UM:Dvo Effects Dvo Flicker
|From Release :||2014.2|
Older Versions :
DVO Flicker analyses the image sequence to remove brightness and chrominance fluctuations. These may be caused by varying exposure time, unsynchronized light sources, telecine transfer, aging film stock and/or film chemical related issues.
Chrominance fluctuations are often termed chroma breathing.
The tool settings have been split into :
- General - common settings for overall flicker
- Splice - for dedicated issues that can occur at scene cuts
The General page lists common settings for the flicker tool.
The Enable button enables the entire effect :
The main configuration consists of two processing options :
- Global - Analyses and process the whole image.
- Local - Analyses and process invariants of local parts of the picture
Choose the colour mode we use for analysis and processing.
|RGB||Will find flicker in individual RGB colour channels (chroma flicker). DEFAULT|
|Luma||Analyse and process the luminance component only.|
|BW||Black and White. Uses the Green (G) channel to analyse and process. Also sets R,B channels to G.|
|RGB->BW||Convert RGB to Black and White before analysing and processing.|
The BW options are faster since they use one channel only.
Temporal Window defines the number of frames to use for the analysis.
|Values||1 3 5 7 9 11 13 15 ... 29 31|
Variation Control defines how controlled (or careful) we are when we make adjustments.
Higher values are more careful. Lower values allow for larger adjustments.
|Values||0.00 - 1.00|
Lower values (allowing larger adjustments) are best for simple scenes. Larger settings may be required to take better account of more complex and dynamic scenes with more real-world intensity changes (e.g. high-speed pans).
This sets an adjustment limit to the General processing mode. The setting corresponds to absolute value.
|Values||0 - 1023|
Black Level Save lets us enable specific processing to preserve black levels in the sequence.
When Enabled (default), the Low and High parameters are used to assign the level of processing performed at the lower (blackest) end of the input sequence. Both Low and High are 10 bit numbers and limited to values between 0 and 100 (out of the full 10 bit range, 1024).
If the input level is less than or equal to the setting for Low, no flicker adjustment is performed and the input signal is untouched.
|Values||0 - 100|
If the input level is greater than or equal to the setting for High, full flicker adjustment is performed.
|Values||0 - 100|
Between these values, there is a soft transition between none and full processing.
Local enables local adaptive flicker processing.
Aggressiveness defines how much Local mode processing to do.
|Values||1 - 10|
Locality defines the size of the spatial variation of the intensity (i.e. area). A lower value will define a smaller region of intensity to be processed.
|Values||-5 - 5|
Feedback defines a temporal pipeline (i.e. frames) to enhance the process of the Local variation.
In high motion sequences, Feedback may be lowered to decrease influence of other frames in the result.
|Values||0 - 1.00|
The Splice settings manage intensity deviation that might occur at scene changes.
Early optical color timing had a tendency to be inexact (or less responsive). This could cause a darker image at the start of the scene.
Can be enabled for the start and end of a scene independently.
If Enabled the tool will perform a process pass that will force the intensity in the selected range to match its corresponding reference frame.
Frames Start / End set the reference frame and process range.
|Values||0 - 15|
- See the General section above.
If you only need to fix Splice type flicker issues, then :
- Disable General / Local
- Enable General / Global / Max Adjust
- Set General / Global / Max Adjust Limit to 0