Method and apparatus for estimating frame rate for data rate control

• US 6,108,447 A
• Filed: 03/26/1998
• Issued: 08/22/2000
• Est. Priority Date: 03/26/1998
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Lord, Christopher, McVeigh, Jeffrey S.
• Primary Examiner(s): Couso, Jose L.
• Assistant Examiner(s): Do, Anh Hong
• Application Number:
  US09/049,287
• Time in Patent Office: 880 Days
• Field of Search: 382/232, 382/235, 382/244, 370/280, 379/202, 345/420, 348/405
• US Class Current: 382/232
• CPC Class Codes: G06T 9/007 Transform coding, e.g. discrete cosine transform

Abstract

A method for managing data in a video sequence includes estimating a frame rate of the video sequence using time stamps of instructions received from an application program interface. A number of bits is allocated for encoding frames in the video sequence according to a data rate and the frame rate.

Claims

1. A method for managing data in a video sequence, comprising:

estimating a frame rate of the video sequence using time stamps of instructions received from an application program interface, the time stamps being real-time representations of when the instructions are received from the application program interface; and

allocating a number of bits for encoding frames in the video sequence based on a data rate and the frame rate.

2. The method of claim 1, wherein estimating the frame rate of the video sequence comprises:

determining when a first function call is made to compress data corresponding to a first frame in the video sequence from the application program interface;

recording a time when the first function call was made;

determining when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface;

recording a time when the second function call was made; and

dividing a number of frames that have been called to be compressed after the first frame by a time elapsed between when the first function call and the second function call were made.

3. The method of claim 1, wherein allocating the number of bits for encoding the frames in the video sequence comprises dividing the data rate by the frame rate.

4. The method of claim 1, further comprising:

determining a data rate from user input.

5. The method of claim 1, wherein the managing of the graphical data is performed in real-time in a Video for Windows®

compliant video encoder.

6. A computer-readable medium having stored thereon sequences of instructions, the sequences of instructions including instructions which, when executed by a processor, causes the processor to perform:

estimating a frame rate of a video sequence using time stamps of instructions received from an application program interface, the time stamps being real-time representations of when the instructions are received from the application program interface; and

allocating a number of bits for encoding frames in the video sequence based on a data rate and the frame rate.

7. The computer-readable medium of claim 6, wherein estimating the frame rate of the video sequence comprises:

determining when a first function call is made to compress data corresponding to a first frame in the video sequence from the application program interface;

recording a time when the first function call was made;

determining when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface;

recording a time when the second function call was made; and

dividing a number of frames that have been called to be compressed after the first frame a time elapsed between when the first function call and the second function call were made.

8. The computer-readable medium of claim 6, wherein allocating the number of bits for encoding the frames in the video sequence comprises dividing the data rate by the frame rate.

9. The computer-readable medium of claim 6 further comprising instructions which, when executed by the processor, causes the processor to perform:

determining a data rate from user input.

10. The computer-readable medium of claim 6, wherein the managing of the graphical data is performed in real-time in a Video for Windows®

compliant video encoder.

11. A video encoder, comprising:

a coding manager that calculates a bit allocation number to encode frames in a video sequence using time stamps of instructions received from an application program interface, the time stamps being real-time representations of when the instructions are received from the application program interface; and

a video coding unit coupled to the coding manager that encodes the frames in the video sequence based on the bit allocation number.

12. The video encoder of claim 11, wherein the coding manager comprises:

a data rate storage unit that stores a data rate value which the video sequence is to be transmitted;

a frame rate estimating unit that estimates a frame rate of the video sequence; and

a bit allocation unit coupled to the data rate storage unit and the frame rate estimation unit that calculates the bit allocation number based on the data rate value and the frame rate.

13. The video encoder of claim 12, wherein the frame rate estimating unit comprises:

a time stamp unit that records a first time when a first function call is made to compress data corresponding a first frame in the video sequence from the application program interface and a second time when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface;

a frame counter that records a number of frames that have been called to be compressed after the first frame; and

a frame rate estimator coupled to the time stamp unit and the frame counter that estimates the frame rate by dividing the number of frames that have been called to be compressed after the first frame by a time elapsed between when the first function call and the second function call were made with.

14. The video encoder of claim 12, wherein the bit allocation unit calculates the bit allocation number by dividing the data rate value by the frame rate.

