Video picture component prediction method and apparatus, and computer storage medium

A picture component prediction method, applied to an encoder, the method comprising:

• determining a first picture component reference value set of a current block;
• determining multiple first picture component reference values according to the first picture component reference value set, wherein the multiple first picture component reference values include four reference values corresponding to four preset sample positions, respectively;
• performing first filtering processing on sample values of samples corresponding to the multiple first picture component reference values, respectively, to determine multiple filtered first picture reference sample values, wherein the first filtering processing is performed on the sample values of the samples corresponding to the multiple first picture component reference values to obtain a filtered reference value set, and wherein reference sample values in the filtered reference value set are compared, and wherein a set of greater first picture component reference values and a set of smaller first picture component reference values are determined based on the reference sample values, and wherein the multiple filtered first picture reference sample values are determined by using multiple values from each of the set of greater first picture component reference values and the set of smaller first picture component reference values;
• determining a parameter of a component linear model according to the multiple filtered first picture reference sample values and a corresponding to-be-predicted picture component reference values, the to-be-predicted picture component being a picture component which is different from the first picture component, and the component linear model characterizing a linear mapping relationship for mapping a sample value of the first picture component to a sample value of the to-be-predicted picture component;
• performing mapping processing on a reconstructed value of the first picture component of the current block according to the component linear model to obtain a mapped value;
• and
• determining a predicted value of the to-be-predicted picture component of the current block according to the mapped value.

A video component prediction device, applied to a decoder, the device comprising:

• a memory for storing executable video component prediction instructions;
• a processor for executing the executable video component prediction instructions stored in the memory to perform operations of:
• determining a first picture component reference value set of a current block;
• determining multiple first picture component reference values according to the first picture component reference value set, wherein the multiple first picture component reference values include four reference values corresponding to four preset sample positions, respectively;
• performing first filtering processing on sample values of samples corresponding to the multiple first picture component reference values, respectively, to determine multiple filtered first picture reference sample values, wherein the first filtering processing is performed on the sample values of the samples corresponding to the multiple first picture component reference values to obtain a filtered reference value set, and wherein reference sample values in the filtered reference value set are compared, and wherein a set of greater first picture component reference values and a set of smaller first picture component reference values are determined based on the reference sample values, and wherein the multiple filtered first picture reference sample values are determined by using multiple values from each of the set of greater first picture component reference values and the set of smaller first picture component reference values;
• determining a parameter of a component linear model according to the multiple filtered first picture reference sample values and a corresponding to-be-predicted picture component reference values, the to-be-predicted picture component being a picture component which is different from the first picture component, and the component linear model characterizing a linear mapping relationship for mapping a sample value of the first picture component to a sample value of the to-be-predicted picture component;
• performing mapping processing on a reconstructed value of the first picture component of the current block according to the component linear model to obtain a mapped value;
• and
• determining a predicted value of the to-be-predicted picture component of the current block according to the mapped value.

A video component prediction device, applied to a decoder, the device comprising:

• a memory for storing executable video component prediction instructions;
• a processor for executing the executable video component prediction instructions stored in the memory to perform operations of:
• determining a first picture component reference value set of a current block;
• determining multiple first picture component reference values according to the first picture component reference value set, wherein the multiple first picture component reference values include four reference values corresponding to four preset sample positions, respectively;
• performing first filtering processing on sample values of samples corresponding to the multiple first picture component reference values, respectively, to determine multiple filtered first picture reference sample values, wherein the first filtering processing is performed on the sample values of the samples corresponding to the multiple first picture component reference values to obtain a filtered reference value set, and wherein reference sample values in the filtered reference value set are compared, and wherein a set of greater first picture component reference values and a set of smaller first picture component reference values are determined based on the reference sample values, and wherein the multiple filtered first picture reference sample values are determined by using multiple values from each of the set of greater first picture component reference values and the set of smaller first picture component reference values;
• determining a parameter of a component linear model according to the multiple filtered first picture reference sample values and a corresponding to-be-predicted picture component reference values, the to-be-predicted picture component being a picture component which is different from the first picture component, and the component linear model characterizing a linear mapping relationship for mapping a sample value of the first picture component to a sample value of the to-be-predicted picture component;
• performing mapping processing on a reconstructed value of the first picture component of the current block according to the component linear model to obtain a mapped value;
• and
• determining a predicted value of the to-be-predicted picture component of the current block according to the mapped value.