DivX Help Guide
DivX Version 5.0
Document revision 1 (2002-03-03)
Written
by: Darrius "Junto" Thompson and the Members of DARC
About this Document
This page gives a detailed overview of the various features of
the DivX™ 5.0 Codec and the DivX Pro™ 5.0 Software.
Introduction
DivX 5.x is the highest-quality, highest-performance and most
advanced video technology available today. DivX 5.0 redefines the
video state of the art and introduces new technologies and tools
that make it easier than ever to create the highest quality video
available at incredible file sizes. It also unveils a brand new,
professional-grade version, DivX Pro. The next generation is here.
Read more about all the new features in DivX 5.0. It features
Feature Comparison
Performance measured with full screen resolution,
software-based performance on top-of-the-line hardware. Note: The
DivX codec and its features are independent of applications and can
be used by any application that supports a common video interface
such as the VFW interface.
DivX Decoder
Ensuring Decoder Performance
There are several things you can do to ensure your system is
prepared to play DivX content with optimal performance.
- Use the latest DivX Player application included in the DivX
Codec Bundle. The DivX Player is the official player application
of DivX video and is optimized to handle all the latest features.
- Use the DivX™ decoder filter with other player applications.
Many other Windows players use one of two methods to decode DivX
the "Video for Windows codec," or b) the "DivX decoder filter."
For speeds up to two times faster, make sure Windows Based Media
Players uses the DivX decoder filter for playback. The DivX
decoder filter is installed with the codec. To check, you can
access the filter from the start menu where you installed the DivX
codec. If it is not there you can do the following:
- Set your graphics acceleration to maximum in the display
properties
- Ensure that you are not running a video capture or TV tuner
application.
- Try switching the display depth. The filter usually does not
work in 8-bit color modes.
- Make sure you have the most recent drivers for your video
card
If nothing helps, it is recommended you switch to 16-bit display
depth, because it usually fastest when using the VfW codec.
Post-Processing
DivX post-processing is comprised of the horizontal and vertical
deblocking filters and the deringing filter. Post-processing is a
CPU-Intensive process, often burning more CPU time than decoding
itself. You may not want to post-process, especially if you prefer
the un-post-processed image, or if your PC is not powerful enough.
To cater to users' post-processing preferences, 6 different levels
of post-processing have been defined. At the minimum (level 0), no
post-processing algorithm is used; at the maximum (level 6) every
clever algorithm is used to enhance the appearance of your
video.
Since the human eye is less sensitive to the chrominance
components of a video signal and the more sensitive to the luminance
components only the luminance plane is processed at lower
post-processing levels, while higher levels activate the same
algorithms on the chrominance planes.
The post-processing algorithms used are activated in the
following order: deblocking on luminance planes, deblocking on
chrominace planes, deringing. You can adjust the post-processing
level by accessing the slider in the configuration dialog of the
DivX DirectShow filter, which can be accessed by launching the
post-processing filter from the start menu. You can do this by
running the decoder configure dialog box application from the
control panel (Start -> Programs -> DivX -> Decoder
Config).
De-blocking
The filter operates along the 8x8 block edges, on both the
luminance and chrominance color planes. It helps to reduce the
blocking artifacts caused by the DCT spatial compression algorithm
used by the codec.
Blocking is the most noticeable artifact, so this is the first
algorithm to be applied.
De-ringing
The de-ringing filter is used to eliminate noise near sharp edges
caused by the quantization process (the so-called Gibbs effect). The
noise is more noticeable in animations, where there are higher
frequency coefficients. The deringing on the luminance plane is
activated at post-processing level 6. Due to high CPU requirements
and relatively low impact of the filter, it is only turned on for
Pentium-III or newer processors.
