linux中使用ffmpeg 无损剪切/拼接视频程序
发布:smiling 来源: PHP粉丝网 添加日期:2015-04-28 15:14:30 浏览: 评论:0
ffmpeg是一款视频处理工具了,我们可以在系统中安装之后利用ffmpeg命令进行视频的处理了,下面就一起来看看吧.
剪切/拼接视频文件是一种常见需求,在线视频网站现在往往将一个视频文件分割成 n 段,以减少流量消耗,使用 DownloadHelper/DownThemAll 这类工具下载下来的往往就是分割后的文件,能实现剪切/拼接视频文件的工具多种多样,但往往都需要进行视频重编码(transcoding),这就不可避免的带来了视频质量上的损耗,更不用提那长的令人发指的转换时间了…
其实借助 ffmpeg 我们就可以在不进行视频重编码的情况下完成此类任务.
剪切代码如下:
- ffmpeg -i input.mp4 -ss **START_TIME** -t **STOP_TIME** -acodec copy -vcodec copy output.mp4
其中 START_TIME/STOP_TIME 的格式可以写成两种格式:
以秒为单位计数: 80
时:分:秒: 00:01:20
拼接:
拼接的情况稍微复杂些,我们需要将需要拼接的视频文件按以下格式保存在一个列表 list.txt 中,代码如下:
- file '/path/to/file1'
- file '/path/to/file2'
- file '/path/to/file3'
相应的命令为如下代码:
ffmpeg -f concat -i **list.txt** -c copy output.mp4
由于不需要重编码,这两条命令几乎是即时完成的,方便起见,我写了一个脚本来简化操作,放在 github 上,请自取,代码如下:
- #!/bin/bash
- #cut/join videos using ffmpeg without quality loss
- if [ -z $1 ] || [ -z $2 ]; then
- echo "Usage:$0 c[ut] seconds <File>"
- echo " eg. $0 c 10 80 example.mp4"
- echo " eg. $0 c 00:00:10 00:01:20 example.mp4"
- echo "Usage:$0 j[oin] <FileType>"
- echo " eg. $0 j avi"
- exit
- fi
- case "$1" in
- c)
- echo "cuttig video..."
- fileName=$(echo $4 | cut -f 1 -d '.')
- fileType=$(echo $4 | cut -f 2 -d '.')
- ffmpeg -i $4 -ss $2 -t $3 -acodec copy -vcodec copy $fileName-$2-$3.$fileType
- ;;
- j)
- echo "joinning videos..."
- rm temp_list.txt
- for f in ./*.$2; do echo "file '$f'" >> temp_list.txt; done
- printf "file '%s'\n" ./*.$2 > temp_list.txt
- ffmpeg -f concat -i temp_list.txt -c copy output.$2
- rm temp_list.txt //phpfensi.com
- ;;
- *)
- echo "wrong arguments"
- ;;
- esac
- exit
以上拼接操作生效的前提是,所有视频文件的格式编码相同,如果需要拼接不同格式的视频文件可以借助以下脚本,代码如下:
- # change this to what you need !!!
- EXTRA_OPTIONS='-vcodec libx264 -crf 23 -preset medium -acodec aac -strict experimental -ac 2 -ar 44100 -ab 128k'
- ################################################################################
- #
- # NO NEED TO TOUCH ANYTHING AFTER THIS LINE!
- #
- ################################################################################
- # the version of the script
- VERSION=1.3
- # location of temp folder
- TMP=/tmp
- ################################################################################
- echo "MultiMedia Concat Script v$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)
- # $inputs - all the inputs, except the first input, because 1st input is
- # handled separately
- ################################################################################
- first=${@:1:1}
- last=${@:$#:1}
- len=$(($#-2))
- inputs=${@:2:$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 -f u16le -acodec pcm_s16le -ac 2 -ar 44100 -i $TMP/mcs_a_all \
- -f yuv4mpegpipe -vcodec rawvideo -i $TMP/mcs_v_all \
- $EXTRA_OPTIONS \
- $last
- ################################################################################
- # remove all fifos
- ################################################################################
- rm -f $TMP/mcs_*
Tags: ffmpeg linux剪切
推荐文章
热门文章
最新评论文章
- 写给考虑创业的年轻程序员(10)
- PHP新手上路(一)(7)
- 惹恼程序员的十件事(5)
- PHP邮件发送例子,已测试成功(5)
- 致初学者:PHP比ASP优秀的七个理由(4)
- PHP会被淘汰吗?(4)
- PHP新手上路(四)(4)
- 如何去学习PHP?(2)
- 简单入门级php分页代码(2)
- php中邮箱email 电话等格式的验证(2)