Green Screen Editor

The PLIC Experience Green Screen Editor is used to do green screen extractions on images where the subject is wearing green.

Drew Starr avatar
Written by Drew Starr
Updated over a week ago

Editor Interface

This section explains each part of the Green Screen Editor interface.

A - Tools

  • These are the three tools used to edit the images (Lasso, Brush, and Wand).

B - Tool Settings

  • Each tool has its own settings which are displayed here when the tool is selected in the Tools Panel.

C - Layers

  • The top left image is the source image. This is the original image uploaded to PLIC Experience. By default, selections made with the Wand will come from this layer, hence the red box around the layer.

  • To the right of the source image is the source mask created by ChromaStar®, which is an estimate of where green should be retained on the image. This is where edits are applied to either recover or hide green on the source image. The source mask only affects green pixels. Green which needs to be retained or recovered needs to be white on the mask and green which needs to be hidden needs to be black on the mask. Areas where opacity is used will show as grey on the mask. The backslash key (\) can be pressed to view the source mask in a white overlay view mode. The forward slash key (/) can be pressed to see a red outline around the contour of the source mask.

  • The bottom left image is the tint image. This layer is created by ChromaStar® and serves to correct spill (color reflected off the green screen onto the subject) and blending (translucent parts of the subject’s clothes which have green showing through it).

  • To the right of the tint image is the tint mask, which can be edited to retouch any debris (ex. dirt, wrinkles, shadows, etc.) on the background.

  • A layer can be hidden by clicking it (a red X will appear) and made visible by clicking it again.

  • Shift-clicking a layer will change which layer a wand selection comes from.

  • To view the image in white overlay mode AND have the wand selection come from the source mask, the shortcut shift+\ can be pressed. Shift+\ can be pressed again to return to your previous layer settings.

  • The buttons to the right of the layers indicate whether the source mask (green screen layer) or the tint mask (background retouch layer) is being edited. Both layers can be edited at the same time by pressing the shortcut ctrl+shift+b.

D - Menu Bar

Save - Saves current image and remains on current image.
Save & exit - Saves current image and returns to PLIC Experience.
Reload image - Reloads the original image to its original state, or, if the image has been saved previously, it will reload to the last saved state.
Exit -
A pop-up will ask if you want to Save and close, Close without saving, or Continue editing the image.

Undo - When a mistake is made, press this to undo the last edit (ex. action, selection, expand, etc.) which was made. A maximum of nine edits can be undone.
Redo - Click this when an edit is undone which you wish to redo. A maximum of nine edits can be redone.
Shortcuts - View editor shortcuts.

Invert - Inverts active selection(s).
Select all - Selects the entire image or mask.
Deselect all - Deselects all active selections.

View with background color - C can be pressed to toggle through six different colored backgrounds to view what the image will look like once a background is placed behind the subject.
Fit to screen - After panning and/or zooming, this can be pressed to reset the size and position of the image to its original state.

About - Shows current version of the software.

E. Status Bar

  • When an image is loaded or saved or when an action is applied, the status bar will tell you whether the task is in process, complete, or if there is an error.

Editor Icon Glossary


Lasso Tool - Used to select small areas of green.

Wand Tool (in the Tool Setting palette) - Used to select green screen.

Wand Tool in Add to Selection mode (on the image)

Wand Tool in Remove from Selection mode (on the image)

Brush Tool

Brush in Show Green mode (in the Tool Settings palette and on the image)

Brush in Hide Green mode (in the Tool Settings palette and on the image)

Add to Selection (used with Lasso and Wand)

Remove from Selection (used with Lasso and Wand)

Hide Green (used with or without an active selection)

Show Green (used with or without an active selection)

Expand or Contract Selection

Invert Selection

Editor Tools

The brush, the lasso, and the wand are the three tools used in PLIC Experience's Green Screen Editor (together with the actions) to edit the images. Each tool has its own Tool Settings which can be adjusted by the imaging technician to fix each image as efficiently as possible while maintaining a high level of quality.

