Script for downloading a video with orbits of Jupiter&asteroids and fixing rotation on Jupiter

rotate-video.sh

#!/bin/bash
#
# Download Jupiter/asteroids video and fix Jupiter's rotation
#
# Tweet address with source video:
# https://mobile.twitter.com/AntonioParis/status/994224252961386496
#
# Required utils:
#  * curl
#  * convert
#  * ffmpeg
#


#
# Script parameters
#
video_url=https://video.twimg.com/tweet_video/Dcwxr0SVMAI6RhJ.mp4
source_video=Jupiter.mp4
dest_video=JupiterRotated.mp4
ffmpeg_log=ffmpeg.log


#
# Download source video
#
echo -n Downloading video file from URL ${video_url}
curl ${video_url} --output ${source_video} --silent

if [[ $? -ne 0 ]]; then
  echo ...Failed
  echo Error: Could not download video file
  exit 1
fi

echo ...Ok


#
# Clean temporary directory for original frames
#
if [[ -d frames ]]; then
  rm -r frames
fi

mkdir frames


#
# Extract frames from source video
#
echo -n Extracting frames from video ${source_video}
ffmpeg -i ${source_video} frames/out%03d.png 2> ${ffmpeg_log}

if [[ $? -ne 0 ]]; then
  echo ...Failed
  echo Error: Unable to extract frames from video ${source_video}
  cat ${ffmpeg_log}
  exit 1
fi

echo ...Ok


#
# Clean temporary directory for processed frames
#
if [[ -d outframes ]]; then
  rm -r outframes
fi

mkdir outframes


#
# Rotate video frames
#
counter=0
frame_count=$( ls -1q frames/*.png | wc -l )
for file in frames/*.png; do
  echo -n Process frame ${counter} of ${frame_count}

  frame_name="$( basename "${file}" )"

  convert "$file" \
    -background black \
    -rotate "$( echo "1.60 * $counter" | bc )" \
    -gravity center \
    -extent 710x710 \
    outframes/${frame_name}

  if [[ $? -ne 0 ]]; then
    echo ...Failed
    echo Error: Unable to process frame file ${file}
    exit 1
  fi

  echo ...Ok

  counter=$(( $counter + 1 ))
done


#
# Create video file from rotated frames
#
echo -n Create video ${dest_video}
ffmpeg \
  -framerate 30 \
  -start_number 0 \
  -i outframes/out%03d.png \
  -c:v libx264 -r 30 -pix_fmt yuv420p \
  -y \
  ${dest_video} 2> ${ffmpeg_log}

if [[ $? -ne 0 ]]; then
  echo ...Failed
  echo Error: Unable to create video ${dest_video}
  cat ${ffmpeg_log}
  exit 1
fi

echo ...Ok
exit 0