Apparatus and method for motion video encoding employing an adaptive quantizer
AssigneeInternational Business Machines Corporation
InventorsCesar A. Gonzales, Eric Viscito
Life of this patent
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Abstract
An apparatus and method for encoding of a video picture is disclosed. The video picture has a plurality of pictures. The pictures each have a plurality of macroblocks. The macroblocks each have a plurality of sub-blocks. The apparatus comprising a first module configured to generate a transform coefficient C.sub.ij for each of the sub-blocks of the macroblock. The apparatus further comprises a second module configured to variably quantize the transform coefficient by a scaling factor Q.sub.p based on the complexity of the picture and any rate control requirements.
Claims10
A video encoding apparatus configured to convert groups of blocks of digital video signals into compressible groups of blocks of digital video signals, comprising:
- (a) a transform coefficient device, having an input configured to receive a digital video signal representing a block of a video image, configured to generate a first signal representing a set of transform coefficients C.sub.ij in response to said received digital video signal;
- (b) an adaptive quantization device, having an input coupled to said transform coefficient device, configured to receive said first signal representing a set of transform coefficients C.sub.ij, and to provide a second signal representing a quantized transform coefficient Cq.sub.ij in response to said first signal representing said set of transform coefficients C.sub.ij ;
- (c) a variable length coder, having an input coupled to said adaptive quantization device, configured to receive said second signal representing said quantized transform coefficient Cq.sub.ij and to provide a variable-rate signal having a variable bit rate and representing a compressed digital video signal in response to said second signal representing said quantized transform coefficient Cq.sub.ij ;
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- (d) a buffer, having an input coupled to said variable length coder, configured to equalize said variable bit rate of said variable-rate signal representing a compressed digital video signal and to provide a constant rate compressed digital video signal, and further configured to provide a third signal indicating buffer fullness.
A video encoding apparatus configured to convert groups of blocks of digital video signals into compressible groups of blocks of digital video signals, comprising:
- (a) a transform coefficient device, having an input configured to receive a digital video signal representing a block of a video image, configured to generate a first signal representing a set of transform coefficients C.sub.ij in response to said received digital video signal;
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- (b) an adaptive quantization device, having an input coupled to said transform coefficient device, configured to receive said first signal representing a set of transform coefficients C.sub.ij, and to provide a second signal representing a quantized transform coefficient Cq.sub.ij in response to said first signal representing said set of transform coefficients C.sub.ij, wherein said adaptive quantization device comprises:
- (1) a first multiplier configured to provide a third signal representing partially quantized video data CW.sub.ij in response to said first signal representing a set of transform coefficients C.sub.ij ;
- (2) a q.sub.p selection device, coupled to said first multiplier, operable to provide a fourth signal representing a quantization factor q.sub.p in response to said third signal representing partially quantized video data C.sub.ij ;
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- (3) a second and third multiplier and an adder, configured to transform said third signal representing partially quantized video data C.sub.ij into said second signal representing said quantized transform coefficient Cq.sub.ij, based on said fourth signal representing said quantization factor q.sub.p.
Dependencies are inferred from the claim text.