Difference between revisions of "VLC Dev Projects"

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This is a list of small independent improvements to {{VLC}} for which we are looking for interested developers, because we simply don't have enough time.
+
This is a list of small independent improvements to VLC for which we are looking for interested developers, because we simply don't have enough time.
  
 
These do not require advanced knowledge of VLC internals but they can still vastly improve many parts of VLC
 
These do not require advanced knowledge of VLC internals but they can still vastly improve many parts of VLC
Line 5: Line 5:
 
For each project, we list a contact person, who knows the subject best and who will be able to assist you if you are interested in working on these. We generally are very often present on irc.videolan.org, chan #videolan, so please don't hesitate to drop by or to send a mail if you are interested in a given problem (our mail adresses are generally <nick>@videolan.org).
 
For each project, we list a contact person, who knows the subject best and who will be able to assist you if you are interested in working on these. We generally are very often present on irc.videolan.org, chan #videolan, so please don't hesitate to drop by or to send a mail if you are interested in a given problem (our mail adresses are generally <nick>@videolan.org).
  
'''Be careful, some projects may be unrelated, or deprecated, because of fast evolving software! Ask before !'''
+
We also have a number of "easy" bugs. You can check them out [http://trac.videolan.org/vlc/query?status=new&status=assigned&status=reopened&difficulty=easy&order=priority` here]
  
 
= Easy projects =
 
= Easy projects =
 
These projects are junior projects, the most easy ones to do, that require minimum knowledge of VLC.
 
 
We also have a number of "easy" bugs. You can check them out [http://trac.videolan.org/vlc/query?status=new&status=assigned&status=reopened&difficulty=easy&order=priority` here]
 
 
== Code Janitorial ==
 
It basically means to clean the code, it is helpful for all programmers. It helps to find bugs, and is a good way to learn about VLC's internals.
 
 
It is covered in the [[Code Janitorial]] section.
 
 
if you feel confortable with english language, be sure to have a look to  [[QT4StringsReview|the QT4 Strings Review]].
 
  
 
== Video Filters ==
 
== Video Filters ==
Line 26: Line 15:
 
[http://movavi.com/enhancemovie/filters.html list of filters] from a commercial product.
 
[http://movavi.com/enhancemovie/filters.html list of filters] from a commercial product.
  
You can start the code [http://trac.videolan.org/vlc/browser/trunk/modules/video_filter/ here].
+
You can start the code [http://git.videolan.org/?p=vlc.git;a=tree;f=modules/video_filter here].
  
 +
== Subtitles improvements ==
 +
{{VLC}} does not support all the styles for a lot of subtitles type.
 +
Take a look at {{VLCSourceFile|modules/codec/subsdec.c}} to start coding.
  
== LastFM radios ==
+
= Network =  
  
http://gabistapler.de/blog/index.php?/archives/268-Play-last.fm-streams-without-the-player.html
+
== RTCP support ==
  
Talk to dionoea or funman
+
Our RTSP implementation (for broadcasting and video on demand) does not support the RTCP protocol. This is a must to have a real support for RTSP.
 +
Some work has already been started, but there is still much to do.
  
= Network =
+
Contact: [[User:JPSaman|JPSaman]]
  
 
== Performant VLC streaming server ==
 
== Performant VLC streaming server ==
Line 41: Line 34:
 
There are many bottlenecks currently limiting the performance and scalability of VLC as a streaming server:
 
There are many bottlenecks currently limiting the performance and scalability of VLC as a streaming server:
 
* The I/O blocks are linear, which implies lots of avoidable memory copying and dynamic memory allocations (particularly in the streaming output).
 
* The I/O blocks are linear, which implies lots of avoidable memory copying and dynamic memory allocations (particularly in the streaming output).
* mdate() (the timestamping function) is invoked in too many places to count them; but it is not a cheap operation on modern systems and should be avoided on the fast path. Ideally, a single thread would only need to call mdate() at most once per wake-up. In some case, mdate() is only used for debugging purpose which is really inefficient.
+
* <s>mdate() (the timestamping function) is invoked in too many places to count them; but it is not a cheap operation on modern systems and should be avoided on the fast path. Ideally, a single thread would only need to call mdate() at most once per wake-up. In some case, mdate() is only used for debugging purpose which is really inefficient.</s>
* The HTTP/RTSP core is single-threaded. This prevents scaling to SMP systems (which are the norm on server-side nowadays) properly. This also implies not very scalable I/O event polling. Finally, this gets problematic if one HTTP/RTSP client triggers a computationally intensive operation (such as establishing a TLS context if HTTP/SSL is used).
+
* The HTTP/RTSP core is single-threaded. This prevents scaling to SMP systems (which are the norm on server-side nowadays) properly. This also implies not very scalable I/O event polling. This also becomes problematic when one HTTP/RTSP client triggers a computationally intensive operation (such as establishing a TLS context if HTTP/SSL is used).
 
