UM:Dvo Effects Dvo Noise

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DVO Noise


DVO Noise is designed to manage and reduce unwanted analog electronic noise problems in video content.

The processing is done in field mode to address tape and transmission related problems.

The tool is organised into three sections :

  • Processing - specific processing options
  • Key - keyer settings for chroma adaptation
  • Setup - settings for various processing selections

DVO Noise utilises a process that adaptively selects the best mix of spatial and temporal (recursive) filtering for each pixel.

The default settings are a good start point for analog noise reduction. Adjust as required.

Temporal Filtering

The temporal (or recursive filtering) is the most effective filter in terms of reducing noise.

Temporal Strength


Use the numeric sliders to set the amount/level of temporal recursive filtering in each component.

Y, U and V components are treated independently.

Range 0 - 15
Default Y,U,V : 6, 8, 8

Avoid settings greater than 11-12 except for extreme situations. Also note that both Chroma Trim and Luma Trim (see below) will add their values to these set strengths.

Temporal Global


DVO Noise is an adaptive noise reducer. This means it disables the temporal/recursive processing of all moving edges within the image to assist in the reduction of motion artifacts.

Temporal Global enables filtering of the whole picture regardless of motion for maximum temporal filtering.

Default OFF

Temporal global should normally be set to Off and only enabled in extreme situations (or to create a motion smearing effect).

Enabling Temporal Global might cause excessive smearing in the picture.

In addition to the above controls, the motion sensitivity control on the Setup section adapts the temporal filtering in respect to noise size and intensity.

Spatial Filtering

Edge-preserving spatial filtering complements the adaptive temporal filters by processing noise in portions of the image that are detected as being in motion, while leaving non-moving areas unaffected.

The spatial filtering is done before application of the temporal filters and works in unison with the motion processing.

Spatial Strength


This is the overall level of spatial filtering applied in each channel.

Y, U and V components are treated independently.

Range 0 - 15
Default Y,U,V : 6, 10, 10
Spatial Size


The Spatial Size drop-down lists adjust the spatial size of the noise (in pixels) for each component.

Values 1,3,5,7,9
Default Y,U,V : 5, 9, 9

Chroma spatial size is normally larger due to subsampling and PAL/NTSC color technique.

Spatial Threshold


The Spatial Threshold determines when to filter, depending on the intensity of the surrounding pixels.

If there is a high enough intensity/contrast (e.g. an edge) between the noise and surrounding pixels, filtering will not occur.

Range 0 - 100
Default Y,U,V : 11.8, 23.6, 23.6

A low setting will only affect low intensity pixels (flat areas). A high setting will start to affect high intensity pixels (edges).

Spatial Global


This enables filtering of the whole picture by switching off the motion adaptation.

A moderate level of global spatial filtering can be used as a basic level of grain and noise reduction before using the temporal filtering (also see Global Balance).

Default OFF

This may cause excessive softening of the picture if the spatial filter is not set up correctly.

In summary :

Temporal filtering works in areas with no or little motion.

Spatial filtering works in areas of motion.

Global enable the filters to work on the entire picture.

Optimising the Spatial Filter
  1. Set Spatial Strength, Size and Threshold to their maximum
  2. Turn Spatial Global on
  3. Adapt the spatial filter to the grain/noise size by decreasing the spatial size settings to as low as possible while still removing noise
  4. Decrease spatial threshold until edges are not affected (a typical setting is  between 8-25%)
  5. Decrease spatial strength until the desired level of spatial filtering is achieved
  6. Decide whether Spatial Global should be left on (filtering of the whole picture), or turned off (filtering only in areas with motion).
Chroma Trim


The Chroma Trim controls are used to adjust the noise reduction on each selected colour. This allows for boosting or reducing both the spatial and temporal filter settings within the selected colour.

Range -8 to 7
Default 0

The colours 1, 2, 3, are selected via the Key page, as described in the Chroma Adaptation section below.

NOTE Having a temporal strength of 7, setting up Chroma Adaptation for a red colour and corresponding trim to +2, will set the temporal strength to 7 + 2 = 9 for areas in the picture that contain the selected red colour.
Luma trim


The Luma Trim control works in conjunction with the Luma Profile controls in the Setup section.

Having selected the mode and luma thresholds in the Setup section, use the Luma Trim control to adjust the noise reduction levels equally for the Y component in high lights (High) or low lights (Low). 

Range 0 - 7
Default 0

NOTE Having a temporal strength of 7, setting up Luma Profile to high and the Luma Trim to +2, will set the temporal strength to 7 + 2 = 9 for high lights.

Processing is slower using trims. Even if Temporal/Spatial strengths are at 0, Luma Trim will still add to this and result in processing within high lights or low lights.

Out Mix


The Out Mix control determines the percentage mix between the processed image (with noise removed) and the input image to give the final output image.

The default value of 100% results in an output with full grain removal, whilst a setting of 0% results in an output equal to the input image. 

Range 0 - 100
Default 100

This makes it possible to mix in some of the original noise into the processed picture.

Global Balance


Global Balance allows a combination of the basic level of spatial filtering and motion adaptive spatial filtering.

