Image Enhancement Parameters
Viesus uses a JSON-style configuration file to control image enhancement parameters. This document describes all available parameters organized by configuration sections.
Global Parameters
Global parameters control enhancement algorithms applied to the entire image. They are located in the GPars section of the configuration file.
Enhancement Strength Parameters
VIESUS automatically calculates an individual correction for each image. The following parameters influence how strong the correction is applied. The parameters can be interpreted to apply more or less application of the calculated correction.
| Parameter | Range | Default | Description |
|---|---|---|---|
brstrength | 0.0 to 1.0 | 0.5 | Brightness correction (most visible on underexposed images) |
ccstrength | 0.0 to 1.0 | 0.5 | Color correction (removes color casts) |
shplocalstrength | 0.0 to 1.0 | 0.5 | Local sharpening strength (visible in foliage, less in sky regions) |
nrmonostrength | 0.0 to 1.0 | 0.5 | Noise reduction strength for monochrome images |
nrstrength | 0.0 to 1.0 | 0.5 | Noise reduction strength for color images |
gastrength | 0.0 to 1.0 | 0.5 | Grain addition strength (reduces banding/posterization) |
Specialized Enhancement Parameters
| Parameter | Range | Default | Description |
|---|---|---|---|
rerstrength | 0.0 to 1.0 | 1.0 | Red-eye reduction (higher values increase detection but also false positives) |
fdstrength | 0.0 to 4.0 | 0.5 | Face detection influences the sizes of detected faces. Higher values look for smaller faces at the cost of execution time. Higher values may be needed for group shots with many smaller faces. |
eyestrength | 0.0 to 1.0 | 0.5 | Eye detection strictness for red-eye correction |
frstrength | 0.0 to 1.0 | 0.3 | Face reconstruction strength for smaller faces |
blurstrength | 0.0 to 1.0 | 0.0 | Background blur/computational bokeh strength |
srstrength | 0.0 to 1.0 | 0.9 | Super resolution blending strength with default upscaling |
sfstrength | 0.0 to 1.0 | 0.25 | Small face reconstruction importance (0.25-0.50 recommended) |
dastrength | 0.0 to 1.0 | 0.5 | Dark scene/night shot brightness correction strength |
Manual Correction Parameters
Manual corrections are static and are applied in disregard of the results of the image analysis at the end of the automatic processing of the images. Changes to these parameters should be done carefully.
| Parameter | Range | Default | Description |
|---|---|---|---|
brightness | -1.0 to 1.0 | 0.0 | Global brightness adjustment |
contrast | -1.0 to 1.0 | 0.0 | Global contrast adjustment |
saturation | -1.0 to 1.0 | 0.0 | Global saturation adjustment |
b | -1.0 to 1.0 | 0.0 | Blue channel color balance adjustment |
g | -1.0 to 1.0 | 0.0 | Green channel color balance adjustment |
r | -1.0 to 1.0 | 0.0 | Red channel color balance adjustment |
shpglobalstrength | 0.0 to 1.0 | 0.0 | Global sharpening strength |
Local Parameters
Local parameters control corrections applied to specific image regions and are located in the LPars section of the configuration file.
| Parameter | Range | Default | Description |
|---|---|---|---|
highlightfac | 0.0 to 1.0 | 0.5 | Highlight region correction factor |
shadowfac | 0.0 to 1.0 | 0.5 | Shadow region correction factor |
colorfac | 0.0 to 1.0 | 0.5 | Color-specific region correction factor |
skintoneadjfac | 0.0 to 1.0 | 0.2 | Saturation reduction in face regions (prevents "glowing" faces) |
addflashfac | 0.0 to 1.0 | 0.5 | Adaptive shadow highlighting for faces (0.3 recommended) |
Color-Specific Adjustments
The parameters influence specific color regions that are considered important for image quality. For each of the color regions skin, sky and vegetation individual adjustments are supported. They are located in the subsections Lpars.skin, Lpars.sky and Lpars.veg.
