Method and apparatus for communicating video information in a communication system

• US 6,037,991 A
• Filed: 11/26/1996
• Issued: 03/14/2000
• Est. Priority Date: 11/26/1996
• Status: Expired due to Term

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Cizek, Paul J., Grube, Gary W., Thro, Stuart W.
• Primary Examiner(s): Peng, John K.
• Assistant Examiner(s): Sajous, Wesner
• Application Number:
  US08/756,852
• Time in Patent Office: 1,204 Days
• Field of Search: 348/7, 348/12, 348/13, 348/14, 348/15, 348/16, 348/17, 348/441, 348/443, 348/469, 348/384, 348/390, 348/397, 348/398, 348/399, 348/402, 348/407, 348/409, 348/413, 348/433, 348/415 , 348/416, 348/410, 348/411, 348/699, 455/5.1, 455/4.2, 455/404, 455/15, 370/465, 370/468, 370/412, 370/538
• US Class Current: 725/116
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/587 involving temporal sub-sampling or interpolation, e.g. decimation or subsequent interpolation of pictures in a video sequence
• CPC Class Codes: H04N 19/59 involving spatial sub-sampling or interpolation, e.g. alteration of picture size or resolution
• CPC Class Codes: H04N 7/147 Communication arrangements, e.g. identifying the communication as a video-communication, intermediate storage of the signals selecting H04Q
• CPC Class Codes: H04N 7/148 Interfacing a video terminal to a particular transmission medium, e.g. ISDN

Abstract

A communication system (100) employs a method and apparatus for communicating video information therein. A first communication device (e.g., 101) preferably includes a video compressor (203), a memory device (205) containing a computer program, and a modem (207). The first device receives video information from a video device (116) via the video compressor and executes the computer program to determine a priority between transmission frame rate and resolution per frame. When transmission frame rate is of higher priority, the first device transmits the video information at a first transmission frame rate via the modem to a second communication device (e.g., 102). When resolution per frame is of higher priority, the first device transmits the video information at a second transmission frame rate that is less than the first rate. The second device, upon receiving the video information, may display (113) the information or process the information for retransmission (e.g., when the second device is a video control server (104)).

Claims

1. A method for providing video information from a first communication device to a second communication device, the method comprising the steps of:

receiving video information from a video device coupled to the first communication device;

determining a priority between transmission frame rate and resolution per frame;

when transmission frame rate is of a higher priority than resolution per frame, transmitting the video information at a first transmission frame rate via a communication resource; and

when resolution per frame is of a higher priority than transmission frame rate, transmitting the video information at a second transmission frame rate via the communication resource, wherein the second transmission frame rate is less than the first transmission frame rate.

2. The method of claim 1, wherein the step of determining a priority comprises the step of automatically determining, by the first communication device, the priority between transmission frame rate and resolution per frame based on movement of the first communication device.

3. The method of claim 1, wherein the step of determining a priority comprises the step of manually determining, by a user of the first communication device, the priority between transmission frame rate and resolution per frame.

4. The method of claim 1, wherein the step of determining a priority comprises the steps of:

manually determining, by a user of the second communication device, the priority between transmission frame rate and resolution per frame; and

communicating, by the second communication device, the priority to the first communication device.

5. The method of claim 1, wherein the step of determining a priority comprises the steps of:

automatically determining, by the second communication device, the priority between transmission frame rate and resolution per frame based on a location of the first communication device; and

communicating, by the second communication device, the priority to the first communication device.

6. The method of claim 5, wherein the step of automatically determining comprises the step of automatically determining the priority between transmission frame rate and resolution per frame based on the location of the first communication device with respect to an intended destination of the first communication device.

7. The method of claim 1, wherein the step of determining a priority comprises the steps of:

determining circumstantial conditions at a location of the first communication device; and

selecting the priority based on the circumstantial conditions.

8. The method of claim 1, wherein the step of receiving comprises the steps of:

selecting a video device of a plurality of video devices coupled to the first communication device to produce a selected video device; and

receiving the video information from the selected video device.

9. The method of claim 8, wherein the step of selecting a video device comprises the steps of:

determining circumstantial conditions at a location of the first communication device; and

selecting the video device based on the circumstantial conditions.

10. The method of claim 1, wherein the step of receiving comprises the steps of:

selecting a first video device of a plurality of video devices coupled to the first communication device to produce a first selected video device;

selecting at least a second video device of the plurality of video devices coupled to the first communication device to produce at least a second selected video device; and

intermittently receiving video information from the first selected video device and the at least a second selected video device to produce the video information.

11. The method of claim 1, further comprising the steps of:

selecting, by the second communication device, a video device of a plurality of video devices coupled to the first communication device to produce a selected video device; and

communicating, by the second communication device, an identification of the selected video device to the first communication device,

and wherein the step of receiving the video information comprises the step of receiving the video information from the selected video device.

