The
Recording: Encode
menu allows you to alter and customize how the NVR records footage and
“encodes” the files. You can choose and alter:
•
the resolution (per channel),
•
the frame rate (how many images per second the NVR records), and
•
the data-rate of each video stream. The higher the data rate, the “better” your images will look,
but the more space they’ll require on your HDD.
Channel :
The channel feed
you want to alter the settings
for.
Stream Type:
Whether you’re
editing the parameters for the
mainstream or the sub-stream.
Main-Stream:
the video feed
that the NVR will record and
display. This is the higher-
quality stream.
Sub-Stream: t
he video stream
that the NVR will send to remote
devices via a network or the
Internet. It is the lower-quality
stream as a reduction in video
size makes it easier to send over a network.
Record Audio:
recording with Audio
Resolution:
How many “little dots” are going to make up your image.
Frame Rate:
The number of frames per second (fps) that the NVR will record. Reducing the number of
frames per second will
not
save hard drive space but potentially
will
improve the data-rate per frame.
Max. BitRate(Kbps):
The actual amount of data that the NVR will use to record video. The higher the
bitrate, the more space each recording will take up on the hard disk. Generally speaking, recordings
encoded at higher bitrates will be of better quality, especially when recording movement.
The main-stream uses a variable bitrate to record video - the more movement occurs in the video, the
higher the bitrate will have to be. When there’s little movement in view, the NVR will automatically reduce
the bitrate to conserve HDD space.
If the amount of movement in a recording would require a higher bitrate to accurately record than what
you’ve selected as the maximum, the NVR will attempt to preserve as much of the quality as possible by
applying compression to the image. This compression will take the form of irregular, fuzzy blocks over
segments or the entire image. If you encounter this, it indicates that you might need to increase the overall
bitrate.
If you’ve set a high bitrate but a low frame rate, the NVR will still use all the data it can, resulting in
potentially higher quality per frame than at higher frame rates.
The sub-stream uses a constant bit-rate to makes the video easier to stream over a network or the Internet.
Note
: Both the main-stream and the sub-stream are always operating - in fact, the sub-stream forms part of
the main- stream. The options will affect the output quality of each stream, but won’t change which one is
being used in different circumstances.
Recording -> Encode
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