Quantization/inverse quantization unit selectably accommodating multiple video encoding standards and including differential pulse code modulator
First Claim
1. A quantization/inverse quantization circuit having a differential pulse code modulator (DPCM) in a video coder-decoder (CODEC), comprising:
- an internal direct current (DC) processor which detects that a number `128` is converted to `255` in case of an inverse quantization of video CODEC standards H.261 and H.263 and then reconstructs an original number, or directly passes through other modes without any conversion, in order to quantize a discrete cosine transform (DCT) result in video CODEC standards JPEG, H.261, H.263, MPEG-1, and MPEG-2, to inverse quantize a differential pulse code modulation result or to inverse quantize again the quantized result;
a Booth coded additive circuit which generates an input value of 3 bits necessary to a multiplier in order to perform a 3-bit multiplication;
a Booth multiplier which actually performs a multiplication and a division in quantization/inverse quantization;
a mismatch control circuit which is needed in said video CODEC standard MPEG-2; and
a DPC path control circuit which obtains a difference between DC values of data blocks, and includes a selecting means for selecting an input according to a process mode.
1 Assignment
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Accused Products
Abstract
Disclosed is a quantization/inverse quantization circuit including a differential pulse code modulator (DPCM). Video CODEC standards (i.e., JPEG, H.261, H.263, MPEG-1, and MPEG-2) include various functions for an image compression and an image reconstruction. The conventional quantization/inverse quantization circuit has been designed to be fit for only one desired standard, so that the quantization/inverse quantization circuit used for one standard cannot be directly used for another standard. Accordingly, in relation to a difference between standards and required function therebetween in order to use the present invention in all video CODEC standards, the present invention discloses a quantization/inverse quantization circuit which can support all modes (i.e., a quantization mode in coding, an inverse quantization mode in decoding, and a reconstruction mode) by employing one quantization circuit as a quantization/inverse quantization circuit which can be used in all video CODEC standards.
60 Citations
4 Claims
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1. A quantization/inverse quantization circuit having a differential pulse code modulator (DPCM) in a video coder-decoder (CODEC), comprising:
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an internal direct current (DC) processor which detects that a number `128` is converted to `255` in case of an inverse quantization of video CODEC standards H.261 and H.263 and then reconstructs an original number, or directly passes through other modes without any conversion, in order to quantize a discrete cosine transform (DCT) result in video CODEC standards JPEG, H.261, H.263, MPEG-1, and MPEG-2, to inverse quantize a differential pulse code modulation result or to inverse quantize again the quantized result; a Booth coded additive circuit which generates an input value of 3 bits necessary to a multiplier in order to perform a 3-bit multiplication; a Booth multiplier which actually performs a multiplication and a division in quantization/inverse quantization; a mismatch control circuit which is needed in said video CODEC standard MPEG-2; and a DPC path control circuit which obtains a difference between DC values of data blocks, and includes a selecting means for selecting an input according to a process mode. - View Dependent Claims (2, 3, 4)
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Specification