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| | Discussion  Print Video Image Processing
Work Order
Video Problems encountered from crime scene
incidences solved by TREC's Forensic Video Image Analysis
 | Quad camera scenes per single video frame which
preclude full camera views, instead of each quadrant optical quality digitally magnified
to a full frame;
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| Perpetrator too small to identify or too distant from
the camera, instead of optical quality digital magnification of the area of interest
times two X2, times four X4 and even times eight X8 (a TRECWare solution of the
classical problem of aliasing, stair stepping diagonals, curves or blockiness in digital
enlargement times two or larger);
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| Motion blur due to perpetrator running through the field of view, instead of splitting the blurred frame into separate fields which almost by definition have no motion blur, then optical quality
vertical magnification of either field into a full non motion blur frame (a TRECWare solution to this classical problem);
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| Image blur from lens poorly focused or coated
with dirt, dust, and grime, instead of user adjustable resolution enhancement to reduce or
eliminate blur;
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| Poor alphanumeric legibility, e.g., license
plate, logos, patches, etc., instead of user adjustable resolution enhancement for
improved sharpness with less blur;
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| Corrupted video fields or frames from rarely
maintained or seldom serviced VCR’s;
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| Field recorded time lapse video viewed on frame
display monitors, images seconds apart interlaced confusing;
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| Ghost perpetrators within frames, i.e., recorded
in one field only, with fields seconds apart, the resulting frame having the
perpetrator in every other line and difficult to identify; instead of splitting the frame
into separate fields then optical quality vertical magnification of the field of
interest into a full frame;
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| Wavy distortion, video tear, poor sync signals,
or time base distortion, rolling unstable images, instead of splitting the blurred
images into fields having no blur then optical quality vertical magnification into a
stable frame;
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| Lack of intensity and contrast due to over used
or poor quality video tape, worn out magnetic media, instead of intensity
adjusted contrast and brightness in linear and non-linear modes;
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| Dark noisy environments, low light levels, poorly
lit perpetrators, black on black, instead of frequency sensitive user selectable digital
noise filters with no noticeable loss of image detail and non-linear intensity adjustment
for seeing into black on black areas of interest;
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| Incorrect or no azimuth on playback VCR’s
for azimuth recorded VCR tapes resulting in overlapped noisy images, inserted of user
selectable azimuth selection on playback VCR's;
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| Blocky/blurry enlargement of the areas of
interest by the computer at X2, X4, or X8 magnification, produced by classical
image analysis techniques, instead of optical quality digital magnification enlarging
areas of interest by the computer at X2, X4, or X8 magnification;
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| Video tape sections edited, cut, merged, erased,
or tampered with in any fashion;
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| Difficult tape authenticity proof, is it a copy
or an original, instead of clearly defined/displayed field switch points, where possible;
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| Difficult courtroom video environments for
counsel, judges, and juries, poor equipment, small screen monitors, tape controller timeout
blackouts, instead of a large screen 32" monitor for the jury, high resolution
monitors for the judge and opposing counsel all with time base correction, wide
band path distribution and manual advance/backup of selected enhanced/crime scene images;
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| Low resolution laser jet hardcopy, e.g., 600 dpi
(dots per inch half tone) equivalent to 37.5 lpi (lines per inch screen frequency continuous tone) for 256 shades of
gray or 1200 dpi with 75 lpi producing blockiness, blotchy areas, stair stepping diagonal lines, jaggedness, half tone
printing; instead of glossy photographic quality 300 lpi continuous tone line screen dye sublimation prints with 256
shades of gray;
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| Computer Monitor VGA (Video Graphics Adapters)
gray scale images with only 64 shades of gray, instead of 256 shades, {VGA/SVGA Adapters
have upwards to millions of colors but only 64 shades of any one color, i.e., gray. This
is due to the six bit DAC's, digital to analogue converters, used in most VGA adapter
cards.
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Print Video Image Processing Work Order
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