Improve the compress video scripts

bin/compress-video-with-crf

@@ -23,22 +23,36 @@ else
     NORMAL=""
 fi
 
-use_gpu=$1
-use_crf=$2
-output_name="$4"
-start_time="$5"
-end_time="$6"
+use_gpu=0
 
-if [[ $use_gpu == "" || $use_crf == "" || $3 == "" || $output_name == "" || ($start_time != "" && $end_time == "") ]]; then
-    printf "${BOLD}${RED}Usage: $0 <use-gpu (1|0)> <crf value> <filename> <output name> <optional start time HH:MM:SS> <optional end time HH:MM:SS>\n\nIf you want to encode a range of CRF values then use -1 as the crf value.${NORMAL}\n"
+if [[ "$#" < 3 || "$#" > 6 ]]; then
+    printf "${BOLD}${RED}Usage: $0 <crf value> <filename> <output name> <optional: use-gpu (1|0), defaults to $use_gpu> <optional: start time HH:MM:SS> <optional: end time HH:MM:SS>\n\nIf you want to encode a range of CRF values then use -1 as the crf value.${NORMAL}\n"
     exit 1
 fi
 
+use_crf=$1
 
-filename=$(basename -- "$3")
+filename=$(basename -- "$2")
 extension="${filename##*.}"
 filename="${filename%.*}"
 
+output_name="$3"
+
+if [[ "$#" > 3 ]]; then
+    use_gpu=$4
+    if [[ "$#" > 4 ]]; then
+        start_time="$5"
+        if [[ "$#" > 5 ]]; then
+            end_time="$6"
+        fi
+    fi
+fi
+
+if [[ $use_gpu -ne 0 && $use_gpu -ne 1 ]]; then
+    printf "${BOLD}${RED}Invalid use_gpu value. Got $use_gpu, but expected either 0 or 1${NORMAL}\n"
+    exit 1
+fi
+
 function encode() {
     crf=$1
     output="${output_name}.$extension"