Chunk header incorporating binary flags and correlated variable-length fields
Playback and distribution systems and methods for multimedia files are provided. The multimedia files are encoded with flags associated with the content data of the multimedia files. Through the use of the flags, playback of the content is enhanced without significantly increasing the file size of the multimedia file.
1. A method of playing back content by a playback device, the method comprising:
downloading at least a portion of a media file having content data and a plurality of headers using the playback device, the content data having a plurality of frames of encoded video, wherein at least one of the headers comprises:
a series of flags and a plurality of data fields, wherein the series of flags comprises an extension flag that indicates whether additional flags are included in the header, and
additional flags that are indicated as being a part of the header by the extension flag, wherein the additional flags comprise a frame metadata flag that indicates the presence of frame metadata within the plurality of data fields of the header;
decoding a frame of encoded video by decoding the at least one header to identify the series of flags, the additional flags, and the content of the plurality of data fields and decoding the frame of encoded video based upon a set of pre-defined presentation rules that define the behavior of the playback device based upon the frame metadata; and
displaying the decoded frame of encoded video on a display using the playback device.
2. The method of claim 1 wherein the series of flags and the plurality of data fields of the at least one header reference portions of a frame of encoded video.
3. The method of claim 2 wherein the series of flags includes a forward access flag and the plurality of data fields include a forward offset data field, the forward access flag referencing the forward offset data field.
4. The method of claim 3 wherein the forward offset data field defines a bit-field representation relative to a start point in a media file.
5. The method of claim 2 wherein the series of flags includes a backward access flag and the plurality of data fields include a backward offset data field, the backward access flag referencing the backward offset data filed.
6. The method of claim 2 wherein each flag of the series of flags has a one to one corresponding reference to each data field of the plurality of data fields.
7. The method of claim 1 wherein the series of flags are ordered from highest importance to lowest importance.
8. The method of claim 1 wherein the at least one header further comprises a plurality of elements that each contain a unique identification field, size and data fields.
9. The method of claim 8 wherein the at least one unique identification field corresponds to a forward access identifier and at least one data field follows the forward access identifier and includes a forward offset data field having an offset value relative to a position of a frame being displayed or a start point of a media file.
10. The method of claim 8 wherein the at least one unique identification field corresponds to a backward access identifier and at least one data field follows the backward access identifier and includes a backward offset data field.
11. The method of claim 10 wherein the backward offset data field has a pointer to a previous key-frame block.
12. The method of claim 10 wherein the backward offset data field has a value corresponding to a previous key-frame time code.
13. The method of claim 1 , wherein the frame metadata within the plurality of data fields identifies at least one downloaded frame of encoded video.
14. The method of claim 1 , wherein the frame metadata within the plurality of data fields classifies at least one downloaded frame of encoded video.
15. The method of claim 1 , wherein the frame metadata within the plurality of data fields includes at least one identifier and a set of metadata data bytes.
16. The method of claim 1 , wherein the frame metadata is metadata describing the content of the frame.
17. The method of claim 1 , wherein the frame metadata is a content filtering metadata.
18. The method of claim 1 , wherein the frame metadata defines an alternative segment for presentation.
19. The method of claim 18 , wherein the pre-defined presentation rules display an alternate segment in place of a default segment.