Creating Stop Motion Video

For fun today, Jesse constructed a stop motion scene with legos and a hand-drawn backdrop. Meanwhile, I wrote an animation process. I wrote it as two scripts: one to resize input from my camera, the other to actually animate the pictures.

My ImageMagick resize script is reasonably simple, and if you search for other animation techniques, you will see many scripts like this. To use all four cores on my processor, I fire off 5 resize jobs and then do a job wait for them to complete so that I do not bog my system down.

set -x
set -e
# ----------------------------------------------------------------#
#  resize the input directory and put it in the output directory  #
#  and also re-names the files to simple numbered format          #
# ----------------------------------------------------------------#
find 0-input/ -type f -iname "*.jpg" -printf "%f\n" \
| sort \
| while read f ; do
   echo "convert 0-input/$f -geometry 728x480! -normalize $g "
   convert "0-input/$f" -geometry 728x480! -normalize "$g" &
   i=$[ $i + 1 ]
   j=$[ $j + 1 ]
   if [ $i -eq 4 ]; then
      # wait a bit
      for job in `jobs -p`; do
         echo -n "...$job"
         wait $job 
   echo "!"
echo "done"

My animation script is not all that different from other animation scripts you can search for on google, either. However, mine does not loop, does no fades, and plays very slowly. The first ‘-r’ switch specifies how long the input frames should last, so in this case, about 750ms (1.25 frames/sec). The output frame rate is the second ‘-r’ switch.

# -f : output format
# -r : frame rate
# -i : input file pattern
now=`date +%Y-%m-%d_%H%M`
ffmpeg  -r 1.25 -i "1-resized/r-1%03d.png" -r 24 "2-animated/animation-$"

I have a post of it on my G+.