METHOD AND APPARATUS FOR CAPTURING AN IMAGE

• US 20140321541A1
• Filed: 04/30/2013
• Published: 10/30/2014
• Est. Priority Date: 04/30/2013
• Status: Abandoned Application

• Current Assignee: Motorola Solutions, Inc.
• Original Assignee: Motorola Solutions, Inc.
• Inventors: KLEIN, DAVID E., BEKIARES, TYRONE D., O'CONNEL, KEVIN J.
• Application Number:
  US13/873,928
• Publication Number:
  US 20140321541A1
• Time in Patent Office: Days
• US Class Current: 375/240.08
• CPC Class Codes: H04N 19/105 Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
• CPC Class Codes: H04N 19/107 between spatial and temporal predictive coding, e.g. picture refresh
• CPC Class Codes: H04N 19/136 Incoming video signal characteristics or properties
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/172 the region being a picture, frame or field
• CPC Class Codes: H04N 19/58 Motion compensation with long-term prediction, i.e. the reference frame for a current frame not being the temporally closest one H04N19/23 takes precedence
• CPC Class Codes: H04N 19/87 involving scene cut or scene change detection in combination with video compression
• CPC Class Codes: H04N 21/41422 located in transportation means, e.g. personal vehicle arrangements specially adapted for transportation systems in broadcast systems H04H20/62
• CPC Class Codes: H04N 21/42202 environmental sensors, e.g. for detecting temperature, luminosity, pressure, earthquakes
• CPC Class Codes: H04N 21/4223 Cameras H04N23/00 takes precedence
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27

Abstract

A method and apparatus are provided for capturing video so that compression and quality can be optimized. During operation, a video recording system will employ a learning algorithm to determine periods when a light bar is on, or active. Reference Intra frames are then stored and used for the subsequent creation of predictive frames. More particularly, at least a first Intra frame is stored and used for creating predictive frames during periods of light bar activity. In a similar manner, a second Intra frame is stored and used for creating predictive frames during periods of light bar inactivity. By learning the light bar pattern, Intra frames can be more intelligently selected, resulting in optimized compression and quality.

Claims

1. A method comprising the steps of:

learning a strobe pattern for a light source;

choosing an Intra frame from a plurality of possible Intra frames based on the strobe pattern for the light source; and

encoding video utilizing the chosen Intra frame as a reference for encoding subsequent predictive frames.

2. The method of claim 1 further comprising the steps of:

creating and storing Intra frames for use when the light source is active; and

creating and storing Intra frames for use when the light source is inactive.

3. The method of claim 1 wherein the step of learning the strobe pattern for the light source comprises the step of determining when the light source will be active.

4. The method of claim 3 wherein:

the light source reputedly strobes multiple colors at predictable times; and

the step of determining comprises the step of determining the occurrence of a particular color at a particular time.

5. The method of claim 4 wherein the multiple colors comprises colors from the group consisting of red, blue, white, and amber.

6. The method of claim 1 wherein the light source comprises a light bar on a public safety or public service/utility vehicle.

7. The method of claim 1 wherein the plurality of possible Intra frames comprises a newest Intra frame and an older Intra frame, and wherein the step of choosing the Intra frame comprises the step of choosing the older Intra frame from the plurality of possible Intra frames.

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

sending programming instructions to the light source; and

learning the strobe pattern from the programming instructions sent to the light source.

9. The method of claim 1 wherein the step of learning comprises the steps of:

identifying a repeating pattern of color and luminance values within a histogram.

10. A method for encoding video, the method comprises the steps of:

determining periods when a light bar on a public safety vehicle will be active;

determining periods when the light bar on the public safety vehicle will be inactive;

acquiring “

active”

Intra frames for encoding during a determined period of light bar activity;

acquiring ‘

inactive”

Intra frames for encoding video during a determined period of light bar inactivity;

storing the active and inactive Intra frames for future encoding of video;

receiving a video frame for encoding;

determining if the light bar was active or inactive during the acquisition of the video frame; and

using the stored active Intra frame or the stored inactive Intra frame for encoding the video frame based on the determination if the light bar was active or inactive during the acquisition of the video frame.

11. The method of claim 10 wherein the stored active and inactive Intra frames comprise a newest Intra frame and an older Intra frame, and wherein the step of using the stored active Intra frame or stored inactive Intra frame comprises the step of using the older Intra frame from the plurality of stored Intra frames.

12. The method of claim 10 wherein the step of determining periods when the light bar on the public safety vehicle will be active, and the step of determining periods when the light bar on the public safety vehicle will be inactive comprises the step of determining based on a chromium and luminance value in a color histogram.

13. The method of claim 10 further comprising the steps of:

determining that the encoded video frame required an amount of texture encoding greater than a threshold; and

again determining periods when the light bar on the public safety vehicle will be active;

again determining periods when the light bar on the public safety vehicle will be inactive.

14. A public safety vehicle comprising:

a light bar;

a computer determining periods when a light bar on a public safety vehicle will be active, and determining periods when the light bar on the public safety vehicle will be inactive;

a camera;

wherein the computer acquiring from the camera “

active”

Intra frames for encoding during a determined period of light bar activity and acquiring “

inactive”

Intra frames for encoding video during a determined period of light bar inactivity;

storage storing the active and inactive Intra frames for future encoding of video;

wherein the computer receives a video frame from the camera, determines if the light bar was active or inactive during the acquisition of the video frame, and uses the stored active Intra frame or the stored inactive Intra frame for encoding the video frame based on the determination if the light bar was active or inactive during the acquisition of the video frame.

15. The public safety vehicle of claim 14 wherein the storage comprises a newest Intra frame and an older Intra frame, and wherein the computer uses the older Intra frame from the plurality of stored Intra frames for encoding the video frame.

16. The public safety vehicle of claim 15 wherein the computer determines based on a chromium and luminance value in a color histogram.

17. The public safety vehicle of claim 14 wherein the computer, based on an amount of texture encoding being above a threshold, will again determine periods when the light bar on the public safety vehicle will be active and inactive