* There are many dynamic memory allocations that could be avoided. Video filters and codecs are very careful about this, but the stream output plugins are not. In many case, a stack-based buffer can be used (stack buffer, has constant time fast lock-less allocation, and needs not be freed explicitly) instead.
 
* There are many dynamic memory allocations that could be avoided. Video filters and codecs are very careful about this, but the stream output plugins are not. In many case, a stack-based buffer can be used (stack buffer, has constant time fast lock-less allocation, and needs not be freed explicitly) instead.
* The messaging subsystems might be adding more locking (needs checking); this should be avoided particularly if the message is anyway ignord (e.g. debug message in non-debug mode).
+
* <s>The messaging subsystems might be adding more locking (needs checking); this should be avoided particularly if the message is anyway ignord (e.g. debug message in non-debug mode).</s>
 +
* Interleaved RTP in RTSP is not supported.
  
 
Other improvements that would be particularly benefitial on the server side:
 
Other improvements that would be particularly benefitial on the server side:
  
 
* Memory allocation failure are not always duly handled. In some cases, that could potentially be leveraged by a client to crash a VLC server by causing a very large allocation attempt.
 
* Memory allocation failure are not always duly handled. In some cases, that could potentially be leveraged by a client to crash a VLC server by causing a very large allocation attempt.
* Rewrite and revive the root wrapper to allow VLC to bind to the RTSP (554) port while not retaining root privileges.
+
* <s>Rewrite and revive the root wrapper to allow VLC to bind to the RTSP (554) port while not retaining root privileges.</s>
  
 
Contact: [[User:Courmisch|Courmisch]]
 
Contact: [[User:Courmisch|Courmisch]]
Line 55: Line 49:
 
= Inputs =
 
= Inputs =
  
== Windows Media Center (WMC) IR Remote Control ==
+
== DVB support for Windows ==
 +
 
 +
DVB is the norm for :
 +
* Digital Terrestrial TV (aka DVB-T)
 +
* Digital Cable TV (aka DVB-C)
 +
* Digital Satellite TV (aka DVB-S)
 +
 
 +
Several DVB input cards exist. We support these on Linux, but not on Windows. For Windows, we need to support so-called BDA drivers.
  
Basic Controls work (e.g. Volume, Mute etc), but I would like to get Play/Pause/Stop/DVD Menu etc to work!
+
The problem is that we don't have both the time and the required hardware on Windows comps.
  
Contact: [[User:some1|some1]]
+
This project is probably not terribly complex, but you need the hardware.
 +
Someone has already began it on the forum, so start from there.
 +
 
 +
== V4L2 support ==
 +
 
 +
VLC currently has a pvr module and a v4l (video for linux) module.
 +
However
 +
* some cards are only supported in the new v4l2 API
 +
* The linux kernel will soon drop v4l support
 +
 
 +
So if someone could update VLC's current modules to work with V4L2 and the new ivtv api, this would be a welcome addition.
 +
This is not a very difficult project, but you will need to have the hardware to test against.
 +
The code has been began, so it should not be too difficult.
  
 
= Video =  
 
= Video =  
Line 66: Line 79:
  
 
DirectX 9 features some improvements that we could use in our video output
 
DirectX 9 features some improvements that we could use in our video output
 
Contact: [[User:Quovodis|Quovodis]]
 
  
 
== Improvements to the X11 video output ==
 
== Improvements to the X11 video output ==
  
 
Fullscreen support to improve .
 
Fullscreen support to improve .
 
== Pixel shaders in OpenGL video output ==
 
 
It would be nice to have a small proof of concept video output which takes care of chroma conversion using pixel shaders.
 
 
Contact: [[User:Dionoea|dionoea]]
 
  
 
= Interfaces =  
 
= Interfaces =  
Line 85: Line 90:
 
This is a big subject, that has barely started. Interested persons will need to work closely with existing developers to implement this.
 
This is a big subject, that has barely started. Interested persons will need to work closely with existing developers to implement this.
 