Chart of post-processing levels
| Post processing level |
Horizontal deblocking luminance |
Vertical deblocking luminance |
Horizontal deblocking chrominance |
Vertical deblocking chrominance |
Horizontal deringing |
Vertical deringing |
| 1 |
 |
|
|
|
|
|
| 2 |
|
|
|
|
|
|
| 3 |
|
|
|
|
|
|
| 4 |
|
|
|
|
|
|
| 5 |
|
|
|
|
|
|
| 6 |
|
|
|
|
|
| |
DivX Encoder
DivX Codec Main Menu
Bitrate Modes
The DivX 5.x encoder has three possible modes.
- 1-Pass Variable Bitrate Mode. The encoder will aim at making
the average bitrate of a movie close to the specified value,
allocating less data for low-motion scenes and more data in
fast-motion scenes. You can either enter in the desired bitrate
manually or use the slider.
- 1-Pass Quality Based Mode. The encoder will code everything
with the same absolute quality without giving respect to the
amount of motion. When using this mode all frames receive the same
amount of compression, without regard to their complexity. While
it is not the best choice for making archives, it is a good idea
to use this mode when preparing content for future editing. It
guarantees the preservation of quality in all frames. When
selecting the "Quality Based" mode the slider will adjust the
Quantizer on a percentage basis while showing the exact number
that will be used to compress each frame.
- 2-Pass (Variable Bitrate Mode). Prior to encoding, the video
is analyzed to understand its complexity. We can then allocate
data more efficiently to scenes that need more and less data to
scenes that do not. This provides more accuracy than "1-Pass"
encoding. In this mode, the encoder will try to make the
subjective quality of the stream constant, and simultaneously
ensure that the complete stream size is close to the number
specified. Operation in this mode requires the video to be
processed twice. 2-pass encoding in independent from any
application you may use for encoding and can be used with any
program. If you want to encode a 2-hour show and be sure it fits
on a 650Mb CD, then this is the choice for you.
Two-Pass Encoding Log Files
During the first pass of "2-pass", encoding data is gathered that
will be reused at the second pass to increase accuracy and quality.
To reduce encoding time when choosing "2-pass" the encoding data can
be reused when there is a need to encode the same content in
"2-pass" mode with the same settings. Encoding time is reduced since
this will only require that the 2nd pass be performed. It is
possible that external applications be developed to manipulate these
logs for even more accurate adjustments in data allocation.
The "Protect Log/My File" setting will prevent the possibility of
accidentally overwriting any existing log files.
MPEG-4 Tools
B-frames/Bi-directional encoding
There are three types of frames that are possible within a DivX
video stream. These frames are called "I-frames" (Intra), "P-frames"
(Predicted) and "B-frames" (Bi-directional). Prior to DivX 5.0 the
only frame types were I and P. I-frames are encoded only using
information from within its own frame. It does not use any
information from other frames (temporal compression). An I-frame is
similar in concept to encoding a single frame using JPEG. P-frames
(Predicted) are forward predicted and may refer to either an I-frame
or P-frame. They are encoded from the frame that precedes it. In any
video sequence a group of frames will have many of the same images.
For example, if you were to watch a news anchorperson you'll notice
they barely move and the background would stay almost identical for
every frame. (Remember that there are commonly up to 30 frames in a
single second). So instead of encoding each one of those 30 frames
independently as you would in an image file such as a JPEG you can
exploit the redundancy of each frame by the use of P-frames.
Essentially a P-frame is a future frame that determines where a
block in the previous frame has moved to in it's current P-frame. So
instead of spatially encoding (JPEG) the frame the P-frame just says
"Hey the block in the previous frame has moved to location (X,Y)
which requires much less data then encoding each frame spatially.
Essentially we transmit the difference between frames which is more
efficient than transmitting the original I-frame.
DivX Pro 5.0 introduces the ability to also use "B-frames".
B-frames allow the DivX codec to predict frames from the future,
choosing the best prediction match among 2 prediction frames instead
of only one. B-frames are not only codec by using forward predicted
frames but also from backward predicted frames which can be an I or
P frame. Using B-frames reduces the amount of data needed to code a
frame and improves quality more specifically in areas where moving
objects reveal hidden areas.
