Faq

What is FOBS?

Fobs project is a set of object oriented programming interfaces over the ffmpeg library. FFMpeg is the most complete open source library to work with media files. It is coded in C and completely multiplatform. Its only drawback is the great effort needed to build the most simple application: very complex API and few documentation. Fobs offers developers a simplified Object Oriented API. Actual bindings are: C++ and JMF.

Does Fobs offer all the functionality contained in ffmpeg?

No. FFMpeg offers much more functionality. Fobs is intended as a simplified API to work easily with media files. It was created within the scope of a video analysis research program at Universidad Politécnica de Madrid as the tool to access raw audio and video frames. Since then, it has evolved and is now offered as an open source product owned by Omnividea Multimedia.

What license is Fobs released under?

Fobs is released under the LPGL license, the same license used by ffmpeg. This fact allows to use fobs in the same conditions/projects you can use ffmpeg.

What is Fobs4JMF?

Fobs4JMF is part of the Fobs project. As Fobs goal is to provide object oriented APIs, we found it could be useful to add Java support in the form of a JMF PlugIn. Fobs4JMF binds the ffmpeg native library of codecs to the Java Media Framework, the Java API to work with media files. Using Fobs4JMF reports two advantages: the support of video and audio codecs supported by JMF is greatly improved and all the heavy computation processes involved in the encoding/decoding are performed natively.

Fobs4Jmf is having performance issues and/or missing sound. What is going on?

You are most likely using j2se 1.5. The latest release of Sun JVM does not seem to work flawlessly with JMF. Going back to j2se 1.4.2 solves many problems. If issues persist, check the forums to look for help in previous posts or ask for help.

Does Fobs4Jmf support audio-only / video-only files?

As of version 0.3pre2, fobs includes support for audio-only files. Fobs was created to work with video. Video-only files have been supported by fobs since the first version. Though audio was supported, internal time management was based on video timestamps, and so audio-only files were unable to be decoded using fobs4jmf. In version 0.3pre2, a fix for this problem has been added and audio files are supported (if codec/format is supported by ffmpeg). Enjoy it!

Are there any support resources available?

Fobs web site contains the necessary documentation to build, install and run fobs and fobs4jmf. Bug reports, functionality requests and general purpose user forum are available at the sourceforge.net project site.

What versions of Java does Fobs4JMF support?

Fobs is known to work fine with Java 1.4.2. While previous versions could work fine, it hasn't been tested. About Java 1.5, there seems to be sound issues in windows for the common JavaSoundRenderer. However, it works fine using the DirectAudioRenderer. A guide in the documents section explains how to make the DirectAudioRenderer your default renderer (just Windows users).

Can I have access to development versions?

Fobs project has a CVS server where you can download the latest development version. Use the following commands to connect:

cvs -d :pserver:anonymous@fobs.cvs.sf.net:/cvsroot/fobs login
cvs -d :pserver:anonymous@fobs.cvs.sf.net:/cvsroot/fobs co fobs-src

You won't be able to write your changes directly to the CVS server. This is a limitation of the SourceForge CVS service.

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