extra fixes and cleanup

Author: geolaw

image_stacker.sh

@@ -1,10 +1,12 @@
 #!/bin/bash
 
 # requires ffmpeg, ffprobe, imagemagick's convert and vidstab python module , python3
+# credit to https://inphotos.org/2015/11/28/more-fun-with-long-exposure-stacking-of-photos/
+
 
 # print usage if no params
 if [ -z $1 ]; then
-    echo "usage: $0 -f <video file> -F <convert evaluate filter > -r <factor to reduce fps captures> -s <start mm:sec.fraction> -S <stabilize video first 0/1>"
+    echo "usage: $0 -f <video file> -F <convert evaluate filter > -r <factor to reduce fps captures> -s <start mm:sec.fraction> -S <stabilize video first 0/1> -d <duration of video to capture>"
     echo "for a list of all convert filters, run convert -list evaluate "
     exit
 fi
@@ -16,19 +18,24 @@ for i in ffmpeg ffprobe convert; do
         exit;
     fi
 done
-
+pid=$$
 until [[ -z $1  ]]; do
     case $1 in
-	-f)  filename="$2"; shift ;;  # quote this in case video contains spaces
-	-F)  filter=$2; shift ;;
-	-r)  reduce_factor=$2; shift ;;
-	-s)  start_time=$2; shift ;;
-	-S)  stabilize=$2; shift ;;
+        -f)  filename="$2"; shift ;;  # quote this in case video contains spaces
+        -F)  filter=$2; shift ;;
+        -r)  reduce_factor=$2; shift ;;
+        -s)  start_time=$2; shift ;;
+        -d)  duration_secs=$2; shift ;;
+        -S)  stabilize=$2; shift ;;
     esac
     shift
 done
 
 # need to check the basic requires params of $filename and $filter are all there
+if [ -z $filename ] || [ -z $filter ]; then
+    echo "At least a filename and filter are required"
+    exit;
+fi
 
 newvid=new.mp4
 if [ -z $stabilize ] || [ $stabilize == 0 ]; then
@@ -51,11 +58,32 @@ else
     python3 -m vidstab -i "$filename" -o $newvid
 fi
 
+# optional -s option  to start slicing at a certain point in the video - e.g. instable video for the first 10 seconds, pass 11 to start slicing at 11 seconds in.
+if [ -z  $start_time ]; then
+    start_time="-ss 0"
+else
+    start_time="-ss $start_time"
+fi
+
+# duration - need to
+if [ ! -z  $duration_secs ]; then
+    duration_secs="-t $duration_secs"
+fi
+
+
+# if we get start_time and duration_secs, run those through ffmpeg to create a new video for proper calculations below
+if [ "$start_time" != "-ss 0" ]  || [ "$duration_secs" != "" ]; then
+    mv $newvid tmp_$newvid
+    echo "Generating new video based on start time of $start_time and duration : $duration_secs"
+    ffmpeg -loglevel quiet $start_time $duration_secs -i tmp_$newvid -q:v 1  $newvid
+fi
+
+# main image processing
 TMPDIR="tmp_$$"
 
 if [ -e $TMPDIR ]; then
-	rm -rf $TMPDIR
-	mkdir $TMPDIR
+    rm -rf $TMPDIR
+    mkdir $TMPDIR
 else
     mkdir $TMPDIR
 fi
@@ -70,37 +98,35 @@ fps_string=$(grep Stream $TMPDIR/ff_output);
 
 # probably won't have a hour or minute long video for this, so we just strip out the last digits
 duration=$(echo $duration_string| sed 's/.*Duration.*[0-9][0-9]:[0-9][0-9]:\([0-9][0-9]\.[0-9][0-9]\),.*/\1/');
-fps=$(echo $fps_string |sed 's/.*\([0-9][0-9]\) fps.*/\1/');
+fps=$(echo $fps_string |sed 's/.*, \(.*\) fps.*/\1/');
+fps=$(echo "scale=0; $fps/1"|bc); # drop the decimal if there is one
 
 # optional $reduce_factor -  to decrease the number of slices - e.g. for 30 fps and 2 $reduce_factor, will capture 15 slices per second
 if [ ! -z $reduce_factor ]; then
-	images_per_sec=$(echo "$fps / $reduce_factor" | bc);
-    else
-        images_per_sec=$fps
-fi
-
-# optional -s option  to start slicing at a certain point in the video - e.g. instable video for the first 10 seconds, pass 11 to start slicing at 11 seconds in.
-if [ -z  $start_time ]; then
-	start_time="-ss 0"
+    images_per_sec=$(echo "$fps / $reduce_factor" | bc);
 else
-	start_time="-ss $start_time"
+    images_per_sec=$fps
 fi
 
 frames=$(echo "scale=2;$duration * $images_per_sec" | bc);
 echo "Video is $duration seconds long at $fps fps - - will capture $images_per_sec images per second - which  should generate $frames images - start at $start_time"
 # note that the -r $fps option placement is important.  If places BEFORE the -i it affects the input file rate
-ffmpeg $start_time -loglevel quiet -stats -hide_banner -i "$newvid" -q:v 1 -r $images_per_sec   $TMPDIR/slice_%04d.png
+ffmpeg -loglevel quiet -stats -hide_banner -i "$newvid" -q:v 1 -r $images_per_sec   $TMPDIR/slice_%04d.png
 
 # cd into $TMPDIR so all the output is generated in the $TMPDIR
 cd $TMPDIR
 
-newname="${filename%.*}_stacked.png"
+newname="${filename%.*}_stacked_$filter_$pid.png"
 #nice convert  -monitor -flatten slice* -evaluate-sequence $i output_$i.png
-time convert  slice* -evaluate-sequence $filter ../$newname
-exit;
+if [ $filter == "average" ]; then
+    time convert  slice* -average ../$newname
+else
+    time convert  slice* -evaluate-sequence $filter ../$newname
+fi
 if [ "$?" == "0" ]; then
     cd ..
     rm -r $TMPDIR
     rm $newvid
 fi
 ls -la $newname
+feh $newname