Deathray
From Avisynth wiki
| Abstract | |
|---|---|
| Author | Jawed |
| Version | v1.04 |
| Download | [x86]: Deathray.dll
[x64]: Deathray.dll |
| Category | Spatial-Temporal Denoisers |
| License | BSD |
| Discussion | Doom9 Thread |
Contents |
Description
Deathray is an OpenCL GPU accelerated spatial/temporal non-local means de-noising filter.
Requirements
- [x86]: AviSynth+ or AviSynth 2.6
- [x64]: AviSynth+
- Supported color formats: YV12
The following software configurations are known to work:
- AMD Stream SDK 2.3 and AMD APP SDK 2.8.1
- AMD Catalyst 10.12 and 13.8 beta 2
- Windows Vista 64-bit and Windows 8 64-bit
- NVidia software is known to work but drivers unknown
The following hardware configurations are known to work:
- ATI HD 5870
- AMD HD 7770
- AMD HD 7970
- Various NVidia, models unknown
Known non-working hardware:
- ATI cards in the 4000 series or earlier
- ATI cards in the 5400 series
Syntax and Parameters
Syntax
=====
deathray (clip, float "hY, float "hUV", int "tY", int "tUV", float "s", int "x", bool "l", bool "c", bool "z", bool "b")
Usage
=====
Deathray separates the video into its 3 component planes and processes each
of them independently. This means some parameters come in two flavours: luma
and chroma.
Filtering can be adjusted with the following parameters, with the default
value for each in brackets:
hY (1.0) - strength of de-noising in the luma plane.
Cannot be negative.
If set to 0 Deathray will not process the luma plane.
hUV (1.0) - strength of de-noising in the chroma planes.
Cannot be negative.
If set to 0 Deathray will not process the chroma planes.
tY (0) - temporal radius for the luma plane.
Limited to the range 0 to 64.
When set to 0 spatial filtering is performed on the
luma plane. When set to 1 filtering uses the prior,
current and next frames for the non-local sampling
and weighting process. Higher values will increase
the range of prior and next frames that are included.
tUV (0) - temporal radius for the chroma planes.
Limited to the range 0 to 64.
When set to 0 spatial filtering is performed on the
chroma planes. When set to 1 filtering uses the prior,
current and next frames for the non-local sampling
and weighting process. Higher values will increase
the range of prior and next frames that are included.
s (1.0) - sigma used to generate the gaussian weights.
Limited to values of at least 0.1.
The kernel implemented by Deathray uses 7x7-pixel
windows centred upon the pixel being filtered.
For a 2-dimensional gaussian kernel sigma should be
approximately 1/3 of the radius of the kernel, or less,
to retain its gaussian nature.
Since a 7x7 window has a radius of 3, values of sigma
greater than 1.0 will tend to bias the kernel towards
a box-weighting. i.e. all pixels in the window will
tend towards being equally weighted. This will tend to
reduce the selectivity of the weighting process and
result in relatively stronger spatial blurring.
x (1) - factor to expand sampling.
Limited to values in the range 1 to 14.
By default Deathray spatially samples 49 windows
centred upon the pixel being filtered, in a 7x7
arrangement. x increases the sampling range in
multiples of the kernel radius.
Since the kernel radius is 3, setting x to 2 produces
a sampling area of 13x13, i.e. 169 windows centred
upon the target pixel. Yet higher values of x such as
3 or 4 will result in 19x19 or 25x25 sample windows.
Deathray uses 32x32 tiles to accelerate its processing.
Each tile is equipped with a border of 8 pixels around
all four edges, with pixels copied from neighbouring
tiles, or mirrored from within the tile if the tile
edge corresponds with a frame edge. This apron of 8
extra pixels ensures that the default sampling of
49 windows is correct, allowing pixels near the edge of
the tile to employ 49 sample windows that all have
valid pixels.
When x is set to 2 or more, sampling will "bump" into
the edges defined by the 48x48 region. With strong
values of the de-noising parameters this will create
artefacts in the filtered image. These artefacts are
visible as a grid of vertical and horizontal lines
corresponding with the 32x32 arrangement of the tiles.
l (false) - linear processing of luma plane.
true or false.
This option allows processing in linear space instead
of the default gamma space.
c (true) - correction after filtering.
true or false.
This option applies a correction after filtering
to limit the amount of filtering per pixel.
When set to false the naked NLM algorithm is used.
z (false) - target pixel tends towards zero-weighted.
true or false.
Reduces the weight of the pixel being filtered to
a minimum. This results in more even filtering across
the tonal range from shadows to highlights.
The standard NLM algorithm gives the pixel being filtered
the maximum weight of all. A refinment of the algorithm
is to give the pixel being filtered the maximum weight
derived from all the other pixels that were inspected.
This maximum of other pixels' weights is used when z is
set to false.
When set to true, the minimum of other pixels' weights is
used instead.
b (false) - balanced weighting.
true or false.
Attempts to balance weighting of pixels based upon their
luma value.
This parameter is not applied to chroma planes.
Avisynth MT
Deathray is not thread safe. This means that only a single instance of Deathray can be used per Avisynth script. By extension this means that it is not compatible with any of the multi-threading modes of the Multi Threaded variant of Avisynth.
Use:
SetMTMode(5)
before a call to Deathray in the Avisynth script, if multi-threading is active in other parts of the script.
Multiple Scripts Using Deathray
The graphics driver is thread safe. This means it is possible to have an arbitrary number of Avisynth scripts calling Deathray running on a system.
e.g. 2 scripts could be encoding, another could be running in a media player and another could be previewing individual frames in AvsP or VirtualDub.
Eventually video memory will probably run out, even though it's virtualised.
System Responsiveness
Currently graphics drivers are unable to confer user-responsiveness
guarantees on OpenCL applications that utilise GPUs. This means if you
are using Deathray on a frame size of 16 million pixels, there will be some
juddering in Windows every ~0.7 seconds (1.5 frames per second on HD 5870)
accompanied by difficulty in typing, etc.
Examples
deathray with all default settings:
AviSource("Blah.avi") deathray ()
Changelog
1.04 - Marks use of OpenCL 1.1 features, that have been deprecated in 1.2, as preferred.
This keeps AMD SDK from complaining.
1.03 - Fixed black pixels bug with low values of hY and z=true (also affected chroma with low values of hUV)
Fixed bug with allocation of a spurious buffer
1.02 - Added new l, c, z and b options
Temporal filtering now re-weights target pixel based upon all sampled frames
1.01 - Removed logging to stderr (was only present in NVidia debug version);
Includes post-filtering correction first introduced in NVidia debug version;
Updated to use AMD APP SDK;
Updated to VS2012 Express Edition;
Updated DLL so that it is not dependent upon visual C runtime - see post 70;
1.00 - Initial version
External Links
- GitHub - Source code repository.
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