ffmpeg_commands_web_streaming_videojs

#!
# These are the ffmpeg commands I use to convert a movie into multiple formats, and aspect ratios.
# Used as background video for a web app.
# The goals is efficient streaming to every device screen size in the browser. 
# Using video.js formats: MP4, WebM, OGV
#
# Using myvideo.mp4. Dimensions are 1280px by 720px.
#

# STOP! Don't use these dimensions! Instead, decide on dimensions that work well with your site, and media queries.
# Crop the video. Save as myvideo_1170x_333y.mp4. Dimensions are 1170px x by 333px y. 55:185 means start crop from the left:top.
    ffmpeg -i myvideo.mp4 -filter:v "crop=1170:333:55:185" myvideo1170x333y.mp4
# Crop again for vertical mobile devices
    ffmpeg -i myvideo.mp4 -filter:v "crop=513:720:383:0" myvideo513x720y.mp4

#
# Loop though the next two commands for each crop size. Generates other formats (WebM, OGV).

# Save mp4 as WebM
    ffmpeg -i myvideo_1170x_333y.mp4 -c:v libvpx -crf 10 -b:v 1M -c:a myvideo1170x333y.webm

# Save mp4 as ogv
    ffmpeg -i myvideo_1170x_333y.mp4 -c:v libtheora -c:a libvorbis myvideo1170x333y.ogv

#! Congrats! You're Done

#
# OTHER HELPFUL COMMANDS

# Install ffmpeg. This command will install ffmpeg with needed codecs on mac using homebrew.
    brew install ffmpeg --with-libvpx --with-libvorbis --with-theora

# Just a useful command. For when you download .mp4 files from youtube, and want to add silent acc audio so they will import into iMovie.
  ffmpeg -f lavfi -i aevalsrc=0 -i spaceshuttle.mp4 -vcodec copy -acodec aac -map 0:0 -map 1:0 -shortest -strict experimental -y newspace_shuttle.mp4