Image Editor

The nXt Image Editor can edit native image files (.nXtImage) produced by any of the nXt platforms. These native files retain all of the information gathered during rendering. By using the nXt Image Editor, you can:

• Adjust the tone operator settings.
• Change the intensity of any lighting channel.
• Add special image-based effects: Haze, Depth Blur, and Glare.
• Save a tone-mapped image in a bitmap format such as .jpg or .png.
• Save the luminance information to an HDR format.
• View and save additional masked channels ( alpha, distance, material ) for use in advanced compositing.
• Save a Piranesi© file format (*.epx) which can be used to create non photorealistic rendering.
• Use Image Arithmetic for tasks such as stitching together an image that has been generated by separate nodes on the render farm.
• Save the Lighting Settings used to generate this rendering. These Lighting Settings can then be used to generate more renderings.

To launch the editor

On the Flamingo nXt 5.0 menu, click More Tools > Flamingo nXt Image Editor.

File menu

Open

Opens a file saved in nXtImage format for editing.

Save Source Image

Saves the nXtImage file.

Save Source Image As

Saves the nXtImage file under a different name.

Save Tonemapped Image As

Saves the edited image as a bitmap image file.

• JPEG (.jpg)
• TIFF (.tif)
• TIFF with Alpha Channel (.tif)
• PNG (.png)
• PNG with Alpha Channel (.png)
• Piranesi EPix file (.epx)

Piranesi is a 3-D painting tool that creates images with a hand-painted appearance.

Save HDR Image As

• HDR File (.hdr)
• EXR File (.exr)
• EXR with Alpha Channel (.exr)

Save Mask

nXtImage files contain three additional channels that can be used as masks for advanced compositing in most bitmap editors. These channels carry alpha, distance, and material information for each pixel, encoded in a gray-scale image. Each channel can be viewed and saved to a .png file.

Notes:

1. The alpha channel can be included with a tone-mapped image by selecting a file format with Alpha when saving a tone-mapped image.
2. Distance and Materials channels are not antialiased and may show some hard-edged artifacts. Adding a small amount of Gaussian blur to a mask before using it may help soften these edges.
3. The Materials channel will only uniquely encode 255 different materials. If your model contains more materials than that, some mask colors will repeat.

Materials Channel

Saves the material channel mask.

Alpha Channel

Saves the alpha channel mask.

Distance Channel

Saves the distance channel mask.

Save Lighting Settings As

Saves the lighting scheme.

Image menu

Info

Displays information about the image.

Arithmetic

Allows piecing together or overlaying segments of images rendered using the Render Farm Single Image function.

To piece image segments:

1. On the File menu, click Open.
2. Select the first image of the sequence, for example, 000000.nXtImage.
3. On the Image menu, click Arithmetic, and then click Add.
4. Select all of the other images in the sequence.

Note: Do not select the first image (000000.nXtImage) again or it will be added twice.

Add

Adds pixel values of one layer to the other. When values are above 255 (in the case of RGB), white is displayed.

Subtract

Subtracts pixel values of one layer from the other. When values are negative, black is displayed.

Difference

Subtracts the top layer from the bottom layer or the other way round, to always get a positive value. Blending with black produces no change, as values for all colors are 0. Blending with white inverts the picture.

Masked Add

Takes the transparent alpha-channel mask into account when blending.

Combine Path Tracings

Combines images rendered using the Path Tracer engine so that, for example, when you combine ten images rendered with 20 passes each becomes the equivalent of an image rendered with 200 passes.

Rendered with 20 passes (left), ten 20-pass images combined to create a 200-pass image (right).

Apply Patch

Inserts an image rendered as a selected portion into the rendered image.

Animation

You can animate by changing the image information.

To animate image effects

1. Set up the first image. Click the Plus (+) button next to the Frame edit box.
2. Edit the image and add frames.
3. Click Image > Animation, and in the dialog box, click Preview.
4. If all is well, click Animate.

Create a folder.

A sequence of images will be created that can be used to create an animation using software designed for this purpose.

