Convert HRRR smoke images to mp4

smoke_animation.sh

#!/bin/bash
# Create animation from HRRR NW current smoke graphics.
# Considerably more accurate than with stitching forecasts.
#
# Domains available: full,NW,NC,NE,SW,SC,SE,GreatLakes,EastCO,SEA-POR,CentralCA,CHI-DET,NYC-BOS,DCArea,SouthFL,ATL,SouthCA,VortexSE
# Fields: int,sfc,1000ft,6000ft

domain=NW
field=int
start=2022-09-12   # 2022-08-21 <- oldest available date as of 2022-09-11
end=2022-09-12     # 2022-09-12

####
n=1
dateutils.dseq $start $end -f '%Y%m%d' | while read date; do
  for hour in {00..23}; do
    # slurp and toss serving page to bypass apparent hotlinking countermeasures (?)
    #curl -s -o /dev/null "https://rapidrefresh.noaa.gov/hrrr/HRRRsmoke/displayMapUpdated.cgi?keys=hrrr_ncep_jet:&runtime=${date}${hour}&plot_type=trc1_${domain}_${field}&fcst=000&time_inc=60&num_times=49&model=hrrr&ptitle=HRRR-Smoke%20Graphics&maxFcstLen=1&fcstStrLen=-1&domain=${domain}&adtfn=1"
    wget -O "${date}${hour}-trc1_${domain}_${field}_f000.png" "https://rapidrefresh.noaa.gov/hrrr/HRRRsmoke/for_web/hrrr_ncep_jet/${date}${hour}/${domain}/trc1_${domain}_${field}_f000.png"
    ln -sf ts-"${date}${hour}-trc1_${domain}_${field}_f000.png" $n.png
    ((n++))
  done
done

ls -1 20*trc1_${domain}_${field}_f000.png | while read d; do
  stamp=$(date -d $(sed -E 's/([0-9]{4})([0-9]{2})([0-9]{2})([0-9]{2}).*/\1-\2-\3T\4-00:00/' <<<$d) '+%b %d %H:00 %Z %Y')
  convert -fill black -pointsize 20 -gravity NorthWest -draw "text 460,32 '$stamp'" $d ts-$d
done

# lazy helper for ffmpeg sequencing
#n=1; ls -1 ts-${date}${hour}-trc1_${domain}_${field}_f000.png | while read a; do ln -sf $a $n.png; ((n++)) done

anim=$(date '+%Y%m%d%H%M')-trc1_${domain}_${field}_f000.mp4
ffmpeg -framerate 12 -i %d.png -c:v libx264 -r 30 $anim

# cleanup symlinks for future runs
find -maxdepth 1 -type l -delete

echo -e "\n\nFinished: mpv -loop $anim"

mpv -loop $anim