austenconstable.com » Linux http://www.austenconstable.com a year in the merde Thu, 15 Oct 2009 16:19:43 +0000 en hourly 1 http://wordpress.org/?v=3.2.1 HOWTO: Recursively delete matching files on the Linux command line http://www.austenconstable.com/2008/10/08/recursively-delete-matching-files-on-the-linux-command-line/ http://www.austenconstable.com/2008/10/08/recursively-delete-matching-files-on-the-linux-command-line/#comments Wed, 08 Oct 2008 09:18:11 +0000 Austen http://www.austenconstable.com/?p=67 Continue reading →]]> An easy way to recursively delete files matching a particular pattern is to use this one liner:

find | grep "search" | perl -nle unlink

UPDATE – Another handy one liner to recursively delete directories is:

rm -rf `find . -type d -name .svn`

Obviously replacing “.svn” with whatever your directories are called.

]]> http://www.austenconstable.com/2008/10/08/recursively-delete-matching-files-on-the-linux-command-line/feed/ 0 HOWTO: Recursive search and replace on the Linux command line http://www.austenconstable.com/2008/09/02/recursive-search-and-replace-on-the-linux-command-line/ http://www.austenconstable.com/2008/09/02/recursive-search-and-replace-on-the-linux-command-line/#comments Tue, 02 Sep 2008 15:35:16 +0000 Austen http://www.austenconstable.com/?p=58 Continue reading →]]> The ‘traditional’ way to search and replace on the command line was to use some combination of grep/find/perl/sed etc. Which offers great flexibility but at the end of the day can turn into a right pain in order to complete a simple task. Turns out only to be a pain in the ass if you don’t know or can’t remember the correct syntax!

Recently I stumbled across rpl. (http://freshmeat.net/projects/rpl/) It’s a nice little text replacement utility which is as simple as:

rpl -R search replace *

Although rpl is easy, the other alternatives are hardly difficult. (At least once you know them)

For non-recursive search and replace try: Perl or sed. (At some point I’m sure I’ll get around to finding recursive Perl and sed alternatives.)

]]> http://www.austenconstable.com/2008/09/02/recursive-search-and-replace-on-the-linux-command-line/feed/ 0 HOWTO: Compiling the latest FFmpeg & x264 on CentOS 4 http://www.austenconstable.com/2008/08/06/howto-compiling-the-latest-ffmpeg-x264-on-centos-4/ http://www.austenconstable.com/2008/08/06/howto-compiling-the-latest-ffmpeg-x264-on-centos-4/#comments Wed, 06 Aug 2008 10:13:50 +0000 Austen http://www.austenconstable.com/?p=44 Continue reading →]]> Intoduction

FFmpeg is a superb video processing tool used to encode and transcode video files. In this particular project I needed to build “youtube” style video upload which would transcode into FLV, specifically catering for video files from the Nokia N95.

I spent quite a long time messing about with the stock version of ffmpeg on CentOS 4/Ubuntu trying to make it work, but it turned out not to be new enough/have all the right support compiled in.

This howto was written because I couldn’t find anything that fitted the bill for CentOS/RHEL (And being a Ubuntu man, found it a pain to get it compiled and working under CentOS). It’s based on the excellent tutorial by FakeOutdoorsman over on the Ubuntu forums. So big thanks to them.

These instructions have been tested on a fresh minimal install of CentOS 4.6 running in a VirtualBox VM.

Preparation

  1. Ensure that you have the rpmforge repo’s added to yum. See here for instructions.
  2. Update the install 
    yum update
  3. (If you are not installing onto a fresh minimal install) Remove ffmpeg, x264 and faad2 to avoid confusion. 
    yum remove ffmpeg x264 faad2 faad2-devel
  4. Install the necessary build tools 
    yum install gcc gcc-c++ automake autoconf libtool yasm git subversion
  5. Install the necessary libraries 
    yum install zlib-devel libmad-devel libvorbis-devel libtheora-devel lame-devel faac-devel a52dec-devel xvidcore-devel freetype-devel

Compile supporting libraries

  1. Compile & Install faad2 (for some reason I couldn’t get it to compile against the standard rpm version) 
    cd ~
wget http://downloads.sourceforge.net/faac/faad2-2.6.1.tar.gz
tar xzvf faad2-2.6.1.tar.gz
cd faad2
autoreconf -vif
./configure
make
make install
  2. Compile & Install GPAC 
    cd ~
wget http://downloads.sourceforge.net/gpac/gpac-0.4.4.tar.gz
tar -xzvf gpac-0.4.4.tar.gz
cd gpac
./configure
make
make install
make install-lib

    Note: if the compile fails with a osmozilla related error, please see here. I had to remove mozilla support to get it to compile.

  3. Update the links to the shared libs 
    echo '/usr/local/lib/' > /etc/ld.so.conf.d/gapc-1386.conf
ldconfig
  4. Compile & Install x264 
    cd ~
git clone git://git.videolan.org/x264.git
cd x264
./configure  --enable-pthread --enable-mp4-output --enable-shared
make
make install
  5. Update the links to the shared libs…again 
    ldconfig

Install ffmpeg

  1. cd ~
svn export svn://svn.mplayerhq.hu/ffmpeg/trunk ffmpeg
cd ffmpeg
./configure --prefix=/usr/local --disable-debug --enable-shared --enable-gpl --enable-nonfree --enable-postproc --enable-swscale --enable-pthreads --enable-x11grab --enable-liba52 --enable-libx264 --enable-libxvid --enable-libvorbis --enable-libfaac --enable-libfaad --enable-libmp3lame
make
make install
  2. If ffmpeg has problems finding shared libraries, set the LD_LIBRARY_PATH 
    echo 'LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib; export LD_LIBRARY_PATH' >> /etc/ld.so.conf
ldconfig

    I’m not convinced that this is the correct thing to do, or the correct way to do it…but it seems to work…

  3. All done.

Additional resources:

http://www.nazly.net/index.php?page=showevents&selTopic=230

http://www.tuxmachines.org/node/17063

]]> http://www.austenconstable.com/2008/08/06/howto-compiling-the-latest-ffmpeg-x264-on-centos-4/feed/ 4