Server side stream switching

• US 9,015,335 B1
• Filed: 06/17/2009
• Issued: 04/21/2015
• Est. Priority Date: 06/17/2009
• Status: Active Grant

• Current Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Original Assignee: Amazon Technologies, Inc. (Amazon.com, Inc.)
• Inventors: Gigliotti, Samuel S., Richardson, David R., Evans, Ethan Z., Paleja, Ameesh, Saraf, Tal, Cobb, Matthew B.
• Primary Examiner(s): TODD, GREGORY G
• Application Number:
  US12/486,257
• Time in Patent Office: 2,134 Days
• Field of Search: 709/219, 709231-233, 348/419.1, 348/415.1, 725/96
• US Class Current: 709/231
• CPC Class Codes: G06F 16/40 of multimedia data, e.g. slideshows comprising image and additional audio data retrieval of still image data G06F16/50; retrieval of audio data G06F16/60; retrieval of video data G06F16/70
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/762 at the source reformatting of additional data in video distribution servers H04N21/2355
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements
• CPC Class Codes: H04N 21/23424 involving splicing one content stream with another content stream, e.g. for inserting or substituting an advertisement
• CPC Class Codes: H04N 21/23439 for generating different versions
• CPC Class Codes: H04N 21/2402 Monitoring of the downstream path of the transmission network, e.g. bandwidth available traffic monitoring in data switching networks H04L43/00; monitoring data switching networks utilization H04L43/0876
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/6587 Control parameters, e.g. trick play commands, viewpoint selection
• CPC Class Codes: H04N 21/8455 involving pointers to the content, e.g. pointers to the I-frames of the video stream

Abstract

Technology is provided for dynamically adjusting the delivery of content by switching streams during delivery in order to adapt to bandwidth information. A server (or set of servers) storing content transmits one or more portions of a first version of a set content to a client and monitors that transmission (or other transmission) to determine bandwidth information. The server determines whether to switch versions of the set of content based on the bandwidth information. One or more additional portions of the first version of the set of content are transmitted from the server to the client if the server determines that it should not switch versions of the set of content. One or more portions of a second version of the set of content are transmitted from the server to the client if the server determines that it should switch versions. The first version of the set of content and the second version of the set of content are at different quality levels.

Claims

1. A method of providing content, comprising:

under control of one or more computer systems configured with executable instructions,

receiving, from a client to a content provider, a first request for a first subset of the content, the content corresponding to a plurality of versions, each of the plurality of versions corresponding to a different quality level;

transmitting, from the content provider to the client, a first portion of the content in response to the first request, the first portion comprising a default version of the content and corresponding to the first request for the first subset of the content;

determining, by the content provider, a transmission rate at which the client receives the first portion of the content;

receiving, from the client to the content provider, a second request for a second subset of the content;

estimating, by the content provider, a respective bit rate for transmitting each of the plurality of versions of the content to the client based at least in part on the transmission rate;

determining, by the content provider, a plurality of threshold values for the plurality of versions of the content, a respective threshold value being based at least in part on the respective bit rate for a respective version of the plurality of versions and a respective predetermined factor based on a respective quality level of the respective version;

selecting, by the content provider, a specific version of the plurality of versions based at least in part on comparing the transmission rate to the plurality of threshold values;

generating a new key frame based at least in part on a first frame of the specific version in response to determining that the first frame is between key frames, the first frame corresponding to a start of the second subset of the content;

re-encoding one or more frames of the specific version based at least in part on the new key frame, the one or more re-encoded frames following the first frame and sequenced prior to a next key frame of the specific version; and

transmitting, from the content provider to the client, a second portion of the content in response to the second request, the second portion comprising the new key frame, the one or more re-encoded frames, and a remaining portion of the specific version that follows the next key frame and that corresponds to the second request for the second subset of the content.

2. The method of claim 1, further comprising:

transmitting state information relating to the first portion of the content, the state information identifying the default version of the content and a first position in the default version of the content, the first position corresponding at least in part to the first subset of the content, the second request for the second subset of the content including the state information;

identifying the second portion of the content using the state information received with the second request for the second subset; and

generating updated state information that identifies the specific version and a second position in the specific version of the content, the second position corresponding at least in part to the second subset of the content; and

transmitting the updated state information relating to the second portion of the content.

3. The method of claim 2, wherein identifying the second portion of the content using the state information further includes:

identifying a time value associated with the first position in the default version of the content; and

identifying a byte position in the specific version of the content that is associated with the time value.

