#!/bin/bash

#cutting the video

INFILE1="../2017_Photos/2017_11_14_gensac_parapente/VID_20171114_135427.3gp"
START_TIME1="0:39"

#de 39 à 53 =14 secondes
#retournement à 43, soit apres 4 secondes

INFILE2="../2017_Photos/2017_11_14_gensac_parapente/GOPR0844.MP4"

#https://www.ffmpeg.org/doxygen/0.7/parseutils_8c-source.html#l00487
#d'après 00487 int av_parse_time(int64_t *timeval, const char *datestr, int duration)
#la partie fractionnaire de secondes est exprimée en us
START_TIME2="2:18.500000"
#retournement à 2:23

DURATION="0:00:14"

TMPDIR="/tmp/myvideo/"
rm -rf $TMPDIR
mkir -p $TMPDIR

#INTERMEDIATEFILE="cutted.mkv"
#OUTFILE="res.mkv"
#ffmpeg -i $INFILE -ss $START_TIME -t $DURATION -c copy $INTERMEDIATEFILE

#converting the video to images 1
mkdir -p $TMPDIR/imgs1
avconv -i $INFILE1 -r 30 -f image2 -ss $START_TIME1 -t $DURATION  $TMPDIR/imgs1/im-%06d.bmp


#converting the video to images 2
mkdir -p $TMPDIR/imgs2
avconv -i $INFILE2 -r 30 -f image2 -ss $START_TIME2 -t $DURATION  $TMPDIR/imgs2/im-%06d.bmp

#concatenate the images
mkdir -p $TMPDIR/imgs3

rm $TMPDIR/list
#ls -c1 *.pgm | sort >>list
#genere la liste ordonnée des fichiers pgm du dossier dans un fichier list
find $TMPDIR/imgs1 -type f -printf "%f\n" | grep bmp | sort >>$TMPDIR/list

	
#pour chaque ligne de list
cat $TMPDIR/list | while read line
do
echo ${line}
convert $TMPDIR/imgs1/${line} $TMPDIR/imgs2/${line} +append $TMPDIR/imgs3/${line}	
rm $TMPDIR/imgs1/${line} 
rm $TMPDIR/imgs2/${line}
done

#extrait la piste audio
rm  $TMPDIR/audio.mp3
avconv  -i $INFILE1  -ss $START_TIME1 -t $DURATION $TMPDIR/audio.mp3

#generate the movie file from file with name pattern: out-img0001.png
avconv -i $TMPDIR/audio.mp3 -i $TMPDIR/imgs3/im-%06d.bmp -f avi -vcodec mpeg4 -b 4000k -g 300 -bf 2 -y ./video.mpg