recursive_timelapse.sh

#!/bin/sh
# Get the final framerate for the timelapse as a command line option
FR=$1

# Create a file to hold the list of clips that we create
touch "files-$FR.txt"
# Write a header into it
echo "# $FR FPS timelapse files" > "files-$FR.txt"

# Iterate over everything in this directory
for f in $(ls); do
  # if it's a directory, recurse in and build a timelapse from the pictures in it
  if [ -d $f ] 
  then
    pushd $f
    if [ -a $FR-timelapse.mp4 ]
    then
      # if the file already exists, don't rebuild it (we could use a makefile for this)
      echo "File $f/$FR-timelapse.mp4 already exists!"
    else
      # otherwise, use ffmpeg to turn all the pictures into a videoclip
      # we just use a glob pattern instead of iterating over numeric image names, as
      # for some folders we might not start at IMG_0001.jpg
      # this is quite hacky, and might not work if the glob pattern doesn't put the
      # jpeg images in the right order. If you know the format of the filenames
      # and you know they'll start at 0001, then append "-i IMG_%04d.JPG" after "-i '*.jpog"
      ffmpeg -r $FR -pattern_type glob -i '*.JPG' -s hd1080 -vcodec libx264 -crf 18 -preset slow $FR-timelapse.mp4
    fi
    popd
    # Write the filename to the list of clips
    echo "file $f/$FR-timelapse.mp4" >> "files-$FR.txt"
    echo "Completed file from folder $f";
  fi
done

# Use ffmpeg to concatenate together the clips we just created from each folder
# Read the list of filenames from the file we wrote them to
ffmpeg -f concat -safe 0 -i files-$FR.txt -c copy full_timelapse-$FR.mp4