Shared memory pool allocation during media rendering

• US 7,698,528 B2
• Filed: 06/28/2007
• Issued: 04/13/2010
• Est. Priority Date: 06/28/2007
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Freeman, Arthur William James, Finger, James C., Colle, Olivier
• Primary Examiner(s): KIM, HONG CHONG
• Application Number:
  US11/823,510
• Publication Number:
  US 20090006771A1
• Time in Patent Office: 1,020 Days
• Field of Search: 345/543, 345/619, 345/668, 711/170
• US Class Current: 711/170
• CPC Class Codes: G06F 9/5016 the resource being the memory
• CPC Class Codes: H04N 19/127 Prioritisation of hardware or computational resources
• CPC Class Codes: H04N 19/423 characterised by memory arrangements H04N19/433 takes precedence

Abstract

Memory management techniques involve establishing a memory pool having an amount of sharable memory, and dynamically allocating the sharable memory to concurrently manage multiple sets of sequenced units of digital data. In an exemplary scenario, the sets of sequenced units of digital data are sets of time-ordered media samples forming clips of media content, and the techniques are applied when media samples from two or more clips are simultaneously presentable to a user as independently-controlled streams. Variable amounts of sharable memory are dynamically allocated for preparing upcoming media samples for presentation to the user. In one possible implementation, a ratio of average data rates of individual streams is calculated, and amounts of sharable memory are allocated to rendering each stream based on the ratio. Then, the sharable memory allocated to rendering individual streams is reserved as needed to prepare particular upcoming media samples for presentation to the user.

Claims

1. A computer-readable storage medium encoded with computer-executable instructions which, when executed by a processor, perform a method for managing digital data using a memory pool having an amount of sharable memory, the digital data comprising a plurality of sets of sequenced units of digital data, the method comprising:

identifying a first set of units of digital data having a first sequence;

identifying a second set of units of digital data having a second sequence;

when a portion of the first set is to be processed contemporaneously with a portion of the second set,

ascertaining a first resource consumption indicator associated with processing some of the units of digital data in the first sequence;

ascertaining a second resource consumption indicator associated with processing some of the units of digital data in the second sequence;

calculating a ratio of the first resource consumption indicator with respect to the second resource consumption indicator; and

in accordance with the ratio, dynamically allocating the amount of sharable memory in the memory pool between both acts associated with processing the first set and acts associated with processing the second set.

2. The computer-readable storage medium according to claim 1, wherein the method further comprises:

when a portion of the first set is not to be contemporaneously processed with a portion of the second set, dynamically allocating the amount of sharable memory in the memory pool to either acts associated with processing the first set or acts associated with processing the second set, but not both.

3. The computer-readable storage medium according to claim 1, wherein the first and second resource consumption indicators comprise average resource consumption rates associated with processing the first and second sets of units of digital data, respectively.

4. The computer-readable storage medium according to claim 1, wherein the method further comprises:

when a portion of the first set is to be processed contemporaneously with a portion of the second set,

ascertaining that an amount of available sharable memory is insufficient for allocation in accordance with the ratio;

assigning a priority to either acts associated with processing the first set of digital units or acts associated with processing the second set of digital units; and

dynamically allocating the amount of sharable memory in the memory pool based on the assigned priority.

5. The computer-readable storage medium according to claim 4, wherein the step of allocating the amount of sharable memory in the memory pool based on the priority comprises

when the priority is assigned to acts associated with processing the first set, allocating the amount of sharable memory in the memory pool to acts associated with processing the first set, and

when the priority is assigned to acts associated with processing the second set, dynamically allocating the amount of sharable memory in the memory pool to acts associated with processing the second set.

6. The computer-readable storage medium according to claim 1, wherein either the first sequence or the second sequence or both are either pre-determined or dynamically determined.

7. A computer-readable storage medium encoded with computer-executable instructions which, when executed by a processor, perform a method for rendering media content using a sharable memory pool, the media content arranged into a plurality of sets of sequenced media samples, the method comprising:

identifying a first set of media samples receivable from a first media source;

identifying a second set of media samples receivable from a second media source;

calculating a first data rate associated with rendering the first set of media samples;

calculating a second data rate associated with rendering the second set of media samples;

comparing the first data rate to the second data rate; and

based on the step of comparing, dynamically allocating a first amount of memory from the sharable memory pool for rendering the first set of media samples, and a second amount of memory from the sharable memory pool for contemporaneously rendering the second set of media samples.

8. The computer-readable medium according to claim 7, the method further comprising:

identifying a first upcoming media sample from the first set of media samples;

identifying a second upcoming media sample from the second set of media samples, the second upcoming media sample to be rendered contemporaneously with the first upcoming media sample;

ascertaining a first desired memory amount for rendering the first upcoming media sample;

ascertaining a second desired memory amount for rendering the second upcoming media sample;

when an amount of memory available from the sharable memory pool is sufficient for dynamically allocating both the first desired memory amount and the second desired memory amount,

dynamically allocating the first desired memory amount for rendering the first upcoming media sample and reducing the amount of memory available from the sharable memory pool by the first desired memory amount, and

dynamically allocating the second desired memory amount for rendering the second upcoming media sample and reducing the amount of memory available from the sharable memory pool by the second desired memory amount; and

when an amount of memory available from the sharable memory pool is insufficient for dynamically allocating both the first desired memory amount and the second dynamic memory amount,

either dynamically allocating the first desired memory amount for rendering the first upcoming media sample and reducing the amount of memory available from the sharable memory pool by the first desired memory amount, or

dynamically allocating the second desired memory amount for rendering the second upcoming media sample and reducing the amount of memory available from the sharable memory pool by the second desired memory amount.

