UM:Dvo Effects Dvo Steady

From DigitalVision
Revision as of 13:59, 3 August 2017 by Alastair (talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Darrow-up.png     Previous Next

DVO Steady
Also see : DVO Steady II


DVO Steady is used to reduce unsteadiness due to film weave during scanning or camera shakes during capture of footage. A two pass solution, including advanced motion estimation, provides better separation of random instability and pan/tilt movements.

 

DVO Steady can be used for both film and progressive video material.

 

The two passes are :

 

ch-dvo_steady_menu

Analyze - data collection
Processor - actual processing

 

Analysis

ch-dvo_steady_menu

 

The first pass collects analysis data from the pictures. This is used in the processing stage.

 

The default settings work with most types of material, so just enable the Analyze control and let the shots be analyzed before processing takes over.

 

dv_note

A key frame is added for every analyzed frame containing the analysis data. Complete analysis of the selected clip(s) should be done before looking at the result and adjusting the processing parameters.

Mode, Size and Density

ch-dvo_steady_params_analyzer_mode

Mode

ch-dvo_steady_params_analyzer_mode-values

 

The analysis looks at the complete frame with selectable focus instead of locking to a single point. This has several advantages, especially in archiving/restoration applications with time constraints and problems like camera shake and film stretching.

 

The Mode control determines where the analyzer focuses within the frame.

 

Values :

Full, Centre Weighted, Border Weighted, Frame Only

Default :

Full

 

Full - Complete frame
Centre Weighted - Complete frame with priority towards centre
Border Weighted - Complete frame with priority towards borders
Frame Only - Only analyzes film frame edge (i.e. requires complete frame edges).
This is further specified by the "Frame Only Border Enable" controls.</br>

 

dv_note

Frame Only mode is fastest.

Size

Sets analyzer size, which should be related to image size and motion.

 

Values :

Small, Medium, Large

Default :

Medium

 

dv_note

Size affects processing time. The larger the size, the more processing required.

 

Size Setting

Suitable For

Small

SD - low/normal motion

HD/2K - low motion
Frame Only mode (any format)</br>

Medium

SD - normal/high motion

HD/2K - normal motion

Default

Large

HD/2K - high motion

4K - low/normal motion

Density

Determines the amount of analysis within the frame.

 

Values :

Small, Medium, High

Default :

Medium

 

Low - Lowest safety margin - less accurate
Medium - Normal safety
High - Increased safety margin, more accurate

 

dv_note

Processing time increases with the density.

Region of Interest

ch-dvo_steady_params_analyzer_roi

 

Set or find active area of picture - the region of interest to be analysed.

 

Values :

Disabled, Specific

Default :

Specific

 

Disabled - use complete frame
Specific - set region of interest via additional parameters below

ROI Size

This is the number of pixels from each edge where the frame (active area) starts.

 

Range :

0 to 2048

Default :

0 pixels

 

dv_note

Only borders which have visible “non-clipped" film frame edges must (can) be used and Region of Interest must be set to include those.

Processing

ch-dvo_steady_menu_processor

 

Processing parameters are applied to the pictures in accordance with the result from the analyze pass.

Basic Setup

ch-dvo_steady_params_processor_enable

Enable

This toggle button allows you to enable/disable the effect. By default, as soon as the effect is added it is applied/enabled

Colour

The drop-down list will default to the project setting for the input format. You need to set this control according to the material that you are working with. If the footage was shot with a video camera, select a linear format. If this control is not set correctly the material may not be processed properly.

 

Default :

From Project

Analyze

This toggle button enables the analysis function.

 

dv_note

Currently, once analysis is complete, it should be turned off to enable rendering.

 

dv_alert

After analysis, if you change any of the processing parameters you will need to re-run the analyse step.

Peak / XOffs / YOffs

Once analysis is complete, these display some statistical results.

Aggressiveness

ch-dvo_steady_params_processor_aggressiveness

 

This parameter determines how aggressive the effect should be in attacking unsteadiness.

