Video signal coding systems and processes using adaptive quantization

An adaptive quantization method in a coding process for coding data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from a group of a plurality of quantizer sets R0-Rn, wherein each quantizer set differs from each other quantizer set in the group,
• the selecting step including the steps of
• determining and quantifying the distortion and bit rate characteristics provided by each quantizer set in the group R0-Rn for each portion of the video frame being coded;
• calculating an error value for each quantizer set in the group R0-Rn according to the formula:
• E=D+λr, where D is a quantified distortion value, r is a quantified bit rate value and λ is a weighting value selected based on the desired effect of r on the overall E;
• selecting the quantizer set Rx that exhibits the lowest E value of the quantizer sets within the group R0-Rn;
• and
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of values corresponding to the pel data value;
• the correlating step including the steps of
• determining the distortion and bit rate characteristics provided by each quantizer value in the selected quantizer set Rx;
• and
• selecting the quantizer value based on the distortion and bit rate characteristics provided by each quantizer value in the set Rx.

An adaptive quantization method in a coding process for coding data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from the group consisting of:
• R0={0,±3QP,±5QP,±7QP, . . . ,±255QP};
• R1={0,±3QP,±6QP,±7QP, . . . ,±255QP};
• R2={0,±3QP,±4QP,±7QP, . . . ,±255QP};
• R3={0,±2QP,±6QP,±7QP, . . . ,±255QP};
• R4={0,±2QP,±5QP,±7QP, . . . ,±255QP};
• R5={0,±2QP,±4QP,±7QP, . . . ,±255QP};
• R6={0,±2QP,±3QP,±7QP, . . . ,±255QP};
• R7={0,±4QP,±6QP,±7QP, . . . ,±255QP};
• R8={0,±4QP,±5QP,±7QP, . . . ,±255QP};
• R9={0,±1QP,±6QP,±7QP, . . . ,±255QP};
• R10={0,±1QP,±5QP,±7QP, . . . ,±255QP};
• R11={0,±1QP,±4QP,±7QP, . . . ,±255QP};
• R12={0,±1QP,±3QP,±7QP, . . . ,±255QP};
• R13={0,±1QP,±2QP,±7QP, . . . ,±255QP};
• R14={0,±5QP,±6QP,±7QP, . . . ,±255QP};
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of valucs corresponding to the pel data values.

An adaptive quantization method in a coding process for coding, data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from the group consisting of:
• R0={0,±3QP,±5QP,±7QP, . . . ,±255QP};
• R3={0,±2QP,±6QP,±7QP, . . . ,±255QP};
• R7={0,±4QP,±6QP,±7QP, . . . ,±255QP};
• R14={0,±5QP,±6QP,±7QP, . . . ,±255QP};
• and
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of values corresponding to the pel data values.

A system for coding sampled video data corresponding to at least a portion of a video frame, comprising:

• a storage means for storing a group of quantizer sets R0-Rn of quantizer values;
• means for selecting, for each video frame being coded, a quantizer set Rx from the group of quantizer sets R0-Rn, dependent on the quantified distortion and the bit rate of the selected set Rx;
• said selecting means further including
• means for calculating an error value E for each portion of the video frame being coded and for each quantizer set in the group R0-Rx, according to the formula:
• E=D+λr, where D is a quantified distortion value, r is a quantified bit ate value and λ is a weighting value selected based on the desired effect of r on the overall E;
• and
• means for selecting the quantizer Rx that exhibits the lowest E value of the quantizer sets within the group R0-Rn;
• means for correlating each video signal value for each frame portion being coded with a quantizer value from the set Rx selected for that frame portion;
• said means for correlating further including
• means for determining and quantifying the distortion and bit rate characteristics of each quantizer value within the set Rx;
• and
• means for selecting the quantizer value based on the distortion and bit rate characteristics provided by each quantizer value in the set Rx;
• and
• means for encoding the correlating quantizer values with a variable length encoding scheme.

