LEAD MPEG-4 Encoder User Interface

The LEAD MPEG-4 LEAD MPEG-4 is a DirectShow filter for compressing/decompressing video data usingthe MPEG-4 (ISO/IEC 14496-2) standard. MPEG-4 is suitable for a wide range of bandwidths, from low bandwidth to broadband.DirectShow filter for compressing/decompressing video data usingthe MPEG-4 (ISO/IEC 14496-2) standard. MPEG-4 is suitable for a wide range of bandwidths, from low bandwidth to broadband. Encoder is a  DirectShow Ò filter for compressing video data using the MPEG-4 (ISO/IEC 14496-2) standard. MPEG-4 is suitable for a wide range of bandwidths from low bandwidth to broadband. In addition to MP4 files, MPEG4 compressed video data can be stored inside AVI or OGG files with the option of saving the file with or without the audio data.

Key Features:

LEAD's MPEG-4 video codec A COmpressor combined with a DECompressor, or encoder Also known as compressor, this is a module or algorithm to compress data. Playing that data back requires a decompressor, or decoder. and a decoder, which allows you to both compress and decompress that same data. is a multimedia compressor / decompressor that registers into the Windows® collection of multimedia drivers and integrates with any application using DirectShow . Existing video software, such as Windows® Media Player® and Ulead Media Studio®, can utilize this codec to play, create and edit industry standard (ISO/IEC 14496-2) MPEG-4 streams.

Options for the LEAD MPEG-4 Encoder can be set manually through the encoder property page, which is shown in the figure below:

Changes will be applied only when filter’s state is stopped with the ability to set them permanently by selecting Apply or OK, or to abandon changes by selecting Cancel. Positioning the mouse pointer over a control displays general information for that control.

If you are using the encoder with a third-party software package, refer to your software’s documentation for information on how to access the encoder’s property page(s).

The following table shows the controls and their descriptions:

 

Control

Description

Compression Group

Quality Factor drop-down list box

The desired quality factor. The lower the quality factor, the better the quality. Possible values range from 1 (best) to 31 (worst).

Quantization type drop-down list box

The type of quantization to be used. Possible values are:

 

Value

Meaning

 

Linear

Use H.263 quantization.

 

Non-linear

Use MPEG quantization.

Output group

Frame rate drop-down list box

The desired output frame rate, in frames per second. Possible values are:

 

Value

Meaning

 

Input Frame Rate

Make the output frame rate the same as the input frame rate.

 

A value from 1.0 to 30.0

Use the specified output frame rate in frames per second.

Format drop-down list box

The encoder output type.  Selecting the LEAD proprietary subtype, LMP4, enables the usage of super compression. Possible values are:

 

Value

Meaning

 

mp4v

Make the encoder output type the Standard MPEG4 video media subtype.

 

LMP4

Make the encoder output type the LEAD proprietary MPEG4 video subtype. This allows super compression to be used.

 

XVID

Make the encoder output type the XVID MPEG4 video subtype.

Super Compression check box

Enables/disables super compression. This is valid only with the LMP4 output type (format). When super compression is used, compressed video size is reduced noticeably with almost the same quality, and the encoding and decoding speed is enhanced.

Files generated using this option will not be MPEG4 compliant: they can be decoded only by the LEAD MPEG4 Video Decoder.

Group Of Pictures group

No. of Ps between 2 Is drop-down list box

The number of P frames between two successive I frames [1].

No. of Bs between 2 Ps drop-down list box

The number of B frames between two successive P frames[1], [2].

Group Of Picture size static text

The expected output GOP size.

 

Motion Estimation group

Search option drop-down list box

Predefined values for the dimensions of the search block used when determining if motion is occurring. Selecting “Custom” enables the Search Width and Search Height spin edit boxes and is selected by default. Possible values are:

 

Value

Meaning

 

Fast

(8x8)

 

Normal

(16x16)

 

Slow

(24x24)

 

Very Slow

(32x32)

 

Custom

width 16 height 16

Search width spin box

The search block width and height used when determining if motion is occurring. The larger the block, the slower the encoding process. It is not recommended to use large values. The range is from 2 to the video stream The portion of the file holding the video data. The video data might be compressed to save disk space. The data has to be decompressed using a video decompressor before you can play (see) it. width, in pixels.

Search height spin box

The search block width and height used when determining if motion is occurring. The larger the block, the slower the encoding process. It is not recommended to use large values. The range is from 2 to the video stream height, in pixels.

Motion algorithm drop-down list box

The algorithm to be used when determining if motion is occurring. Possible values are:

 

Value

Meaning

 

Full Search

Use the full motion search algorithm (testing all possibilities). This option slows down the encoding process considerably.

 

Fast Search

Use fast motion search.

Four vector motion check box

If selected, the encoder will use four vectors in the motion estimation algorithm. Otherwise, one motion vector is used. When 4 vectors are used the quality is better, but the encoding is slower.

Half pixel motion check box

If selected, the encoder will use Half-Pixel accuracy (faster encoding); Full-Pixel accuracy is used otherwise.

 

[1]  To increase compression performance, MPEG4 uses Temporal Compression. Temporal compression is achieved by only encoding the difference between successive frames instead of the frames themselves. This means that frames cannot be considered in isolation. A given picture is constructed using prediction from a previous picture. An MPEG-4 video stream is comprised of I Frames, B Frames and P Frames, which are described as follows:

 

[2] To generate files that work with the QuickTime player, set this value to 0. Currently the QuickTime player does not support playing files with B frames. LEAD MPEG4 Decoder plays files that have B frames.