Global Motion Compensation
Global Motion Compensation (GMC) helps to improve complex scenes
where zooming and panning are present. The ability to reduce the
required data from one frame to the next can be reduced since there
is a commonality within panning and zooming scenes that can be used
to more efficiently compensate for what is more normally a group of
blocks in such scenes.
Quarter Pel
As explained in the "B-frames" summary, data is reduced when the
difference between two frames (prediction error) is transmitted
instead of the entire image being sent. The difference in a
successive frames composition is generally computed on a
macroblock-by-macroblock basis (16x16 pels) or on a block by block
basis (8x8 pels). For example, a part of an image located in a block
at grid location (1,1) may move to grid location (1,2) in the next
frame. As you may realize an image in one block will likely need
more accuracy than just the ability to move on a limited block by
block basis with an accuracy that is limited to an integer pixel
unit (1,1). DivX has increased the previous accuracy of using a half
pel (1.5, 1.5) to include the ability of using "Quarter Pel" (1.25,
1.75) accuracy with the Codec release. Quarter Pel performs a
specific filtering on each block to produce a virtual block that
should represent how the original block should appear if it is moved
a 1/4 of a pixel unit.
MP4 File Creator
Clicking on this checkbox will allow you to write an MPEG-4
compatible file as your video output.
Quick Config CLI
See the Quick Config
CLI Appendix for more information on this feature.
General Parameters Menu
Enable Crop
Cropping is commonly used to remove un-needed borders, which may
take up un-needed data. This is seen commonly in "Widescreen Format"
or "Letterboxed" movies. It is also common to see borders within
content that are completely unnecessary or are in place due to poor
encoding of the source material. Cropping will remove or "crop" any
borders not desired. Just specify amount of pixels to crop each
border by.
Enable Resize
Resize allows content to be encoded at a specified resolution.
There are many target applications and environments suitable for
using the DivX codec and the content should be appropriately encoded
for these environments. Generally the smaller the resolution the
lower the file size. The output resolution can be adjusted so that
it preserves the original resolution, or so that it changes the
resolution for applications that might require much smaller
resolutions and bitrates, such as video conferencing or browser
based videos. There are 4 options for "Resizing":
- Bilinear (Very Soft)
- Bicubic (Soft)
- Bicubic (Normal)
- Bicubic (Sharp)
From a mathematical viewpoint, it could be argued that the
bicubic resize algorithm is best for enlarging the image while
bilinear is more suited to size reduction. From our own experience,
the opposite appears to be true - bicubic gives the best visual
quality for reducing the video resolution. The bilinear algorithm is
slightly less CPU intensive and will allow the codec to run faster.
The choice of algorithm is very much up to personal preference.
Psychovisual Enhancements
By exploiting what we know about the Human Visual System (HVS) we
have increased the efficiency of allocation video data helping to
increase the perception of quality in video. For example, if the
human visual system has very low sensitivity to a specific type of
characteristic in an image we may decrease the amount of data
located at this location and re-allocate this data to a location
within an image where the human visual system is much more
sensitive. The Psychovisual enhancements are applied to both a frame
and macroblock basis. One of the important factors in evaluating
Psychovisual Modeling is to NOT just compare a single frame but to
compare a full sequence. An image may look worse or better when a
single frame is examined but the key to reducing data is to reduce
data in a way that the human visual system does not notice over a
video sequence running at a full frame rate (e.g. 30 frames per
second). Psychovisual modeling is a fairly new field when applied to
real videos or movies. This area is full of possibilities we have
only just started on and will continue to explore.
Pre-Processing
Video noise is often referred to as "specks", "snow", or "hair"
within a video (i.e. "snow" that is visible when watching TV over an
antenna"). Any number of the processes of video production and
distribution can add noise into the video. Some of the worse video
noise can be seen in old or poorly recorded movies. Noise can be a
big problem when it comes to compressing the video as the noise
consumes a large proportion of the bits available for wanted
video.
