Libav Summer Of Code 2013

From MultimediaWiki
Jump to navigation Jump to search

How it works

Google's Summer of Code program is simple: you (the student) work on a project, full-time, during the whole summer, and you get assistance (advice, mentoring) from a seasoned Libav developer who knows his way around the project and has considerable standing in the community. By doing so, you'll learn to operate in an opensource project, you'll get relevant coding experience, and you'll have a chance at earning money while doing fun stuff during the summer. So, you need a project, a mentor, do a qualification task (see below) so we can quickly assess how good a candidate we feel you'll be for the program, and then you can apply.

Selecting a project

Below, you'll find two lists of projects:

  • Projects with a mentor
  • Projects without a mentor

If you choose a project with a mentor, talk to that mentor (see below) and select a suitable qualification task. Once completed, you're eligible for participating in our Summer of Code program. If you choose a project without a mentor, your first job is to find a mentor (see below). Then, once you've found a mentor, continue as before. If you don't like any of the projects, you're free to define your own project and find a mentor as mentioned before (see below for caveats).

Contacting developers/mentors

Once you've found a project (with or without mentor), start talking to the developers of the Libav project. We can often be found on IRC, and you can talk to us on mailinglists also. Hop on channel #libav-devel, or talk to us on Here, you'll be able to ask around for mentors for projects without a mentor if you need to. If you're trying to define your own project, explain (with reasonable amount of detail) what you intend to achieve and why you think your project should be in our Summer of Code program. Once you've found a mentor, you're good to start your qualification task.

Note that the self-selected mentor needs to have considerable standing in the community to be eligible for mentoring. Likewise, if you choose to define your own Summer of Code project, some community members of considerable standing need to vouch for your project.

Your qualification task

The goal of a qualification task is to see if the mentor and student feel that, together, they will be able to finish the project of their choice. More specifically, the mentor will want to test whether the student has the skills and work ethics to complete a large coding project in a limited amount of time. The student will want to make sure that the mentor provides (useful) assistance when necessary. Therefore, students should select a mentor and a Summer of Code project before starting their work on a qualification task. The qualification task is often (but not necessarily) related to the selected project. For example, if your project will be to reverse engineer a new video codec, the qualification task may be to write a partial bitstream parser for that codec. If your project is to write a muxer for a container format, the qualification task may be to write the code to write the stream header.

There will be a second qualification task for every student: Pick a file of moderate size and reformat it in proper K&R style. The goal of this task is twofold: First it familiarizes students with the style that they will have to write their code in, second it demonstrates that students are able to submit patches from git and go through our review process.


While you're working on your qualification task, apply at The degree (and detail) with which you've finished your qualification task will determine how likely your project is to be selected. In the past few years, students that completely finished their qualification task always got selected as Summer of Code students, but that may vary depending on the number of spots we get assigned by Google, and the number of students that apply.

1st Tier Project Proposals

1st tier project proposals are project ideas that are reasonably well defined AND have a mentor volunteered.

Hardware Acceleration API

Libav has two different and incomplete api to provide hardware acceleration wrapping, the project should provide a better abstraction and migrate the currently implemented ones and additional provide more.

  • Draft the API (that will require knowledge of libavcodec)
  • Port vaapi/hwaccel to the new API.
  • Port vdpau to the new API
  • Implement Freescale VPU support
  • Implement TI dce support

Mentor: Luca Barbato

VP9 Native Decoder

The WebM team is refining the evolution of their VP8 codec using a number of additional tools and tunings, the project involves providing a baseline decoder as first step and optimize it to be at least as fast as the vpx one on one of the most used architectures (arm and x86_64).

Mentor: Luca Barbato

Webp Lossless Native codec and webp Lossy decoder

The webp is a quite promising image format that could superceed JPEG and PNG as common format for web images, it leverages vp8 for lossy encoding and uses a relatively simple original format for the lossless part

The project is split in a number of easy tasks, such as writing a decoder for both the lossy and the lossless mode and a much harder task that is providing a good encoder for the lossless part, at least. (exceptional praise for producing a good lossy encoder but it is not required).

Mentor: Luca Barbato

Native DVD support

Currently most of the opensource support for DVD is available through the use of libdvdread and libdvdnav, currently there is some effort to unify them in a single library (libdvd5). An additional step would be factor it in the libav codebase the non interactive part of it to leverage even more code and leave as stand alone library the parts that require some kind of interaction.

Mentor: Diego Pettenò