[trans]在CentOS 5上安装FFMPEG

http://hi.baidu.com/lhabc/blog/item/6745898f6316c6f1503d9229.html

faac是用来压AAC音轨的，而faad2就是AAC音轨的解码器,liba52是进行AC3支持的
安装前准备编译的环境

yum install -y automake autoconf libtool gcc gcc-c++

1.下载需要的解码器
wget http://liba52.sourceforge.net/files/a52dec-0.7.4.tar.gz
wget http://downloads.sourceforge.net/faac/faad2-2.6.1.tar.gz
wget http://downloads.sourceforge.net/faac/faac-1.26.tar.gz
wget http://nchc.dl.sourceforge.net/sourceforge/lame/lame-3.97.tar.gz
wget http://www.tortall.net/projects/yasm/releases/yasm-0.7.0.tar.gz
wget ftp://ftp.videolan.org:21//pub/videolan/x264/snapshots/x264-snapshot-20090107-2245.tar.bz2
wget http://downloads.xvid.org/downloads/xvidcore-1.1.3.tar.gz
wget http://down1.chinaunix.net/distfiles/libdts-0.0.2.tar.gz

2.解压安装
解压
for i in *.tar.gz; do tar -xzvf "$i"; done
for i in *.tar.bz2; do tar -xjvf "$i"; done

安装的参数
a52dec: ./configure –enable-shared=PKGS && make && make install
faac & faad2: ./bootstrap && ./configure && make && make install
xvidcore: cd build/generic; ./configure && make && make install
libx264: ./configure –enable-mp4-output –enable-shared –enable-pthread && make && make install
lame & yasm: ./configure && make && make install

最后下载和安装ffmpeg
我是使用的svn同步比较新的，如果有时不能编译通过,可以考虑不使用最新的，不过要提示一下,就是连接这个网站，被我们国家的防火墙给kill掉了。需要各位自己想法子.

svn checkout svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg

编译参数
./configure –enable-gpl –enable-postproc –enable-nonfree –enable-postproc –enable-libfaad –enable-swscale –enable-avfilter –enable-pthreads –enable-libxvid –enable-libx264 –enable-libmp3lame –enable-libfaac –disable-ffserver –disable-ffplay

支持rm和rmvb

对rm和rmvb，只有ffmpeg是不行的，还需要下面的mplayer
svn checkout svn://svn.mplayerhq.hu/mplayer/trunk mplayer
wget http://www3.mplayerhq.hu/MPlayer/releases/codecs/essential-20071007.tar.bz2
wget http://www3.mplayerhq.hu/MPlayer/releases/codecs/all-20071007.tar.bz2
wget http://www.mplayerhq.hu/MPlayer/releases/codecs/essential-amd64-20071007.tar.bz2
for i in *.tar.bz2; do tar -xjvf "$i"; done
cp -rf essential-20071007/* /usr/local/lib/codecs
cp -rf all-20071007/* /usr/local/lib/codecs
cp -rf essential-amd64-20071007/* /usr/local/lib/codecs

./configure –prefix=/usr/local/mplayer –enable-gui –enable-freetype –codecsdir=/usr/local/lib/codes –win32codecsdir=/usr/local/lib/win32codcs

更新动态链接库

因为是编译器安装的，所以需要让系统可以找到动态链接库
#echo "/usr/local/lib" >> /etc/ld.so.conf
#echo "/usr/lib" >> /etc/ld.so.conf
#ldconfig

到这基本就安装完了

最基本的几个命令(一定要了解的)

显示支持的格式,不过好象加参数时，加其中的会有问题，看来参数和支持的格式是不一样的
$ ffmpeg -formats 

显示视频的相关信息,如时长,文件声音和视频格式之类的信息
ffmpeg -i abc.ts

查看可以加什么参数 
ffmpeg -h

mplayer获取影片信息
mplayer -identify movie-filename -nosound -vc dummy -vo null

使用ffmpeg从视频中抓图

ffmpeg -i 原视频文件路径 -y -f image2 -ss 8 -t 0.001 -s 图象大小(400×300) 图片存放路径

使用ffmpeg给视频转换成flv

ffmpeg -i 原视频文件路径 -o 目标文件路径 -of lavf -oac mp3lame -lameopts abr:br=56 -ovc lavc -lavcopts vcodec=flv:vbitrate=视频码流:mbd=2:mv0:trell:v4mv:cbp:last_pred=3:dia=4:cmp=6:vb_strategy=1 -vf scale=高:宽 -ofps 12 -srate 22050′)

ffmpeg 00:04:00 -t 00:08:00 -i -vcodec copy -acodec copy aaa.avi

FAQ
1.出现如下提示
-soname,libx264.so.65 -lm -lpthread -lgpac_static -s
/usr/bin/ld: cannot find -lgpac_static
collect2: ld returned 1 exit status
make: *** [libx264.so.65] Error 1

解决方法

yum install zlib-devel
wget http://internap.dl.sourceforge.net/sourceforge/gpac/gpac-0.4.5.tar.gz
wget http://internap.dl.sourceforge.net/sourceforge/gpac/gpac_extra_libs-0.4.5.tar.gz
tar -zxf gpac-0.4.5.tar.gz
tar -zxf gpac_extra_libs-0.4.5.tar.gz
cd gpac_extra_libs
cp -r * ../gpac/extra_lib
cd ../gpac
chmod +x configure
./configure
make lib
make apps
make install-lib
make install
cp bin/gcc/libgpac.so /usr/lib

