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我有以下 bash 脚本(取自 FFmpeg)
#!/bin/bash
################################################################################
#
# Script name: MultiMedia Concat Script (mmcat)
# Author: burek ([email protected])
# License: GNU/GPL, see http://www.gnu.org/copyleft/gpl.html
# Date: 2012-07-14
#
# This script concatenates (joins, merges) several audio/video inputs into one
# final output (just like as if all the inputs were played in a playlist, one
# after another).
#
# All input files must have at least one audio and at least one video stream.
# If not, you can easily add audio silence, using FFmpeg. Just search the
# internet for "ffmpeg add silence".
#
# The script makes use of FFmpeg tool (www.ffmpeg.org) and is free for use under
# the GPL license. The inspiration for this script came from this FAQ item:
# http://ffmpeg.org/faq.html#How-can-I-join-video-files_003f
#
# If you find any bugs, please send me an e-mail so I can fix it.
#
################################################################################
#
# General syntax: mmcat <input1> <input2> <input3> ... <output>
#
# For example: mmcat file1.flv file2.flv output.flv
# would create "output.flv" out of "file1.flv" and "file2.flv".
#
################################################################################
# change this to what you need !!!
EXTRA_OPTIONS=${@:2:1}
################################################################################
#
# NO NEED TO TOUCH ANYTHING AFTER THIS LINE!
#
################################################################################
# the version of the script
VERSION=1.3
# location of temp folder
TMP=${@:1:1}
rm -rf $TMP
mkdir $TMP
################################################################################
echo "MultiMedia Concat Script v$VERSION (mmcat) - A script to concatenate multiple multimedia files."
echo "Based on FFmpeg - www.ffmpeg.org"
echo "Don't forget to edit this script and change EXTRA_OPTIONS"
echo ""
################################################################################
# syntax check (has to have at least 3 params: infile1, infile2, outfile
################################################################################
if [ -z $3 ]; then
echo "Syntax: $0 <input1> <input2> <input3> ... <output>"
exit 1
fi
################################################################################
# get all the command line parameters, except for the last one, which is output
################################################################################
# $first - first parameter
# $last - last parameter (output file)
# $inputs - all the inputs, except the first input, because 1st input is
# handled separately
################################################################################
first=${@:3:1}
last=${@:$#:1}
len=$(($#-4))
inputs=${@:4:$len}
# remove all previous tmp fifos (if exist)
rm -f $TMP/mcs_*
################################################################################
# decode first input differently, because the video header does not have to be
# kept for each video input, only the header from the first video is needed
################################################################################
mkfifo $TMP/mcs_a1 $TMP/mcs_v1
ffmpeg -y -i "$first" -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 $TMP/mcs_a1 2>/dev/null </dev/null &
ffmpeg -y -i "$first" -an -f yuv4mpegpipe -vcodec rawvideo $TMP/mcs_v1 2>/dev/null </dev/null &
# if you need to log the output of decoding processes (usually not necessary)
# then replace the "2>/dev/null" in 2 lines above with your log file names, like this:
#ffmpeg -y -i "$first" -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 $TMP/mcs_a1 2>$TMP/log.a.1 </dev/null &
#ffmpeg -y -i "$first" -an -f yuv4mpegpipe -vcodec rawvideo $TMP/mcs_v1 2>$TMP/log.v.1 </dev/null &
################################################################################
# decode all the other inputs, remove first line of video (header) with tail
# $all_a and $all_v are lists of all a/v fifos, to be used by "cat" later on
################################################################################
all_a=$TMP/mcs_a1
all_v=$TMP/mcs_v1
i=2
for f in $inputs
do
mkfifo $TMP/mcs_a$i $TMP/mcs_v$i
ffmpeg -y -i "$f" -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 $TMP/mcs_a$i 2>/dev/null </dev/null &
{ ffmpeg -y -i "$f" -an -f yuv4mpegpipe -vcodec rawvideo - 2>/dev/null </dev/null | tail -n +2 > $TMP/mcs_v$i ; } &
# if you need to log the output of decoding processes (usually not necessary)
# then replace the "2>/dev/null" in 2 lines above with your log file names, like this:
#ffmpeg -y -i "$f" -vn -f u16le -acodec pcm_s16le -ac 2 -ar 44100 $TMP/mcs_a$i 2>$TMP/log.a.$i </dev/null &
#{ ffmpeg -y -i $f -an -f yuv4mpegpipe -vcodec rawvideo - 2>$TMP/log.v.$i </dev/null | tail -n +2 > $TMP/mcs_v$i ; } &
all_a="$all_a $TMP/mcs_a$i"
all_v="$all_v $TMP/mcs_v$i"
let i++
done
################################################################################
# concatenate all raw audio/video inputs into one audio/video
################################################################################
mkfifo $TMP/mcs_a_all
mkfifo $TMP/mcs_v_all
cat $all_a > $TMP/mcs_a_all &
cat $all_v > $TMP/mcs_v_all &
################################################################################
# finally, encode the raw concatenated audio/video into something useful
################################################################################
ffmpeg -y -f u16le -acodec pcm_s16le -ac 2 -ar 44100 -i $TMP/mcs_a_all \
-y -f yuv4mpegpipe -vcodec rawvideo -i $TMP/mcs_v_all \
$EXTRA_OPTIONS \
$last
################################################################################
# remove all fifos
################################################################################
rm -f $TMP/mcs_*
上面的脚本接受这样的参数
bash script.sh tmp_folder video1 video2 video3 video4 ... output
其工作正常,但是,当参数有空格时,它无法正确读取参数。例如,如果我有一个视频位于“/tmp/my video.avi”它无法正确阅读并认为其不同的论点。
问题出在这几行
first=${@:3:1}
last=${@:$#:1}
len=$(($#-4))
inputs=${@:4:$len}
请注意,您将在脚本中看到 video2、video3 和 video4 与 video1 分开处理。
答案1
我猜问题(或者如果有很多的话,就是一个)问题是这一行:
inputs=${@:4:$len}
如果$len
大于 1,则将数组切片转换为字符串,并出现分词问题。
可能的解决方案
如果上面的行改为
inputs=("${@:4:$len}")
和这个
for f in $inputs
到
for f in "${inputs[@]}"
答案2
您必须在脚本中的任何工作文件之前设置以下代码:
SAVEIFS=$IFS
IFS=$(echo -en "\n\b")
然后当你想退出脚本时,你必须这样做:
$IFS=$SAVEIFS