3ivx MPEG-4 Video & Audio
News Technology Download Store Company Company

3ivx DirectShow Media Muxer

Back to Support

The 3ivx DirectShow Media Muxer combines MPEG-4 Video and Audio streams into an MP4 file. It supports multiple audio and video tracks with Variable Frame Rates and positive or negative Offsets. The muxer supports MPEG-4 Video encoded by many different MPEG-4 encoders, including 3ivx D4 4.5, DivX 4, 5 and XviD.

The Media Muxer can repair some non-compliant MPEG-4 bitstreams, by rebuilding or correcting the video header information and unpacking packed B-Frames when necessary.

3ivx D4 4.5 for Windows - DS Media Muxer

Configuration Options

Optimize and Make Streamable
When checked the muxer will reorder the final bitstream so that the header information is at the beginning as well as interleaving the audio/video payload to minimize seeking, thus producing a streamable MP4 file. The process of reordering and interleaving can take a while as the entire file needs to be rewritten. This can cause an application to not respond (or pause). The duration of the pause is approximately as long as the time needed to duplicate the file. Recommended

Compress NVOPs
Replaces NVOPs with MP4 Dropped Frame Encoding resulting in a smaller file size and compatibility with MP4 Tools that do not support NVOPs. Recommended

Compress MOV Headers for Fast-Start
If checked when writing a MOV file the muxer will recursively compress the video headers using the gzip algorithm. This can dramatically reduce the header overhead of a file, and decrease the pre-load time when progressively downloading a MOV. Header Compression is compatible with QuickTime 3 or later. Recommended

Providing the muxed MPEG-4 Video and Audio streams are MPEG-4 compliant, or can be corrected, the resulting MP4 files will be compliant and are capable of being played back by MPEG-4 players such as the 3ivx D4 4.5, Apple QuickTime 6, Philips Platform4 player and EnvivioTV.


Pixel Aspect Ratio (PAR) Modification
Pixel Aspect Ratio is the ratio of a pixel's width to its height. The Pixel Aspect Ratio (PAR) setting allows the encoding of anamorphic videos. An anamorphic video is video where the pixels are not square.

The PAR List Box can be used to configure the PAR of the pixels encoded. Normal computer pixels are square pixels (1:1 PAR). DVDs and other video sources tend to use non-square pixels and will either need their pixels scaled to square pixels before encoding, or the pixels can be encoded, but have their PAR set.

The PAR menu lists Square Pixels, the 4 common Video PARs (as found in DV and DVD sources), as well as the SVCD PARs. There is also an extended option which can be used to specify virtually any PAR.

The 3ivx decoder only decodes non-square PARs correctly when playing an MP4 file, so the bitstream must be muxed into an MP4 File for the effect to be realized. Not all MPEG-4 decoders currently support PAR, thus they might produce the wrong aspect.

Cropping the pixel matrix will not affect the PAR. The default is Square Pixels.

More In-Depth information about PAR and why it is useful is available here.

PAR Width
Specifies the relative width of a pixel when using Custom PAR (1..255). The default is 1.

PAR Height
Specified the relative height of a pixel when using Custom PAR (1..255). The default is 1.


Support > Windows > Encoding > DS Media Muxer Properties

Site Map  |  Contact Us  |  Job Opportunities

Copyright © 2011 3ivx Technologies Pty. Ltd. All rights reserved.