Brush

Brush Settings

  • Size - Default size is 150px. Brush size can be changed by typing a number between 1 and 1500 in the box or by pressing [ to decrease the size and ] to increase the size.

  • Opacity - Brush opacity should be lowered when blending. For example, green hair needs to be blended around the edges and sheer green material which needs to be somewhat transparent can be blended using the brush with a low opacity. Default opacity is 100%. Brush opacity can be changed by eithertyping a number between 0-100 in the box OR by pressing 1 for 10%, 2 for 20% and so on up until 0 for 100%. Opacity can also be changed by pressing ; to decrease opacity and ‘ to increase opacity by increments of 10%.

  • Hardness - A low hardness (low number) will make the edges softer and more blurred, whereas a high hardness (high number) will make the edges appear harder. Default hardness is 90%. Brush hardness can be changed either by typing in a number or pressing { to decrease the hardness and } to increase the hardness by increments of 5%.90% hardness is good in most cases, but it may occasionally need to be lowered when blending (usually when using a low opacity) or when using a really small brush.

Brush Use

  • The Brush Tool is used to hide green from the background which should be extracted and to recover green on the subject which has been hidden by the mask. The two Brush modes (show green and hide green) can be toggled by pressing B or by clicking the icons in the Tool Settings panel.

  • The Brush is the most efficient tool in the following cases: Hiding green around hair, skin, or next to any color which is not green. When blending green hair or blending in sheer green material. To recover green which has been hidden (ex. a shirt which has a very similar green tone as the background, etc.). To hide green around a subject which has a very similar green tone as the background.

Lasso

Lasso Settings

  • Add to Selection - When there is already an active selection and another area needs to be added to the selection, make sure this icon is selected in the Tool Settings palette and then make another selection around the area which needs to be added to the selection.

  • Remove from Selection - When there is already an active selection, but part of the selection needs to be deselected, click on the remove from selection icon (or press and hold alt) and select the area which needs to be removed from the selection.

  • Feather - A small feather (low number) will keep the edges hard, while a larger feather (high number) will soften the edges of the selection. Default feather is 0px. The number of pixels a selection is feathered by can be changed by typing in a number between 0-20.

  • Expand - A negative number will contract an active selection while a positive number will expand an active selection. Default expand is 0px. The number of pixels a selection is contracted or expanded by can be changed by typing in a number between -100 and 100.

  • Hide Green - If pressed with an active selection, the selection will feather and expand by the amounts in the above boxes, and then green will be hidden. If pressed with no active selection, all green on the image will be hidden.

  • Show Green - If pressed when there is an active selection, the selection will feather and expand by the amounts in the above boxes and then green will be recovered. If pressed with no active selection, all green on the image will be recovered.

  • Expand or Contract - When there is an active selection, this can be pressed to expand/contract and feather by the amounts in the above boxes without hiding or showing green.

  • Invert - Used to invert an active selection (expand and feather are not applied).

Lasso Use

  • The lasso tool is used together with the F12 action to quickly edit images which have a small amount of green in a concentrated area. Green which needs to be retained is selected with the Lasso then the F12 action is applied (see more details on the F12 action in the Editor Actions section).

Wand

Wand Settings

  • Add to selection - When there is already an active selection and another area needs to be added to the selection, make sure this icon is selected and click the areas which need to be added to the selection.

  • Remove from Selection - When there is already an active selection but part of the selection needs to be deselected, click on the remove from selection icon (or press and hold the alt key) and click the areas which need to be deselected.

  • Contiguous - When contiguous is checked and the wand is clicked, only adjacent pixels will be selected. Checked by default. When contiguous is unchecked and the wand is clicked, any pixel on the image within a specified range of tones (tolerance) will be selected. Can toggle between having contiguous checked and unchecked by pressing . (period) or by clicking it.