The preprocessing filter uses digital signal processing
techniques to remove the noise from the source material prior to
encoding. Broadly, there are two classes of filter that can reduce
noise: temporal and spatial. To explain how they work, let's
consider a single pixel somewhere in the image. Spatial filtering
looks at the neighborhood pixels within the pixel's own frame and
applies a smoothing, or low-pass function. A temporal filter
smoothes pixels at the same position over a few consecutive frames
to reduce the effect of noise. By using these techniques to reduce
noise prior to video encoding we can, in certain content, increase
our compression ration and improve quality.
There are 4 settings for preprocessing:
- Light
- Normal
- Strong
- Extreme
As with all features there is a particular content that may be
affected more than others. Generally old noisy content can see
dramatic effects in file size reduction and quality. Normal
pre-processing should not introduce any visual degradation of the
source file, however we have provided a "Light" setting for very
tricky source, the "Strong" and "Extreme" settings will wash the
source a little, however it will remove the most amount of data and
should be used when file size is more important than quality.
Keyframe
The DivX encoder will automatically insert a key frame every time
it detects a scene change. However, long interval between scene
changes are possible, and when they occur, the encoder automatically
inserts keyframes with user specified frequencies. Keyframes are the
largest of all frames, so the frequency of their placement can have
a drastic effect on the encoded file. We have found 300 frames to be
the maximum interval the encoder should go without inserting a
keyframe. This corresponds to at least one keyframe every 10 seconds
in a 30 fps stream. Also, depending on the player used, the maximum
key frame interval may determine the maximum interval for seeking.
This occurs when players are designed to seek to "I" or keyframes.
Reducing the keyframe interval can also improve delays and the
quality of streaming content.
Intelligent De-interlace/Inverse Telecine (Source
Interlace)
Interlacing, invented in the 1940's, is probably the earliest
form of video compression. Instead of transmitting a complete video
frame 60 times every second, engineers discovered that they could
halve the bandwidth needed by the TV signal if they sent alternately
odd and even "fields", each field comprising just the odd or even
picture lines. Interlacing is most commonly found on material
intended for TV broadcast, or material created by consumer
camcorders.
Interlacing is not a problem if it is correctly displayed on an
interlaced display device, i.e. a television. An interlaced video
camera running at 30fps captures the odd-numbered lines of a frame
in 1/60th of a second, and the even-numbered lines in the next
1/60th of a second. When viewed on a progressive display device,
such as a PC, two fields are interlaced to create one frame. Because
half the frame's lines are captured a fraction of a second later
than the other half, fast-moving objects may appear jagged, the
result of the object advancing slightly within 1/60th of a second.
The "progressive" format is preferred for PC playback since the
entire frame is captured each second and no de-interlacing will be
required.
It is possible to remove the jagged-edge interlace artifacts by
applying a process known as "de-interlacing" to the video. The DivX
codec is able to de-interlace the source video prior to encoding.
For this to work correctly, it is important that the video has not
been resized vertically external to the codec. Resizing within the
codec does not affect the operation of the codec's
de-interlacing.
Inverse-Telecine, or "IVTC", is applicable to cinematic film that
was transferred to NTSC video. Film is usually photographed at 24
frames per second (fps), whereas the NTSC standard is 30 fps. The
film-to-video conversion (called "telecine") duplicates some video
fields to bring the film input to the NTSC frame rate.
Theatre-release films transferred to video for the American
continents, for example undergo the telecine process. IVTC is the
process of removing the duplicate fields inserted in the telecine
process.
The DivX™ codec has three main options for de-interlacing and
IVTC:
- "All frames are progressive" - This is the default setting
where de-interlacing and IVTC are never used. It is suitable for
material that is already in a progressive format.
- "All frames are interlaced" - The codec will use an adaptive
algorithm to deinterlace every frame prior to resizing and
encoding. The video should not be cropped or resized prior to
encoding. Resizing within the codec will cause no problems.
