Level TOP

From Derivative
Jump to: navigation, search

Summary
[edit]

The Level TOP adjusts image contrast, brightness, gamma, black level, color range, quantization, opacity and more. See also the Luma Level TOP which preserves hue and saturation more accurately, but is slower.

The Level TOP's features have been built into one TOP to maximize performance in a single pass. It takes all its parameters to make a lookup table on the CPU, so animating parameters in the Level TOP will decrease its performance as the lookup table is recreated each frame that a parameter changes.

PythonIcon.pnglevelTOP_Class


Parameters - Pre Page

Clamp Input to [0-1] clampinput -

Invert invert - Inverts the colors in the image. Black becomes white, white becomes black. Colors invert across the color wheel, so red becomes cyan, blue becomes yellow, green becomes magenta, and so on.  

Black Level blacklevel - Any pixel with a value less than or equal to this will be black.  

Brightness 1 brightness1 - Increases or decreases the brightness of an image. Brightness can be considered the arithmetic mean of the RGB channels. The Brightness parameter adds or subtracts an offset into the R, G, and B channels. Low brightness will result in dark tones, while high brightness will wash the color out towards white.  

Gamma 1 gamma1 - The Gamma parameter applies a gamma correction to the image. Gamma is the relationship between the brightness of a pixel as it appears on the screen, and the numerical value of that pixel. This is often represented by a gamma curve. The difference between brightness and gamma is that gamma also affects the ratio of red to green to blue. A straight, linear gamma curve with a value of 1 means no change.  

Contrast contrast - Contrast applies a scale factor (gain) to the RGB channels. Increasing contrast will brighten the light areas and darken the dark areas of the image, making the difference between the light and dark areas of the image stronger.  


Parameters - Range Page

In Low inlow - Any pixel below this value appears black.  

In High inhigh - Any pixel above this value appears white.  

Out Low outlow - Clamps pixel values to this value or higher.  

Out High outhigh - Clamps pixel values to this value or lower.  


Parameters - RGBA Page

Low R lowr - Clamps the minimum level of the red channel.  

High R highr - Clamps the maximum level of the red channel.  

Low G lowg - Clamps the minimum level of the green channel.  

High G highg - Clamps the maximum level of the green channel.  

Low B lowb - Clamps the minimum level of the blue channel.  

High B highb - Clamps the maximum level of the blue channel.  

Low A lowa - Clamps the minimum level of the alpha channel.  

High A higha - Clamps the maximum level of the alpha channel.  


Parameters - Step Page

Apply Stepping stepping -

Step Size stepsize - Posterizes the image into bands or stripes. Number of bands equal to the inverse of this parameter (i.e., 0.25 = 4 bands). Use a default Ramp TOP to easily see this parameter's effect.  

Threshold threshold - Offsets the position of the step boundaries.  

Clamp Low clamplow - Clamps the image's minimum value. (value as in hue, saturation, and value)  

Clamp High clamphigh - Clamps the image's maximum value. (value as in hue, saturation, and value)  

Soften soften - Softens or blends the boundaries between steps.  


Parameters - Post Page

Gamma 2 gamma2 - A second gamma correction that is added after the Range, RGBA, and Step page adjustments have been applied.  

Opacity opacity - Adjust the opacity, or transparency, of the image.  

Brightness 2 brightness2 - A second brightness adjustment that is added after the Range, RGBA, and Step page adjustments have been applied.  

Clamp clamp - Clamps pixel values to this value or lower.

Clamp Low clamplow2 - Clamps the image's minimum value. (value as in hue, saturation, and value)  

Clamp High clamphigh2 - Clamps the image's maximum value. (value as in hue, saturation, and value)  


Parameters - Common Page

Output Resolution outputresolution - - quickly change the resolution of the TOP's data.

  • Use Input useinput - Uses the input's resolution.
  • Eighth eighth - Multiply the input's resolution by that amount.
  • Quarter quarter - Multiply the input's resolution by that amount.
  • Half half - Multiply the input's resolution by that amount.
  • 2X 2x - Multiply the input's resolution by that amount.
  • 4X 4x - Multiply the input's resolution by that amount.
  • 8X 8x - Multiply the input's resolution by that amount.
  • Fit Resolution fit - Multiply the input's resolution by that amount.
  • Limit Resolution limit - Multiply the input's resolution by that amount.
  • Custom Resolution custom - Enables the Resolution parameter below, giving direct control over width and height.

Resolution resolution - Enabled only when the Resolution parameter is set to Custom Resolution. Some Generators like Constant and Ramp do not use inputs and only use this field to determine their size. The drop down menu on the right provides some commonly used resolutions.

