Image quality evaluation method, image quality evaluation system and image quality evaluation program

An image transmitting device that is applied for an image quality evaluation system for evaluating an image quality of a decoded image, said decoded image obtained by decoding an encoded image obtained by encoding an original image in a transmission destination, said image transmitting device comprising:

• encoded image transmitting unit for encoding and transmitting an inputted original image;
• feature quantity extracting unit for, from an image frame of said inputted original image, extracting a representative pixel component value indicative of a pixel component value that represents pixels within the above image frame, and pixel position information indicative of a pixel position in which said representative pixel component value appears as a feature quantity of said original image;
• feature quantity encoding unit for encoding the feature quantity of the original image extracted by said feature quantity extracting unit;
• and
• feature quantity transmitting unit for transmitting the feature quantity of the original image encoded by said feature quantity encoding unit to an image receiving device, being a transmission destination of said encoded image.

An image transmitting device that is applied for an image quality evaluation system for evaluating an image quality of a decoded image, said decoded image obtained by decoding an encoded image obtained by encoding an original image in a transmission destination, said image transmitting device comprising:

• encoded image transmitting unit for encoding and transmitting an inputted original image;
• feature quantity receiving unit for receiving information in which a representative pixel component value indicative of a pixel component value that represents pixels within the image frame of said decoded image, and pixel position information indicative of a pixel position in which said representative pixel component value appears have been encoded as a feature quantity of said decoded image;
• feature quantity decoding unit for decoding said encoded feature quantity of said decoded image received by the feature quantity receiving unit;
• and
• error estimating unit for, by employing the representative pixel component value and the pixel position information each of which is the feature quantity of said decoded image obtained by decoding, estimating a difference with said original image as a degree of image quality degradation of said decoded image based upon a difference between the pixel component value at the pixel position being indicated by said pixel position information, and said representative pixel component value within the image frame of said original image.

An image receiving device that is applied for an image quality evaluation system for evaluating an image quality of a decoded image, said decoded image obtained by decoding an encoded image obtained by encoding an original image in a transmission destination, said image receiving device comprising:

• encoded image receiving unit for receiving the encoded image obtained by encoding the original image;
• feature quantity receiving unit for receiving information in which a representative pixel component value indicative of a pixel component value that represents pixels within an image frame of said original image, and pixel position information indicative of a pixel position in which said representative pixel component value appears have been encoded as a feature quantity of said original image;
• feature quantity decoding unit for decoding said encoded feature quantity of said original image received by the feature quantity receiving unit;
• and
• error estimating unit for, by employing the representative pixel component value and the pixel position information each of which is the feature quantity of said original image obtained by decoding, estimating a difference with said original image as a degree of image quality degradation of said decoded image based upon a difference between the pixel component value at the pixel position being indicated by said pixel position information, and said representative pixel component value within the image frame of the decoded image obtained by decoding said encoded image.

An image receiving device that is applied for an image quality evaluation system for evaluating an image quality of a decoded image, said decoded image obtained by decoding an encoded image obtained by encoding an original image in a transmission destination, said image receiving device comprising:

• encoded image receiving unit for receiving the encoded image obtained by encoding the original image;
• feature quantity extracting unit for, upon receipt of said encoded image, from an image frame of the decoded image obtained by decoding said encoded image, extracting a representative pixel component value indicative of a pixel component value that represents pixels within above image frame, and pixel position information indicative of a pixel position in which said representative pixel component value appears as a feature quantity of said decoded image;
• feature quantity encoding unit for encoding the feature quantity of the decoded image extracted by said feature quantity extracting unit;
• and
• feature quantity transmitting unit for transmitting the feature quantity of the decoded image encoded by said feature quantity encoding unit to an image transmitting device, being a transmission source of said encoded image.