Methods, systems and apparatus for providing improved definition video

A method of filtering video images in a video display system comprising the steps of:

• generating video component level signals for pixels of images to be displayed as first and second fields of interlaced rows updated on alternate scans, the component level signals quantified by video component values represented as digital signals;
• detecting and replacing corrupted pixels in the first and second fields to produce filtered images using the video component values as represented by the digital signals, said step of detecting and replacing comprising the steps of:
• computing a global mean video component value from the video component values generated for a previous scan of at least one of the first and second fields;
• computing a global standard deviation from the global mean;
• computing a local mean video component value from the video component values generated for the plurality of pixels being updated as part of the current scan of the first field and neighboring a pixel in the first field being tested for corruption;
• computing the deviation from the local mean value of the video component value generated to update the pixel being tested as part of the current scan of the first field;
• characterizing the video component level of the pixel being tested as quantified the video component value generated to update the pixel being tested as part of the current scan of the first field if the deviation from the local mean is less than a selected multiple of the global standard deviation;
• comparing the deviation from the local mean of the video component value of the pixel being tested with a pre-selected threshold value if the deviation from the local mean value exceeds the selected multiple of the global standard deviation;
• quantifying the video component level of the pixel being tested in accordance with the video component value generated to update the pixel being tested as part of the current scan of the first field if the deviation from the local mean is less than the threshold value;
• and
• replacing the video component value generated to updated the pixel being tested as part of the current scan of the first field with a new video component value if the deviation from the local mean is greater than the threshold value;
• and
• displaying the filtered images using the digital signals video component values selected during said step of detecting and replacing.

A video system comprising:

• a video display operable to display images as a plurality of pixels each characterized by a video component level;
• circuitry for generating said video component levels formatted for the display of images as a plurality of pixels arranged in first and second fields of interlaced rows, updated on alternate scans;
• circuitry for quantifying said video component levels by numerical video component values represented by digital signals;
• and
• a processor for deinterlacing said pixels in said first and second fields of interlaced rows, said processor operable to:
• compute a global mean video component value from said video component values provided for a previous scan of at least one of the first and second fields;
• compute a global standard deviation from said global mean;
• compute a local mean video component value from said video component values provided for a current scan of said first field and forming a neighborhood of a said pixel in said second field being deinterlaced;
• compute a local standard deviation from said local mean video component value for said pixels in said first field forming said neighborhood of said pixel in said second field being deinterlaced;
• compare said local standard deviation with a preselected multiple of said global standard deviation;
• carry forward the video component value generated for said pixel being deinterlaced from a previous scan of said second field when said local standard deviation is less than said selected multiple of said global standard deviation and set said video component value for said pixel being deinterlaced to said local mean video component value when said local standard deviation exceeds said selected multiple of said global standard deviation;
• and
• generate, for display, the digital signals representing at least one of the carried forward and set video component values for said pixel being deinterlaced.

A video system comprising:

• a video display operable to display images as a plurality of pixels each characterized by a video component level;
• circuitry for generating said video component levels formatted for the display of images as a plurality of pixels arranged in first and second fields of interlaced rows, updated on alternate scans;
• circuitry for quantifying said video component levels by numerical video component values represented by digital signals;
• and
• a processor for detecting and replacing corrupted pixels in a said image to be displayed, said processor operable to:
• compute a global mean video component value from said video component values provided for a previous scan of at least one of said first and second fields;
• compute a global standard deviation from said global mean value;
• compute a local mean video component value from said video component values provided for a plurality of said pixels being updated as a part of a current scan of said first field and neighboring a said pixel in said first field being tested;
• compute the deviation from said local mean value of said video component value generated to update said pixel being tested as part of said current scan of said first field;
• compare the deviation from said local mean of said video component value of said pixel being tested with a selected multiple of said global standard deviation;
• characterize said video component value of said pixel being tested in accordance with said video component value generated to update said pixel being tested as part of said current scan of said first field if the deviation from said local mean is less than a selected multiple of said global standard deviation;
• compare the deviation from said local mean with a pre-selected threshold value if the deviation from said local mean value exceeds said pre-selected multiple of said global standard deviation;
• characterize said video component level of said pixel being tested in accordance with said video component value generated to update said pixel being tested as part of said current scan of said first field if the deviation from said local means is less than said threshold value;
• replace said video component value generated for said pixel being tested as part of said current scan of said first field with a new video component value if the deviation from said local mean is greater than said threshold value;
• and
• generate, for display, the digital signals representing at least one of the video component values generated to update the pixel being tested and replaced video component values generated for the pixel being tested.

A method for displaying images in a video display system, the method comprising the steps of:

• generating video component level signals for pixels of images to be displayed as first and second fields of interlaced rows updated on alternate scans, the component level signals quantified by video component values represented as digital signals;
• deinterlacing the pixels in the first and second fields to produce pixels for deinterlaced images using the video component values as represented by the digital signals, said step of deinterlacing comprising the steps of:
• computing global statistics characterizing the video component values generated for a previous scan of at least one of the first and second fields;
• computing local statistics characterizing the video component values generated for the plurality of pixels being updated as part of the current scan of the first field and defining a neighborhood of a pixel in the second field being deinterlaced;
• comparing the computed local statistics with the computed global statistics;
• and
• in response to said step of comparing, carrying forward the video component value generated as part of a previous scan of the second field for the pixel being deinterlaced when the video component values for the neighborhood as characterized by the local statistics do not differ from the video component values for the previous scan as characterized by the global statistics by a preselected amount and setting the video component value to a new value based on the local statistics when the video component values for the neighborhood as characterized by the local statistics differ from the video component values for the previous scan as characterized by the global statistics by the preselected amount;
• and
• displaying the deinterlaced images using the video component values selected during said step of deinterlacing.

A method of filtering video images in a video display system comprising the steps of:

• generating video component level signals for pixels of images to be displayed as first and second fields of interlaced rows updated on alternate scans, the component level signals quantified by video component values represented as digital signals;
• detecting and replacing corrupted pixels in the first and second fields to produce filtered images using the video component values as represented by the digital signals, said step of detecting and replacing comprising the steps of:
• computing global statistics characterizing the video component values generated for a previous scan of at least one of the first and second fields;
• computing local statistics from the video component values generated for a local plurality of pixels being updated as part of the current scan of the first field, the local statistics characterizing any difference between the video component value generated to update a pixel being tested and the video component values generated to update the local plurality of pixels;
• comparing the computed global statistics with the computed local statistics, and in response:
• quantifying the video component level of the pixel being tested in accordance with the video component value generated to update the pixel being tested as part of the current scan when the comparison indicates that any difference characterized by the local statistics does not vary from the values characterized by the global statistics by a preselected amount;
• replacing the video component value generated to update the pixel being tested as part of the current scan of the first field with a new video component value when the comparison indicates that any difference characterized by the local statistics varies from the values characterized by the global statistics by a preselected amount;
• and
• displaying the filtered images using the digital signals video component values selected during said step of detecting and replacing.