- "Intelligent IVTC/deinterlace" - With this setting, the codec
automatically determines whether to enable IVTC and deinterlacing
as appropriate to the material being processed.
- Only the MP4 file output is active, the encoding application
writes a dummy file
- The video should not be cropped or resized prior to
encoding. Resizing within the codec will cause no problems.
- A further deinterlacing option is available for users whose
main concern is encoding speed: "Basic Video Deinterlace". This
option should not be used when resizing. Select the first Source
Interlace option, "All frames are progressive" when using the
"Basic Video Deinterlace".
Advanced Parameters Menu
Data Rate Control Parameters (RC)
The DivX Codec uses a patent-pending dual asymmetric rate
control. It uses dual period control loops to achieve a best balance
reacting and adjusting to the variations in a short time sale while
controlling and averaging the bitrate in the long time scale.
Essentially, it is well balanced as it adapts dynamically to the
content of the scene, providing optimal allocation of bandwidth. It
is flexible and easily adjustable for different application
scenarios. The creation of the DivX Rate Control algorithm comes
from testing many real full-length movies against the DivX codec in
multiple user environments (i.e. TV, PC, PDA, etc.).
There are several settings that may be experimented with. We
highly recommend that only experiences users change these settings
since minor changes can cause significant effects.
Maximum and Minimum Quantizers
The quantizer is one of the most important parameters in video
coding. The quantizer controls how fine the encoder codes the video
sequence. The rule of thumb is: for the same frame, a smaller
quantizer equals better quality and higher bit consumption while a
larger quantizer equals lower bit consumption and inferior quality.
Since every frame has a different amount of complexity a subjective
equality in quality can be seen among different frames even with the
varying quantizers. Basically, the quantizer operates the rate
control. Balancing the quality of video with bit consumption can be
quite an art form.
Note: RC settings are truly "for the adventurous souls". These
default settings should give near optimum results.
RC Averaging
RC Averaging controls how fast the RC forgets the rate history.
Larger values usually result in better higher motion scenes and
worse low motion scenes.
Rate Control Down/Up Reaction
RC Down/Up Reaction - control the relative sensitivity in
reaction to high or low motion scenes. Larger values usually result
in better high motion scenes, but larger bit consumption.
All these parameters are inter-correlated. The effect from their
setting is approximate and often depends on the settings of the
other parameters.
Data Partitioning
Data portioning may be useful in any situation where transmission
errors may occur, such as a streaming or broadcast environments.
Data Partitioning is a different way of organizing data in the
stream. A frame is composed of adjacent macroblock and each
macroblock usually includes motion vector (prediction) and texture
information. This allows the stream to be more resilient to
transmission errors, in this modality the motion vector and the
texture are separate (not interlaced with each single macroblock)
and grouped in video packets. Each video packet is and independent
entity inside the steam and can be decoded separately from the
others. Use of Data Partitioning can also permit the activation of a
series of tools that allows for error recovery and packet
resynchronization.
Performance/Quality
There are 5 settings available for Performance/Quality.
Essentially if more quality is desired more CPU is needed. There
should rarely be a time when you will need to pick any other quality
setting other than "Slowest" as it produces the BEST quality.
Accuracy in motion estimation is sacrificed at the to increase the
performance of encoding content. With today's CPU's and the
efficiency of the DivX Codec encoding at up to "Full Screen"
resolutions at real-time encoding speeds is possible. However lower
quality settings could be useful when there is not enough CPU power
and a sacrifice in quality can be justified. Generally, real-time or
faster than real-time encoding speeds are only necessary when
broadcasting real time video feeds, yet the faster the encoder the
lower the cost of encoding. Leave this setting at "Slowest" unless
otherwise necessary.