Not much information is available yet. The idea is to make streaming very easy, and yet powerful by using parametrable profiles. These could be used either by the graphical interfaces or through HTTP/command line interfaces
 
Not much information is available yet. The idea is to make streaming very easy, and yet powerful by using parametrable profiles. These could be used either by the graphical interfaces or through HTTP/command line interfaces
 
Contact: [[User:Zorglub|Zorglub]]
 
 
== VLC.app rewrite using the Mac OS X Framework ==
 
 
See [[Mac_OS_X_Framework_VLC_app_Rewrite]]
 
 
Contact: [[User:Pdherbemont|Pdherbemont]]
 
  
 
= Playlist =  
 
= Playlist =  
Line 99: Line 96:
  
 
Our current podcast support is very weak. We can read them, but that's all. We need a real infrastructure to handle them correctly. This will require some changes to the playlist code, so you will need to work closely with existing developers.
 
Our current podcast support is very weak. We can read them, but that's all. We need a real infrastructure to handle them correctly. This will require some changes to the playlist code, so you will need to work closely with existing developers.
 
Contacts: [[User:Dionoea|Dionoea]] [[User:Zorglub|Zorglub]]
 
  
 
== Improved ASX support ==
 
== Improved ASX support ==
Line 106: Line 101:
 
ASX is a playlist format used by Microsoft stuff. We can read it but we could do much better. More information is available at  
 
ASX is a playlist format used by Microsoft stuff. We can read it but we could do much better. More information is available at  
 
https://trac.videolan.org/vlc/ticket/20
 
https://trac.videolan.org/vlc/ticket/20
 
Contact: [[User:Dnumgis|Dnumgis]]
 
  
 
== Disc probing ==
 
== Disc probing ==
  
 
We currently have some miscellaneous code to detect discs (DVDs, Audio CDs, ...) but it's a bit scattered and it could be used much better in the playlist.
 
We currently have some miscellaneous code to detect discs (DVDs, Audio CDs, ...) but it's a bit scattered and it could be used much better in the playlist.
 
Contact: [[User:Zorglub|Zorglub]]
 
  
 
== Live folders ==  
 
== Live folders ==  
Line 123: Line 114:
 
It might require some work to be able to do this in Linux, Windows and OS X, but the current developers will of course be able to help on these.
 
It might require some work to be able to do this in Linux, Windows and OS X, but the current developers will of course be able to help on these.
  
Contacts: [[User:Zorglub|Zorglub]] [[User:The DJ|The DJ]]
+
= Misc =  
 
 
=== Hint MP4/MOV Files ===
 
 
 
Add video and audio hint tracks as the output file is muxed. Resulting files can be streamed from RTSP server with trickplay, like DSS/QTSS. Probably requires use of GPAC libraries.
 
 
 
 
 
= Projects running =
 
 
 
== Subtitles improvements ==
 
{{VLC}} does not support all the styles for a lot of subtitles type.
 
Take a look at [http://trac.videolan.org/vlc/browser/trunk/modules/codec/subtitles/subsdec.c here] to start coding.
 
 
 
Contact bitmap
 
 
 
= Finished projects =
 
 
 
==Audioscrobbler==
 
 
A [http://www.audioscrobbler.net/ Audioscrobbler] VLC Plug-in for the social music network [http://www.last.fm Last.Fm]<br />
 
 
Plugin is finished, now part of vlc 0.9.0 (development version). Done by [[User:funman|funman]]
 
 
 
 
 
 
 
  
 
== DBus Integration ==
 
== DBus Integration ==
Line 155: Line 122:
 
We would like VLC to be able to use it so that other programs can interact with vlc (start/stop, know what is being played, ...)
 
We would like VLC to be able to use it so that other programs can interact with vlc (start/stop, know what is being played, ...)
  
Work is well advanced, see [[DBus]], by funman and Mr_Mirsal
+
Work is well advanced, see [[DBus]]
 
 
Contact: [[User:Xtophe|Xtophe]], [[User:funman|funman]]
 
 
 
 
 
 
 
== RTCP support ==
 
 
 
Our RTSP implementation (for broadcasting and video on demand) does not support the RTCP protocol. This is a must to have a real support for RTSP.
 
Some work has already been started, but there is still much to do.
 
 
 
Contact: [[User:JPSaman|JPSaman]]
 
  
[[Category:Coding]] [[Category:Activities]]
+
[[Category:Coding]]
 +
[[Category:Development]]

Latest revision as of 09:57, 16 February 2019

This is a list of small independent improvements to VLC for which we are looking for interested developers, because we simply don't have enough time.

These do not require advanced knowledge of VLC internals but they can still vastly improve many parts of VLC

For each project, we list a contact person, who knows the subject best and who will be able to assist you if you are interested in working on these. We generally are very often present on irc.videolan.org, chan #videolan, so please don't hesitate to drop by or to send a mail if you are interested in a given problem (our mail adresses are generally <nick>@videolan.org).

