://$title -dvd-device /dev/sr0 -dumpstream -dumpfile file.vob

Take note of which streams are exported, especially which audio languages in which order.

Then you can convert the exported title.

ffmpeg -i file.vob \
    -map 0:v:0 -map 0:a:0 -map 0:a:1 \
    -c:v libx264 -c:a aac -b:a 160k -crf 22 \
    -metadata:s:a:0 language=deu -metadata:s:a:1 language=eng \
    output.mp4

• -i file.vob: The exported title
• -map 0:v:#: Include the #-th video stream from first input file (zero-based)
• -map 0:a:#: Include the #-th audio stream from first input file (zero-based)
• -c:v libx264: The video codec to use for the output
• -c:a aac: The audio codec to use for the output
• -b:a 160k: The audio bitrate for the output
• -crf 22: The constant rate factor (video quality) for the output (the lower the better but slower)
• -metadata:s:a:# language=???: Set thelanguage of the #-th mapped audio stream to ???
• output.mp4: The output file and its container format via extention