Joint optical flow motion compensation and video compression using hybrid vector quantization

摘要: Summary form only given. We propose a video coding and delivery scheme which is geared towards low bit-rate real-time performance requirements. use hybrid vector quantization scheme, with finite state wavelet-based hierarchical lookup (FSWHVQ) for motion vectors, embeds the Horn Schunck optical flow algorithm in table-lookups, uses lattice (LVQ) prediction errors. This both fast (table-lookups) accurate (dense field), avoids blocking artifacts poor plagues block schemes at bit rates. For restricted image compression/transmission scenarios like teleconferencing, good training set may be available, FSWHVQ viewed as storing an internal representation its tables, valid complete model of problem domain. Two row-wise lookups quantize pixel values to give two table indices, Y0 Y1, followed by column-wise second-level lookup, quantizes indices into one index, ZO. Schunck's method applies spatial temporal derivative masks, e.g., size 2/spl times/2, corresponding locations current previous images. These mask applications are embedded inside table-lookups. The field averages (u/sub av/,v/sub av/), frame, I/sub t-I/, together comprise "state", updated each frame. errors encoded LVQ, error vectors small (due flow-based estimation), but more randomly distributed. It possible handle large displacements, using computations on "smooth" bands DWT (discrete wavelet transform)