Local Color Correction Parameters
| Parameter | Range | Default | Description |
|---|---|---|---|
huerotation | -10 to 10 | 0.0 | Hue rotation for the specific color region |
saturation | -1.0 to 1.0 | 0.0 | Saturation adjustment for the specific color region |
brightness | -1.0 to 1.0 | 0.0 | Brightness adjustment for the specific color region |
contrast | -1.0 to 1.0 | 0.0 | Contrast adjustment for the specific color region |
strength | 0.0 to 1.0 | 1.0 | Overall strength of adjustments for the specific color region |
Configuration Parameters
[Config] Section
Controls which processing stages are enabled in the enhancement pipeline.
| Parameter | Values | Default | Description |
|---|---|---|---|
ARmode | 0 .. 2 | 1 | Artifact removal: 0=disabled, 1=Automatic, 2=Always |
Enhancemode | 0 .. 3 | 1 | Enhancement mode: 0=none, 1=normal, 2=no enhance/no manual CC, 3=normal/no manual CC |
RERmode | 0, 1 | 0 | Red-eye reduction: 0=disabled, 1=safe mode |
FDmode | 0 .. 3 | 1 | Face detection: 0=off, 1=normal, 2=full analysis, 3=blur faces |
SHPmode | 0, 1 | 1 | Local sharpening: 0=disabled, 1=enabled |
NoiseRedMode | 0 .. 2 | 0 | Noise reduction: 0=off, 1=auto profiling, 2=AI model |
SKIPmode | 0, 1 | 1 | Skip artificial images: 0=skip, 1=enhance all |
WFmode | 0, 1 | 0 | White fix mode: 0=disabled, 1=enabled |
FRmode | 0 .. 3 | 1 | Face reconstruction: 0=off, 1=default, 2=mixed, 3=fast |
AFFmode | 0, 1 | 0 | Adaptive face flash: 0=disabled, 1=enabled |
ProcessingSequence | 0 .. 3 | 0 | Processing order: 0=default, 1=resize after, 2=resize before, 3=red-eye first |
GAmode | 0, 1 | 0 | Grain addition: 0=disabled, 1=enabled |
BGmode | 0 .. 3 | 0 | Background handling: 0=off, 1=alpha, 2=color replace, 3=image replace |
BGBlurmode | 0, 1 | 0 | Background blurring: 0=disabled, 1=enabled |
BGBalmode | 0 .. 3 | 0 | Background balancing: 0=off, 1=to first, 2=strict, 3=to parameters |
Background Handling
[Background] Section
Configures background replacement and manipulation features.
| Parameter | Type | Default | Description |
|---|---|---|---|
ReplacePath | String | - | Path to replacement background image |
backgroundR | 0-255 | 255 | Red component for background color replacement |
backgroundG | 0-255 | 255 | Green component for background color replacement |
backgroundB | 0-255 | 255 | Blue component for background color replacement |
balanceH | -1.0 to 1.0 | 0.0 | Hue balance adjustment for background |
balanceS | -1.0 to 1.0 | 0.0 | Saturation balance adjustment for background |
balanceV | -1.0 to 1.0 | 0.0 | Value balance adjustment for background |
Resizing Configuration
[Resize] Section
Controls image resizing and super-resolution parameters.
| Parameter | Type | Default | Description |
|---|---|---|---|
ResizeOn | 0, 1 | 1 | Enable/disable resizing |
ResizeFacDetMode | 0, 1, 2, 3 | 1 | Size calculation mode: 0=factor, 1=small side, 2=width, 3=height |
ResizePixSize | Integer | 6000 | Target pixel size (depends on ResizeFacDetMode) |
ResizeFactor | Float | 4.0 | Resize factor (depends on ResizeFacDetMode) |
ResizeMode | 0-9 | 5 | Resize algorithm (see table below) |
SupResThresh | Float | 2.0 | Super-resolution threshold factor |
SRNoiseInjection | 0, 1 | 0 | Inject noise before super-resolution |
Resize Mode Values
| Value | Method | Description |
|---|---|---|
| 0 | Default | Standard default resizing |
| 1 | Bicubic | Bicubic interpolation |
| 2 | Biquadratic | Biquadratic interpolation |
| 3 | Bilinear | Bilinear interpolation |
| 4 | Nearest Neighbor | Nearest neighbor interpolation |
| 5 | Super Resolution 4x | AI-based 4x super-resolution |
| 6 | Default No Super Resolution | Default without super-resolution |
| 7 | Super Resolution 2x/4x | AI-based 2x and 4x super-resolution |
| 8 | Super Resolution 2x/4x Fast | Fast AI-based 2x and 4x super-resolution |
| 9 | Super Resolution 4x Fast | Fast AI-based 4x super-resolution |
Color Management
[ICCProfiles] Section
Controls ICC color profile handling.
