Reducing undesirable effects of an emphasis processing operation performed on a moving image by adding a noise signal to a decoded uncompressed signal

A method for reducing undesirable effects of a filtering operation occurring after a decoding operation of a moving image represented by an encoded compressed signal, said filtering operation including an emphasis processing operation which causes improvement of some aspects of said moving image and also causes deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations, said method comprising the steps of:

• receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• detecting a flatness value of said decoded uncompressed signal representing how smoothly said luminance signal component changes;
• generating a random number;
• generating a noise signal as a function of said flatness value and said random number;
• adaptively combining said noise signal and said decoded uncompressed signal such that the undesirable effects of said emphasis processing operation are reduced;
• detecting a level of the combined decoded uncompressed signal and noise signal;
• and
• adjusting said level in accordance with a predetermined signal level.

A method for reducing undesirable effects of a filtering operation occurring after a decoding operation of a moving image represented by an encoded compressed signal, said filtering operation including an emphasis processing operation which causes improvement of some aspects of said moving image and also causes deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations, said method comprising the steps of:

• receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• receiving a quantization scale used during the encoding operation of said moving image;
• generating a random number;
• generating a noise signal as a function of said quantization scale and said random number;
• adaptively combining said noise signal and said decoded uncompressed signal such that the undesirable effects of said emphasis processing operation are reduced;
• detecting a level of the combined decoded uncompressed signal and noise signal;
• and
• adjusting said level in accordance with a predetermined signal level.

Apparatus for reducing undesirable effects of a filtering operation occurring after a decoding operation of a moving image represented by an encoded compressed signal, said filtering operation including an emphasis processing operation which causes improvement of some aspects of said moving image and also causes deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations, said apparatus comprising:

• means for receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• means for generating a random number;
• means for generating a noise signal as a function of said random number and luminance signal component;
• means for adaptively combining said noise signal and said decoded uncompressed signal such that the undesirable effects of said emphasis processing operation are reduced;
• means for detecting a level of the combined decoded uncompressed signal and noise signal;
• and
• means for adjusting said level in accordance with a predetermined signal level.

Apparatus for reducing undesirable effects of a filtering operation occurring after a decoding operation of a moving image represented by an encoded compressed signal, said filtering operation including an emphasis processing operation which causes improvement of some aspects of said moving image and also causes deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations, said apparatus comprising:

• means for receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• means for detecting a flatness value of said decoded uncompressed signal representing how smoothly said luminance signal component changes;
• means for generating a random number;
• means for generating a noise signal as a function of said random number and flatness value;
• means for adaptively combining said noise signal and said decoded uncompressed signal such that the undesirable effects of said emphasis processing operation are reduced;
• means for detecting a level of the combined decoded uncompressed signal and noise signal;
• and
• means for adjusting said level in accordance with a predetermined signal level.

Apparatus for reducing undesirable effects of a filtering operation occurring after a decoding operation of a moving image represented by an encoded compressed signal, said filtering operation including an emphasis processing operation which causes improvement of some aspects of said moving image and also causes deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations, said apparatus comprising:

• means for receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• means for receiving a quantization scale used during the encoding operation of said moving image;
• means for generating a random number;
• means for generating a noise signal as a function of said random number and quantization scale;
• and
• means for adaptively combining said noise signal and said decoded uncompressed signal such that the undesirable effects of said emphasis processing operation are reduced;
• means for detecting a level of the combined decoded uncompressed signal and noise signal;
• and
• means for adjusting said level in accordance with a predetermined signal level.

A television receiver for decoding an encoded compressed signal representing a moving image and for displaying said moving image, said television receiver comprising:

• means for receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• means for generating a random number;
• means for generating a noise signal as a function of said random number and luminance signal component;
• means for adaptively combining said noise signal and said decoded uncompressed signal;
• means for detecting a level of the combined decoded uncompressed signal and noise signal;
• means for adjusting said level in accordance with a predetermined signal level;
• means for emphasis processing said combined decoded uncompressed signal and noise signal to obtain an output signal, said emphasis processing means causing improvement of some aspects of said moving image and also causing deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations;
• and
• means for displaying said moving image represented by said output signal, wherein undesirable effects of said emphasis processing operation as viewed on said display means are reduced.

A television receiver for decoding an encoded compressed signal representing a moving image and for displaying said moving image, said television receiver comprising:

• means for receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• means for detecting a flatness value of said decoded uncompressed signal representing how smoothly said luminance signal component changes;
• means for generating a random number;
• means for generating a noise signal as a function of said flatness value and said random number;
• means for adaptively combining said noise signal and said decoded uncompressed signal;
• means for detecting a level of the combined decoded uncompressed signal and noise signal;
• means for adjusting said level in accordance with a predetermined signal level;
• means for emphasis processing said combined decoded uncompressed signal and noise signal to obtain an output signal, said emphasis processing means causing improvement of some aspects of said moving image and also causing deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations;
• and
• means for displaying said moving image represented by said output signal, wherein undesirable effects of said emphasis processing operation as viewed on said display means are reduced.

A television receiver for decoding an encoded compressed signal representing a moving image and for displaying said moving image, said television receiver comprising:

• means for receiving and decoding said encoded compressed signal to obtain a decoded uncompressed signal having at least a luminance signal component;
• means for receiving a quantization scale used during an encoding operation of said moving image;
• means for generating a random number;
• means for generating a noise signal as a function of said quantization scale and random number;
• means for adaptively combining said noise signal and said decoded uncompressed signal;
• means for detecting a level of the combined decoded uncompressed signal and noise signal;
• means for adjusting said level in accordance with a predetermined signal level;
• means for emphasis processing said combined decoded uncompressed signal and noise signal to obtain an output signal, said emphasis processing means causing improvement of some aspects of said moving image and also causing deterioration of other aspects of said moving image by unintentionally emphasizing signal encoding and compressing operations;
• and
• means for displaying said moving image represented by said output signal, wherein undesirable effects of said emphasis processing operation as viewed on said display means are reduced.