Bash - case statement always enters default - bash

Question

I am writing a Bash script to parse a CSV file (values separated by ; character) and extract some arguments. Depending on the current argument read from the file a specific string is appended to a variable. However, the case statement always enters the default state *) and I can't figure out why.
I have no problems reading the .csv file. Already did that and displayed the output of the arguments read from the file. Everything works perfectly. The problem is that the case statement is not processed as expected.
So, the problem is not reading the .csv file but the processing of the arguments in the case statement.
This is my code:
while IFS=";" read -r arg
do
case ${arg} in
"valueX")
var+="blabla"
;;
"valueY")
var+="blublu"
;;
*)
echo -e "Argument ${arg} not supported"
exit 1
;;
esac
done < filename
Assuming "valueX" is the current argument read from the file. Somehow the script always outputs:
Argument "valueX" not supported
Apparently, the argument (here: "valueX") read from the file is correct, but the script won't enter the corresponding state. Instead, it always enters the default state, no matter what value ${arg} holds.
[EDIT]
I thought it would be a good idea to ask the question more generally, but it turns out to be confusing. So here is the full bash script and .csv file:
Script:
#!/bin/bash
# style reset
STYLE_RESET='\e[0m'
# Red foreground color
FOREGROUND_RED='\e[31m'
# Green foreground color
FOREGROUND_GREEN='\e[32m'
# Blue foreground color
FOREGROUND_BLUE='\e[34m'
# Red background color
BACKGROUND_RED='\e[41m'
# Green background color
BACKGROUND_GREEN='\e[42m'
# Blue background color
BACKGROUND_BLUE='\e[44m'
SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" &> /dev/null && pwd )"
usage()
{
echo "ToDo"
exit 1
}
# --------------------------------------- #
# --- Checking Command Line Arguments --- #
# --------------------------------------- #
# Supported command line arguments:
# -h|--help
# -a|--address IP of SSH server for remote VMAF
# -u|--user User for SSH server login
# -d|--doe DoE worksheet exported as CSV UTF-8 file
PARAMS=""
while (( "$#" )); do
case "$1" in
-h|--help)
usage
shift
;;
-u|--user)
if [ -n "$2" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
SSH_USER=$2
shift 2
else
echo "Error: Argument for $1 is missing" >&2
exit 1
fi
;;
-a|--address)
if [ -n "$2" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
SSH_IP=$2
shift 2
else
echo "Error: Argument for $1 is missing" >&2
exit 1
fi
;;
-d|--doe)
if [ -n "$2" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
DOE_FILE=$2
shift 2
else
echo "Error: Argument for $1 is missing" >&2
exit 1
fi
;;
-*|--*=) # unsupported flags
echo "Error: Unsupported flag $1" >&2
exit 1
;;
*) # DEFAULT
PARAMS="${PARAMS} $1" # preserve positional arguments
shift
;;
esac
done
# set positional arguments in their proper place
eval set -- "${PARAMS}"
# ---------------------- #
# --- Processing DoE --- #
# ---------------------- #
echo -e "${BACKGROUND_BLUE}Processing DoE specified in file ${DOE_FILE}:${STYLE_RESET}"
