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Concatenate two or more files

Create a list file with them, example content for list.txt

file file1.avi
file file2.avi
file file3.avi
...

Concatenate them in a single output.avi file

ffmpeg -f concat -i list.txt -c copy "output.avi"

that's it...

Change video resolution

To change video resolution on a file just use these flags

# FullHD video resize (1920x1080) from 4K video but it works from lower resolutions too
# "-2" instead of "1080" just keep up current resolution (4:3 / 16:9 / 16:10 / ...) by using just one dimension
ffmpeg -i input.mkv -vf scale=1920:-2 output.mkv

Remove tracks (Audio/Video) from file

# Gather information from file
ffpmeg -i filename.mkv

# Keep/Select only the required tracks, might be video or audio
ffmpeg -i filename.mkv -map 0:0 -map 0:1 -acodec copy -vcodec copy filenamenew.mkv

Reduce file size with encoding

Entering down in the ffmpeg rabbit hole flags and options requires a certain amount of time and insanity.
To better figure all those nice features aimed to downsampling files here is as quick recap:

  • -i inputFile.mkv
    Obviously the file in, outputFile.xxx is always the last parameter
  • -vcodec libx264
    Tells it to use the standard H.264 video codec
  • -c:v libx265
    Uses the H.265 codec. Maintains a "good" quality at a high compression ratio
  • -crf 23
    This is the most important number, the scale goes from 0 to 51.
    23/24 is the default and usually a great balance. If 23 is still too big, try 26 or 28
    • Lower number = Higher quality, larger file size
    • Higher number = Lower quality, smaller file size
  • -preset slow
    Three interesting presets available: medium, veryfast, ultrafast but also: fast, medium, slow (takes longer)
  • -c:a ac3 -b:a 640k
    Converts the likely-massive DTS-HD/TrueHD audio track to a standard 5.1 surround sound format at a high bitrate
  • -c:a aac -ac 2 -b:a 160k (160k: Stereo audio only)
    • -c:a aac
      Switches the audio codec to AAC (Advanced Audio Coding)
    • -ac 2
      Audio Channels flag. Downmix the 5.1/7.1 source into 2-channel stereo. ffmpeg handles the logic to avoid loosing center-channel dialogue
    • -b:a 160k
      Set bitrate to 160kbps. For a stereo AAC track
      • 160k is considered "transparent" (high quality)
      • 640k is needed for 5.1.
  • -c:s copy
    Simply copy subtitle tracks without modifying them
  • -filter:a "loudnorm"
    When downmixing 5.1 surround sound to 2.0 stereo, the dialogue can sometimes end up sounding very quiet compared to the explosions/music. If the output audio is too "thin", adding this filter would normalize the volume
  • -map 0:v:0 -map 0:a:0, -map 0:v:0 -map 0:a:0 -map 0:s?:
    Grab the first video track, the first audio track, and all subtitle tracks, the ? prevents the command from failing if there are no subtitles
  • -map_metadata -1
    High-quality MKV rips often contain chapters, tags, and even embedded cover art. This flag nukes them all for a cleaner, slightly smaller file.
# Force it to use h264
ffmpeg -i inputFile.mkv -vcodec libx264 -crf 23 -preset veryfast -c:a copy outputFile.mp4

# Also interesting is the h265 HEVC encoding
# H265 is highly efficient, often saving 50% more space than H264
# older devices (old TVs/computers) might struggle to play it
ffmpeg -i inputFile.mkv -vcodec libx265 -crf 28 -preset medium outputFile.mp4

# When h265 is accepted this is a quite good definitive command
ffmpeg -i inputFile.mkv -map 0:v:0 -map 0:a:0 -map 0:s? -c:v libx265 -crf 24 -preset slow -c:a aac -ac 2 -b:a 160k -c:s copy -map_metadata -1 outputFile.mkv

Convert 1080p -> 720p

Convert files in a directory from 1080p to 720p

#!/usr/bin/env bash
#
# Utility for converting src/* from 1080p to 720p
#
# ffmpeg -y -i input -c:v libx264 -b:v 2600k -pass 1 -an -f null /dev/null && \
# ffmpeg -i input -c:v libx264 -b:v 2600k -pass 2 -c:a aac -b:a 128k output.mp4
DIRSRC=/tmp/tmp/src/*
DIRDEST=/tmp/tmp/dst

for FILE in $DIRSRC; do
    FILEDST=`basename "$FILE"`
    ffmpeg -i "$FILE" -vf scale=-1:720 -c:v libx264 -crf 18 -preset veryslow -c:a copy "$DIRDEST/$FILEDST"
done

Convert from Canon .mov file to a more modern .mp4 file

# Input    input.mov
# Output   output.mp4
ffmpeg -fflags +genpts -f avi -i input.mov -map 0:v:0 -map 0:a:0 -c:v libx264 -crf 23 -pix_fmt yuv420p -c:a aac -ar 44100 -b:a 128k output.mp4

Crop video stream to the upper left region

Crop a full screen video capture to the upper left part of it (1920x1080) and remove audio tracks too, useful for bigger screens and demos

ffmpeg -i inputVideo.mkv -vf "crop=1920:1080:0:0" -c:v libx264 -an outputVideo.mp4

Convert webm to mp3

# -vn      # disable video
# -ab xxx  # audio bitrate
# -ar xxx  # audio sampling rate (in Hz)
ffmpeg -i filename.webm -vn -ab 128K -ar 44100 filename.mp3

wav to mp3

# Classic codec, no frame adjustments
ffmpeg -i myfile.wav -acodec mp3 myfile.mp3

# Changing sound bitrate too
ffmpeg -i track01.wav -acodec mp3 -ab 64k track01.mp3

# lame does it too (and changes the bitrate in the middle if it's needed)
lame -b 128 input.wav output.mp3

Play files

# Play mp3 file, full text command line, no display needed
ffplay -nodisp filename.mp3

Office365 - Download Videos

Download View Only Video From Microsoft Sharepoint / Streams

Force download from Share Point or Stream

Chrome/Edge(F12) -> Inspector -> Network -> videomanifest?privode

  • Open the page with the video you want to download
  • Ctrl+Shift+C to open the browser inspector
  • Go to the Network tab, select filter to gather specific URL
    • Search for videomanifest?provider=... in the filter field
    • Copy that link address, this is usually a h264 direct stream,
      it should be something looking like: 
          videomanifest?provider=spo...
  • Use ffmpeg to download the video. Command syntax: 
        ffmpeg -i "https://videoManifestFullURL" -codec copy /tmp/download.mp4