4. The method of claim 1, wherein:

a first point of presence of a content delivery network receives the first request and transmits the first portion of the content; and

a second point of presence of the content delivery network receives the second request and transmits the second portion of the content.

5. A method of providing content, comprising:

under control of one or more computer systems configured with executable instructions,

transmitting, from a content provider to a client, a first portion of the content, the content corresponding to a plurality of versions, each of the plurality of versions corresponding to a different quality level, the first portion comprising a default version of the content;

determining, by the content provider, a transmission rate at which the client receives the first portion of the content;

estimating, by the content provider, a respective bit rate for transmitting each of the plurality of versions of the content to the client based at least in part on the transmission rate;

determining, by the content provider, a plurality of threshold values for the plurality of versions of the content, a respective threshold value being based at least in part on the respective bit rate for a respective version of the plurality of versions and a respective predetermined factor based on a respective quality level of the respective version;

selecting, by the content provider, a specific version of the plurality of versions based at least in part on comparing the transmission rate to the plurality of threshold values;

generating a new key frame based at least in part on a first frame of the specific version in response to determining that the first frame is between key frames, the first frame corresponding to a start of a second portion of the content;

re-encoding one or more frames of the specific version based at least in part on the new key frame, the one or more re-encoded frames following the first frame and sequenced prior to a next key frame of the specific version; and

transmitting, from the content provider to the client, the second portion of the content, the second portion comprising the new key frame, the one or more re-encoded frames, and a remaining portion of the specific version that follows the next key frame.

6. The method of claim 5, further comprising

transmitting a first identification of the default version of the content and a first position in the default version of the content relating to the first portion of the content;

receiving a request for the second portion of the content, the request including the first identification of the default version of the content and the first position in the default version of the content;

identifying the second portion of the content using at least the first identification of the default version and the first position, the first position being translated to a position in the specific version of the content if the specific version is not the default version; and

transmitting a second identification of the specific version of the content and a second position in the specific version of the content relating to the second portion.

7. The method of claim 6, wherein translating the first position comprises:

identifying a time code based on the first position in the default version of the content; and

identifying a data position in the specific version of the content based on the time code.

8. The method of claim 6, wherein identifying the second portion of the content further comprises:

identifying a data position in the specific version of the content based on the first position in the default version of the content, the first position in the default version of the content corresponding to a time value.

9. The method of claim 5, wherein:

a first point of presence of a content delivery network transmits the first portion of the content; and

a second point of presence of the content delivery network transmits the second portion of the content.

10. The method of claim 5, wherein:

the default version of the content and the specific version of the content are not a same quality level; and

the first portion and the second portion are portions of a common video.

11. A method of providing content, comprising:

under control of one or more computer systems configured with executable instructions,

receiving, from a client to a content provider, a first request for the content, the content corresponding to a plurality of versions, each of the plurality of versions corresponding to a different quality level;

sending, from the content provider to the client, an acknowledgement of the first request, the acknowledgement including information about a first version of the content;

receiving, from the client to the content provider, a second request for a first range in the first version of the content;

transmitting, from the content provider to the client, a first portion of the content in response to the second request, the first portion comprising a default version of the content and corresponding to the first range in the first version of the content;

determining, by the content provider, a transmission rate at which the client receives the first portion of the content;

receiving, from the client to the content provider, a third request for a second range in the first version of the content;

estimating, by the content provider, a respective bit rate for transmitting each of the plurality of versions of the content to the client based at least in part on the transmission rate;

determining, by the content provider, a plurality of threshold values for the plurality of versions of the content, a respective threshold value being based at least in part on the respective bit rate for a respective version of the plurality of versions and a respective predetermined factor based on a respective quality level of the respective version;

selecting, by the content provider, a specific version of the plurality of versions based at least in part on comparing the transmission rate to the plurality of threshold values;

generating a new key frame based at least in part on a first frame of the specific version in response to determining that the first frame is between key frames, the first frame corresponding to a start of the second range in the first version of the content;

re-encoding one or more frames of the specific version based at least in part on the new key frame, the one or more re-encoded frames following the first frame and sequenced prior to a next key frame of the specific version; and

transmitting, from the content provider to the client, a second portion of the content in response to the third request, the second portion comprising the new key frame, the one or more re-encoded frames, and a remaining portion of the specific version that follows the next key frame and that corresponds the second range in the first version of the content.

12. The method of claim 11, further comprising:

in response to transmitting the second portion of the content, receiving a fourth request for a third range in the first version of the content;

determining a second transmission rate of transmitting the second portion of the content;

selecting a second version of the plurality of versions based at least in part on the second transmission rate; and

transmitting a third portion of the content in response to the third request, the third portion comprising the second version of the content and corresponding to the third range in the first version of the content.

