2. IEC 62676-5 Ed. 1.0
Video surveillance systems for use in security applications
Part 5: Data specifications & image quality performance for camera devices
IEC 62676-1-1:2013 System requirements – general
IEC 62676-1-2:2013 System requirements – Performance requirements for video transmission
IEC 62676-2-1:2013 Video transmission protocols – general requirements
IEC 62676-2-2:2013 Video transmission protocols – IP interoperability implementation based
on HTTP and REST services
IEC 62676-2-3:2013 Video transmission protocols – IP interoperability implementation based
on Web services
IEC 62676-3:2013 Analog and digital video interfaces
IEC 62676-2:2014 Application guidelines
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3. Standardization body
IEC, Technical Committee 79, Working Group 12
Alarm systems – video surveillance
27 member states, 42 members in committee with 15 camera experts of different
manufactuers and institutions.
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4. Intention
The problem that has led to standardization activities:
Data printed in data sheets is not meaningful or does not help in selecting the right camera
for an application because:
It does not list the procedures used to determine them
Image quality parameters are missing
Data is meaningless (e.g. 0 lux in light sensitivity)
Data for parameters are missing
Measuring methodes were not available or were not standardized
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8. Accomplish the goals
In order to reach a standardization, the standard contains:
Terms, definitions and abbreviations
A description of typical specification for video surveillance cameras
The description of the measurement methods for these specificatinos
Some annexes, which contain future methods and measurement procedures, but which still need to
be tested and further developed.
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16. OECF
From the values of an OECF chart, the following parameters can be determined:
Dynamic Range
Visual Dynamic range
Noise
SNR (S/R)
Sensitivity respectively minimum illumination
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19. OECF – TE269C
General procedure:
Minimum visible light illumination necessary, expressed in lux, to obtain specified contrast
of the video output level (expressed in %) at which an object can be recognized, while
producing no less than 25 fps (30 fps).
OECF chart in combination with ND filter.
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21. OECF – TE269C
General procedure:
OECF measurement can be used to determine the clipping point (upper side) and, together
with noise measurement, to determine the point where S/N=1 (lower side). The ratio
between both luminance’s is the dynamic range.
The luminance of each grey scale patch shall be measured accurately and used as input
for the calculations.
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22. OECF – TE269C
Light source:
At least 100.000 lux entering the camera
Luminance range shall be larger than the expected dynamic range of the camera
White standard light source, effectively spectrally neutral (daylight or tungsten illuminants
e.g. CIE standard daylight simulated illuminants such as D65 or D50).
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23. OECF – TE269C
Measurement procedure:
It is not needed that the test target is viewed by the camera at full scale, but make sure that
each grey scale patch should be sampled by at least 32x32=1024 pixels.
The camera lens should be focused on the test target, such that the image produced
appears reasonably sharp. The camera lens may be slightly defocused to blur high
frequency noise or halftone screening present in the test chart.
Camera exposure settings should be adjusted to produce at least 1 clipped grey scale
patch.
More clipped patches are allowed but try to keep that number low while it reduces the
usable dynamic range of the test target. Auto exposure may be used.
Capture a picture of the camera output for evaluation. Capturing more pictures, preferably
8, improves the reliability of the measurement.
Sample all grey scale patches with at least 32x32 pixels. Be sure to sample the
homogeneous part of each patch and avoid the edges.
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25. Visible Dynamic Range
General procedure:
Ratio between the maximum illumination which procedures unclipped detailed image (just
below saturation level) and the minimum illumination that can be output at 50% which is the
output bright enough to produce usable image.
OECF Chart as TE269C can be used.
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