Silicon Imaging SI-2K, Руководство пользователя

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SiliconDVRSoftware
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SI 2K Manual
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RAM Buffer Indicator
The buffer space allocated in the CAM PREFS menu is used to buffer the in-
coming video. This buffer space is shown visually and numerically. When the
buffer is filled, the recording operation will stop. No data to that point will be
lost but no further data can be recorded until the buffer is emptied to disk.
The buffer gauge is an excellent troubleshooting tool. A slowly rising buffer indi-
cates that the CPU is not able to compress the incoming data at a fast enough
rate. A very rapidly filling buffer usually indicates that the disk system is not ac-
cepting data at a fast enough rate. This is typical for uncompressed mode.
RAM Buffer Overflow
The on-board RAM buffer prevents any dropped frames from occurring during
capture. Should disk speed in the case of Uncompressed 12-bit recording or
the processor speed in the case of CineForm RAW recording not be capable
of keeping up with the recording rate, eventually the RAM buffer will be con-
sumed, and recording must stop. When this occurs a message box appears
notifying the end-user that the RAM-buffer que is being written out to disk.
After the RAM buffer is flushed and the recorded contents are safely written to
disk, the live preview will resume. This functionality ensures that files are always
safely written out to disk, and with enough RAM also allows under-powered
machines to safely record in uncompressed 12-bit or high-resolution CineForm
RAW.
Remaining Disk Space
The amount of available disk space on the currently selected disk is shown.
The potential for problems recording increase as the disk reaches capacity.
Because a disk is a series of concentric circles rotating at a fixed speed, the
write speed slows as you reach inner tracks. Also, if the disk has been used a
number of times and has had individual files erased, the disk can become frag-
mented, again slowing the access rate.
Hot Spots on the Preview Screen
Hot spots are nine areas in an invisible tic-tac-toe pattern in the main viewing
screen. Each area either toggles a function on and off or sequences through a
series of options for that mode.
The basic layout is:
False Color Exposure Zone Meter
Zebra or pseudo-color is an exposure tool. Unlike the spot meter, which gives
you the exact exposure in a small area, zebra divides the exposure into ranges
and provide a visual indication for the entire image.
The meaning of each color is shown by the key in the metering area.