Resolution Menu resmenu -

Use Global Res Multiplier resmult - Uses the Global Resolution Multiplier found in Edit>Preferences>TOPs. This multiplies all the TOPs resolutions by the set amount. This is handy when working on computers with different hardware specifications. If a project is designed on a desktop workstation with lots of graphics memory, a user on a laptop with only 64MB VRAM can set the Global Resolution Multiplier to a value of half or quarter so it runs at an acceptable speed. By checking this checkbox on, this TOP is affected by the global multiplier.

Output Aspect outputaspect - - Sets the image aspect ratio allowing any textures to be viewed in any size. Watch for unexpected results when compositing TOPs with different aspect ratios. (You can define images with non-square pixels using xres, yres, aspectx, aspecty where xres/yres != aspectx/aspecty.)

  • Use Input useinput - Uses the input's aspect ratio.
  • Resolution resolution - Uses the aspect of the image's defined resolution (ie 512x256 would be 2:1), whereby each pixel is square.
  • Custom Aspect custom - Lets you explicitly define a custom aspect ratio in the Aspect parameter below.

Aspect aspect- - Use when Output Aspect parameter is set to Custom Aspect.

Aspect1 aspect1 -


Aspect2 aspect2 -

Aspect Menu armenu -

Input Smoothness inputfiltertype - - This controls pixel filtering on the input image of the TOP.

  • Nearest Pixel nearest - Uses nearest pixel or accurate image representation. Images will look jaggy when viewing at any zoom level other than Native Resolution.
  • Interpolate Pixels linear - Uses linear filtering between pixels. This is how you get TOP images in viewers to look good at various zoom levels, especially useful when using any Fill Viewer setting other than Native Resolution.
  • Mipmap Pixels mipmap - Uses mipmap filtering when scaling images. This can be used to reduce artifacts and sparkling in moving/scaling images that have lots of detail.

Fill Viewer fillmode - - Determine how the TOP image is displayed in the viewer. NOTE:To get an understanding of how TOPs work with images, you will want to set this to Native Resolution as you lay down TOPs when starting out. This will let you see what is actually happening without any automatic viewer resizing.

  • Use Input useinput - Uses the same Fill Viewer settings as it's input.
  • Fill fill - Stretches the image to fit the edges of the viewer.
  • Fit Horizontal width - Stretches image to fit viewer horizontally.
  • Fit Vertical height - Stretches image to fit viewer vertically.
  • Fit Best best - Stretches or squashes image so no part of image is cropped.
  • Fit Outside outside - Stretches or squashes image so image fills viewer while constraining it's proportions. This often leads to part of image getting cropped by viewer.
  • Native Resolution nativeres - Displays the native resolution of the image in the viewer.

Viewer Smoothness filtertype - - This controls pixel filtering in the viewers.

  • Nearest Pixel nearest - Uses nearest pixel or accurate image representation. Images will look jaggy when viewing at any zoom level other than Native Resolution.
  • Interpolate Pixels linear - Uses linear filtering between pixels. Use this to get TOP images in viewers to look good at various zoom levels, especially useful when using any Fill Viewer setting other than Native Resolution.
  • Mipmap Pixels mipmap - Uses mipmap filtering when scaling images. This can be used to reduce artifacts and sparkling in moving/scaling images that have lots of detail.

Passes npasses - Duplicates the operation of the TOP the specified number of times. Making this larger than 1 is essentially the same as taking the output from each pass, and passing it into the first input of the node and repeating the process. Other inputs and parameters remain the same for each pass.

Channel Mask chanmask - Allows you to choose which channels (R, G, B, or A) the TOP will operate on. All channels are selected by default.

Pixel Format format - - Format used to store data for each channel in the image (ie. R, G, B, and A). Refer to Pixel Formats for more information.