15. A computer system, comprising:

a bus;

a processor coupled to the bus; and

a video encoder that includes a coding manager that calculates a bit allocation number to encode frames in a video sequence using time stamps of instructions received from an application program interface and a video coding unit coupled to the coding manager that encodes the frames in the video sequence according to the bit allocation number, and wherein the time stamps being real-time representations of when the instructions are received from the application program interface.

16. The computer system of claim 15, wherein the coding manager comprises:

a data rate storage unit that stores a data rate value which the video sequence is to be transmitted;

a frame rate estimating unit that estimates a frame rate of the video sequence; and

a bit allocation unit coupled to the data rate storage unit and the frame rate estimation unit that calculates the bit allocation number based on the data rate value and the frame rate.

17. The computer system of claim 16, wherein the frame rate estimating unit comprises:

a time stamp unit that records a first time when a first function call is made to compress data corresponding a first frame in the video sequence from the application program interface and a second time when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface;

a frame counter that records a number of frames that have been called to be compressed after the first frame; and

a frame rate estimator coupled to the time stamp unit and the frame counter that estimates the frame rate by dividing the number of frames that have been called to be compressed after the first frame by a time elapsed between when the first function call and the second function call were made.

18. The computer system of claim 15, wherein the bit allocation unit calculates the bit allocation number by dividing the data rate value by the frame rate.

19. A method for managing data in a video sequence, comprising:

estimating a frame rate of the video sequence using time stamps of instructions received from an application program interface, and wherein estimating the frame rate of the video sequence including;

determining when a first function call is made to compress data corresponding to a first frame in the video sequence from the application program interface,

recording a time when the first function call was made;

determining when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface,

recording a time when the second function call was made, and

dividing a number of frames that have been called to be compressed after the first frame by a time elapsed between when the first function call and the second function call were made; and

allocating a number of bits for encoding frames in the video sequence based on a data rate and the frame rate.

20. A computer-readable medium having stored thereon sequences of instructions, the sequences of instructions including instructions which, when executed by a processor, causes the processor to perform:

estimating a frame rate of a video sequence using time stamps of instructions received from an application program interface, and wherein estimating the frame rate of the video sequence including;

determining when a first function call is made to compress data corresponding to a first frame in the video sequence from the application program interface,

recording a time when the first function call was made,

determining when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface,

recording a time when the second function call was made, and

dividing a number of frames that have been called to be compressed after the first frame a time elapsed between when the first function call and the second function call were made; and

allocating a number of bits for encoding frames in the video sequence based on a data rate and the frame rate.

21. A video encoder, comprising:

a coding manager that calculates a bit allocation number to encode frames in a video sequence using of instructions received from an application program interface, the coding manager including;

a data rate storage unit that stores a data rate value which the video sequence is to be transmitted,

a frame rate estimating unit that estimates a frame rate of the video sequence, the frame estimating unit including;

a time stamp unit that records a first time when a first function call is made to compress data corresponding a first frame in the video sequence from the application program interface and a second time when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface,

a frame counter that records a number of frames that have been called to be compressed after the first frame, and

a frame rate estimator coupled to the time stamp unit and the frame counter that estimates the frame rate by dividing the number of frames that have been called to be compressed after the first frame by a time elapsed between when the first function call and the second function call were made with, and

a bit allocation unit coupled to the data rate storage unit and the frame rate estimation unit that calculates the bit allocation number based on the data rate value and the frame rate; and

a video coding unit coupled to the coding manager that encodes the frames in the video sequence based on the bit allocation number.

22. A computer system, comprising:

a bus;

a processor coupled to the bus; and

a video encoder that includes a coding manager that calculates a bit allocation number to encode frames in a video sequence using of instructions received from an application program interface and a video coding unit coupled to the coding manager that encodes the frames in the video sequence based on the bit allocation number, the coding manager including;

a data rate storage unit that stores a data rate value which the video sequence is to be transmitted,

a frame rate estimating unit that estimates a frame rate of the video sequence, the frame rate estimating unit including;

a time stamp unit that records a first time when a first function call is made to compress data corresponding a first frame in the video sequence from the application program interface and a second time when a second function call is made to compress data corresponding to a second frame in the video sequence from the application program interface,

a frame counter that records a number of frames that have been called to be compressed after the first frame, and

a frame rate estimator, coupled to the time stamp unit and the frame counter, that estimates the frame rate by dividing the number of frames that have been called to be compressed after the first frame by a time elapsed between when the first function call and the second function call were made, and

a bit allocation unit coupled to the data rate storage unit and the frame rate estimation unit that calculates the bit allocation number based on the data rate value and the frame rate.