Systems and methods for seeking within multimedia content during streaming playback

A playback device comprising:

• a processor;
• a memory;
• and
• a network connection, wherein the memory contains a playback client for causing the processor to perform the steps of:
• obtaining, using a file parser, an index to a selected media sequence that is contained within a media file, wherein the playback client comprises the file parser, a download manager, and a playback engine;
• identifying, using the playback engine, media required to play the media sequence from a starting location;
• converting, using the file parser, the identified media required to play the media sequence from the starting location into at least one byte range of the media file;
• providing, using the file parser, the at least one byte range of the media file to the download manager;
• requesting, using the download manager, the identified media via the network connection of the playback device using the at least one byte range of the media file;
• receiving, using the download manager, the identified media via the network connection of the playback device;
• buffering, using the download manager, the received media pending commencement of playback;
• maintaining, using the download manager, a mask indicating the buffered media;
• playing back, using the playback engine, the buffered media;
• receiving, using the playback engine, a seek instruction via a user interface;
• determining, based on the mask, at least one particular portion of media that has not been buffered at the playback device and that corresponds to media required to play the media sequence in accordance with the seek instruction;
• providing a flush request to the download manager;
• flushing a previous request for a byte range of the media file by closing a connection with a remote server using the download manager in response to the flush request;
• and
• requesting, from a remote server using the download manager, the determined at least one particular portion of media that has not been buffered at the playback device.

A playback device comprising:

• a processor;
• a memory;
• and
• a network connection, wherein the memory contains a playback client for causing the processor to perform the steps of:
• obtaining an index to a selected media sequence using a file parser, wherein the playback client comprises the file parser, a download manager, and a playback engine;
• instantiating a remote file object and a partial file object, wherein:
• the remote file object handles communications associated with requesting portions of media from a remote server and maintains a queue of requested portions;
• and
• the partial file object handles storage of the portions of media received from the remote server and establishes a temporary data path for a data file for the media sequence;
• requesting, using the download manager, portions of media required to play the media sequence from a starting location via the network connection of the playback device;
• maintaining a queue of requested portions of media, wherein maintaining the queue comprises flushing the request for at least one previously requested portion upon determining that the at least one previously requested portion of media is no longer required;
• receiving, using the download manager, the requested portions of media via the network connection of the playback device;
• buffering, using the download manager, the received portions of media pending commencement of playback;
• maintaining, using the download manager, a mask indicating the buffered portions of media;
• playing back, using the playback engine, at least one of the buffered portions of media;
• receiving, using the playback engine, a seek instruction via a user interface;
• when at least one previously requested portion of media is no longer required, flushing a request for the at least one previously requested portion of media using the download manager, wherein flushing the request for the at least one previously requested portion comprises closing a connection with a remote server associated with the flushed request;
• identifying, using the download manager and based upon the mask, at least one particular portion of media corresponding to media required to play the media sequence in accordance with the seek instruction that has not been buffered at the playback device;
• and
• requesting from the remote server, using the download manager, the at least one particular portion of media required to play the media in accordance with the seek instruction.