Trellis quantization

This article includes a list of references, related reading, or external links, but its sources remain unclear because it lacks inline citations. Please help improve this article by introducing more precise citations. (June 2016) (Learn how and when to remove this message)

Trellis quantization is an algorithm that can improve data compression in DCT-based encoding methods. It is used to optimize residual DCT coefficients after motion estimation in lossy video compression encoders such as Xvid and x264. Trellis quantization reduces the size of some DCT coefficients while recovering others to take their place. This process can increase quality because coefficients chosen by Trellis have the lowest rate-distortion ratio. Trellis quantization effectively finds the optimal quantization for each block to maximize the PSNR relative to bitrate. It has varying effectiveness depending on the input data and compression method.

• VirtualDub/Xvid guide mentioning Trellis quantization
• FFMPEGx option documentation
• Trellis explanation and pseudocode by the x264-author

This computer science article is a stub. You can help Wikipedia by expanding it.

• v
• t
• e