Development: The DVB Decoder Challenge: Difference between revisions

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== Color Correction, the Gamma Question ==
== Color Correction, the Gamma Question ==


Computer Monitors and Video Projectors have a different Gamma Curve than Television Screens. Thus you need to apply a proper correction curve to the display.
Computer Monitors and Video Projectors have a different Gamma Curve than Television Screens. Thus you need to apply a proper correction curve to the display. All common graphics libraries like SDL, DirectFB and SDL provide an API to set up the Gamma Color Lookup Tables. Not hard to do, just has to be done correctly otherwise you risk weak colors on the display.

All common graphics libraries like SDL, DirectFB and SDL provide an API to set up the Gamma Color Lookup Tables. Not hard to do, just has to be done correctly otherwise you risk weak colors on the display.

Revision as of 15:05, 27 September 2004

Introduction

When implementing a Hard- or Software MPEG2 Decoder one will encounter several challenges, most of them are not too hard to solve but very DVB-specific and can be quite annoying if not properly handled.

So this page tries to list them, to discuss common approaches and to outline elegant solutions.


Audio/Video Sync

The STC sync problem

Screen/Decoder Sync Aliasing

Audio Clock pitching

Color Correction, the Gamma Question

Computer Monitors and Video Projectors have a different Gamma Curve than Television Screens. Thus you need to apply a proper correction curve to the display. All common graphics libraries like SDL, DirectFB and SDL provide an API to set up the Gamma Color Lookup Tables. Not hard to do, just has to be done correctly otherwise you risk weak colors on the display.