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FFMPEG Cropping and Re-sizing (order matters)

I discovered something whilst trying to crop and re-size a video with FFMPEG: the order of switches actually matters! I couldn't find any mention of this in the documentation, and nowhere could I find an explanation of why my video was being cropped after it was resized. The video I was re-encoding had some fuzziness at the top, and an ugly black border down the right-hand side. I wanted to remove these, but have a fixed output size.

Here's an example. Our input file, input.avi is a 640x480 video.

We run the following 2 commands:

ffmpeg -i input.avi -s qvga -croptop 8 -cropright 22 output1.avi
ffmpeg -i input.avi -croptop 8 -cropright 22 -s qvga output2.avi

Notice that in the first case, we've set the size first (qvga means 320x240).

In the second case we set the cropping first.

Now let's look at the output with: file *.avi.

input.avi: RIFF (little-endian) data, AVI, 640 x 480, 25.00 fps, video: XviD, audio: MPEG-1 Layer 3 (stereo, 44100 Hz)
output1.avi: RIFF (little-endian) data, AVI, 298 x 232, 25.00 fps, video: FFMpeg MPEG-4, audio: MPEG-1 Layer 1 or 2 (stereo, 44100 Hz)
output2.avi: RIFF (little-endian) data, AVI, 320 x 240, 25.00 fps, video: FFMpeg MPEG-4, audio: MPEG-1 Layer 1 or 2 (stereo, 44100 Hz)

As you can see, the first output file has its dimensions cropped after resizing. The second one before, and its the second one I wanted, cropping the video first, then resizing it.

I have never encountered a command-line app where the order of the switches actually mattered, until now. I don't know how many other ffmpeg switches this also applies to, but I thought I'd share it as I personally couldn't find anything about it elsewhere.

Hope this is helpful!

Thom

 

Testing the linux.com blog platform

seems to be fairly cool for sure!

 I think that the pop-up editor is a cool feature.

 Oh, sorry, I mean:

 

Hello world!

 

Andrew.

 

Likewise Software Ships with SUSE Linux Enterprise Desktop 11 from Novell

 

Integrates SUSE Linux Desktop with Microsoft Networks

 

BELLEVUE, Wash., May 19, 2009 - Likewise announced today that its Likewise Enterprise offering will ship as part of SUSE Linux Enterprise Desktop 11 from Novell.

 

Likewise Enterprise securely connects computers running  SUSE Linux Enterprise Desktop 11 with Microsoft Active Directory -- making it easy to authenticate users, control access to applications and data, centrally manage settings with group policies and create reports for regulatory audits.

 

"Likewise is seeing acceleration in the number of our Linux desktop projects," said Barry Crist, CEO of Likewise. "Novell is a natural partner for us as it has been a pioneer in the area of Linux desktops with SUSE Linux Enterprise Desktop. The company clearly understands the widespread demand to offer better integration into Active Directory environments."

 

The group policies in Likewise Enterprise let system administrators manage the security settings of SUSE Linux Enterprise Desktop computers and users from a central system. Likewise Enterprise also includes GNOME group policies to control SUSE Linux Enterprise Desktop user and computer settings -- policies that are based on the GNOME GConf project to define preferences like the default web browser or when to lock down a desktop.

 

"Likewise helps us meet the requirements that our customers demand; the need for advanced Active Directory integration including support for AD security settings and group policy," said Guy Lunardi, director for Client Preloads at Novell. "SUSE Linux Enterprise Desktop 11 is the most interoperable Linux desktop in the industry and in combination with Likewise Enterprise offers a highly-scalable enterprise solution for large Linux desktop deployments."

 

Under the terms of the agreement between Likewise and Novell, all Novell customers who buy SUSE Linux Enterprise Desktop 11 will get Likewise Enterprise, and it will be part of the SUSE Linux Enterprise Desktop software repositories.

 

"Many organizations are integrating their Linux systems into Active Directory because of the centralized identity and policy management capabilities, with the added benefits of enhanced authentication and sign-on reduction," noted Mark Diodati, senior identity and security analyst at Burton Group. "The embedding of the Active Directory component into the Linux operating system should simplify enterprise deployments."

 

Likewise Enterprise addresses the authentication, auditing, and reporting needs of companies running multiple operating systems in their network. Likewise Enterprise is a simple upgrade for customers who have installed Likewise Open and want to use group policies to manage their mixed environment and use the auditing features of Likewise Enterprise to view access reports. The auditing features help companies comply with regulatory requirements, such as those of Sarbanes-Oxley.

