/*
 * title "Editing School Day 3: Overlay"
 * author "Dylan Lom"
 * date "2021-04-30"
 * link stylesheet /main.css
 */

# $(echo "$title")

Simple one, overlay an image at a particular time.

First I figured out the resolution of base.mp4 with `ffprobe` -- there's
probably a way to get only the res but I just dug through the output to find it

    ffprobe base.mp4

The resize the image to fit the video. I didn't overly care if part of it was
cropped so I just resized it to the largest dimension of the video

    convert cat.jpg -resize x480 cat_resized.jpg
   
Use the `overlay` filter, at position 0,0 when `t` is `greater than or equal` `4`s

    ffmpeg -i base.mp4 -i cat_resized.jpg \
        -filter_complex "overlay=0:0:enabled='gte(t, 4)'" \
        out.mp4