Page 771 - Cloud computing: From paradigm to operation
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Video processing and storage 4
5 Conventions
In this Recommendation:
– The keywords "is required to" indicate a requirement which must be strictly followed and from
which no deviation is permitted if conformance to this Recommendation is to be claimed.
– The keywords "is recommended" indicate a requirement which is recommended but which is not
absolutely required. Thus this requirement need not be present to claim conformance.
6 Scenarios
This clause describes typical scenarios illustrating the cloud computing platform supporting visual
surveillance and deriving its service requirements.
6.1 Video distribution
The cloud computing platform in a visual surveillance (VS) system can support large-scale real-time video
forwarding. For example, many surveillance cameras are deployed in the Great Wall Scenic Area, and the
remote monitoring function of the cameras is open to the public. If users wants to see current images of the
Great Wall remotely, they can view the network video information on their local devices through the cloud-
based real-time video distribution function.
Step 1: Users enter the customer unit (CU) which supports remote live video viewing of the Great Wall Scenic
Area, and submit their request to the VS system.
Step 2: After receiving a video-viewing request, the VS system authenticates the user information, and
obtains the related information from a video-forwarding function unit that is deployed on the cloud
computing platform. The cloud computing platform can dynamically create or destroy the video-forwarding
function according to current user requests. The VS system then responds to the CU with the information
about the video-forwarding function on the cloud computing platform.
Step 3: After receiving the VS system response, the CU sends a video-viewing request to the cloud computing
platform.
Step 4: The cloud computing platform obtains the video stream from the corresponding camera, and then
forwards the video stream to the CU.
6.2 Video transcoding
The cloud computing platform in a VS system can support video-transcoding functions, e.g., code rate
transformation and video format conversion. The traffic department of a city has deployed a large-scale VS
system in the city streets with high-definition network cameras. Users want to view the current traffic
situation on their way home with their mobile phones. Due to the limited bandwidth of mobile devices and
mobile data traffic limits, high-definition surveillance video needs to be transcoded to low-resolution video
before forwarding to the CU. The video-transcoding operation can be carried out on the cloud computing
platform.
Step 1: Users log into the VS system via their mobile customer unit (MCU), and select the appropriate network
camera. The MCU then sends a video-viewing request to the VS system with the video format description.
Step 2: After receiving the video-viewing request, the VS system authenticates the user information, and
obtains the related information from a video-forwarding function unit that is deployed on the cloud
computing platform. The VS system then responds to the MCU with the information from the video-
forwarding function in the cloud computing platform.
Step 3: After receiving the response of the VS system, the MCU sends a video-viewing request to the cloud
computing platform.
Step 4: The cloud computing platform obtains the video stream from the corresponding camera. Then,
according to the video format description of the MCU, the surveillance video stream is transcoded by the
video-transcoding component deployed in the cloud computing platform. The cloud computing platform can
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