Collection of useful FFMPEG techniques

ffmpeg-commands.sh

# ------ IMAGE SEQUENCE ------ #

# Create QuickTime-friendly .MOV from a sequence of PNGs
# In this example they start with “test…”
# Note: The crop filter is so we don’t need to worry about input files 
# being divisible by two. If they’re not, we crop them to fit
# with `-vf "crop=trunc(iw/2)*2:trunc(ih/2)*2"`

ffmpeg -r 60 -pattern_type glob -i "test*.png" -vf "crop=trunc(iw/2)*2:trunc(ih/2)*2" -vcodec libx264 -crf 5 -pix_fmt yuv420p output.mov


# ------ CONVERT TO MP4 ------ #

# For max compatibility, use profile option. May increase bit rate “quite a bit”: 
# Disable audio stream with -an option. -pix_fmt yuv420p is for Apple Quicktime support.

# Basic:

ffmpeg -i logo.mov -vcodec libx264 -pix_fmt yuv420p -profile:v baseline -level 3 -an logo.mp4

# With filters:

ffmpeg -i logo.mov -vcodec libx264 -pix_fmt yuv420p -profile:v baseline -level 3 -vf "pad=width=2456:height=1382:x=-1:y=-0:color=#000000, fillborders=left=644:right=644:mode=smear, scale=1000:-1" -an logo.mp4


# ------ CONCATENATE ------ #

# Combine multiple clips into one.
# There are multiple ways to do this.
# - Docs: https://trac.ffmpeg.org/wiki/Concatenate
# - SO:   https://stackoverflow.com/a/11175851

# Prefer to use the "concat demuxer"
# Per SO thread: "Use this method when you want to avoid a re-encode and your format does not support file-level concatenation (most formats used by general users do not)."

# NOTE: Am using printf here so we can declare the inputs within a simple one-liner.
# Most examples have the user instead create a dedicated .txt file listing the files.

ffmpeg -f concat -safe 0  -i <(printf "file input-1.mp4 \n file input-2.mp4") -c copy output.mp4


# ------ COMPRESS ------ #

# Filters crop and scale are just examples. 
# Can remove the -vf lines if we don't want to apply filters.

# Create WebM
ffmpeg -y -i input.mp4 -c:v libvpx-vp9 -pass 1 -b:v 0 -crf 33 -threads 8 -speed 4 \
  -tile-columns 6 -frame-parallel 1 \
  -an -f webm /dev/null

ffmpeg -y -i input.mp4 -c:v libvpx-vp9 -pass 2 -b:v 0 -crf 33 -threads 8 -speed 2 \
  -vf crop=400:300 scale='min(1000, iw)':-2 \
  -tile-columns 6 -frame-parallel 1 -auto-alt-ref 1 -lag-in-frames 25 \
  -c:a libopus -b:a 64k -f webm output.webm

# Create Mp4
ffmpeg -y -i input.mp4 -vcodec libx264 -pix_fmt yuv420p -profile:v baseline -level 3 \
  -vf crop=400:300 scale='min(1000, iw)':-2 \
  -an output.mp4


# ------ ROTATE ------ #

# SO: https://stackoverflow.com/questions/3937387/rotating-videos-with-ffmpeg

# Rotate without re-encoding
# (requires player that supports rotation metadata)
ffmpeg -i input.mp4 -map_metadata 0 -metadata:s:v rotate="90" -codec copy output.mp4

# Check metadata first
# (am not sure if this always works reliably)
ffmpeg -i input.mp4 2>&1 | grep rotate


# ------ TIME ------ #

# Docs: https://trac.ffmpeg.org/wiki/Seeking

# FMPEG time unit syntax:
# Docs: https://trac.ffmpeg.org/wiki/Seeking#Timeunitsyntax
# "Note that you can use two different time unit formats: sexagesimal (HOURS:MM:SS.MILLISECONDS, as in 01:23:45.678), or in seconds. If a fraction is used, such as 02:30.05, this is interpreted as "5 100ths of a second", not as frame 5. For instance, 02:30.5 would be 2 minutes, 30 seconds, and a half a second, which would be the same as using 150.5 in seconds."

# Trim time to specified length, from specified start point.
# This clip would be 5.75 seconds long.
# -ss: Start time of the clip
# -to: Duration of the clip
# -c copy: Trim via stream copy (fast and performant)

ffmpeg -ss 00:01:00 -i input.mp4 -to 00:06.75 -c copy output.mp4

# Trim from start to specified time
# (same as above, but leaving out -s sets it to default 00:00)
# -to: End time of the clip
# -c copy: Trim via stream copy (fast and performant)

ffmpeg -i input.mp4 -to 00:06.75 -c copy output.mp4