  • Tolerance - Tolerance determines the range of colors which will be selected when the wand is clicked. A smaller number will select a smaller range of colors and a larger number will select a larger range of colors .Can be adjusted by either typing in a number or pressing [ to lower the tolerance and ] to increase the tolerance.

  • Hide Green - If pressed when there is an active selection, the selection will feather and expand by the amounts in the above boxes and then green will be hidden. If pressed with no active selection, all green on the image will be hidden.

  • Show Green - If pressed with an active selection, the selection will feather and expand by the amounts in the above boxes and then green will be brought back. If pressed with no active selection, all green on the image will be shown.

  • Expand or Contract - When there is an active selection, this icon can be pressed to expand/contract and feather by the amounts in the above boxes without hiding or showing green.

  • Invert - Inverts an active selection (expand and feather are not applied).

Wand Use

  • The wand tool is used together with the F10 action to hide background green when it is next to a green subject (ex. shirt, toy, etc.). Background green which needs to be hidden is selected with the wand and then the F10 action is applied to quickly hide the green in all selected areas (see more details on the F10 action in the Editor Actions section).

  • The wand is used together with the g action to hide background green next to green grass. Background green which needs to be hidden is selected with the wand and then the g action is applied to quickly hide the green along the grass (see more details on the g action in the Editor Actions section).

  • It is best to keep contiguous checked and to only uncheck it in the following types of cases (note that when contiguous is unchecked, it is best to use a very low tolerance of about 5-10 to avoid selecting part of the subject. If some of the subject does get selected, it should be removed from the selection with the lasso tool before applying the F10 action): Green crochet sweaters which have the background showing through many of the holes or flowers when they are against the green screen.

Color Brush Tool

To access Color Mode, ctrl+click the tint layer or use the shortcut ctrl+alt+c.

Color Brush Settings

  • Size - Color brush size will be the size of the regular brush size before switching to color brush mode. Brush size can be changed by typing a number between 1 and 1500 in the box or by pressing [ to decrease the size and ] to increase the size.

  • Color Step - Color Step can be increased or decreased to adjust the amount of green which is added or removed from the pixels. Color Step differentiates from Opacity in the following way: With brush opacity, each mouse click will remove/add the specified amount of green but with color step, an area can be painted over up to six times with one mouse click, removing/adding the specified amount of green each time the area is painted over. Default color step is 100. Color Step can be changed in the following ways:Type a number between 0-100 in the box OR press 1 for 10%, 2 for 20%...and 0 for 100%. Press ; to decrease the color step and ‘ to increase the color step by increments of 10%.

  • Hardness - A low hardness (low number) will make the edges softer and more blurred, whereas a high hardness (high number) will make the edges appear harder. Color Brush hardness will be the same as the regular brush hardness before switching to Color Brush mode. Brush hardness can be changed either by typing in a number in the box or by pressing { to decrease the hardness and } to increase the hardness by increments of 5%.

Color Brush Use

  • The Color Brush Tool is used to change the color of the original pixels by either adding or removing green. The two Color Brush modes (add green and remove green) can be toggled by pressing B or by clicking the icons in the Tool Settings panel.

  • The Color Brush should only be used in the following special cases: Removing green from the edges of red or orange hair AND Removing green from sheer material, especially from red, pink, and orange sheer material.

Spill Cleanup Mode

To activate Spill Cleanup Mode, use the shortcut ctrl+alt+r.

Used on objects which become too transparent when green spill is removed.

How to Use

  • Mask the image like normal and then save with ctrl+s.

  • Select the problematic area using the appropriate selection method (wand or lasso)

  • Press ctrl+alt+r to activate the Spill Cleanup Mode.

  • Press delete until the object reaches the desired color. The first time delete is pressed, the selection will contract by 1px, feather by 2px, then fill the selection (this will appear green). The second time delete is pressed, the selection will expand by 1px. All subsequent times delete is pressed, the area selected will start to change color (be careful not too go too far and make the area pink).

