Bash - case语句总是进入default
Bash - case statement always enters default
我正在编写一个 Bash 脚本来解析 CSV 文件（值由 ; 字符分隔）并提取一些参数。根据从文件中读取的当前参数，将特定字符串附加到变量。但是，case语句总是进入默认状态*)，想不通为什么。
我读取 .csv 文件没有问题。已经这样做并显示了从文件中读取的参数的输出。一切都很完美。问题是case语句没有按预期处理。
因此，问题不在于读取 .csv 文件，而在于处理 case 语句中的参数。
这是我的代码：
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
假设“valueX”是从文件中读取的当前参数。脚本总是以某种方式输出：
Argument "valueX" not supported
显然，从文件中读取的参数（此处为："valueX"）是正确的，但脚本不会进入相应的状态。相反，它总是进入默认状态，无论 ${arg} 保持什么值。
[编辑]
我认为更笼统地问这个问题是个好主意，但结果却令人困惑。所以这是完整的 bash 脚本和 .csv 文件：
脚本：
#!/bin/bash
# style reset
STYLE_RESET='\e[0m'
# Red foreground color
FOREGROUND_RED='\e[31m'
# Green foreground color
FOREGROUND_GREEN='\e[32m'
# Blue foreground color
FOREGROUND_BLUE='\e[34m'
# Red background color
BACKGROUND_RED='\e[41m'
# Green background color
BACKGROUND_GREEN='\e[42m'
# Blue background color
BACKGROUND_BLUE='\e[44m'
SCRIPT_DIR="$( 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 "" in
-h|--help)
usage
shift
;;
-u|--user)
if [ -n "" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
SSH_USER=
shift 2
else
echo "Error: Argument for is missing" >&2
exit 1
fi
;;
-a|--address)
if [ -n "" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
SSH_IP=
shift 2
else
echo "Error: Argument for is missing" >&2
exit 1
fi
;;
-d|--doe)
if [ -n "" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
DOE_FILE=
shift 2
else
echo "Error: Argument for is missing" >&2
exit 1
fi
;;
-*|--*=) # unsupported flags
echo "Error: Unsupported flag " >&2
exit 1
;;
*) # DEFAULT
PARAMS="${PARAMS} " # 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
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 ${SSH_DIR}" < /dev/null # see
else # Directory already exists
echo -e "${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
scp ${SCRIPT_DIR}/reference${fps}fps_run${run}.y4m ${SSH_USER}@${SSH_IP}:${SSH_DIR} < /dev/null # see
# --- Run VMAF on Remote Machine --- #
echo -e "\n${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${run}.xml --threads 8" < /dev/null # see
echo -e "${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${run}.y4m" < /dev/null # see
# --- Remove videos on local machine (SPU) --- #
echo -e "\n${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 文件：
"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"
Apparently, the argument (here: "valueX") read from the file is correct
由于您认为引号是参数的一部分是正确的，为了将它们与 case 模式匹配，您必须转义模式引号：
case ${arg} in
\"valueX\")
有趣的是，这似乎是一个 Bash (documentation) 错误，正如上面所说的那样：
Each pattern undergoes tilde expansion, parameter expansion, command substitution, and arithmetic expansion.
它并没有说明该模式经历了引用删除。
None 的示例数据包含 valueX，但假设您正在寻找例如"high"在第五个字段中，需要要求shell至少拆分成六个字段；
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
不过，这里可能更好的解决方案是使用 Awk。
awk -F ';' ' !~ /"(high|low)"/ { print "Argument " " is not supported" }' filename
如果没有你的脚本的其余部分，很难判断该往哪个方向继续；通常，如果您无论如何都在使用 Awk，那么在 Awk 中实现其余逻辑也是有意义的。
我正在编写一个 Bash 脚本来解析 CSV 文件（值由 ; 字符分隔）并提取一些参数。根据从文件中读取的当前参数，将特定字符串附加到变量。但是，case语句总是进入默认状态*)，想不通为什么。
我读取 .csv 文件没有问题。已经这样做并显示了从文件中读取的参数的输出。一切都很完美。问题是case语句没有按预期处理。
因此，问题不在于读取 .csv 文件，而在于处理 case 语句中的参数。
这是我的代码：
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
假设“valueX”是从文件中读取的当前参数。脚本总是以某种方式输出：
Argument "valueX" not supported
显然，从文件中读取的参数（此处为："valueX"）是正确的，但脚本不会进入相应的状态。相反，它总是进入默认状态，无论 ${arg} 保持什么值。
[编辑] 我认为更笼统地问这个问题是个好主意，但结果却令人困惑。所以这是完整的 bash 脚本和 .csv 文件：
脚本：
#!/bin/bash
# style reset
STYLE_RESET='\e[0m'
# Red foreground color
FOREGROUND_RED='\e[31m'
# Green foreground color
FOREGROUND_GREEN='\e[32m'
# Blue foreground color
FOREGROUND_BLUE='\e[34m'
# Red background color
BACKGROUND_RED='\e[41m'
# Green background color
BACKGROUND_GREEN='\e[42m'
# Blue background color
BACKGROUND_BLUE='\e[44m'
SCRIPT_DIR="$( 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 "" in
-h|--help)
usage
shift
;;
-u|--user)
if [ -n "" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
SSH_USER=
shift 2
else
echo "Error: Argument for is missing" >&2
exit 1
fi
;;
-a|--address)
if [ -n "" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
SSH_IP=
shift 2
else
echo "Error: Argument for is missing" >&2
exit 1
fi
;;
-d|--doe)
if [ -n "" ] && [ ${2:0:1} != "-" ]; then # Check length of argument and first character of argument != '-'
DOE_FILE=
shift 2
else
echo "Error: Argument for is missing" >&2
exit 1
fi
;;
-*|--*=) # unsupported flags
echo "Error: Unsupported flag " >&2
exit 1
;;
*) # DEFAULT
PARAMS="${PARAMS} " # 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
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 ${SSH_DIR}" < /dev/null # see
else # Directory already exists
echo -e "${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
scp ${SCRIPT_DIR}/reference${fps}fps_run${run}.y4m ${SSH_USER}@${SSH_IP}:${SSH_DIR} < /dev/null # see
# --- Run VMAF on Remote Machine --- #
echo -e "\n${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${run}.xml --threads 8" < /dev/null # see
echo -e "${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${run}.y4m" < /dev/null # see
# --- Remove videos on local machine (SPU) --- #
echo -e "\n${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 文件：
"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"
Apparently, the argument (here: "valueX") read from the file is correct
由于您认为引号是参数的一部分是正确的，为了将它们与 case 模式匹配，您必须转义模式引号：
case ${arg} in
\"valueX\")
有趣的是，这似乎是一个 Bash (documentation) 错误，正如上面所说的那样：
Each pattern undergoes tilde expansion, parameter expansion, command substitution, and arithmetic expansion.
它并没有说明该模式经历了引用删除。
None 的示例数据包含 valueX，但假设您正在寻找例如"high"在第五个字段中，需要要求shell至少拆分成六个字段；
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
不过，这里可能更好的解决方案是使用 Awk。
awk -F ';' ' !~ /"(high|low)"/ { print "Argument " " is not supported" }' filename
如果没有你的脚本的其余部分，很难判断该往哪个方向继续；通常，如果您无论如何都在使用 Awk，那么在 Awk 中实现其余逻辑也是有意义的。