  • Use Input useinput - Uses the input's pixel format.
  • 8-bit fixed (RGBA) rgba8fixed - Uses 8-bit integer values for each channel.
  • sRGB 8-bit fixed (RGBA) srgba8fixed - Uses 8-bit integer values for each channel and stores color in sRGB colorspace.
  • 16-bit float (RGBA) rgba16float - Uses 16-bits per color channel, 64-bits per pixel.
  • 32-bit float (RGBA) rgba32float - Uses 32-bits per color channel, 128-bits per pixels.
  • 10-bit RGB, 2-bit Alpha, fixed (RGBA) rgb10a2fixed - Uses 10-bits per color channel and 2-bits for alpha, 32-bits total per pixel.
  • 16-bit fixed (RGBA) rgba16fixed - Uses 16-bits per color channel, 64-bits total per pixel.
  • 11-bit float (RGB), Positive Values Only rgba11float - A RGB floating point format that has 11 bits for the Red and Green channels, and 10-bits for the Blue Channel, 32-bits total per pixel (therefore the same memory usage as 8-bit RGBA). The Alpha channel in this format will always be 1. Values can go above one, but can't be negative. ie. the range is [0, infinite).
  • 16-bit float (RGB) rgb16float -
  • 32-bit float (RGB) rgb32float -
  • 8-bit fixed (Mono) mono8fixed - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 8-bits per pixel.
  • 16-bit fixed (Mono) mono16fixed - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 16-bits per pixel.
  • 16-bit float (Mono) mono16float - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 16-bits per pixel.
  • 32-bit float (Mono) mono32float - Single channel, where RGB will all have the same value, and Alpha will be 1.0. 32-bits per pixel.
  • 8-bit fixed (RG) rg8fixed - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 8-bits per channel, 16-bits total per pixel.
  • 16-bit fixed (RG) rg16fixed - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 16-bits per channel, 32-bits total per pixel.
  • 16-bit float (RG) rg16float - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 16-bits per channel, 32-bits total per pixel.
  • 32-bit float (RG) rg32float - A 2 channel format, R and G have values, while B is 0 always and Alpha is 1.0. 32-bits per channel, 64-bits total per pixel.
  • 8-bit fixed (A) a8fixed - An Alpha only format that has 8-bits per channel, 8-bits per pixel.
  • 16-bit fixed (A) a16fixed - An Alpha only format that has 16-bits per channel, 16-bits per pixel.
  • 16-bit float (A) a16float - An Alpha only format that has 16-bits per channel, 16-bits per pixel.
  • 32-bit float (A) a32float - An Alpha only format that has 32-bits per channel, 32-bits per pixel.
  • 8-bit fixed (Mono+Alpha) monoalpha8fixed - A 2 channel format, one value for RGB and one value for Alpha. 8-bits per channel, 16-bits per pixel.
  • 16-bit fixed (Mono+Alpha) monoalpha16fixed - A 2 channel format, one value for RGB and one value for Alpha. 16-bits per channel, 32-bits per pixel.
  • 16-bit float (Mono+Alpha) monoalpha16float - A 2 channel format, one value for RGB and one value for Alpha. 16-bits per channel, 32-bits per pixel.
  • 32-bit float (Mono+Alpha) monoalpha32float - A 2 channel format, one value for RGB and one value for Alpha. 32-bits per channel, 64-bits per pixel.


TOPs
Analyze • Anti Alias • Blob Track • Blur • Cache Select • Cache • Channel Mix • CHOP to • Chroma Key • Circle • Composite • Constant • Convolve • Corner Pin • CPlusPlus • Crop • Cross • Cube Map • Depth • Difference • DirectX In • DirectX Out • Displace • Edge • Emboss • Feedback • Fit • Flip • GLSL Multi • GLSL • HSV Adjust • HSV to RGB • In • Inside • Introduction To TOPs id• Kinect • Layout • Leap Motion • Level • Lookup • Luma Blur • Luma Level • Math • Matte • Monochrome • Movie File In • Movie File Out • Experimental:Movie File Out • Multiply • NDI In • Noise • Normal Map • Null • Oculus Rift • OP Viewer • OpenColorIO • OpenVR • Out • Outside • Over • Pack • Photoshop In • PreFilter Map • Projection • Ramp • RealSense • Rectangle • Remap • Render Pass • Render Select • Render • Reorder • Resolution • RGB Key • RGB to HSV • Scalable Display • Screen Grab • Screen • Select • Shared Mem In • Shared Mem Out • Slope • SSAO • Substance Select • Substance • Subtract • SVG • Switch • Syphon Spout In • Text • Texture 3D • Texture iltering• Texture Sampling arameters• Threshold • Tile • Time Machine • TOP• TOP iewer• Touch In • Touch Out • Transform • Under • Video Device In • Video Device Out • Video Stream In • Video Stream Out • Vioso • Web Render • ZED

An that creates, composites and modifies images, and reads/writes images and movies to/from files and the network. TOPs run on the graphics card's GPU.

The width and height of an image in pixels. Most TOPs, like the can set the image resolution. See for the width/height ratio of an image, taking into account non-square pixels.

The viewer of a node can be (1) the interior of a node (the ), (2) a floating window (RMB->View... on node), or (3) a that graphically shows the results of an operator.

A outputs one or more channels, where a channel is simply a sequence of numbers, representing motion, audio, etc. Channels are passed between CHOPs in TouchDesigner networks. See also .