 

Range :

1 - 10

Default :

5

 

Low values are used for fine errors (small and quick) e.g. introduced by a scanner/telecine and does not try correct for slower and larger movements.

 

High values does not only take care of fine errors but also handles coarse errors (large and slow) like very old material or handheld/shaky cameras.

Reduction

ch-dvo_steady_params_processor_reduction

 

Used to set how much the unsteadiness should be decreased, with separate controls for horizontal (X) and vertical (Y) reduction.

 

Range :

0 - 100

Default :

100 %

 

dv_note

Reduction is typically set to 100% to achieve maximum correction.

 

dv_note

A bit of residual unsteadiness might be necessary to create a more natural result sometimes e.g. a camera shaking during frame capture resulting in motion blur.

Max Adjust

ch-dvo_steady_params_processor_maxadjust

 

Sets a maximum limit (in pixels) for how much the process is allowed to adjust the stabilized frames, with separate horizontal (X) and vertical (Y) controls.

 

Range :

0 - 100

Default :

20 pixels

Motion Safety

ch-dvo_steady_params_processor_motionsafety

 

Adaptively reduces the unsteadiness correction based on motion.

 

Range :

0 - 10

Default :

5

 

In high motion sequences, errors are more likely to occur.  A high Motion Safety setting limits the allowed unsteadiness correction so that any errors will become less obvious.

 

dv_note

A low setting ignores almost all motion.

Quality Safety

ch-dvo_steady_params_processor_qualitysafety

 

Adaptively reduces the unsteadiness correction in accordance with an analyze quality measure recorded during the analyse pass.

 

Range :

0 - 10

Default :

3

 

Under certain circumstances, the analysis may be complex and more difficult. This is  signaled by a quality value.

 

When the analysis quality is low, errors are more likely to occur. In this case a high setting of the Quality Safety control limits the allowed unsteadiness correction in such parts of the material, so that any errors will become less obvious.

 

dv_note

A low setting generally ignores the analysis quality.

Mask

ch-dvo_steady_params_processor_mask

Mode

Determines if and how the (shaking) borders should be masked.

 

Values :

Disable, Follow Max Adjust, Specific

Default :

Follow Max Adjust

 

where :

 

Disable - Less safety. Less accurate.
Follow Max Adjust - Use settings as per Max Adjust parameter
Specific - use settings as per Max Size parameter

Size

Sets the mask size for Specific mode.

 

Range :

0 - 100

Default :

20

Soft Border

When Enabled (default), creates a soft border where the picture has been clipped.

 

dv_note

A soft border can give a more natural look.

Zoom

Enlarges the picture according to selected mode.

 

Values :

Disable, To Blanking, Fill Screen (Letter/Pillar Boxed), Fill SCreen (Full)

Default :

Disable

 

Disable - No zoom - Default
To Blanking - Enlarges to specified blanking (see below)
Fill Screen (Letter/Pillar Boxed) - Enlarges picture until either full vertical or full horizontal size is reached.
Fill Screen (Full) - If necessary, makes a cutout to fill the complete frame (i.e. no black borders/blanking)

 

dv_note

All modes keep the correct aspect ratio

Blanking

ch-dvo_steady_params_processor_blanking

 

The Blanking Mode determines whether to use a masked or a full image.

 

Set blanking mode to Specific and specify Blanking Size if blanking (mattes) should be added to the processed pictures.

 

Disable - Use complete image
Specific - Apply blanking (mattes) according to Blanking Size controls - Default

Border Size

Range :

0 - 2048

Default :

0 pixels

 

This specifies the number of pixels from the each edge of the picture.

Scene Cut

ch-dvo_steady_params_processor_scenecut

 

Determines if the first/last frame of a scene/shot should be adjusted (Low/Medium/High Safety) or not (Fixed). Start and End mode are set separately.

 

dv_note

Under certain circumstances (typically for very unsteady material), a Fixed setting might look wrong.

 

Darrow-up.png     Previous Next