Multi threading

modules/mp4_to_jpg.sh

@@ -1,11 +1,16 @@
 #!/bin/bash
 # Options
 PLAYLIST_URL=https://youtube.com/playlist?list=PLwlIgd6_8FLJqgvIgtUye8Jz2jSKLrCAI
-IMAGE_NUM=10
+IMAGE_NUM=20
 # ----- Start script -----
 # get playlist name
 PLAYLIST_NAME=$(yt-dlp --no-warnings --dump-single-json --playlist-end 1 $PLAYLIST_URL | jq -r '.title')
 echo "Playlist Name:" $PLAYLIST_NAME
+# get CPU threads
+CPU_THREADS=$(grep processor /proc/cpuinfo | wc -l)
+RUN_THREADS=$(($CPU_THREADS/2))
+echo "cpu threads:$CPU_THREADS"
+echo "run threads:$RUN_THREADS"
 # get script dir
 SCRIPT_DIR=$(cd $(dirname $0); pwd)
 mkdir -p $SCRIPT_DIR/../generated/$PLAYLIST_NAME
@@ -27,7 +32,13 @@ for FILEPATH in $FILES; do
         name_en=$(echo $(trans -brief -no-warn -no-ansi ja:en "$name_format") | sed -e "s/\./ /g" | sed -e "s/^The *//" | sed -e "s/^ *//" | sed -e "s/ *$//" | sed -e "s/  / /" | sed -e "s/#//" )
         NAME=$name_en
     fi
-    echo "ffmpeg -ss $start_time -t $end_time -i \"$FILEPATH\" -r $rate \"$OUTPUT_DIR/$NAME%06d.jpg\""
-    ffmpeg -ss $start_time -t $end_time -i "$FILEPATH" -r $rate "$OUTPUT_DIR/$NAME%06d.jpg"
+    echo "ffmpeg -ss $start_time -t $length_time -i \"$FILEPATH\" -r $rate \"$OUTPUT_DIR/$NAME%06d.jpg\""
+    FFMPEG_RUNNING_THREADS="$(ps hf -opid,cmd -C "ffmpeg" | awk '$2 !~ /^[|\\]/ { ++n } END { print n }')"
+    echo "----- ffmpeg threads:$FFMPEG_RUNNING_THREADS -----"
+    while (($FFMPEG_RUNNING_THREADS >= $RUN_THREADS))
+    do
+    	FFMPEG_RUNNING_THREADS="$(ps hf -opid,cmd -C "ffmpeg" | awk '$2 !~ /^[|\\]/ { ++n } END { print n }')"
+    done
+    ffmpeg -ss $start_time -t $length_time -i "$FILEPATH" -r $rate "$OUTPUT_DIR/$NAME%06d.jpg" &
     echo "-----"
 done