echo -e "${BACKGROUND_BLUE}Configuring Video source for GStreamer pipeline...${STYLE_RESET}"
GSTPIPE_SRC="gst-launch-1.0 -e "
run=1
while IFS=";" read -r motion bitrate_in bitrate_out twopass iframe quantI quantP quantB mvbuffer cabac vbv
do
echo -e "\n\n${BACKGROUND_BLUE}Setting #${run}:${STYLE_RESET}"
echo -e "${BACKGROUND_BLUE}${motion} ${bitrate_in} ${bitrate_out} ${twopass} ${iframe} ${quantI} ${quantP} ${quantB} ${mvbuffer} ${cabac} ${vbv}${STYLE_RESET}"
echo -e "\n${BACKGROUND_BLUE}Generating GStreamer pipelines...${STYLE_RESET}"
case ${motion} in
"low")
GSTPIPE_SRC+="videotestsrc pattern=colors num-buffers=300 ! " # -> no motion content
case ${bitrate_in} in # -> bitrate of video source (width*height*framerate)
"low") # -> 640x480
GSTPIPE_SRC+="'video/x-raw, width=(int)640, height=(int)480, framerate=(fraction)30/1, format=(string)I420' "
width=640
height=480
fps=30
;;
"high") # -> 3840x2160
GSTPIPE_SRC+="'video/x-raw, width=(int)3840, height=(int)2160, framerate=(fraction)30/1, format=(string)I420' "
width=3840
height=2160
fps=30
;;
*)
echo -e "\n\n${BACKGROUND_RED}Input bitrate ${bitrate_in} not supported${STYLE_RESET}"
echo -e "Use low, or high instead"
exit 1
;;
esac
;;
"high")
GSTPIPE_SRC+="filesrc location=${SCRIPT_DIR}/extensive.mp4 " # -> high motion content
case ${bitrate_in} in # -> bitrate of video source (width*height*framerate)
"low") # -> 640x480
GSTPIPE_SRC+="blocksize=460800 ! " # blocksize=width*height*bytesPerPixel (I420->12bit->bytesPerPixel=1.5)
GSTPIPE_SRC+="'video/x-raw, width=(int)640, height=(int)480, framerate=(fraction)30/1, format=(string)I420' "
width=640
height=480
fps=30
;;
"high") # -> 3840x2160
GSTPIPE_SRC+="blocksize=12441600 ! " # blocksize=width*height*bytesPerPixel (I420->12bit->bytesPerPixel=1.5)
GSTPIPE_SRC+="'video/x-raw, width=(int)3840, height=(int)2160, framerate=(fraction)30/1, format=(string)I420' "
width=3840
height=2160
fps=30
;;
*)
echo -e "\n\n${BACKGROUND_RED}Input bitrate ${bitrate_in} not supported${STYLE_RESET}"
echo -e "Use low, or high instead"
exit 1
;;
esac
;;
*)
echo -e "${BACKGROUND_RED}Argument ${motion} for DoE factor 'motion' not supported${STYLE_RESET}"
echo -e "Use low, or high instead"
exit 1
;;
esac
GSTPIPE_ENC=$GSTPIPE_SRC
GSTPIPE_REF=$GSTPIPE_SRC
GSTPIPE_REF+="! y4menc ! filesink location=${SCRIPT_DIR}/reference${fps}fps_run${run}.y4m"
GSTPIPE_ENC+="! nvvidconv ! 'video/x-raw(memory:NVMM)' ! nvv4l2h264enc "
GSTPIPE_ENC+="bitrate=${bitrate_out} EnableTwopassCBR=${twopass} "
case ${iframe} in
"low")
GSTPIPE_ENC+="iframeinterval=20 SliceIntraRefreshInterval=10 "
;;
"high")
GSTPIPE_ENC+="iframeinterval=120 SliceIntraRefreshInterval=60 "
;;
*)
echo -e "${BACKGROUND_RED}Argument ${motion} for DoE factor iframe is not supported${STYLE_RESET}"
echo -e "Use low, or high instead"
exit 1
;;
esac
