Length detection of slant scratches
AssigneeBTS Holdings International B.V.
InventorGerhard Wischermann
Life of this patent
Estimating the term…
Abstract
A video signal-processing device, for example a film scanner, including an arrangement for detecting scratches in images of a video signal. To improve the detection of slant scratches, the arrangement for detecting scratches combines a given number (m) of series-arranged pixels (43, 44) of a video image to form a group (45), and to determine a division of the pixels in accordance with given criteria for each group of pixels and, based on this division, to classify the pixel groups in scratch sections and non-scratch sections.
Claims16
A video signal-processing device comprising an arrangement for detecting scratches in images of a video signal, characterized in that the arrangement for detecting scratches comprises:
- means for combining a given number (m) of series-arranged pixels of a video image to form a group;
- means for determining a division of the pixels in accordance with given criteria for each group of pixels;
- and
- means for classifying, based on this division, the pixel groups in scratch sections and non-scratch sections,
- further characterized in that, for the purpose of classification of scratch sections, the arrangement comprises:
- means for comparing high-pass-filtered pixels with at least a contrast threshold value (+C);
- means for determining a sum of the pixels of a pixel group exceeding a given contrast threshold value (+C);
- and
- means for classifying, in so far as this sum exceeds a further threshold value (m/2), this pixel group as a scratch section.
An arrangement for detecting scratches in images of a video signal, characterized in that the arrangement for detecting scratches comprises:
- means for combining a given number (m) of series-arranged pixels of a video image to form a group;
- means for determining a division of the pixels in accordance with given criteria for each group of pixels;
- and
- means for classifying, based on this division, the pixel groups in scratch sections and non-scratch sections,
- further characterized in that, for the purpose of classification of scratch sections, said arrangement for detecting scratches comprises:
- means for comparing high-pass-filtered pixels with at least a contrast threshold value (+C);
- means for determining a sum of the pixels of a pixel group exceeding a given contrast threshold value (+C);
- and
- means for classifying, in so far as this sum exceeds a further threshold value (m/2), this pixel group as a scratch section.
A video signal-processing device comprising an arrangement for detecting scratches in images of a video signal, characterized in that the arrangement for detecting scratches comprises:
- means for combining a given number (m) of series-arranged pixels from contiguous scan lines of a single uncombined video image to form a group;
- means for determining a division of the pixels in accordance with given criteria for each group of pixels;
- and
- means for classifying, based on this division, the pixel groups in scratch sections and non-scratch sections
- further characterized in that, for the purpose of classification of scratch sections, the arrangement comprises:
- means for comparing high-pass-filtered pixels with at least a contrast threshold value (+C);
- means for determining a sum of the pixels of a pixel group exceeding a given contrast threshold value (+C);
- and
- means for classifying, in so far as this sum exceeds a further threshold value (m/2), this pixel group as a scratch section.
A film scanner for scanning a film image and detecting scratches in the film image, the film scanner comprising:
- a scanning device for producing a single uncombined video image from the film image;
- a combining device for combining a given number (m) of series-arranged pixels from contiguous scan lines of the single uncombined video image to form a group;
- a scratch detector for determining a division of the pixels in accordance with given criteria for each group of pixels wherein the pixel groups are classified in scratch sections and non-scratch sections, wherein the scratch detector comprises:
- means for comparing high-pass-filtered pixels with at least a contrast threshold value (+C);
- means for determining asum of the pixels of a pixel group exceeding a given contrast threshold value (+C);
- and
- means for classifying, in so far as this sum exceeds a further threshold value (m/2), this pixel group as a scratch section.
Dependencies are inferred from the claim text.