segmenter.sh

#!/bin/bash

. ./diycam.config
mkdir -p $upload_dir

# monitor a directory for new files with a given pattern being written; we avoid touching the most recent file, since ffmpeg is likely writing to it
segmenter() {
	camera=$1
	echo watching $monitor_dir/$camera
	while true; do
		# get all but the last file (which we presume ffmpeg to be processing)
		files=($monitor_dir/cam${camera}_*)
		numfiles=${#files[@]}
		if (( $numfiles >= 1 )); then
			unset files[-1]
		fi	
		# process each of the files we found
		for file in ${files[@]}; do
			# skip directories, e.g. stray events dirs
			if [[ -d $file ]]; then
				continue
			fi

			segment=`basename $file`
        		#echo found $segment
	     		if [ -n "$segment" ]; then
				process_segment $segment || echo "Processing $segment failed"
			else 
				break
        		fi
		done
		# pause and let another camera's output be processed
		sleep 30
	done
}

# process a segment for events; any detected motion events will be moved to the upload folder
# the original segment video is deleted
process_segment() {
	segment=$1
	segmentdir=${monitor_dir}/$segment-events
        mkdir $segmentdir
	#echo "env/bin/dvr-scan -i ${monitor_dir}/$segment -m copy -l ${sensitivity}s -k 17 -tb ${sensitivity}s -d $segmentdir -b CNT"
	echo Scanning $segment
	if (( $skip_frames > 0 )): then
		skip="-fs $skip_frames"
	fi

        env/bin/dvr-scan -i ${monitor_dir}/$segment -m ffmpeg $skip -l ${sensitivity}s -k $kernel -tb ${sensitivity}s -d $segmentdir -b CNT --quiet || error_file ${monitor_dir}/$segment || return 1
        # for each event video, extract thumbnail and move to the uploads folder, where it'll be processed
        for file in `find $segmentdir -type f`; do
        	#echo processing $file
                filename=`basename $file`
                thumbnailname=${filename}_thumbnail.jpg
		thumbnailpath=$segmentdir/$thumbnailname
                # XXX need better way of including sensitivity here
                ffmpeg -hide_banner -loglevel error -i $file -ss 00:00:0$sensitivity -frames:v 1 $thumbnailpath || exit 1
		echo Produced $file
		mv $file $upload_dir
		mv $thumbnailpath $upload_dir
       	done

        rm -fr $segmentdir
        rm ${monitor_dir}/$segment
        echo Finished processing $segment
}

error_file() {
	file=$1
	mkdir -p $error_dir
	echo error processing $file
	mv $file $error_dir
	return 1
}

# kick off a segmenter per camera
for camera in ${!cameras[@]}; do
	echo $camera
	segmenter $camera &
done