9. The computer-readable medium according to claim 8, wherein when an amount of memory available from the sharable memory pool is insufficient for dynamically allocating both the first desired memory amount and the second dynamic memory amount,

dynamically allocating the first desired memory amount when the first data rate is higher than the second data rate, and

dynamically allocating the second desired memory amount when the second data rate is higher than the first data rate.

10. The computer-readable medium according to claim 8, the method further comprising:

when the first desired memory amount has been dynamically allocated, after the first upcoming media sample has been rendered, increasing the amount of memory available from the sharable memory pool by the first desired memory amount; and

when the second desired memory amount has been dynamically allocated, after the second upcoming media sample has been rendered, increasing the amount of memory available from the sharable memory pool by the second desired memory amount.

11. The computer-readable medium according to claim 8, the method further comprising:

when an amount of memory available from the sharable memory pool is insufficient for dynamically allocating both the first desired memory amount and the second dynamic memory amount, assigning a memory allocation priority to the first desired memory amount when the second desired memory amount was dynamically allocated, or assigning an allocation priority to the second desired memory amount when the first desired memory amount was dynamically allocated;

when the allocation priority is assigned to the first desired memory amount and the amount of memory available from the sharable memory pool becomes equal to or greater than the first desired memory amount, automatically dynamically allocating the first desired memory amount from the sharable memory pool; and

when the allocation priority is assigned to the second desired memory amount and the amount of memory available from the sharable memory pool becomes equal to or greater than the second desired memory amount, automatically dynamically allocating the first desired memory amount from the sharable memory pool.

12. The computer-readable medium according to claim 7, wherein the first media source is the same as or different than the second media source, and

wherein media samples are selected from the group consisting of:

bits;

frames;

data packets;

groups of pictures; and

enhanced video object units.

13. The computer-readable medium according to claim 7, wherein the step of comparing comprises calculating a ratio of the first data rate with respect to the second data rate, and wherein the step of dynamically allocating comprises dynamically allocating in accordance with the ratio.

14. The computer-readable medium according to claim 7, wherein the first data rate comprises an average data rate calculated based on information selected from the group consisting of:

a rendering speed of the first set of media samples;

a characteristic of the presentation system; and

a characteristic of the first media source, and

wherein the second data rate comprises an average data rate calculated based on information selected from the group consisting of;

a rendering speed of the second set of media samples;

a characteristic of the presentation system; and

a characteristic of the second media source.

15. The computer-readable medium according to claim 14, wherein the characteristics of the presentation system are selected from the group consisting of:

a play state of the first set of media samples or the second set of media samples or both;

a processing load within the presentation system; and

a frequency of a clock associated with the presentation system.

16. The computer-readable medium according to claim 14, wherein the characteristics of the first and second media sources are selected from the group consisting of:

encoder-decoder pair parameters; and

encryption parameters.

17. The computer-readable medium according to claim 14, wherein the step of calculating an average data rate associated with rendering media samples of the first set comprises

ascertaining an amount of memory of the sharable memory pool currently allocated for rendering the first set of media samples,

ascertaining a size of a first number of media samples of the first set that are currently being rendered,

ascertaining a first amount of time associated with playing to a user the first number of media samples, and

dividing the size of the first number of media samples by the first amount of time, and

wherein the step of calculating an average data rate associated with rendering media samples of the second set comprises

ascertaining an amount of memory of the sharable memory pool currently allocated for rendering the second set of media samples, ascertaining a size of a second number of media samples of the second set that are currently being rendered,

ascertaining a second amount of time associated with playing to a user the second number of media samples, and

dividing the size of the second number of media samples by the second amount of time.

18. A system for rendering media content arranged into a plurality of sets of sequenced media samples, the system comprising:

a media content manager operable to arrange for rendering of a first set of media samples from a first media source and to arrange for rendering of a second set of media samples from a second media source;

a presentation manager configured for communication with the media content manager, the presentation manager operable to identify when a first media sample from the first set is to be rendered contemporaneously with a second media sample from the second set; and

a memory allocation manager responsive to the media content manager and the presentation manager, the memory allocation manager managing a sharable memory pool and operable to

ascertain a first data rate associated with rendering the first set of media samples;

ascertain a second data rate associated with rendering the second set of media samples;

compare the first data rate to the second data rate; and

based on the comparison, dynamically allocate a first amount of memory from the sharable memory pool for rendering the first media sample from the first set of media samples and a second amount of memory from the sharable memory pool for contemporaneously rendering the second media sample from the second set of media samples.

19. The system according to claim 18, wherein the system comprises an operating system.

20. The system according to claim 18, wherein the system comprises a digital media player.