ffmpeg Commands

gistfile1.txt

# Crop at 1920x1080 video to a square - iMovie exports at 1920x1080
ffmpeg -i example.mp4 -vf "crop=1080:1080:420:0" example_square.mp4

# Add subtitles to the video
# MarginV will push the margin further up the screen - e.g. MargvinV=25 (which makes more space for overlay on the bottom)
ffmpeg -i Patriot_square.mp4 -vf "subtitles=patriot.srt:force_style='Fontname=American Typewriter,OutlineColour=&H00000000,BorderStyle=3,Outline=1,Shadow=0,MarginV=20'" Patriot_square_with_subs.mp4

# Horizantal stack with the right side flipped upside-down
# Note, since there is only one input and output filter_complex shouldn't be needed here.
# I found this in an example on SO, but as I've learned more filter_complex is need if there is more than one
# input or output: https://ffmpeg.org/ffmpeg.html#Simple-filtergraphs
ffmpeg -i dancing_mickey__edit_8.mov -filter_complex "[0:0]crop=iw/2:ih:iw/4:0[left]; [0:0]crop=iw/2:ih:iw/4:0, vflip[right]; [left][right]hstack=inputs=2" dancing_mickey_hstack_flip.mov

# Blend videos using 1x1 checkerboard. Example from documentation, but shows how input should work
ffmpeg -i rapping_first_4_bars_square.mp4 -i patriot_square_first_4_bars.mp4 -filter_complex "\
  [0:v][1:v]blend=all_expr='if(eq(mod(X,2),mod(Y,2)),A,B)'\
" -vsync vfr blended.mp4

# Blend using 4x4 checkerboard.
# Can "4" as  below to change the size of the checkers
# Per https://stackoverflow.com/a/76785518
ffmpeg -i rapping_first_4_bars_square.mp4 -i patriot_square_first_4_bars.mp4 -filter_complex "[0:v][1:v]blend=all_expr='if(eq(mod(floor(X/4),2),mod(floor(Y/4),2)),A,B)'"  -vsync vfr blended_3.mp4

# This will blend keeping more of "B" (the second video)
ffmpeg -i rapping_first_4_bars_square.mp4 -i patriot_square_first_4_bars.mp4  -filter_complex "\
  [0:v][1:v]blend=all_expr='if(eq(mod(X,8),mod(Y,8)),A,B)'\      
" -vsync vfr blended_5.mp4

# Flicker the image into the video between frames 240 and 260 2 out of every 8 frames
ffmpeg -i [email protected] \
  -i [email protected] \
  -filter_complex "overlay=enable='if(between(n, 240, 260), lt(mod(n, 8), 2))'" out.mov

# Concatenate two videos
# contents of files_to_combine.txt:
# file '1_go.mov'
# file '2_where_to.mov'
# These args are fast and prevent decoding and re-encoding
ffmpeg -f concat -safe 0 -i files_to_combine.txt -c copy 1_2.mov