Selection of resolutions for seamless resolution switching of multimedia content

1. A source encoder including a processor and a memory readable by the processor where the memory stores an encoding application that directs the processor to receive a primary video stream and encode the primary video stream into a set of alternative video streams, where the encoding application directs the processor to:

select a primary resolution based on a given aspect ratio of the primary video stream;

determine a set of resolutions for the set of alternative video streams for the given aspect ratio from the primary resolution, wherein:

each resolution of the set of resolutions comprises a height, width, and sample aspect ratio;

the height and width of each resolution of the set of resolutions is an integer number of pixels and is less than the corresponding width and height of the primary resolution;

at least two resolutions of the set of resolutions have different sample aspect ratios; and

each resolution of the set of resolutions results in the given aspect ratio; and

encode a set of alternative video streams from the primary video stream, where each of the alternative video streams is encoded at a different resolution from the set of resolutions and a different bitrate from other video streams in the set of alternative video streams; and

generate an index file, where the index file includes a description of each of the set of alternative video streams, where the description for each alternative video stream comprises the height, the width, the bitrate, and the sample aspect ratio of the resolution at which the alternative stream is encoded.

2. The source encoder of claim 1 , wherein the set of resolutions comprises at least one resolution having a square sample aspect ratio.

3. The source encoder of claim 1 , wherein the index file is dynamically generated in response to a request for the primary video stream.

4. The source encoder of claim 1 , wherein the encoder application directs the processor to determine the set of resolutions for the set of alternative video streams by selecting the set of resolutions from a plurality of height and width combinations, wherein a height and a width for each height and width combination of the plurality of height and width combinations are each whole number fractions of the height and the width of the primary resolution by determining whether a numerator and a denominator of the whole number fraction are below a given threshold.

5. The source encoder of claim 1 , wherein the height and the width for each resolution of the set of resolutions is a multiple of 8.

6. The source encoder of claim 1 , wherein the encoding application further directs the processor to store each of the encoded set of alternative streams in a container file.

7. The source encoder of claim 6 , wherein the encoding application further directs the processor to generate a container index for the container file of each of the encoded set of alternative streams.

8. A method for encoding a primary video stream into a set of alternative video streams, where method comprises:

selecting a primary resolution based on a given aspect ratio of the primary video stream;

determining a set of resolutions for the set of alternative video streams for the given aspect ratio from the primary resolution wherein:

each resolution of the set of resolutions comprises a height, width, and sample aspect ratio;

the height and width of each resolution of the set of resolutions is an integer number of pixels and is less than the corresponding width and height of the primary resolution;

at least two resolutions of the set of resolutions have different sample aspect ratios; and

each resolution of the set of resolutions results in the given aspect ratio;

encoding a set of alternative video streams from the primary video stream, where each of the alternative video streams is encoded at a different resolution from the set of resolutions and a different bitrate from other video streams in the set of alternative video streams; and

generating an index file, where the index file includes a description of each of the set of alternative video streams, where the description for each alternative video stream comprises the height, the width, the bitrate, and the sample aspect ratio of the resolution at which the alternative stream is encoded.

9. The method of claim 8 , wherein the set of resolutions comprises at least one resolution having a square sample aspect ratio.

10. The method of claim 8 , wherein the index file is dynamically generated in response to a request for the primary video stream.

11. The method of claim 8 further comprising determining the set of resolutions for the set of alternative video streams by selecting the set of resolutions from a plurality of height and width combinations, wherein a height and a width for each height and width combination of the plurality of height and width combinations are each whole number fractions of the height and the width of the primary resolution by determining whether a numerator and a denominator of the whole number fraction are below a given threshold.

12. The method of claim 8 , wherein the height and the width for each resolution of the set of resolutions is a multiple of 8.

13. The method of claim 8 further comprising storing each of the encoded set of alternative streams in a container file.

14. The method of claim 13 further comprising generating a container index for the container file of each of the encoded set of alternative streams.