我想使用 Ghostscript 压缩给定目录及其子目录中的所有 pdf 文件。
我被困find
在按文件名(包括空格)循环内使用该命令。
这是我想要的一些示例代码:
pdffiles=$(find /path/to/directory -type f -name *.pdf)
for file in pdffiles; do
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dBATCH -dQUIET -sOutputFile=new_$file $file;
rm $file;
mv new_$file $file;
done;
知道如何解决空间问题吗?有一个更好的方法吗?
答案1
单行脚本也是一种选择:
find -type f -name "*.pdf" -exec bash -c 'gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dBATCH -dQUIET -sOutputFile="new.pdf" "{}"; rm "{}"; mv "new.pdf" "{}";' {} \;
答案2
我根据您的精彩回复重构了我的脚本,并且运行得很好:)
这是经过重构、改进的代码,包含日志记录、参数和其他一些内容。我始终乐于改进我的代码。
#!/bin/bash
## Script to compress PDF Files using Ghostscript incl. subdirs
## Copyright (C) 2016 Maximilian Fries - All Rights Reserved
## Contact: [email protected]
## Last revised 2016-07-29
# Usage
# ./pdf-compress.sh [screen|ebook|prepress|default] [verbose]
# Variables and preparation
{
count=0
success=0
successlog=./success.tmp
gain=0
gainlog=./gain.tmp
pdfs=$(find ./ -type f -name "*.pdf")
total=$(echo "$pdfs" | wc -l)
log=./log
verbose="-dQUIET"
mode="prepress"
echo "0" | tee $successlog $gainlog > /dev/null
}
# Are there any PDFs?
if [ "$total" -gt 0 ]; then
#Parameter Handling & Logging
{
echo "-- Debugging for Log START --"
echo "Number of Parameters: $#"
echo "Parameters are: $*"
echo "-- Debugging for Log END --"
} >> $log
# Only compression-mode set
if [ $# -eq 1 ]; then
mode="$1"
fi
# Also Verbose Level Set
if [ $# -eq 2 ]; then
mode="$1"
verbose=""
fi
echo "$pdfs" | while read -r file
do
((count++))
echo "Processing File #$count of $total Files" | tee -a $log
echo "Current File: $file "| tee -a $log
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS="/$mode" -dNOPAUSE \
-dBATCH $verbose -sOutputFile="$file-new" "$file" | tee -a $log
sizeold=$(wc -c "$file" | cut -d' ' -f1)
sizenew=$(wc -c "$file-new" | cut -d' ' -f1)
difference=$((sizenew-sizeold))
# Check if new filesize is smaller
if [ $difference -lt 0 ]
then
rm "$file"
mv "$file-new" "$file"
printf "Compression was successful. New File is %'.f Bytes smaller\n" \
$((-difference)) | tee -a $log
((success++))
echo $success > $successlog
((gain-=difference))
echo $gain > $gainlog
else
rm "$file-new"
echo "Compression was not necessary" | tee -a $log
fi
done
# Print Statistics
printf "Successfully compressed %'.f of %'.f files\n" $(cat $successlog) $total | tee -a $log
printf "Saved a total of %'.f Bytes\n" $(cat $gainlog) | tee -a $log
rm $successlog $gainlog
else
echo "No PDF File in Directory"
fi
答案3
你的循环最好写成
find ... | while read -r file
但是您需要确保在循环内引用文件名。所以我们最终得到
find /path/to/directory -type f -name *.pdf | while read -r file
do
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/screen -dNOPAUSE -dBATCH -dQUIET -sOutputFile="new_$file" "$file"
rm "$file"
mv "new_$file" "$file"
done
(另请注意,所有这些;
都不需要)。
现在这个循环有潜在的文件所有权/权限问题,但这是另一个问题:-)