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Tip

The Video Camera Object

If the video If a camera supports multistreaming, you can select the quality of the video stream that you want to display in viewing tiles.

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titleNote

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the Surveillance window.

To select the video stream quality, do as follows:

  1. In the context menu of the viewing tileSurveillance window, select the the Select quality item.
  2. Select the quality of the video stream that you want for display in the viewing tileSurveillance window.

    Item

    Menu item

    Description

    Auto (GreenStream, default)

    The camera has two video streams: high quality video stream and low quality video stream. If the size of the cell where the video image from the camera is displayed is close to the low quality resolution with a 10% height or width margin, the video image will be displayed using the low quality stream. In other cases, the high quality video stream will be displayed.

    High quality

    A high quality video stream is used in the video surveillance window.

    Low quality

    A low-quality video stream is used in the video surveillance window. When you enlarge the surveillance window, the video stream switches to a high quality video stream.

    Info
    titleNote

    The automatic video stream selection (the Auto item) is unavailable, if automatic resolution selection is set for any stream.

    Algorithm for displaying a video stream in the Surveillance window if there are several streams in the camera (see Camera):

    1. a suitable video stream is selected using the following algorithm:
      1. determine the available space for video output on the layout;
      2. select the video streams for which the Use for GreenStream option is enabled (see Camera) and sort them in ascending order of the original video width;
      3. for each stream:
        • reduce the original height and width while maintaining the proportions so that the new height and width do not exceed the available space for video output on the layout;
        • if the size of the stream after inserting it into the output area does not exceed 110% of the original size, select this stream for further output.
    2. select the stream that has the highest frame rate among other suitable video streams of the same resolution;
    3. if several video streams were selected in the previous steps, select the video stream with the maximum bitrate among them.

    If a stream was selected based on the maximum bitrate, then another stream will be selected only if its bitrate is more than 5% higher than the current one (to eliminate frequent switching if the values are approximately equal).

    When changing the characteristics of video streams, the decision to change the stream to display is made only if the need for a change is confirmed within 35 seconds. This measure is also intended to eliminate frequent switching of video streams.

    When the Surveillance window is enlarged, it switches to a high-quality video stream.

    Info
    titleNote

    You can specify the GREEN_STREAM_SCALE_RATIO environment variable (see Creating system variable), which allows you to change the resolution depending on the required video stream quality.

    • To decrease the resolution (display a video stream of lower quality), set the value of the GREEN_STREAM_SCALE_RATIO variable greater than 1. For example: 1.25, 1.5, 2, or 3.
    • To improve the resolution (display a video stream of higher quality), set the value of the GREEN_STREAM_SCALE_RATIO variable less than 1. For example: 0.75, 0.5, or 0.25.

      Info
      titleNote

      You must select the values of the variable empirically.

    High quality

    Algorithm for displaying a high-quality video stream in the Surveillance window if there are several streams in the camera (see Camera):

    1. select the video streams for which the Use for GreenStream option is enabled (see Camera);
    2. among the selected video streams, select those that have the highest resolution;
    3. among the selected video streams with the highest resolution, select the one with the highest frame rate;
    4. if several video streams were selected in the previous steps, select the stream with the maximum bitrate among them

    Low quality

    Algorithm for displaying a low-quality video stream in the Surveillance window if there are several streams in the camera (see Camera):

    1. select the video streams for which the Use for GreenStream option is enabled (see Camera);
    2. among the selected video streams, select those that have the lowest resolution;

    3. among the selected video streams with the lowest resolution, select the one with the highest frame rate;

    4. if several video streams were selected in the previous steps, select the stream with the minimum bitrate among them

    Other

    You can select a specific video stream from a video camera to display in the Surveillance window

  3. Click in the area between Surveillance windowsClick in the area between the tiles.

Selection of the video stream quality in the viewing tile Surveillance window is complete.The Image Removed symbol in the video surveillance window indicates high quality stream.
Image Removed