View menu

Specifies what to display in the image.

Image

Displays the original rendered image.

Image and Alpha Mask

Displays the image and the alpha channel mask together.

Material Mask

Displays the material mask.

Distance Mask

Displays the distance mask.

Using the image editor

Load an Image

1. Save your rendering results as an .nXtImage.
2. On the Flamingo nXt menu, click Utilities > Flamingo nXt Image Editor.
3. In the nXt Image Editor, on the File menu, click Open to load the image into the editor.

Tone mapping

Tone mapping is the process of converting the luminance data used by nXt into RGB pixels that can be displayed or printed.

Brightness

See Render Window: Brightness. Note: In nXt, the overall brightness of a scene cannot be controlled by boosting the intensity of the light sources. The automatic exposure adjustment built into the tone-mapping process will defeat this. Adjust overall scene brightness by using the Brightness control.

Burn

See Render Window: Burn.

Saturation

See Render Window: Saturation.

Histogram

See Render Window: Histogram.

Status Fields

The status fields are located at the bottom of the screen. As you move your cursor over the image, these fields display information about each pixel.

Pixel

The pixel coordinate, measured from the lower left corner.

Color

The first three fields display the RGB colors displayed in the image after tonemapping. The fourth field shows the alpha (transparency) channel, which is used for compositing.

Value

The luminance value for each of the red, green, and blue sub-channels.

Lum

A weighted average of the luminance values stored in each pixel.

Depth

The distance of each pixel from the viewer in meters. Negative values indicate a background pixel.

Material

The name of the material used to render the pixel.

FX Settings

Special Effects can be added to an image. Many of these effects use the extra information the NXTimage format stores. For instance the glare uses luminance space working on actual light values and the haze uses distance in the image.

Haze

Adds color to pixels farther from the camera. This effect can be used to add a haze or fog effect to a scene or to mask a background with color or change the background color.

Original image (left) and with haze (right).

Strength

Specifies the intensity of the haze color.

Near

The distance from the camera where haze will start adding color to each pixel.

Pick

Pick a point on the image to specify the distance.

Far

The distance where the haze effect is at its maximum. All pixels beyond this point have the maximum haze effect added to each pixel. Pixels between near and far have haze added in a linear fashion from the near to the far pixels.

Pick

Pick a point on the image to specify the distance.

Color

The haze color.

Pick

Pick a point on the image to specify the color.

Depth Blur

Since each pixel in the image contains a distance value, this can be used to blur the image between specified distances.

Original image (left) and with depth blur (right).

Strength

Specifies the amount of blur.

Focus

Specifies a distance in the image that will be in focus.

Pick

Pick a point on the image to specify the focus distance.

In-Focus Zone

The distance around the Focus that is sharp. This value is in meters. All pixels within this distance will be sharp and will be ignored by the Blur filter. Pixels beyond this distance will be progressively blurred with neighboring pixels to give the illusion of depth of field.

Blur

Controls which direction the blur filter will work. The default value is Background. This means all pixels farther away from the camera than the In-Focus Zone will progressively blur.

Blur foreground (left) and background (right).

Background

Blurs pixels farther away from the camera than the In-Focus Zone range.

Foreground

Blurs pixels that are closer to the camera than the In-Focus Zone range.

Both

Blur pixels both in front and behind the In-Focus Zone range. This is a quick way to get a depth-of-field effect. It is not as accurate as using the built-in pre-render Depth of field.

Glare

Glare affects pixels that are brighter than the Threshold in lumens by creating a halo effect on the surrounding pixels. Only the brightest pixels in the image are affected. Hold the cursor over the pixels to see glare and read the total lumens of that pixel.

Original image (left) and with glare (right).

Strength

Adjusts the amount of halo that affects the surrounding pixels.

Threshold

The lower limit of the value affected by the glare filter. All pixels brighter than this value will be affected.

Pick

Pick a point on the image to specify the brightness value.

Vignette

Blurs and blends the colors on the edges of the image to create a halo effect.

Original image (left) and with vignette (right).