We also have a number of "easy" bugs. You can check them out here

Easy projects

Video Filters

You can do video filters for VLC media player.

You can inspire yourself on this list of filters from a commercial product.

You can start the code here.

Subtitles improvements

VLC media player does not support all the styles for a lot of subtitles type. Take a look at modules/codec/subsdec.c to start coding.

Network

RTCP support

Our RTSP implementation (for broadcasting and video on demand) does not support the RTCP protocol. This is a must to have a real support for RTSP. Some work has already been started, but there is still much to do.

Contact: JPSaman

Performant VLC streaming server

There are many bottlenecks currently limiting the performance and scalability of VLC as a streaming server:

  • The I/O blocks are linear, which implies lots of avoidable memory copying and dynamic memory allocations (particularly in the streaming output).
  • mdate() (the timestamping function) is invoked in too many places to count them; but it is not a cheap operation on modern systems and should be avoided on the fast path. Ideally, a single thread would only need to call mdate() at most once per wake-up. In some case, mdate() is only used for debugging purpose which is really inefficient.
  • The HTTP/RTSP core is single-threaded. This prevents scaling to SMP systems (which are the norm on server-side nowadays) properly. This also implies not very scalable I/O event polling. This also becomes problematic when one HTTP/RTSP client triggers a computationally intensive operation (such as establishing a TLS context if HTTP/SSL is used).
  • There are many dynamic memory allocations that could be avoided. Video filters and codecs are very careful about this, but the stream output plugins are not. In many case, a stack-based buffer can be used (stack buffer, has constant time fast lock-less allocation, and needs not be freed explicitly) instead.
  • The messaging subsystems might be adding more locking (needs checking); this should be avoided particularly if the message is anyway ignord (e.g. debug message in non-debug mode).
  • Interleaved RTP in RTSP is not supported.

Other improvements that would be particularly benefitial on the server side:

  • Memory allocation failure are not always duly handled. In some cases, that could potentially be leveraged by a client to crash a VLC server by causing a very large allocation attempt.
  • Rewrite and revive the root wrapper to allow VLC to bind to the RTSP (554) port while not retaining root privileges.

Contact: Courmisch

Inputs

DVB support for Windows

DVB is the norm for :

  • Digital Terrestrial TV (aka DVB-T)
  • Digital Cable TV (aka DVB-C)
  • Digital Satellite TV (aka DVB-S)

Several DVB input cards exist. We support these on Linux, but not on Windows. For Windows, we need to support so-called BDA drivers.

The problem is that we don't have both the time and the required hardware on Windows comps.

This project is probably not terribly complex, but you need the hardware. Someone has already began it on the forum, so start from there.

V4L2 support

VLC currently has a pvr module and a v4l (video for linux) module. However

  • some cards are only supported in the new v4l2 API
  • The linux kernel will soon drop v4l support

So if someone could update VLC's current modules to work with V4L2 and the new ivtv api, this would be a welcome addition. This is not a very difficult project, but you will need to have the hardware to test against. The code has been began, so it should not be too difficult.

Video

DirectX 9 video output

DirectX 9 features some improvements that we could use in our video output

Improvements to the X11 video output

Fullscreen support to improve .

Interfaces

Streaming profiles

This is a big subject, that has barely started. Interested persons will need to work closely with existing developers to implement this. Not much information is available yet. The idea is to make streaming very easy, and yet powerful by using parametrable profiles. These could be used either by the graphical interfaces or through HTTP/command line interfaces

Playlist

Improved Podcast support

Our current podcast support is very weak. We can read them, but that's all. We need a real infrastructure to handle them correctly. This will require some changes to the playlist code, so you will need to work closely with existing developers.

Improved ASX support

ASX is a playlist format used by Microsoft stuff. We can read it but we could do much better. More information is available at https://trac.videolan.org/vlc/ticket/20

Disc probing

We currently have some miscellaneous code to detect discs (DVDs, Audio CDs, ...) but it's a bit scattered and it could be used much better in the playlist.

Live folders

Some programs support so-called live folders. You add a folder to the playlist, and if the files in the folder are changed, the changes are copied to the playlist.

Having this would of course be great :)

It might require some work to be able to do this in Linux, Windows and OS X, but the current developers will of course be able to help on these.

Misc

DBus Integration

DBus is a communication mechanism for Linux (mainly).

We would like VLC to be able to use it so that other programs can interact with vlc (start/stop, know what is being played, ...)

Work is well advanced, see DBus