[DOC] HandBrake Architectural Guide

[davidfstr]

I've written up all of my notes that I took while learning HandBrake. I imagine they will assist new would-be contributors to the project. May also be useful reference for regulars.

• HandBrake Architectural Guide: http://docs.google.com/View?id=dgkwt85m_73f7w73b9k

Embedded links:

• Work Objects: http://docs.google.com/View?docid=dgkwt85m_92hpfs7fzj
• do_job(): http://docs.google.com/View?docid=dgkwt85m_85z6qmc2d2
• HB Startup Notes: http://docs.google.com/View?docid=dgkwt85m_83fr54zkhq

See any errors?

What would be the best way to post this? Convert to Trac?

[s55]

Source Code Layout:

* build/
o contrib/ (External libraries that HB depends on)
* gtk/ (Windows GUI)
* libhb/ (HandBrake Core)
* macosx/ (Mac GUI)
* qt4/ (Linux GUI)
* test/ (Command Line Interface)

WinGui is in the Win/C# Folder, not GTK.
GTK is the Linux GUI
GT4 is an abandoned Linux GUI that hasn't been updated in a very long time.

[jbrjake]

Wow, nice. Yes, this should go in the Trac, on this page: http://trac.handbrake.fr/wiki/HandBrakeDesign

Adding new Trac users might still be broken, though, so it might have to go through an existing user.

[JohnAStebbins]

1/90000 sec ticks were chosen because this is the timebase defined by the mpeg spec for timestamps in program streams and handbrake was originally only for transcoding DVD's which are program streams.

Thanks for the docs

[dynaflash]

wow, nice. I also like it. Especially the pic of the hand written notes !

[eddyg]

Good stuff, thanks for that.

As for libsamplerate - it's used (no big surprise here) for changing the sample rate of the audio

This is when the input sample rate (in khz) is different to what you need it in the output, I use it to upsample flash video audio for kids snippets from 22Khz up to 48Khz, which (to my ear) sounds better due to some clever interpolation that libsamplerate does.

Cheers, Ed.

[davidfstr]

WinGui is in the Win/C# Folder, not GTK.

Well now I feel sheepish. For some reason my copy of the source that I use for browsing didn't have the win/ directory checked out.

1/90000 sec ticks were chosen because this is the timebase defined by the mpeg spec for timestamps in program streams and handbrake was originally only for transcoding DVD's which are program streams.

Updated.

As for libsamplerate - it's used (no big surprise here) for changing the sample rate of the audio

Updated.

Wow, nice. Yes, this should go in the Trac, on this page: http://trac.handbrake.fr/wiki/HandBrakeDesign

Adding new Trac users might still be broken, though, so it might have to go through an existing user.

Trac is broke? Would be cool to fix it, as I wouldn't be able to directly update any docs I create when they (inevitably) become out of date.

[davidfstr]

Have Trac access now. (Thanks jbrjake!)

So I'll work on integrating this into the Trac in the next day or two.

[davidfstr]

Finished converted the guide to Trac. After a good 2 hours of work...

Reachable via:

• WikiStart: http://trac.handbrake.fr/wiki
• Technical Documents: http://trac.handbrake.fr/wiki/TechnicalDocuments
• HandBrake Design and Implementation: http://trac.handbrake.fr/wiki/HandBrakeDesign
• HandBrake Architecture Guide: http://trac.handbrake.fr/wiki/HandBrakeArchitecture

A tad deep. Would it make sense to surface this directly on the "Technical Documents" page?
Update: Nah. It's probably fine.

[Rodeo]

Minor issue I noticed: http://trac.handbrake.fr/wiki/HandBrake ... VIMicrooft

cfr means constant framerate, not constant bitrate (and AVI requires constant framerate).

Unless that's also part of what should amuse us?

[davidfstr]

cfr means constant framerate, not constant bitrate (and AVI requires constant framerate).

Fixed.

Unless that's also part of what should amuse us?

Hehe. Speaking of amusements, I'll be adding some actual excerpts from the code soon - to cater to our users who wouldn't otherwise look.