 

About Likewise

Likewise provides identity management solutions that improve security, enhance operational efficiency, and help achieve regulatory compliance in mixed networks. Likewise Open lets large organizations securely authenticate Linux, Unix, and Mac systems with Active Directory, a popular and proven unified directory system. Likewise Enterprise includes all the core authentication technology that comes with Likewise Open, plus world-class modules for access control, migration, group policy, auditing, and reporting. For more information, visit http://www.likewise.com/.

 

Likewise is a trademark of Likewise Software. All other trademarks referenced herein are the property of their respective owners.

 

Effortless XML manipulation with Groovy slurping

To be a successful software developer in this day and age, you need a set of tools that makes dealing with XML effortless. Groovy introduces new and better ways to create and process XML. With the help of some examples, this article shows you how Groovy makes building and parsing XML refreshingly simple.
 

Convert maildir to mbox

Article Source: http://www.cmdln.org
Date: March 13th 2009

Note, there is a short story before the main course.

I recently had a customer leave. It’s never good to lose a customer. They left not because of any service issues but because its hard for them to understand that I am not a web designer. I provided hosting service for them, and I tried to make it clear that they should find a web desinger and someone to maintain their site because that is not something I specialize in or have any interest in doing. At any rate this of course leads to them finding a designer who wants to move their site to some other host. I have no problems with that whatever makes the maintainer happy since he is the one (more…)

 

Come scoprire quale cartella occupa troppo spazio

Come possiamo sapere come e' distribuito lo spazio sul disco del nostro "amato" server Windows??

Il SO di Redmond non ci viene incontro in questo ingrato compito e infatti non troviamo nessun comando che ci possa dare un'indicazione al volo di quale cartella occupa di piu'. Possiamo al piu' avere un riscontro su spazio occupato e spazio libero su una unita', ma come fare per avere una lista di cartelle in base alla loro occupazione?

Utilizzando una macchina Linux (in particolare Ubuntu 9.04 nei prossimi esempi)! Come prima cosa montiamo il disco del server in una directory del nostro client:

esoso@UBW099015D:~/backups$ sudo mount -t smbfs //SERVERNAME/c$/ source/ -o user=DOMAIN/USERNAME,uid=1000,gid=1000

A questo punto il disco C: del server e' montato nella cartella locale source/ e possiamo trattarla come tale.

Il comando che andremo ad usare e' du (man du): ci restituisce come output una lista di tutti i files e le directory contenute nella dir corrente

esoso@UBW099015D:~/backups/source$ du
132 ./WINDOWS/WinSxS/x86_Microsoft.Windows.Networking.RtcRes_6595b64144ccf1df_5.2.2.1830_en_920EB233
356 ./WINDOWS/WinSxS/x86_Microsoft.Windows.WinHTTP_6595b64144ccf1df_5.1.3790.1830_x-ww_74150EFB
356 ./WINDOWS/WinSxS/x86_Microsoft.Windows.WinHTTP_6595b64144ccf1df_5.1.3790.3262_x-ww_CE315432
21246 ./WINDOWS/WinSxS
4019928 ./WINDOWS
0 ./wmpub/wmiislog
0 ./wmpub
5443042 .

L'output di du e' molto semplice: due colonne, la prima indica lo spazio occupato (in Kb) e la seconda il percorso completo del file o della cartella analizzata.

Cosi' facendo pero' il comando sbrodola una lista interminabile e difficilmente analizzabile; possiamo pero' utilizzare un flag molto comodo --max-depth=1; a questo punto l'output diventera' un po piu' leggibile perche' il comando non discendera' nelle directory di livello superiore al valore del flag (1 in questo caso):

esoso@UBW099015D:~/backups/source$ du --max-depth=1
0 ./Config.Msi
428498 ./Documents and Settings
25087 ./IBMTOOLS
783484 ./Program Files
1 ./RECYCLER
20 ./System Volume Information
126980 ./TEMP
4019928 ./WINDOWS
0 ./wmpub
5444698 .

Ci siamo quasi!! Pero' sarebbe molto comodo avere un ordinamento dell'output basato sulla dimensione delle cartelle e non in base al loro nome; ci dobbiamo affidare al pipe e al comando sort per questo:

esoso@UBW099015D:~/backups/source$ du --max-depth=1 | sort -n -r
5448898 .
4019932 ./WINDOWS
783484 ./Program Files
428498 ./Documents and Settings
126980 ./TEMP
25087 ./IBMTOOLS
20 ./System Volume Information
1 ./RECYCLER
0 ./wmpub
0 ./Config.Msi

Sort rielabora l'output di du e ce lo presenta allo stesso modo pero' ordinato per dimensione (-n numeric sort) e dal piu invadente al meno esoso. Con una riga di comando possiamo quindi avere sotto controllo ogni singola cartella del server che dobbiamo ripulire, quindi sotto con le pulizie di Pasqua!!!!

