DivX Plus HD

DivX Plus HD was launched in 2009 and is the brand name for the file type that DivX, Inc. has chosen for their high definition video format. DivX Plus HD files consist of high definition H.264/MPEG-4 AVC video with surround sound Advanced Audio Coding (AAC) audio, wrapped up in the open-standard Matroska container, identified by the .mkv file extension. DivX Plus HD files leverage and extend on Matroska's ability to support multiple language tracks, subtitles, chapters, and additional bonus content.

As of the release of DivX 7, DivX Plus HD support has been included in the main software bundle.

On 16 March 2010, DivX released DivX Plus Software (version 8) for Windows which included:

DivX has defined profiles which are subsets of MPEG-4/AVI and H264/MKV standards. Because the grouping is a specific subset of what is in the standards, there are certification processes for each of the profiles that device manufacturers must follow. Below is the DivX Plus HD profile.

All DivX Plus HD certified devices bearing a DivX Plus logo will adhere to the profile outlined in the table below, as would any tools that support the DivX profiles. DivX Plus HD devices are also tested for compliance against the DivX HD 1080p profile for MPEG4/AVI certification in order to maintain backwards compatibility

1280×720×60

NAL: 24000000

DivX has introduced additional features beyond the Matroska specification that are implemented during the video file creation process and exposed during playback in DivX Plus software and on consumer electronics devices certified for DivX Plus HD. Below are the standard and extended MKV features that are specific to the DivX Plus HD profile.

Currently, font files can be easily attached to .mkv files using a Matroska mux, but certain problems may arise when attempting to utilize a font during playback. Usually, performance is affected because the font file can be large and take time to load for the subtitles. The DivX Plus Word Fonts extension attempts to solve this problem by optimizing the font file during the file creation stage. A DivX Plus mux, like the DivXMKVMux, can examine the subtitle file, determine which characters are required from a font file, and repack the font file for attachment with only the necessary symbols, thereby reducing the font attachment size and decreasing the time it needs to load.

DivX has released a specification for a DivX Plus extension that aims to improve seeking quickly through a video file, either forward or backward. Called Smooth FF/RW, the creator of the video creates a lower resolution version of the video that is attached to the .mkv file and leveraged whenever a user instructs their player to seek fast forward or rewind. When the user presses fast forward or rewind, the full resolution track is swapped out with the lower resolution version, requiring less resources; when the user presses play, the lower resolution track is instantly swapped out to the full resolution version, which is intended to solve inaccurate seeking issues or a stuttering effect during fast forward and rewind.

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