Compensation for delay in PTZ camera system
AssigneeAvigilon Corporation
InventorShaun P. Marlatt
Life of this patent
Estimating the term…
Abstract
Compensating for delay in a Pan-Tilt-Zoom (PTZ) camera system is disclosed. Client-side view transformation is carried out to emulate a future Field Of View (FOV) of the camera so that the impact of latency is reduced.
Claims19
A method carried out on a computer terminal that includes a display and at least one input device, the computer terminal in communication with a Pan-Tilt-Zoom (PTZ) camera device over at least one network, and the method comprising:
- receiving user input provided through the input device;
- generating a command, specific to the user input, that defines a camera movement for making a change in a Field Of View (FOV) of the PTZ camera device;
- transmitting the command, destined to be received by the PTZ camera device and to effect eventual camera movement thereof, over the at least one network;
- in a period of time overlapping with the transmitting of the command, locally transforming video frames to emulate future video frames produced, post-command execution, by the PTZ camera device, wherein local transformation of the video frames is done without using the future video frames being emulated;
- displaying the locally transformed frames on the display of the computer terminal;
- and
- repeatedly checking frames, received at the computer terminal via the at least one network, until a determination is made that a newly received frame indicates that the local transforming of the video frames is no longer needed.
Apparatus comprising:
- a computer terminal configured to communicate with a Pan-Tilt-Zoom (PTZ) camera device over at least one network, the computer terminal including:
- at least one input device to receive input from a user of the computer terminal;
- communication circuitry configured to transmit a command, destined to be received by the PTZ camera device and to effect eventual camera movement thereof, over the at least one network;
- a processor configured to:
- generate the command, specific to the user input, that defines a camera movement for making a change in a Field Of View (FOV) of the PTZ camera device;
- in a period of time overlapping with transmission of the command by the communication circuitry, locally transform video frames to emulate future video frames produced, post-command execution, by the PTZ camera device, wherein the future video frames being emulated are not used in the local transforming of the video frames;
- and
- repeatedly check frames, received at the computer terminal via the at least one network, until a determination is made that a newly received frame indicates that the local transforming of the video frames is no longer needed;
- and
- a display configured to display the locally transformed frames.
A method carried out on a computer terminal that includes a display and at least one input device, the computer terminal in communication with at least two camera devices, including at least one Pan-Tilt-Zoom (PTZ) camera device, over at least one network, and the method comprising:
- receiving user input provided through the input device;
- determining that the user input specifies a command that defines a camera movement for changing a Field Of View (FOV) of the PTZ camera device from a current FOV to a future FOV, the future FOV including an FOV region not a part of the current FOV but covered by a current FOV of another of the at least two camera devices;
- emulating a future video frame corresponding to the future FOV of the PTZ camera device by mosaicking image data from the PTZ camera device with image data from the another of the at least two camera devices;
- and
- displaying the emulated future video frame on the display before any video frames corresponding to the future FOV as generated by the PTZ camera device, post-command execution, are available to the computer terminal.
Dependencies are inferred from the claim text.