12. The method of claim 1, wherein the second communication device comprises a dispatch operator position.

13. The method of claim 1, wherein the second communication device comprises a video control server.

14. A method for a first communication device to provide video information to a second communication device, the method comprising the steps of:

selecting a first video device of a plurality of video devices coupled to the first communication device to produce a first selected video device;

selecting a second video device of the plurality of video devices coupled to the first communication device to produce a second selected video device;

receiving video information from the first selected video device to produce first video information;

receiving video information from the second selected video device to produce second video information;

selecting a first transmission frame rate for the first video information based on a priority between transmission frame rate and resolution per frame;

selecting a second transmission frame rate for the second video information based on the first transmission rate; and

transmitting the first video information at the first transmission frame rate and the second video information at the second transmission frame rate via a single communication resource.

15. A method for a video control server to provide video information to at least one communication device, the method comprising the steps of:

receiving, from a first communication device, first video information at a first transmission frame rate via a first communication resource, the first transmission frame rate corresponding to a first resolution per frame;

receiving, from a second communication device, second video information at a second transmission frame rate via a second communication resource, the second transmission frame rate corresponding to a second resolution per frame;

combining the first video information and the second video information to produce third video information; and

transmitting the third video information at a third transmission frame rate to the at least one communication device, the third transmission frame rate corresponding to a third resolution per frame.

16. A method for a video control server to provide video information to at least one communication device, the method comprising the steps of:

receiving, from a communication device of the at least one communication device, video information at a first transmission frame rate via a first communication resource;

converting the first transmission frame rate to a second transmission frame rate that is less than the first transmission frame rate, wherein at least some of the conversion is achieved by discarding a part of the video information; and

transmitting the video information at the second transmission frame rate to the at least one communication device via a second communication resource.

17. A method for a first communication device to obtain video information from a second communication device, the method comprising the steps of:

determining a priority between transmission frame rate and resolution per frame;

when transmission frame rate is of a higher priority than resolution per frame, receiving the video information at a first transmission frame rate via a communication resource; and

when resolution per frame is of a higher priority than transmission frame rate, receiving the video information at a second transmission frame rate via the communication resource, wherein the second transmission frame rate is less than the first transmission frame rate.

18. The method of claim 17, further comprising the step of:

prior to either step of receiving the video information, communicating the priority to the second communication device.

19. The method of claim 18, wherein the step of determining a priority comprises the steps of:

determining circumstantial conditions at a location of the second communication device; and

selecting the priority based on the circumstantial conditions.

20. The method of claim 18, wherein the step of determining a priority comprises the steps of:

determining whether the second communication device is in motion; and

when the second communication device is in motion, selecting transmission frame rate to have a higher priority than resolution per frame.

21. The method of claim 17, further comprising the steps of:

selecting a video device of a plurality of video devices coupled to the second communication device to produce a selected video device; and

communicating an identification of the selected video device to the first communication device, such that the selected video device is a source of the video information.

22. The method of claim 21, wherein the step of selecting a video device comprises the steps of:

determining circumstantial conditions at a location of the second communication device; and

selecting the video device based on the circumstantial conditions.

23. A communication device for transmitting video information, the communication device comprising:

a video compressor having an input to receive digitized video information from a video device and an output to provide a compressed video output signal;

a memory device having stored therein a computer program that, when executed, performs the following functions;

determines a priority between transmission frame rate and resolution per frame;

selects a first transmission frame rate to produce a selected transmission frame rate when transmission frame rate is of a higher priority than resolution per frame; and

selects a second transmission frame rate to produce the selected transmission frame rate when resolution per frame is of a higher priority than transmission frame rate, wherein the second transmission frame rate is less than the first transmission frame rate; and

a radio frequency modem having a first input coupled to the output of the video compressor, a second input coupled to the memory device, and an output to transmit the compressed video output signal at the selected transmission frame rate via a radio communication resource.

24. The communication device of claim 23, further comprising an analog-to-digital converter having an input coupled to receive analog video information from the video device and an output coupled to the input of the video compressor.

25. The communication device of claim 24, wherein the analog video information comprises a National Television Standards Committee (NTSC) format.

26. The communication device of claim 23, wherein the memory device comprises a microprocessor.

27. The communication device of claim 23, wherein the video compressor comprises means for compressing the digitized video information into a format suitable for transmission over the radio communication resource.

28. The communication device of claim 27, wherein the format suitable for transmission over the radio communication resource comprises a Moving Pictures Experts Group (MPEG) format.

29. The communication device of claim 23, wherein the radio frequency modem comprises:

means for modulating the compressed video output signal into a radio frequency transmission format; and

means for demodulating a received radio frequency signal into a compressed video format.

30. A radio frequency video communication system comprising:

a plurality of video devices;

a plurality of mobile radio communication devices, each of the plurality of mobile radio communication devices being coupled to at least one of the plurality of video devices and having two modes of operation,

in a first mode of operation, receiving video information from at least one video device and transmitting the video information via a radio communication resource at a first transmission frame rate;

in a second mode of operation, receiving video information from the at least one video device and transmitting the video information via a radio communication resource at a second transmission frame rate, wherein the second transmission frame rate is less than the first transmission frame rate;

a radio system infrastructure that provides the radio communication resource; and

a video control server, coupled to the plurality of mobile radio communication devices via the radio system infrastructure, that (i) selects a mode of operation of the two modes of operation for at least one mobile radio communication device of the plurality of mobile radio communication devices based on a priority between transmission frame rate and resolution per frame, and (ii) communicates the mode of operation to the at least one mobile radio communication device via the radio system infrastructure.