An adaptive quantization method in a coding process for coding data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from a group of a plurality of quantizer sets R0-Rn, where each quantizer set differs from each other quantizer set in the group, and the quantizer sets are selected from the group consisting of:
• R0={0,±3QP,±5QP,±7QP, . . . ,±255QP};
• R1={0,±3QP,±6QP,±7QP, . . . ,±255QP};
• R2={0,±3QP,±4QP,±7QP, . . . ,±255QP};
• R3={0,±2QP,±6QP,±7QP, . . . ,±255QP};
• R4={0,±2QP,±5QP,±7QP, . . . ,±255QP};
• R5={0,±2QP,±4QP,±7QP, . . . ,±255QP};
• R6={0,±2QP,±3QP,±7QP, . . . ,±255QP};
• R7={0,±4QP,±6QP,±7QP, . . . ,±255QP};
• R8={0,±4QP,±5QP,±7QP, . . . ,±255QP};
• R9={0,±1QP,±6QP,±7QP, . . . ,±255QP};
• R10={0,±1QP,±5QP,±5QP, . . . ,±255QP};
• R11={0,±1QP,±5QP,±4QP, . . . ,±255QP};
• R12={0,±1QP,±5QP,±3QP, . . . ,±255QP};
• R13={0,±1QP,±5QP,±2QP, . . . ,±255QP};
• and
• R14={0,±5QP,±5QP,±6QP, . . . ,±255QP};
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of values corresponding to the pel data values.

An adaptive quantization method in a coding process for coding data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from a group of a plurality of quantizer sets R0-Rn, where each quantizer set differs from each other quantizer set in the group and the quantizer sets are selected from the group consisting of:
• R0={0,±3QP,±5QP,±7QP, . . . ,±255QP};
• R3={0,±2QP,±6QP,±7QP, . . . ,±255QP};
• R7={0,±4QP,±6QP,±7QP, . . . ,±255QP};
• and
• R14={0,±5QP,±6QP,±7QP, . . . ,±255QP};
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of values corresponding to the pel data values.

An adaptive quantization method in a coding process for coding data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from a group of a plurality of quantizer sets R0-Rn, wherein each quantizer set differs from each other quantizer set in the group, the step of selecting comprising the steps of:
• determining and quantifying the distortion and bit rate characteristics provided by each quantizer set in the group R0-Rn for each portion of the video frame being coded;
• calculating an error value E for each quantizer set in the group R0-Rn according to the formula:
• E=D+λr, where D is a quantified distortion value, r is quantified bit rate value and λ is a weighting value selected based on a desired effect of r on a total E;
• and
• selecting the quantizer set Rx having the lowest E value of the quantizer sets within the group R0-Rn;
• and
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of values corresponding to the pel data values, the step of correlating comprising the steps of:
• determining and quantifying the distortion and bit rate characteristics provided by each quantizer value in the selected quantizer set Rx;
• calculating an error value E′ for each pel and for each quantizer value in the set Rx according to the formula:
• E′=D′+λ′r′, where D′ is quantified distortion value, r′ is a quantified bit rate value and λ′ is a weighting value selected based on the desired effect of r′ on a total E′;
• selecting the quantize value having the lowest E′ value of the quantizer values with the set Rx.

An adaptive quantization method in a coding process for coding data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from a group of quantizer sets R0-Rn, wherein each quantizer value in each quantizer set is a multiple of a quantization coefficient QP and each quantizer set has a different combination of two quantizer values from a set of values consisting of:
• {═1QP,±2QP,±3QP,±4QP,±5QP,±6QP};
• the selecting step including the steps of
• determining the distortion and bit rate characteristics provided by each quantizer set in the group R0-Rn;
• and
• selecting the quantizer set Rx based on the distortion and bit rate characteristics provided by each quantizer set in the group;
• and
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of values corresponding to the pel data values.

An adaptive quantization method in a coding process for coding data values corresponding to each picture element (pel) of a portion of a video frame, the method comprising the steps of:

• selecting, for each portion of a video frame, a quantizer set Rx of quantizer values from a group of quantizer sets R0-Rn, wherein each quantizer value in each quantizer set is a multiple of a quantization coefficient QP and each quantizer set differs from each other quantizer set in a range of quantizer values between 0 and ±7QP and each quantizer set is identical to each other quantizer set outside the range of quantizer values;
• the selecting step including the steps of
• determining the distortion and bit rate characteristics provided by each quantizer set in the group R0-Rn;
• and
• selecting the quantizer set Rx based on the distortion and bit rate characteristics provided by each quantizer set in the group;
• and
• correlating each data value with a quantizer value from the selected quantizer set Rx to provide a quantized set of values corresponding to the pel data values.