Fancy Filtering Examples

Video

cellauto

ffplay -f lavfi -i cellauto=rule=110

Other interesting cellauto rule values: 9, 18, 22, 26, 30, 41, 45, 50, 54, 60, 62, 73, 75, 77, 82, 86, 89, 90, 97, 99, 101, 102, 105, 107, 109, ​110 (default), 124, 126, 129, 131, 133, 135, 137, 145, 146, 149, 150, 151, 153, 154, 161, 167, 169, 181, 182, 183, 193, 195, 210, 218, 225.

life

ffplay -f lavfi -i life=s=300x200:mold=10:r=60:ratio=0.1:death_color=#C83232:life_color=#00ff00,scale=1200:800:flags=16

ffplay -f lavfi -i life=s=640x480:mold=10:r=100:ratio=0.1:death_color=blue:life_color=#00ff00,boxblur=2:2

mandelbrot

ffplay -f lavfi -i mandelbrot

mirror effect

ffplay -i INPUT -vf "crop=iw/2:ih:0:0,split[tmp],pad=2*iw[left]; [tmp]hflip[right]; [left][right] overlay=W/2"

video channel separation effect with lut filter

RGB version

ffmpeg -f lavfi -i testsrc=d=10 -filter_complex "split=4[a][b][c][d];[a]pad=iw*4:ih[w];[b]lutrgb=g=0:b=0[x];[c]lutrgb=r=0:b=0[y];[d]lutrgb=r=0:g=0[z];[w][x]overlay=w:0[wx];[wx][y]overlay=w*2:0[wxy];[wxy][z]overlay=w*3:0" -f nut - | ffplay -

YUV version

ffmpeg -f lavfi -i testsrc -filter_complex "split=4[a][b][c][d];[a]pad=iw*4:ih[w];[b]lutyuv=u=128:v=128[x];[c]lutyuv=y=0:v=128[y];[d]lutyuv=y=0:u=128[z];[w][x]overlay=w:0[wx];[wx][y]overlay=w*2:0[wxy];[wxy][z]overlay=w*3:0" -f nut - | ffplay -

histogram

ffplay -f lavfi -i mandelbrot -vf "split=4[a][b][c][d],[d]histogram=display_mode=overlay:level_height=244[dd],[a]histogram=mode=waveform:waveform_mode=row:display_mode=overlay[aa],[b]histogram=mode=waveform:waveform_mode=column:display_mode=overlay[bb],[c]pad=iw+256:ih+256[cc],[cc][aa]overlay=x=W-256[ccc],[ccc][bb]overlay=y=H-256[x],[x][dd]overlay=y=H-256:x=W-256"

waveform

Split the waveform mode of the histogram filter to show broadcast range of the waveform (y values between 16 and 235) in green and out of broadcast range in red.

ffplay -i http://download.blender.org/peach/bigbuckbunny_movies/big_buck_bunny_480p_surround-fix.avi  -vf "split[a][b];[a]format=gray,histogram=mode=waveform:waveform_mode=column,vflip,split[c][d];[b]pad=iw:ih+256[padded];[c]geq=g=1:b=1[red];[d]geq=r=1:b=1,crop=in_w:220:0:16[mid];[red][mid]overlay=0:16[wave];[padded][wave]overlay=0:H-h"

Audio

aevalsrc

Making some random "musical" keys:

% cat expr
# floor(t): 0 0 0 0 0 ... 1 1 1 1 1 ... 2 2 2 2 2
#  => set a random key when floor(t) changes
if(eq(floor(t),ld(2)),
    st(0,random(4)*3000+1000));

# the next value to compare floor(t) with
st(2,floor(t)+1);

# mod(t,1) makes t always in the range [0;1) for each key
st(1,mod(t,1));

# 0.6*... + 0.4*... for "echo" effect
# exp() to mitigate the sound according to the time
(0.6*sin(1*ld(0)*ld(1))+
 0.4*sin(2*ld(0)*ld(1)))*exp(-4*ld(1))

And to test it:

ffplay -f lavfi -i "aevalsrc=$(grep -v '^#' expr|tr -d '\n'|sed 's/\([,;]\)/\\\1/g')"

showwaves and showspectrum

Given the audio file april.flac:

ffplay -f lavfi 'amovie=april.flac,asplit=3[out1][a][b]; [a]showwaves=s=640x240,pad=iw:ih*2[waves]; [b]showspectrum=s=640x240[spectrum]; [waves][spectrum] overlay=0:h [out0]'