Maximum filtering according to spatial strength is achieved in areas with motion.

The Global Balance slider allows you to to set a minimum level of spatial filtering, rather than having the level set entirely based on motion detection. If the slider is set to 0, then parts of the image with no motion will receive no spatial filtering.  Increasing the slider increases the spatial filtering of areas with little or no motion. 

Range 0 - 100
Default 40
Motion Estimation


DVO Noise is a fully motion compensated noise reducer. This means that much more aggressive settings can be used without introducing smearing.

Values Off , Normal , Best
Default Normal

The Best setting is good for fast motion but is slower than Normal. In almost all cases, Normal or Best should be used.

Key (Chroma trim)

The Key (chroma adaptation) function can be used to adjust the levels of noise reduction in user-selectable colour regions.

As an example, this feature can be used for greater noise reduction in sensitive areas such as a blue sky, or less noise reduction in skin tones.

Three independent channels of chroma adaptation (labelled 1,2 and 3) allow adjustment of noise reduction levels (both spatial and temporal) in the regions of the selected colour.

Only colours with a saturation higher than approximately 5% will be detected.

Use the Key screen to adjust the hues and widths to isolate the colours in each channel:


Click a colour picker toggle button to enable/disable colour picking from the displayed monitor image:

Enable picker DVO-Noise-chroma-picker-enable.png
Pick area of colour from image using the mouse DVO-Noise-chroma-picker-pick.png

You can also select the hue by clicking on the hue bar with the left mouse button and dragging the hue bar left and right :

Drag on hue bar and/or orange box indicators to alter hue selection.

After selecting the colours in the Key controls, the corresponding Chroma Trim control in the Processing section may be used to adjust the grain/noise reduction for each selected colour. Chroma Trim allows for the boosting or reducing of both the spatial and temporal filter settings within the selected colour.

Even if Temporal/Spatial strengths are at 0, Chroma Trim will still add to that number and resulting in processing within selected colour.


The Setup section allows various other effect parameters to be configured.

History Required


The DVO Noise tool is recursive.

Recursive means the result for any given frame depends on the result of the previous frame(s).

For best results a certain amount of frame history needs to be built up, and this numeric slider is used to specify how many frames of history to use.

Range 0 - 15
Default 5 frames
Use Handles


The Use Handles button controls whether the history includes available handles of a scene/shot.

Normally, the history frames accumulated will terminate on a shot edit/event (start/end edit). There may be extra frames available (handles) before or after the start and end edit points of a shot however and these will be included as history if Use Handles is set.

Default ON

If handles exist, full and precise processing will be available from the first frame of a clip.

Motion Sensitivity


Motion sensitivity adapts the temporal filtering with respect to noise size and intensity. This control allows you to set the level of sensitivity.

Values Low, Medium, High
Default Medium

Motion sensitivity has a large impact on processing and the type of filter (spatial/temporal) being used.

It may be better to set Motion Sensitivity to Low rather than just increasing filter strengths.

Spatial Filter


Spatio - Temporal

Enabling this extends the spatial filter to become a 3D spatio-temporal filter, by including the use of temporal taps. This can enhance the noise reduction achieved. 

Default ON
Temporal Mix

The temporal mix controls the balance between the spatial and temporal taps of the spatio-temporal filter. 

This setting affects the noise reduction achieved by the spatio-temporal filter, with more noise reduction for the higher settings.

For fast motion material and a higher than default spatial filter threshold setting, a high temporal mix setting may increase the probability of artifacts. In such cases, this setting may be lowered. For a lower than default spatial filter threshold setting, the Full setting may be used.

Values Low, Medium, High, Full
Default High

The default setting High should be safe in most circumstances.


Spike enhances the spatial filter performance by incorporating a spike adaptation which relates to the grain/noise characteristics.

A low setting (e.g. Narrow) is suitable for smaller noise sizes and/or less pronounced variations in amplitudes.

A high setting (e.g. Wide) is suitable for larger noise and/or more pronounced variations in amplitudes. 

Values Off, Narrow, Medium, Wide
Default Narrow

Setting Spike to Narrow in conjunction with setting Motion Sensitivity to High and Motion Estimation (in the Processing group) to Best can help avoid motion estimation errors caused by very noisy material.

Luma Profile


Luma Profile allows the user to select the amount of noise reduction (both spatial and temporal) applied to the high lights or low lights within the image.

  • Low - more noise reduction in low lights
  • High - more noise reduction in high lights

Values Low, High
Default Low

Having selected the mode, you need to set the Luma Trim level on the Processing group (see above). This will adjust the noise reduction level in the Y component in high lights or low lights.

Luma Thresholds

The range of luminance values affected by the Luma Trim can be set by two Luma Thresholds. These two thresholds determine the point in high lights and low lights where the Low or High trim is at a maximum.

The effect of the Trim will gradually decrease between these two points. 

Luma Threshold Low
Range 0 - 50
Default 0% Luma
Luma Threshold High
Range 50 - 100
Default 100% Luma

Luma Trim level in Low mode
Luma Threshold Low adjustment

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