# The range of B frames does not take effect if the number of B frames is 0. (https://docs.nvidia.com/jetson/l4t/index.html#page/Tegra%20Linux%20Driver%20Package%20Development%20Guide/accelerated_gstreamer.html#wwpID0E0YX0HA)
GSTPIPE_ENC+="quant-i-frames=${quantI} quant-p-frames=${quantP} quant-b-frames=${quantB} num-b-frames=1 EnableMVBufferMeta=${mvbuffer} cabac-entropy-coding=${cabac} "
GSTPIPE_ENC+="! nvv4l2decoder ! nvvidconv ! 'video/x-raw' ! y4menc ! filesink location=${SCRIPT_DIR}/distorted${fps}fps_run${run}.y4m"
echo -e "${BACKGROUND_BLUE}Distorted Video:${STYLE_RESET}"
echo -e "${FOREGROUND_BLUE}${GSTPIPE_ENC}${STYLE_RESET}"
echo -e "${BACKGROUND_BLUE}Reference Video:${STYLE_RESET}"
echo -e "${FOREGROUND_BLUE}${GSTPIPE_REF}${STYLE_RESET}"
# --- Launching GStreamer pipelines (surpress detailed output) --- #
echo -e "${BACKGROUND_BLUE}Launching GStreamer pipeline for encoded video (distorted):${STYLE_RESET}"
eval "${GSTPIPE_ENC[#]}" #> /dev/null
echo -e "${BACKGROUND_BLUE}Launching GStreamer pipeline for uncompressed video (reference):${STYLE_RESET}"
eval "${GSTPIPE_REF[#]}" #> /dev/null
# --- Create and Check Remote Directories --- #
echo -e "\n${BACKGROUND_BLUE}Video transfer to remote machine:${STYLE_RESET}"
SSH_DIR_ADD="v4l2h264/motion_${motion}/bitrate_${bitrate_in}/"
SSH_DIR="/home/${SSH_USER}/metrics/${SSH_DIR_ADD}" # Create variable holding path of directory for both:
# 1.) reference.y4m and distorted.y4m videos
# 2.) remote VMAF
ssh ${SSH_USER}#${SSH_IP} "test -d ${SSH_DIR}" < /dev/null # see https://stackoverflow.com/questions/9393038/ssh-breaks-out-of-while-loop-in-bash
if [ $? -ne 0 ]; then # Directory does not exist
echo -e "${BACKGROUND_BLUE}Creating remote directory for run #${run}: ${SSH_DIR}...${STYLE_RESET}"
ssh ${SSH_USER}#${SSH_IP} "mkdir -p ${SSH_DIR}" < /dev/null # see https://stackoverflow.com/questions/9393038/ssh-breaks-out-of-while-loop-in-bash
else # Directory already exists
echo -e "${BACKGROUND_BLUE}Remote directory ${SSH_DIR} already exists${STYLE_RESET}"
fi
# --- Transfer Video Files --- #
echo -e "${BACKGROUND_BLUE}Transfering reference and distorted videos of run #${run}:${STYLE_RESET}"
scp ${SCRIPT_DIR}/distorted${fps}fps_run${run}.y4m ${SSH_USER}#${SSH_IP}:${SSH_DIR} < /dev/null # see https://stackoverflow.com/questions/9393038/ssh-breaks-out-of-while-loop-in-bash
scp ${SCRIPT_DIR}/reference${fps}fps_run${run}.y4m ${SSH_USER}#${SSH_IP}:${SSH_DIR} < /dev/null # see https://stackoverflow.com/questions/9393038/ssh-breaks-out-of-while-loop-in-bash
# --- Run VMAF on Remote Machine --- #
echo -e "\n${BACKGROUND_BLUE}Running VMAF metric for DoE run #${run} on remote machine...${STYLE_RESET}"
ssh ${SSH_USER}#${SSH_IP} "vmaf -r ${SSH_DIR}/reference${fps}fps_run${run}.y4m -d ${SSH_DIR}/distorted${fps}fps_run${run}.y4m -w ${width} -h ${height} -p 420 -b 12 -o ${SSH_DIR}/log${fps}fps_run${run}.xml --threads 8" < /dev/null # see https://stackoverflow.com/questions/9393038/ssh-breaks-out-of-while-loop-in-bash
echo -e "${BACKGROUND_BLUE}VMAF metric for DoE run #${run} finished.${STYLE_RESET}"
# --- Remove Videos on Remote Machine (Laptop) --- #
echo -e "\n${BACKGROUND_BLUE}Removing videos from remote machine${STYLE_RESET}"