DivX MP4 Creator
The DivX MP4 creator converts a DivX AVI video file version DivX
5.0 or greater to a DivX video file encapsulated in the DivX MP4
file format. To use this feature select the DivX AVI file that
requires conversion from the "input" box. The default output
directory is the same as the source directory. The new file format
creator can also create a log file that may include information such
as type of frames, number of audio chunks, number of video chunks,
resolution and framerate. Once the appropriate file and directories
are selected the conversion can begin. The output DivX MP4 file will
not replace the original AVI file.
Manage Settings Menu
The settings manager allows commonly used settings to be easily
saved and accessed so that they may easily be reused at a later
time. This is useful for many reasons such as making sure the
settings are optimal for certain types of movies, decoding devices
or environments that only support certain MP4 features. Also, this
is extremely useful since it allows you to easily send anyone else
the exact settings you are using. To add your current settings just
click on "Add codec settings" and you will be able to name write a
description for this setting. If you would like to save the
settings, just select "Save settings to file" and if you would like
to load a new setting just select "Load settings from a file".
DivX™ Advanced Research Centre (DARC) Team
Digital Video Engineering Team
- Eugene "Sparky" Kuznetsov
- Andrea "e7abe7a" Graziani
- John "eagle" Funnel
- Adam "c0redumb" Li
- Mac® OS development by Adrian "AdrianB" Bourke
Management & QA
- Jérôme "Gej" Rota
- Darrius "Junto" Thompson
- Ben "TheKid" Côté
Copyright and Trademarks
The DivX Codec and DivX Pro Software are Copyright © 2002 DivXNetworks, Inc. MMX iDCT
and fDCT implementations are © Intel Corp., 1998-2000.
DivX and DivX Pro are trademarks of DivXNetworks, Inc.
Appendix
MPEG-4 Tools, Profiles and Levels
| Visual Tools |
Advanced Simple Profile |
Simple |
| Basic |
X |
X |
| I-VOP |
|
|
| P-VOP |
|
|
| AC/DC Prediction |
|
|
| 4-MV, Unrestricted MV |
|
|
| Error Resilience |
X |
X |
| Slice Resynchronization |
|
|
| Data Partitioning |
|
|
| Reversible VLC |
|
|
| Short Header |
X |
X |
| B-VOP |
X |
|
| Global Motion Compensation |
X |
|
| Quarter-Pel Motion Compensation |
X |
|
| Visual profile |
Level |
Typical visual session size |
Maximum bitrate (kbit/s) |
| Advanced Simple Profile |
L0 |
176x144 |
128 |
| Advanced Simple Profile |
L1 |
176x144 |
128 |
| Advanced Simple Profile |
L2 |
352x288 |
384 |
| Advanced Simple Profile |
L3 |
352x288 |
768 |
| Advanced Simple Profile |
L4 |
352x576 |
3000 |
| Advanced Simple Profile |
L5 |
720x576 |
8000 |
| Simple |
L3 |
CIF |
384 |
| Simple |
L2 |
CIF |
128 |
| Simple |
L1 |
QCIF |
64 |
DivX 5.0 CLI parameters
The command line interface parameters will be automatically
updated as you use the GUI to change the codec parameters. The
opposite is also true. When you type parameters into the CLI, the
GUI will show the changes after you press the tab or enter key. This
makes the CLI an easy shorthand for advanced users to use to manage
their settings.
MPEG4 Profile-mp Profile
profile= SP Simple Profile
ASP Advanced Simple Profile
SSP Simple Studio Profile
CSP Core Studio Profile
F Free
MPEG4 level-ml Level
Level= 1 Level 1
2 Level 2
3 Level 3
4 Level 4
F Level Free
Bitrate Mode-b1 Bitrate,[MaxBitrate]
Bitratemode= -b1 1 pass CBR mode
-b1q 1 pass Q based mode
-b21 2 pass 1st pass
-b22 2 pass 2nd pass
Examples:
-b1 780 1 pass followed by bitrate
-b1q 50%,1000 1 pass Q based followed by
a percent if %, The optional second
parameter is the Max Bitrate
-b1q 10.2 1 pass Q based followed by a Quantized
if nothing and < 31
-b21 800 2 pass 1st pass followed by bitrate
-b22 800 2 pass 2nd pass followed by bitrate
-b1 780,1500 The optional second parameter is the Max Bitrate
In 1 pass mode (-b1 and -b1q) the log and mv files section and
corresponding CLI entry are disabled.
