US 5,335,019 A · Digital video data quantization error detection as applied to intelligent dynamic companding

Abstract

Under one embodiment, a first and a second similarly constituted detector, and an OR gate coupled to the two detectors, are provided to a digital video system. The first detector detects quantization errors of numerically adjacent values in vertically adjacent pixels of a current frame. The second detector detects quantization errors of numerically adjacent values in horizontally adjacent pixels in the current frame. The OR gate is used to determine whether quantization errors of numerically adjacent values are detected in at least one of the two spatial dimensions of pixel adjacency in the current frame. In one variation of this embodiment, a potential quantization error lookup table that supports concurrent lookups for vertically and numerically adjacent quantization error detection as well as horizontally and numerically adjacent quantization error detection is used and shared between the two detectors. In an expanded embodiment, a third similarly constituted detector is further provided, and coupled to the OR gate. The third detector detects quantization errors of numerically adjacent values in temporally adjacent pixels of successive frames. The OR gate is used to determine whether quantization errors of numerically adjacent values are detected in at least one of the three dimensions of pixel adjacency. In a further expanded embodiment, a compensation corrector is further provided, and coupled to the OR gate. The compensation corrector prevents successive shifting/modifying of digital video data of horizontally/vertically/temporally adjacent pixels to the same value otherwise resulting from dynamic companding.

Claims38

Dependent claims

In a digital video system comprising a plurality of digitized lines of video, an apparatus for detecting quantization errors of numerically adjacent values of digital video data of adjacent pixels in a dimension of pixel adjacency, said apparatus comprising:

a) first condition determination means for determining whether digital video data of a first and a second line of video have identical pixel values, said first and second lines of video being synchronized in said dimension of pixel adjacency;
b) second condition determination means for determining whether corresponding digital video data of said first and second lines of video are members of a list of input values (data.sub.-- in) of a digital video data shifting/modifying function that cause quantization errors;
c) third condition determination means for determining whether corresponding digital video data of said first and second lines of video are numerically adjacent to each other;
and
d) fourth condition determination means coupled to said first, second and third condition determination means for determining if quantization errors of numerically adjacent values exist for corresponding digital video data of said first and second lines of video based on the determination results of said first, second and third condition determination means.

2 more elements

In a digital video system comprising a plurality of digitized lines of video, a method for detecting quantization errors of numerically adjacent values of digital video data of adjacent pixels in a dimension of pixel adjacency, said method comprising the steps of:

a) determining whether digital video data of a first and a second line of video have identical pixel values, said first and second lines of video being synchronized in said dimension of pixel adjacency;
b) determining whether corresponding digital video data of said first and second lines of video are members of a list of input values (data.sub.-- in) of a digital video data shifting/modifying function that cause quantization errors;
c) determining whether corresponding digital video data of said first and second lines of video are numerically adjacent to each other;
and
d) determining if quantization errors of numerically adjacent values exist for corresponding digital video data of said first and second lines of video based on the determination results of said steps a) through c).

2 more elements

In a digital video system comprising a plurality of digitized lines of video, an apparatus for detecting quantization errors of numerically adjacent values of digital video data of adjacent pixels in a first and a second dimension of pixel adjacency, said apparatus comprising:

a) first detection means for detecting quantization errors of numerically adjacent values of digital video data of a first and a second line of video in said first dimension of pixel adjacency, said first and second lines of video being synchronized in said first dimension of pixel adjacency;
b) second detection means for detecting quantization errors of numerically adjacent values of digital video data of said first and a third line of video in said second dimension of pixel adjacency, said first and third lines of video being synchronized in said second dimension of pixel adjacency;
and
c) third detection means coupled to said first and second detection means for detecting quantization errors of numerically adjacent values of corresponding digital video data of said first and second lines of video, and said first and third lines of video, based on the detection results of said first and second detection means.

1 more element

In a digital video system comprising a plurality of digitized lines of video, a method for detecting quantization errors of numerically adjacent values of digital video data of adjacent pixels in a first and a second dimension of pixel adjacency, said method comprising the steps of:

a) detecting quantization errors of numerically adjacent values of digital video data of a first and a second line of video in said first dimension of pixel adjacency, said first and second lines of video being synchronized in said first dimension of pixel adjacency;
b) detecting quantization errors of numerically adjacent values of digital video data of said first and a third line of video in said second dimension of pixel adjacency, said first and third lines of video being synchronized in said second dimension of pixel adjacency;
and
c) detecting quantization errors of numerically adjacent values of corresponding digital video data of said first and second lines of video, and said first and third lines of video, based on the detection results of said first and second detection means.

1 more element

Dependencies are inferred from the claim text.

Digital video data quantization error detection as applied to intelligent dynamic companding

Life of this patent

Digital video data quantization error detection as applied to intelligent dynamic companding

Life of this patent

Abstract

Claims38