Apparatus for concealing error in transform coding of a motion picture

Claim 1

An apparatus for concealing an error of a transform coding of a moving picture, said apparatus having coding means for error-correcting coding of image data and decoding means for decoding an error-correcting code created by said coding means, said decoding means comprising: first concealment means, for analyzing data according to a type of said data, said data being error-detected but not corrected by an error correction decoder in said decoding means, for replacing said data with zero when said data corresponds to data of a second frequency component, for replacing said data with data of a frequency component which is the same as a frequency component of a horizontally adjacent block when said data correspond to data of a third frequency component, and for replacing said data with data of a frequency component which is the same as a frequency component of a vertically adjacent block when said data correspond to data of a fourth frequency component; and second concealment means, connected to said first concealment means, for replacing reproduced pixel values of an error-occurred block with reproduced pixel values of a previous frame, in case said data being error-detected but not corrected is data of one of (A) a first frequency component and (B) an additional information.

Claim 2

An apparatus for concealing an error of a transform coding of a moving picture, said apparatus having coding means for error-correcting coding of image data and decoding means for decoding an error-correcting code created by said coding means, said decoding means comprising: first concealment means, for analyzing data according to a type of said data, said data being error-detected but not corrected by an error correction decoder in said decoding means, for replacing said data with zero when said data corresponds to data of a second frequency component, for replacing said data with data of a frequency component which is the same as a frequency component of a horizontally adjacent block when said data correspond to data of a third frequency component, and for replacing said data with data of a frequency component which is the same as a frequency component of a vertically adjacent block when said data correspond to data of a fourth frequency component; and second concealment means, connected to said first concealment means, for replacing reproduced pixel values of an error-occurred block with reproduced pixel values of a previous frame, in case said data being error-detected but not corrected is data of one of (A) a first frequency component and (B) an additional information.

Claim 6

An apparatus for concealing an error of a transform coding of a digitized moving picture, said apparatus having coding means for treating one field or one frame of said digitized moving picture as one screen, dividing data of one screen into a plurality of blocks, deriving a transform coefficient by orthogonally transforming image data contained in each block, quantizing the transform coefficient of each block with predetermined number of bits, error-correction-coding a quantized index together with an additional information indicating a number of bits in each quantized index, said apparatus further having decoding means for decoding a code created by said coding means, said decoding means comprising: first concealment means for analyzing data according to a type of said data, said data being error-detected but not corrected by an error-correction decoder in said decoding means, for outputting a specific signal when said data is one of (A) data of a first frequency component and (B) data of said additional information, for replacing said data with zero when said data is data of a second frequency component, for replacing said data with data of the same frequency component from a horizontally adjacent block, when said data is data of a third frequency component, arid for replacing said data with data of the same frequency component from a vertically adjacent block when said data is data of a fourth frequency component; and second concealment means, connected to said first concealment means, for replacing reproduced pixel values of an error-occurred block with reproduced pixel values of a previous frame according to said signal output from said first concealment means, in the event that said data being error-detected but not corrected is one of (A) data of said first frequency component and (B) data of an additional information.

Claim 7

An apparatus for concealing an error of a transform coding of a digitized moving picture, said apparatus having coding means for treating one field or one frame of said digitized moving picture as one screen, dividing data of one screen into a plurality of blocks, deriving a transform coefficient by orthogonally transforming image data contained in each block, quantizing the transform coefficient of each block with predetermined number of bits, error-correction-coding a quantized index together with an additional information indicating a number of bits in each quantized index, said apparatus further having decoding means for decoding a code created by said coding means, said decoding means comprising: first concealment means for analyzing data according to a type of said data, said data being error-detected but not corrected by an error-correction decoder in said decoding means, for outputting a specific signal when said data is one of (A) data of a first frequency component and (B) data of said additional information, for replacing said data with zero when said data is data of a second frequency component, for replacing said data with data of the same frequency component from a horizontally adjacent block, when said data is data of a third frequency component, arid for replacing said data with data of the same frequency component from a vertically adjacent block when said data is data of a fourth frequency component; and second concealment means, connected to said first concealment means, for replacing reproduced pixel values of an error-occurred block with reproduced pixel values of a previous frame according to said signal output from said first concealment means, in the event that said data being error-detected but not corrected is one of (A) data of said first frequency component and (B) data of an additional information.

Claim 9

An apparatus for concealing an error of a transform coding of a digitized moving picture, comprising: coding means for treating one field or one frame of said digitized moving pictures as one screen, dividing data of one screen into a plurality of blocks, deriving a transform coefficient by orthogonally transforming image data contained in each block, quantizing index together with an additional information indicating a quantizing bit number; decoding means for decoding a code created by said coding means; and concealment means for analyzing data according to a type of said data, said data being error-detected but not corrected by an error correction decoder in said decoding means, for replacing said data with data of the same frequency component from a block at the same location of a previous frame when said data is data of a first frequency component, for replacing said data with zero when said data is data of a second frequency component, for replacing said data with data of the same frequency component from a horizontally adjacent block when said data is data of a third frequency component, and for replacing said data with data of the same frequency component from a vertically adjacent block when said data is data of a fourth frequency component.

Claim 10

An apparatus for concealing an error of a transform coding of a digitized moving picture, comprising: coding means for treating one field or one frame of said digitized moving pictures as one screen, dividing data of one screen into a plurality of blocks, deriving a transform coefficient by orthogonally transforming image data contained in each block, quantizing index together with an additional information indicating a quantizing bit number; decoding means for decoding a code created by said coding means; and concealment means for analyzing data according to a type of said data, said data being error-detected but not corrected by an error correction decoder in said decoding means, for replacing said data with data of the same frequency component from a block at the same location of a previous frame when said data is data of a first frequency component, for replacing said data with zero when said data is data of a second frequency component, for replacing said data with data of the same frequency component from a horizontally adjacent block when said data is data of a third frequency component, and for replacing said data with data of the same frequency component from a vertically adjacent block when said data is data of a fourth frequency component.