 

My Cult Envy

 Sexy Tattoo Fangirl

 I have a serious cult envy.  This of course is referring to the largest cult on the entire technological landscape.  Apple cults.

How I envy they're pretty girls with tattoos. We seem to fall short with dudes so ugly I might as well be look in the mirror. I envy the Apple Blogs and rumor sites that 'leak' sensitive 'information' about the newest products and updates. Again, all we have is SVN, Alpha builds, and screen shot tours.

The big question is what can we do to have that healthy-unhealthy following? I've kicked around some ideas my self. I even thought about buying Linus or Shuttleworth a black turtleneck. I would send one to Stallman, but I don't feel like knitting one by hand.

Even YouTube, (my beloved YouTube!) is lacking in quality resemblance of Linux love. I can find hours upon hours of Apple tips, trick, and solutions that vary from quick and easy to incredibly complex. Damn near all you get on YouTube when you search Linux is a bunch of Compiz Cube videos. Man, the cube is cool though ain't it?

What can we do to improve the cult situation in Linux? More importantly where is the sexy tattooed Linux fangirls?

 

Xmind for SF nomination

Show your support...
 

Linux documentation catalog

I collected Linux documentation from LDP and other sources to single catalog
        - http://www.makelinux.net/reference
Your comments are welcome
.

Please help to promote the catalog.

 

My thoughts on Linux and Asia in 2009

My thoughts on Linux and Asia in 2009

First of all, I think it would be right to let people know where I'm from, so that they would understand the relevance of my views. I'm an Asian myself , from Singapore. And why I chose to write this article is for 2 major reasons. Most of the articles I read about Linux comes from North America and Europe. Hence I think it would be interesting for people to learn more about the Asian perspective on Linux, in an English written article, that is. The second reason is to beckon for a greater presence of Linux in Asia.
Let me "sell" you the idea of why I think Linux will do better in Asia. First of all, asia is big conglomerate of hugely different cultures and if you've ever been to asia, you would realise that in many places, Asia are on par and if not much better than the rest of world, in terms of choices. Take for example, in China and many other parts in Asia, you'll see people using different kinds of cellphones, of different makers. Many of brands are not available in Europe or America. And if you go into the features, there are more features per handphone than the you get in Europe and America. Many of these phones are clones or copies of Western brands, but with extra features and lower retail cost. So in terms of cellphone technology, I think Asia is leading. Sometimes my western friends see the phones we have here, they wonder why they are still carrying that black box which they call a phone. And this culture of having more choices, is the one of the fundamentals of the Linux/Gnu philosophy isn't it? Asians love choices, period.
The next thing is that one of the major reasons I think why Linux is crawling throught the computing market share, is mainly due to the fact that it is mostly advertised or encouraged in the western world. What these Linux companies or distros don't understand is, there is actually a bigger market in Asia. And it will even bigger, as computer literacy sky-rockets in the near future in Asia. The reason why Microsoft dominates so well in the western world is that, the western world grew up in the world of Microsoft. So most western people, are used to using Windows, and thus it became the de facto OS in school and work. Asia is different. Many asian countries are still developing their literacy level, hence this is the best time to enter the market. Linux being free and open-source, it makes it easy to propagate itself in Asia. And if Asian students learn Linux in schools, it would easily be their OS of choice when they grow up. Hence I don't understand why the Linux world is neglecting this part of the world. The greater part of the world that is.
Lastly, Asia is more aggressive and competitive that most of the western world in my opinion. Hence Linux would do better here in a more competitive way. If you look at the top universities of the world and look at the top 20 % of the cohort of students, you'll find many asians there. This is not a show of elitism or racism, but it's just an example to illlustrate the fact that there are many bright young minds in Asia, which could contribute well to the world of Linux..
But to really succeed in Asia, I think Linux community have to work harder to develop softwares or applications that are supportive of unicode and other Asian language. There are still many apps that are written purely for the English-speaking world and I still find many files with Chinese filenames that are unable to be displayed in multimedia and file managers alike. My personal favorite file manager (midnight commander) wouldn't display Chinese fonts is an example.
So here I beckon to all the major Linux companies and distros, if you haven't had a branch/wing/counterpart here in Asia, you don't know what you have been missing out.=) Singapore's a good place to start, at least we are English-speaking and we position ourselves between the East and the West since the dawn of our humble history.

 

Who has better virtualization, HP-UX, Solaris, or AIX?

Why is virtualization so important? The short answer is that virtualization enables businesses to lower their technology Total Cost of Ownership (TCO), while increasing their Return on Investment (ROI). What do the top UNIX vendors have to offer with respect to virtualization? Find out what virtualization is more scalable. Here's a look at HP's Virtual Server Environment (VSE), Sun's xVM, and IBM's PowerVM.

 

 
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