Title :
Global brightness-variation compensation for video coding
Author :
Kamikura, Kazuto ; Watanabe, Hiroshi ; Jozawa, Hirohisa ; Kotera, Hiroshi ; Ichinose, Susumu
Author_Institution :
NTT Human Interface Labs., Kanagawa, Japan
fDate :
12/1/1998 12:00:00 AM
Abstract :
A global brightness-variation compensation (GBC) scheme is proposed to improve the coding efficiency for video scenes that contain global brightness-variations caused by fade in/out, camera-iris adjustment, flicker, illumination change, and so on. In this scheme, a set of two brightness-variation parameters, which represent multiplier and offset components of the brightness-variation in the whole frame, is estimated. The brightness-variation is then compensated using the parameters. We also propose a method to apply the GBC scheme to component signals for video coding. Furthermore, a block-by-block on/off control method for GBC is introduced to improve the coding performance even for scenes including local variations in brightness caused by camera flashes, spotlights, and the like. Simulation results show that the proposed GBC scheme with the on/off control method improves the peak signal-to-noise ratio (PSNR) by 2-4 dB when the coded scenes contain brightness-variations
Keywords :
brightness; motion compensation; video coding; PSNR; brightness-variation parameters; camera flashes; camera-iris adjustment; coding efficiency; coding performance; component signals; fade in/out; flicker; global brightness-variation compensation; illumination change; motion compensation; multiplier component; offset component; on/off control method; peak signal-to-noise ratio; simulation results; spotlights; video coding; video scenes; Brightness; Cameras; Computational complexity; Layout; Lighting; Motion compensation; Motion detection; Motion estimation; Phase detection; Video coding;
Journal_Title :
Circuits and Systems for Video Technology, IEEE Transactions on