| Parameter | Type | Default | Description |
|---|---|---|---|
OutputProfileMode | 0 .. 2 | 0 | Profile mode: 0=sRGB, 1=same as input, 2=custom profile |
OutputProfilePath | String | - | Path to custom ICC profile (when mode=2) |
Other Settings
[Other] Section
Miscellaneous output and processing options.
| Parameter | Type | Default | Description |
|---|---|---|---|
WriteResultFiles | 0, 1 | 0 | Create Excel result files |
JpegComprQuality | 1-100 | 95 | JPEG compression quality |
DPIResolutionSaveDefault | Float | 72.0 | Default DPI value |
DPIResolutionSaveMode | 0-5 | 2 | DPI handling mode (see table below) |
ForceToMonochrome | 0, 1 | 0 | Force monochrome output |
MonochromeToneR | 0.0 to 1.0 | 0.0 | Red tone for monochrome/sepia effects |
MonochromeToneG | 0.0 to 1.0 | 0.0 | Green tone for monochrome/sepia effects |
MonochromeToneB | 0.0 to 1.0 | 0.0 | Blue tone for monochrome/sepia effects |
ManualShadowFac | 0.0 to 1.0 | 0.0 | Manual shadow factor override |
DPI Resolution Save Modes
For image formats that allow saving the actual output resolution used to interpret the image pixel dimensions, the following parameter values influence how VIESUS handles it.
| Mode | Description |
|---|---|
| 0 | Save always and keep DPI value on resize |
| 1 | Save only if available and keep DPI on resize |
| 2 | Save default value to all images |
| 3 | Never save DPI information |
| 4 | Save always - keep image size on resize in cm/inch |
| 5 | Save only if available - keep image size on resize in cm/inch |
Portrait Auto Cropping
[AutoCrop] Section
Controls automatic cropping based on facial detection.
| Parameter | Type | Default | Description |
|---|---|---|---|
HeadYawCoeff | Float | 0.666667 | Coefficient for head yaw adjustment |
HeadPitchCoeff | Float | 0.750000 | Coefficient for head pitch adjustment |
HeadroomFixed | 0, 1 | 1 | Use fixed headroom calculation |
HeadroomUnit | Integer | 0 | Headroom unit type |
ImageToHeadRatio | Float | 0.481635 | Ratio of image to head size |
HeadroomLeft | Float | 0.106061 | Left side headroom |
Headroom | Float | 0.106061 | General headroom |
CropModeHeadroom | Float | 0.000000 | Headroom for crop mode |
AspectHeight | Float | 1.000000 | Target aspect ratio height |
AspectWidth | Float | 1.000000 | Target aspect ratio width |
CropModePortrait | Integer | 2 | Portrait cropping mode |
AdaptAspectRatioToFace | 0, 1 | 1 | Adapt aspect ratio based on face detection |
AspectRatio | Integer | 0 | Fixed aspect ratio mode |
CropMode | Integer | 0 | General cropping mode |
Usage Notes
- Default values of
0.5for strength parameters provide a balanced starting point for most automatic applications - Face-related features should be used with caution in automated workflows
- Background manipulation modes require manual result verification
- Super-resolution modes significantly increase processing time but improve quality for upscaling scenarios