Image frame transmission method for data overrun control

• US 8,194,137 B2
• Filed: 02/02/2005
• Issued: 06/05/2012
• Est. Priority Date: 02/02/2004
• Status: Active Grant

• Current Assignee: VIA Technologies Incorporated (VIA Technologies)
• Original Assignee: VIA Technologies Incorporated (VIA Technologies)
• Inventors: Chiang, Chin-Yi, Huang, Wallace
• Primary Examiner(s): KHAN, USMAN A
• Application Number:
  US11/049,371
• Publication Number:
  US 20050190271A1
• Time in Patent Office: 2,680 Days
• Field of Search: 348/231.6, 348/207.1, 348/14.12, 348/222.1, 348/207.2
• US Class Current: 348/207.1
• CPC Class Codes: H04N 23/661 Transmitting camera control signals through networks, e.g. control via the Internet

Abstract

An image frame transmission method for use in a network transmission system is provided. The network transmission system includes an image sensor and an image processor. Firstly, a first image data segment of an image frame captured by the image sensor is outputted to the image processor in response to a first state of a control signal after an initial signal has been asserted by the image processor. Then, the output of a second image data segment of the image frame following the first image data segment to the image processor is delayed in response to the transition of the control signal from the first state to a second state. Afterward, the second image data segment is outputted to the image processor in response to the transition of the control signal from the second state to the first second state.

Claims

1. An image frame transmission method, performed by a network transmission system comprising an image sensor and an image processor, said method comprising steps of:

said image sensor outputting a first image data segment of an image frame captured by said image sensor to said image processor in response to a first state of a control signal issued by said image processor;

said image processor switching said control signal from said first state to a second state to suspend the output of a second image data segment of said image frame, which is previously captured by said image sensor following said first image data segment, from said image sensor to said image processor if said image processor has not completed processing said first image data segment before the output of said second image data segment from said image sensor, and otherwise remaining said control signal in said first state to have said second image data segment outputted from said image sensor to said image processor immediately following said first image data segment without suspension; and

said image sensor outputting said second image data segment to said image processor in response to the transition of said control signal from said second state to said first state;

wherein a processing period of said image sensor for said image frame is pre-defined with an exposure period for capturing a plurality of image data segments including said first and second image data segments of said image frame, an image data outputting period for continuously outputting said plurality of image data segments of said image frame, and an idle period for waiting to process a next image frame in sequence; and

said plurality of image data segments share said idle period to elongate an image data processing period in which said image frame is completely outputted to said image processor with necessary suspension, to beyond said image data outputting period.

2. The method according to claim 1 wherein said image data processing period is greater than said image data outputting period.

3. The method according to claim 1 wherein said image data processing period is greater than said image data outputting period but not greater than the sum of said image data outputting period and said idle period.

4. The method according to claim 1 wherein said image data processing period is equal to the sum of said image data outputting period and said idle period.

5. The method according to claim 1 wherein said plurality of image data segments share said idle period to elongate said image data processing period by toggling said control signal between said first and second states according to respective conditions of said plurality of image data segments.

6. The method according to claim 1 wherein said first and second states of said control signal are high and low levels.

7. The method according to claim 1 wherein said image sensor is operated in a still image mode.

8. The method according to claim 1 wherein said image sensor is operated in a dynamic image mode.

9. An image frame transmission method, performed by a network transmission system comprising an image sensor and an image processor, a processing period of said image sensor for an image frame being pre-defined with an exposure period for capturing a plurality of image data segments of said image frame, an image data outputting period for continuously outputting said plurality of image data segments of said image frame, and an idle period for waiting to process next image frame in sequence, and said method comprising steps of:

said image processor asserting an initial signal for outputting said image frame within an image data processing period after said exposure period;

said image processor issuing a control signal which periodically toggles between first and second states so that said plurality of image data segments equally share said idle period to elongate said image data processing period to beyond said image data outputting period;

said image sensor outputting said plurality of image data segments to said image processor segment by segment in response to said first state of said control signal;

said image sensor suspending the output of said plurality of image data segments whenever said control signal toggles from said first state to said second state; and

said image sensor restoring the output of said plurality of image data segments in response to the transition of said control signal from said second state to said first second state.

10. The method according to claim 9 wherein said image data processing period is greater than said image data outputting period but not greater than the sum of said image data outputting period and said idle period.

11. The method according to claim 9 wherein said image data processing period is equal to the sum of said image data outputting period and said idle period.

12. The method according to claim 9 wherein said image sensor is operated in a still image mode.

13. The method according to claim 9 wherein said image sensor is operated in a dynamic image mode.