ssh ${SSH_USER}#${SSH_IP} "rm ${SSH_DIR}/distorted${fps}fps_run${run}.y4m ${SSH_DIR}/reference${fps}fps_run${run}.y4m" < /dev/null # see https://stackoverflow.com/questions/9393038/ssh-breaks-out-of-while-loop-in-bash
# --- Remove videos on local machine (SPU) --- #
echo -e "\n${BACKGROUND_BLUE}Removing videos from local machine${STYLE_RESET}"
rm distorted${fps}fps_run${run}.y4m reference${fps}fps_run${run}.y4m
((run++))
done < <(cut -d ";" -f5,6,7,8,9,10,11,12,13,14,15,16 ${DOE_FILE} | tail -n +2) # read from the second line of the file (no header) and only read the columns specified with -f
((run--))
exit 0
.csv file:
"StdOrder";"RunOrder";"CenterPt";"Blocks";"motion";"bitrate_in";"bitrate_out";"twopass";"iframe";"quantI";"quantP";"quantB";"mvbuffer";"cabac"
1;1;1;1;"low";"low";200000;"false";"low";0;0;0;"true";"true"
6;2;1;1;"high";"low";80000000;"false";"low";51;0;51;"true";"false"
8;3;1;1;"high";"high";80000000;"false";"high";0;0;0;"false";"true"
2;4;1;1;"high";"low";200000;"false";"high";0;51;51;"false";"false"
3;5;1;1;"low";"high";200000;"false";"high";51;0;51;"false";"false"
7;6;1;1;"low";"high";80000000;"false";"low";0;51;51;"true";"false"
10;7;1;1;"high";"low";200000;"true";"high";51;0;0;"true";"false"
9;8;1;1;"low";"low";200000;"true";"low";51;51;51;"false";"true"
4;9;1;1;"high";"high";200000;"false";"low";51;51;0;"true";"true"
13;10;1;1;"low";"low";80000000;"true";"high";0;0;51;"true";"true"
5;11;1;1;"low";"low";80000000;"false";"high";51;51;0;"false";"true"
12;12;1;1;"high";"high";200000;"true";"low";0;0;51;"false";"true"
15;13;1;1;"low";"high";80000000;"true";"low";51;0;0;"false";"false"
14;14;1;1;"high";"low";80000000;"true";"low";0;51;0;"false";"false"
16;15;1;1;"high";"high";80000000;"true";"high";51;51;51;"true";"true"
11;16;1;1;"low";"high";200000;"true";"high";0;51;0;"true";"false"

Answer 1

Apparently, the argument (here: "valueX") read from the file is correct
Since you consider the quotes being part of the argument to be correct, in order to match them with a case pattern, you have to escape the pattern quotes:
case ${arg} in
\"valueX\")
Interestingly, this appears to be a Bash (documentation) error, as that says only:
Each pattern undergoes tilde expansion, parameter expansion, command substitution, and arithmetic expansion.
It doesn't tell that the pattern undergoes quote removal.

Answer 2

None of your sample data contains valueX, but assuming you were looking for e.g. "high" in the fifth field, you need to ask the shell to split into at least six fields;
while IFS=";" read -r _first _second _third _fourth arg _rest
do
case ${arg} in
'"high"')
var+="blabla"
;;
'"low"')
var+="blublu"
;;
*)
echo -e "Argument ${arg} not supported"
exit 1
;;
esac
done < filename
Probably a better solution here is to use Awk, though.
awk -F ';' '$5 !~ /"(high|low)"/ { print "Argument " $5 " is not supported" }' filename
Without the rest of your script, it's hard to tell in which direction to continue this; very often, if you are using Awk anyway, it makes sense to implement the rest of the logic in Awk, too.