User`s manual

7. Error messages
Barco – iStudio – R5976569 – user's manual – revision 09 – March-2007
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7-3
7.1.3 Video errors
The following errors related to analog, SDI or HD-SDI video sources may occur:
Video errors
Value
Description
Videoblack
0 – 255 bit
in steps of 1 bit
The video data will be checked during 100 fields. If the luminance pixel data of each
pixel of each field is lower than the Videoblack level, the error becomes active.
Only pixels of the active area of a video are taken into consideration. The level for
this error can be set by means of the Setup source dialog box on the Alarm tab.
Videowhite
0 – 255 bit
in steps of 1 bit
The video data will be checked during 100 fields. If the luminance pixel data of each
pixel of each field is higher than the Videowhite level, the error becomes active.
Only pixels of the active area of a video are taken into consideration. The level for
this error can be set by means of the Setup source dialog box on the Alarm tab.
Videofreeze
0 – 255 bit
in steps of 1 bit
The summation of luminance pixel data over 10 fields will be compared with the
summation of the next 10 fields. If the difference is smaller than the Videofreeze
level over 100 fields a freeze is detected and the error becomes active. The level for
this error must be set dependant of the noise of the video data. A freeze will be
never detected if the level is too low and the source is noisy. Also if the level is too
high, the freeze detection will always be active. The level for this error can be set
by means of the Setup source dialog box on the Alarm tab.
SDI Decoder Errors
Videoloss
The SDI input signals passes through a variable gain equalizing stage. The SDI input
incorporates a signal strength indicator indicating both the presence of a carrier and
the amount of equalization applied to the signal. If the equalization is too high (e.g.
cable too long) or if there is no carrier (e.g. incoming amplitude too low), this error
becomes active.
Videolock A videolock error is detected if
• there is no input data detected ( no data transition over 1μs)
• the incoming data signal and the PLL clock are not phase locked
• the system is locked to a harmonic
VideoTRS A time reference signal (TRS) error is detected if
• the TRS is missing
• the TRS is in the wrong location
• the TRS is different from the one expected
Analog Decoder Errors
Videoloss This error appears if there is no sync detected within 31 consecutive line periods.
Videolock
Active when the PLL of the decoder is not locked:
The HYDRA indicates a lock error when the incoming data signal and the PLL clock are
not phase locked.
Videohorlock
This error appears if the horizontal sync is not found within about one clock cycle of
the expected position for 32 consecutive lines. This indicates the stability of the
incoming video. Consumer VCR’s is an example of source that tends to set this error.
Videolumaoverflow Luminance AD converter overflow detection.
Videochromaoverflow Chrominance AD converter overflow detection.
Indicators for video related input
closedcaption Active, when a closed caption signal is provided with the video signal.
TT_loss Active, when there is no teletext provided with the video signal.
Table 7-3
Video errors processed by H
YDRA