System and methods to measure noise and to generate picture quality prediction from source having no reference
View Patent ↗Embodiments of the invention include a system and method to generate a quality rating prediction, such as MOS, of a video under test without using a second video as a reference. Instead of using a reference video, embodiments of the invention generate a pseudo reference video from measuring local impairments of the video under test. The local impairments are then accumulated to create a difference image. The difference image is then subtracted from the video under test to create the pseudo reference, to which the video under test is compared to generate the quality prediction rating. In some embodiments the local impairments may be measured by separating high frequency noise from the video under test from the video itself. Once separated, the noise is then measured and bandwidth compensated to generate the measured local impairments.
1. A method of generating a prediction of subjective picture quality from a single source of video input, comprising:
accepting one or more video frames at a single input;
aggregating a series of local impairments to produce a local impairment difference image for each of the one or more video frames including:
measuring impairments of at least a portion of a current video frame to obtain a measured amount;
adding the measured impairments to the current video frame to produce a video frame having added impairments; and
subtracting the video frame having the added impairments from the current video frame to produce the local impairment difference image;
combining the local impairment difference image with a respective frame of the originally accepted one or more video frames to create a pseudo reference; and
comparing the originally accepted one or more video frames with the pseudo reference to yield the prediction of subjective picture quality.
2. The method of generating a prediction of subjective picture quality from a single source of video input according to claim 1 in which measuring a series of local impairments comprises measuring noise within the one or more frames.
3. The method of generating a prediction of subjective picture quality from a single source of video input according to claim 1 in which measuring a series of local impairments comprises measuring impairments in a block of a current frame of the one or more video frames.
4. The method of generating a prediction of subjective picture quality from a single source of video input according to claim 3 further comprising measuring an impairment in one or more pixels of the current frame.
5. The method of generating a prediction of subjective picture quality from a single source of video input according to claim 1 in which the prediction of subjective picture quality is a Mean Opinion Score.
6. A method of generating a prediction of subjective picture quality from a single source of video input, comprising:
accepting one or more video frames at a single input;
measuring a series of local impairments within the one or more video frames;
aggregating the series of measured local impairments to produce a local impairment difference image for each of the one or more video frames including, in which aggregating the series of measured local impairments to produce a local impairment difference image comprises adding the measured series of local impairments to uniform video frame;
combining the local impairment difference image with a respective frame of the originally accepted one or more video frames to create a pseudo reference; and
comparing the accepted one or more video frames with the pseudo reference to yield the prediction of subjective picture quality.
7. A video measuring device, comprising:
a video input for accepting a video to test;
a local impairment measurer structured to measure one or more impairments within one or more video frames of the tested video;
an impairment generator structured to
produce a local impairment difference image from the measured local impairments by measured impairments of at least a portion of a current video frame to obtain a measured amount,
adding the measured amount of impairments to the current video frame to produce a video frame having the added impairments, and
subtracting the video frame having the added impairments from the current video frame; and
a pseudo reference video generator structured to produce a pseudo reference video from a combination of an output from the impairment generator and from the video to test.
8. The video measuring device of claim 7 further comprising a full-reference video quality predictor structured to accept the tested video and the pseudo reference video as inputs and to generate a prediction of subjective picture quality of the tested video.
9. The video measuring device of claim 8 in which the prediction of subjective picture quality includes a Mean Opinion Score.
10. The video measuring device of claim 7 in which the local impairment measurer is structured to measure at least one of noise, mosquito noise, ringing, blur, jerkiness, freeze frame, jaggies, and block effects of at least one frame of the tested video.