ffmpeg hints

# image at the center of the video
# https://stackoverflow.com/questions/10918907/how-to-add-transparent-watermark-in-center-of-a-video-with-ffmpeg
ffmpeg -i small.mp4 -i avatar.png -filter_complex "overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -codec:a copy output.mp4

# with transparency
# https://stackoverflow.com/questions/38753739/ffmpeg-overlay-a-png-image-on-a-video-with-custom-transparency
ffmpeg -i small.mp4 -i avatar.png -filter_complex "[1:v]format=argb,colorchannelmixer=aa=0.5[zork];[0:v][zork]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -codec:a copy output.mp4

# text
# https://stackoverflow.com/questions/17623676/text-on-video-ffmpeg
ffmpeg -i small.mp4 -vf drawtext="fontfile=/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf: text='Hello World': fontcolor=white: fontsize=24: box=1: [email protected]: boxborderw=5: x=(w-text_w)/2: y=(h-text_h)/2" -codec:a copy output.mp4

# text with image
ffmpeg -i small.mp4 -i avatar.png -filter_complex '[1:v]drawtext=fontfile=/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf: text="Hello World": fontcolor=white: fontsize=24: box=1: [email protected]: boxborderw=5: x=(w-text_w)/2: y=(h-text_h)/2[zork];[0:v][zork]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2' -codec:a copy output.mp4

# only first 3 seconds
# https://superuser.com/questions/683643/how-to-add-my-logo-for-the-first-30-seconds-in-a-video-with-ffmpeg
ffmpeg -i small.mp4 -i avatar.png -filter_complex "overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:enable=between(t\,0\,3)" -codec:a copy output.mp4

# several
ffmpeg -i SampleVideo.mp4 -i avatar.png -i avatar1.png -filter_complex "[0:v][1:v]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:enable=between(t\,0\,10)[zork];[zork][2:v]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:enable=between(t\,10\,20)" -codec:a copy output.mp4

# fade in effect for image
# https://superuser.com/questions/833232/create-video-with-5-images-with-fadein-out-effect-in-ffmpeg
ffmpeg -i small.mp4 -loop 1 -i avatar.png -filter_complex "[1:v]fade=t=in:st=0:d=1:alpha=1[zork]; [0:v][zork]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2" -codec:a copy -shortest output.mp4

# fade in effect for text
ffmpeg -i small.mp4 -filter_complex "drawtext=fontfile=/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf: text='Hello World': fontcolor_expr='ffffff%{eif\\: if(between(t\, 0\, 3)\, t*85\, 255) \\: x \\: 2}': fontsize=24: box=1: [email protected]: boxborderw=5: x=(w-text_w)/2: y=(h-text_h)/2" -codec:a copy output.mp4



ffmpeg -i SampleVideo.mp4 -loop 1 -i avatar.png -filter_complex "[1:v]format=argb,colorchannelmixer=aa=0.5, fade=t=in:st=0:d=1:alpha=1, fade=t=out:st=14:d=1:alpha=1, drawtext=fontfile=/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf: text='Hello World': fontcolor_expr='ffffff%{eif\\: if(between(t\, 0\, 1)\, t*255\, if(between(t\, 6\, 7)\, 255+255*(6-t)\, 255)) \\: x \\: 2}': fontsize=24: box=1: boxcolor=white@0: boxborderw=5: x=(w-text_w)/2: y=(h-text_h)/2 : enable=between(t\,0\,7), drawtext=fontfile=/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf: text='And other People': fontcolor_expr='ffffff%{eif\\: if(between(t\, 8\, 9)\, -(8-t)*255\, 255) \\: x \\: 2}': fontsize=24: box=1: boxcolor=white@0: boxborderw=5: x=(w-text_w)/2: y=(h-text_h)/2 : enable=between(t\,8\,15)[zork]; [0:v][zork]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:enable=between(t\,0\,15)" -codec:a copy -shortest output.mp4

ffmpeg -i small.mp4 -i t%d.png -filter_complex "[1:v]format=argb,colorchannelmixer=aa=0.7[zork];[0:v][zork]overlay=(main_w-overlay_w)/2:(main_h-overlay_h)/2:enable=between(t\,0\,3)" -codec:a copy output.mp4

# video to frames (first second)
ffmpeg -t 1 -i wrk.mp4 -r 25 o%d.jpg