  • Deselect.

  • Press ctrl+alt+r to exit the Spill Cleanup Mode.

Note that if multiple areas in an image contain spill, it is best to do each area separately. You must exit and then reactivate the Spill Cleanup mode between each section.

Editor Actions

There are four actions which work together with the tools to help edit the images more efficiently. The F10, F12 and G actions help to hide green, whereas the shift & F12 action helps to recover green which has been partially hidden by the mask.

F10 Action (hide green within selection)

Source Mask (Green Layer)

  • Used together with the wand to hide the background green.

  • Once a selection has been made with the wand, F10 is pressed to expand by 3px, feather by 3px, hide green then go on the brush tool. If pressing F10 once is not enough, it can be pressed again to get even closer to the edge of the subject.

Tint Mask (Background Retouch Layer)

  • Used together with the wand or lasso to hide background debris such as shadows and wrinkles. Once a selection has been made, F10 is pressed to expand by 1px, feather by 1px, hide background debris, then go on the brush tool. If pressing F10 once is not enough, it can be pressed again to get even closer to the edge of the subject.

Both Masks (Background Retouch Mode)

  • Used together with the wand or lasso tool to hide background green and debris at the same time.

  • Once a selection has been made, the F10 action will hide green using expand and feather values of 3px and at the same time it will hide background debris using expand and feather values of 1px, and then go on the brush tool. If pressing F10 once is not enough, it can be pressed again to get even closer to the edge of the subject.

G Action (hide green within selection)

  • Used together with the wand tool to hide the background green next to green grass.

  • This action is the same as the F10 action, except it expands and feathers by 6px each instead of 3px.

  • To use this action, the background must first be selected with the wand. If the selection is next to any green on the subject which is not the grass, minus it from the selection with the lasso tool before pressing g to expand by 6px, feather by 6px, hide green, and go back on the brush tool. If there are any areas next to the grass where the background is still showing too much, use the brush tool with an opacity of 10-20% to touch it up.

F12 Action (hide green outside selection)

  • Used together with the lasso tool to hide the background green.

  • Green within the selection(s) will remain untouched and all green outside the selection(s) will be hidden.

  • Green which needs to be retained is selected with the lasso tool then F12 is pressed to invert the selection, expand by 3px, feather by 3px, hide green, deselect then go back on the brush tool. When needed, multiple areas can be selected with the lasso before applying the F12 action.

Shift & F12 Action (recover green)

  • Used to fill in dark green clothing on areas where the green is not 100% showing.

  • When opened in the editor and viewed in mask overlay mode, green will be seen but with white over-top, meaning that the green color we are seeing in the regular view mode is not the true green color. If too many areas are completely covered with white in the mask overlay mode, meaning they are pure black on the source mask, this action will not be sufficient since it only affects pixels which are not pure black on the source mask.

  • When shift & F12 is pressed it will select all the pixels on the source mask which are not pure black, contract by 2px, feather by 2px, show green (make all the grey pixels pure white on the source mask), select the brush tool and go to the regular view mode. If the green appears blotchy (especially in dark shadow areas), use the brush tool in show green mode to touch it up.

Background Retouch

  • To cleanup the background (wrinkles and shadows) the tint layer must be edited, so start by selecting the button on the right of the tint layer or using the shortcut ctrl+l to toggle between layers.

  • Both the tint layer mask and the source layer mask can be edited at the same time by pressing ctrl+shift+b to select both layer masks. To go back to one layer either press ctrl+shift+b again or press ctrl+l.

  • The same tools (brush, lasso, and wand) and actions (F10 and F12) can be used to retouch the background to hide wrinkles, shadows, dust spots, etc.

  • When using the wand tool, it will by default make a selection from the source image, which is usually where the selection will need to come from (note that even if the selection is coming from the source layer, it is still the tint layer being edited). If it is necessary to have the selection come from a different layer, hold shift and click on the layer where you want the selection to be made.

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