Write MPEG4 file-ff "FileName" Write a MPEG4 file
Crop-c left,right,top,bottom
Resize-r width,height,Quality
Quality= 1 Bilinear
2 Soft Bicubic
3 Normal Bicubic
4 Sharp Bicubic
Pre Processing Source-pre [Strength] or [TemporalLevel,SpatialLevel,SpatialPasses]
Strength= 1 Light
2 Normal
3 Strong
4 Extreme
TemporalLevel= from 0.0 to 1.0
SpatialLevel= from 0.0 to 1.0
SpatialPasses= from 1 to 3
Psycho Visual Enhancements-psy [Strength] or [FrameLevel,MacroblockLevel]
Strength= 1 Light
2 Normal
3 Strong
FrameLevel= from 0.0 to 1.0
MacroblockLevel= from 0.0 to 1.0
Maximum Key Frame interval-key MaxInterval
Two pass encoding log and mv-log LogFileName -mv MVFileName
If -mv option is specified during 2nd pass the mv file will be used,
if no -mv option is specified during 2nd second pass, MV will be
recalculated
Protect log/mv file-p
Source Interlace/deinterlace-d Method
Method= 1 All Frames are progressive
2 All Frames are interlaced
3 Intelligent IVTC/deinterlace
-bvd
Basic Video Deinterlace
MPEG4 ToolsQuarter Pixel
-q
GMC
-g
Bi-directional encoding
-b
Data Rate-dr MaxQ,MinQ,RCAveragingPeriod,RCReactionPeriod,RCDownUpRatio
Example
-dr 12,2,2000,10,20
Scene Change Thereshold -sc SceneChangePercent
Example
-sc 50
-sc 70%
Data partitioning-dp PacketSize
Performance/Quality-pq Value
Value= 1 Fastest
2 Fast
3 Medium
4 Slow
5 Slowest
Bitrate Mode-b1 Bitrate,[MaxBitrate]
Bitratemode= -b1 1 pass CBR mode
-b1q 1 pass Q based mode
-b21 2 pass 1st pass
-b22 2 pass 2nd pass
Examples:
-b1 780 1 pass followed by bitrate
-b1q 50%,1000 1 pass Q based followed by a percent if %,
The optional second parameter is the Max Bitrate
-b1q 10.2 1 pass Q based followed by a Quantized if
nothing and < 31
-b21 800 2 pass 1st pass followed by bitrate
-b22 800 2 pass 2nd pass followed by bitrate
-b1 780,1500 The optional second parameter is the Max Bitrate
Max bitrate is not yet implemented in the DivX 5.0
Write MPEG4 file-ff "FileName" Write a MPEG4 file
Crop-c left,right,top,bottom
Resize-r width,height,Quality
Quality= 1 Bilinear
2 Soft Bicubic
3 Normal Bicubic
4 Sharp Bicubic
Pre Processing Source-pre [Strength] or [TemporalLevel,SpatialLevel,SpatialPasses]
Strength= 1 Light
2 Normal
3 Strong
4 Extreme
TemporalLevel= from 0.0 to 1.0
SpatialLevel= from 0.0 to 1.0
SpatialPasses= from 1 to 3
Psycho Visual Enhancements-psy [Strength] or [FrameLevel,MacroblockLevel]
Strength= 1 Light
2 Normal
3 Strong
FrameLevel= from 0.0 to 1.0
MacroblockLevel= from 0.0 to 1.0
Maximum Key Frame interval-key MaxInterval
Two pass encoding log and mv
-log [LogFileName]
-mv [MVFileName] If -mv option is specified during
2nd pass the mv file will be used
Protect log/mv file
Not functional in this release. | 