13. The method of claim 11, further comprising:

transmitting a first identification of the default version of the content and a first position in the default version of the content; and

transmitting a second identification of the specific version of the content and a second position in the specific version of the content,

wherein the second request includes the first identification of the default version of the content and the first position in the default version of the content, and

wherein the third request includes the second identification of the specific version of the content and the second position in the specific version of the content.

14. One or more processor readable storage devices having processor readable code embodied on the one or more processor readable storage devices, the processor readable code for programming one or more processors to perform a method comprising:

receiving, from a client to a content provider, a first request for the content, the content corresponding to a plurality of versions, each of the plurality of versions corresponding to a different quality level;

sending, from the content provider to the client, an acknowledgement of the first request, the acknowledgement including information about a first version of the content;

receiving, from the client to the content provider, a second request for a first range in the first version of the content;

transmitting, from the content provider to the client, a first portion of the content in response to the second request, the first portion comprising a default version of the content and corresponding to the first range in the first version of the content;

determining, by the content provider, a transmission rate at which the client receives the first portion of the content;

receiving, from the client to the content provider, a third request for a second range in the first version of the content;

estimating, by the content provider, a respective bit rate for transmitting each of the plurality of versions of the content to the client based at least in part on the transmission rate;

determining, by the content provider, a plurality of threshold values for the plurality of versions of the content, a respective threshold value being based at least in part on the respective bit rate for a respective version of the plurality of versions and a respective predetermined factor based on a respective quality level of the respective version;

selecting, by the content provider, a specific version of the plurality of versions based at least in part on comparing the transmission rate to the plurality of threshold values;

generating a new key frame based at least in part on a first frame of the specific version in response to determining that the first frame is between key frames, the first frame corresponding to a start of the second range in the first version of the content;

re-encoding one or more frames of the specific version based at least in part on the new key frame, the one or more re-encoded frames following the first frame and sequenced prior to a next key frame of the specific version; and

transmitting, from the content provider to the client, a second portion of the content in response to the third request, the second portion comprising the new key frame, the one or more re-encoded frames, and a remaining portion of the specific version that follows the next key frame and that corresponds to the second range in the first version of the content.

15. The one or more processor readable storage devices of claim 14, the method further comprising:

transmitting a first identification of the default version of the content and a first position in the default version of the content; and

transmitting a second identification of the specific version of the content and a second position in the specific version of the content,

wherein the second request includes the first identification of the default version of the content and the first position in the default version of the content, and

wherein the third request includes the second identification of the specific version of the content and the second position in the specific version of the content.

16. A system for providing content, comprising:

a processor; and

a memory device including instructions that, when executed by the processor, cause the processor to;

transmit, from a content provider to a client, a first portion of the content, the content corresponding to a plurality of versions, each of the plurality of versions corresponding to a different quality level, the first portion comprising a default version of the content;

determine, by the content provider, a transmission rate at which the client receives the first portion of the content;

estimate, by the content provider, a respective bit rate for transmitting each of the plurality of versions of the content to the client based at least in part on the transmission rate;

determine, by the content provider, a plurality of threshold values for the plurality of versions of the content, a respective threshold value being based at least in part on the respective bit rate for a respective version of the plurality of versions and a respective predetermined factor based on a respective quality level of the respective version;

select, by the content provider, a specific version of the plurality of versions based at least in part on comparing the transmission rate to the plurality of threshold values;

generate a new key frame based at least in part on a first frame of the specific version in response to determining that the first frame is between key frames, the first frame corresponding to a start of a second portion of the content;

re-encode one or more frames of the specific version based at least in part on the new key frame, the one or more re-encoded frames following the first frame and sequenced prior to a next key frame of the specific version; and

transmit, from the content provider to the client, the second portion of the content, the second portion comprising the new key frame, the one or more re-encoded frames, and a remaining portion of the specific version that follows the next key frame.

17. The system of claim 16, wherein the memory device includes the instructions that, when executed by the processor, further cause the processor to:

transmit a first identification of the default version of the content and a first position in the default version of the content relating to the first portion of the content;

receive a request for the second portion of the content, the request including the first identification of the default version of the content and the first position in the default version of the content;

identify the second portion of the content using at least the first identification of the default version and the first position, the first position being translated to a position in the specific version of the content if the specific version is not the default version; and

transmit a second identification of the specific version of the content and a second position in the specific version of the content relating to the second portion.