注意,使用下面的参数出错
–enable-liba52 –enable-liba52bin
查看源码发现中包括了ac3

为了查找方便，把ffmpeg中的参数都列出来

参数 英文说明

-L	show license
-h	show help
-version	show version
-formats	显示可以使用的格式,编码,协议
-f	强行设置输出格式[fmt]
-i	输入文件名[filename]
-y	不询问直接覆盖输出文件
-map	set input stream mapping,file:stream[:syncfile:syncstream]
-map_meta_data	set meta data information of outfile from infile,outfile:infile
-t	set the recording time[duration]
-fs	set the limit file size［limit_size］
-ss	set the start time offset[time_off]
-itsoffset	set the input ts offset[time_off]
-title	视频文件标题[string]
-timestamp	set the timestamp[time]
-author	set the author[string]
-copyright	set the copyright[string]
-comment	set the comment[string]
-album	set the album[string]
-benchmark	add timings for benchmarking
-dump	dump each input packet
-hex	when dumping packets, also dump the payload
-re	read input at native frame rate
-loop_input	loop (current only works with images)
-loop_output	number of times to loop output in formats that support looping (0 loops forever)
-v	control amount of logging[verbose]
-target	specify target file type (”vcd”, “svcd”, “dvd”, “dv”, “dv50″, “pal-vcd”, “ntsc-svcd”, …)[type]
-threads	thread count[count]
-vsync	video sync method
-async	audio sync method
-vglobal	video global header storage type
-copyts	copy timestamps
-shortest	finish encoding within shortest input
-dts_delta_threshold	timestamp discontinuity delta threshold
以下是视频相关的命令
-vframes	按所提供的帧数对文件解码（例ffmpeg -i test5.flv -r 15 -s 384*288 -y -vframes 1 photos.flv）[num]
-aframes	set the number of audio frames to record[num]
-dframes	set the number of data frames to record[num]
-r	设置帧速率，每秒多少帧 (Hz value, fraction or abbreviation)[rate]
-s	设置视频的宽度和高度，格式为320×240，320*240,320:240都可以
-aspect	set aspect ratio (4:3, 16:9 or 1.3333, 1.7777)[aspect]
-pix_fmt	set pixel format[format]
-croptop	set top crop band size (in pixels)[size]
-cropbottom	“set bottom crop band size (in pixels)[size]
-cropleft	set left crop band size (in pixels)[size]
-cropright	set right crop band size (in pixels)[size]
-padtop	set top pad band size (in pixels)[size]
-padbottom	set bottom pad band size (in pixels)［size］
-padleft	set left pad band size (in pixels)［size］
-padright	set right pad band size (in pixels)[size]
-padcolor	set color of pad bands (Hex 000000 thru FFFFFF)[color]
-intra	use only intra frames
-vn	disable video
-vdt	discard threshold[n]
-qscale	use fixed video quantizer scale (VBR)[q]
-qdiff	max difference between the quantizer scale (VBR)[q]
-rc_eq	set rate control equation[equation]
-rc_override	rate control override for specific intervals[override]
-vcodec	force video codec (’copy’ to copy stream)［codec］
-me	set motion estimation method[method]
-me_threshold	motion estimaton threshold
-ps	set packet size in bits[size]
-strict	how strictly to follow the standards[strictness]
-sameq	use same video quality as source (implies VBR)
-pass	select the pass number (1 or 2)[n]
-passlogfile	select two pass log file name[filename]
-deinterlace	deinterlace pictures
-psnr	calculate PSNR of compressed frames
-vstats	dump video coding statistics to file
-vhook	insert video processing module[module]
-intra_matrix	specify intra matrix coeffs[matrix]
-inter_matrix	specify inter matrix coeffs[matrix]
-top	top=1/bottom=0/auto=-1 field first
-dc	intra_dc_precision[precision]
-vtag	force video tag/fourcc[fourcc/tag]
-newvideo	add a new video stream to the current output stream
-qphist	show QP histogram
以下是音频相关的命令
-ab	声音码流(in kbit/s)[bitrate]
-aq	声音品质(codec-specific)[quality]
-ar	声音的采样频率 (in Hz)[rate]
-ac	设置输出的声道数[channels]
-an	不输出声音
-acodec	设置输入声音的编码格式 (’copy’ to copy stream)[codec]
-atag	force audio tag/fourcc[fourcc/tag]
-vol	change audio volume (256=normal)[volume]
-newaudio	add a new audio stream to the current output stream
-alang	set the ISO 639 language code (3 letters) of the current audio stream[code]
以下是字幕相关的命令
-scodec	force subtitle codec (’copy’ to copy stream)[codec]
-newsubtitle	add a new subtitle stream to the current output stream
-slang	set the ISO 639 language code (3 letters) of the current subtitle stream[code]
以下是不常用的命令
-vd	set video grab device[device]
-vc	set video grab channel (DV1394 only)[channel]
-tvstd	set television standard (NTSC, PAL (SECAM))[standard]
-ad	set audio device[device]
-grab	request grabbing using[format]
-gd	set grab device[device]
-muxdelay	set the maximum demux-decode delay[sec]
-muxpreload	set the initial demux-decode delay[sec]
-absf
-vbsf
-default	generic catch all option

(ffmpeg参数说明)

http://hi.baidu.com/lhabc/blog/item/6745898f6316c6f1503d9229.html