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Corridor Chroma

Updated July 4, 2026Open the tool

Open Corridor Chroma

Corridor Chroma is an AI green screen removal tool for turning keyed images into transparent PNG assets. Upload one or more green screen images, choose or sample the screen color, adjust tolerance, preview the alpha mask, then process the images for use in games, compositing, UI art, sprites, cutouts, and WizardGenie projects.

What it does

Corridor Chroma removes green backgrounds from still images and outputs PNG files with transparency. It is designed for subjects photographed, rendered, or generated against an evenly lit green backdrop.

The tool combines manual chroma key controls with AI-assisted foreground extraction. You can process a single image or a batch, review finished cutouts in a gallery, open any completed result in a fullscreen preview, and download individual images or the most recent batch.

Key features

  • Green screen background removal — removes green backdrops and creates transparent PNG assets.
  • Single-image or batch workflow — upload one file for a quick cutout, or queue multiple images and process them together.
  • Auto-detected screen color — Corridor Chroma samples the first queued image and attempts to detect the dominant screen color automatically.
  • Manual color selection — choose a color with the color picker, enter a hex value, or sample directly from an uploaded image with the eyedropper.
  • Tolerance control — adjust how tightly or loosely the selected green is removed.
  • Alpha preview — preview the mask before processing. Black areas are removed; white areas are kept.
  • Green despill toggle — reduce green edge spill, or preserve original colors when the subject contains intentional green.
  • Cloud GPU and Local GPU modes — process through Sorceress cloud processing, or use a configured local GPU server.
  • Recent Results panel — quickly review and download the latest processed set.
  • Persistent gallery for signed-in users — recent Corridor Chroma results are loaded back into the gallery when you return.
  • WizardGenie embed support — when opened inside WizardGenie, completed images can be dragged into the WizardGenie Explorer.

Requirements and limits

Input files

Corridor Chroma accepts image uploads through the file picker, drag and drop, and compatible Sorceress image hand-offs.

The upload area shows support for:

  • PNG
  • JPG / JPEG
  • WebP

Each uploaded file must be 5 MB or smaller. Files over the limit are skipped and listed in an error message.

Green screen only

Corridor Chroma is made specifically for green screen images. Blue screens and other backdrop colors are not supported. For best results, use an evenly lit green background with clear separation between the subject and backdrop.

Cloud GPU resolution limit

When using Cloud GPU, uploads are automatically resized before processing to a maximum of 1024 px on the longest side. If the source image is small, it may be processed at a smaller working size.

If you need larger output, use Local GPU.

Local GPU requirement

Local GPU mode requires a local processing server configured from Sorceress Settings. The interface states that local processing requires an NVIDIA GPU with CUDA and 6 GB or more VRAM.

Typical workflow

  1. Open Corridor Chroma.
  2. Upload one or more green screen images:
    • Click the upload box to browse, or
    • Drag and drop images into the upload area.
  3. Review the queued images in the Ready section.
  4. Check the detected Screen Color.
    • If auto-detection worked, the color is labeled Auto-detected.
    • If needed, adjust it manually with the color controls.
  5. Adjust Tolerance.
  6. Choose whether Green Despill should be on or off.
  7. Review the Alpha Preview if it appears.
  8. Choose Process With:
    • Cloud GPU for cloud processing.
    • Local GPU if your local server is configured and connected.
  9. Click:
    • Remove Green Screen for one queued image, or
    • Process All Images for a batch.
  10. Review results in the gallery and Recent Results panel.
  11. Download completed PNGs individually, or use Download All for the recent set.

Processing appears in the gallery while it runs, and the upload controls remain usable while active work is shown.

Uploading and managing the queue

The left upload panel contains the upload area and all chroma key controls. Queued files appear as thumbnails under Ready.

From the queue you can:

  • Add images by clicking the upload zone.
  • Add images by dragging and dropping them onto the upload zone.
  • Remove an individual queued image with its thumbnail remove button.
  • Clear the full queue with Clear.
  • Use queued thumbnails as eyedropper targets when picking the screen color.

If more than one file is queued, Corridor Chroma shows a batch processing button. If only one file is queued, it shows the single-image Remove Green Screen button.

Screen color controls

The Screen Color section controls which green is treated as the removable background.

Auto-detected color

After you upload images, Corridor Chroma attempts to detect a key color from the first queued image. If the tool is confident enough, it applies that color automatically and labels it Auto-detected.

For batches, Corridor Chroma also attempts to adjust the key color per image during processing. This helps when a batch has slight lighting differences between files.

Color picker

Use the color swatch to choose the green screen color manually. Changing the color this way marks the selection as Manual.

Hex color field

You can enter a six-digit hex color, such as #00b140. The default green shown by the tool is #00b140.

The field only accepts complete six-digit hex colors. If a partial or invalid value is entered, the current color is not changed.

Eyedropper

Use Pick to sample the screen color directly from an uploaded image.

  1. Click Pick.
  2. The button changes to Click..., and queued thumbnails become eyedropper targets.
  3. Click a representative area of the green background in a queued thumbnail.
  4. The selected color is applied and marked as Manual.

For best results, click an evenly lit area of the background. Avoid shadows, highlights, edges, motion blur, compression artifacts, and areas where the subject overlaps the screen.

Tolerance

Tolerance controls how broad the color match is.

  • Lower values are Tight and remove colors closer to the selected green only.
  • Higher values are Loose and remove a wider range of green shades.

The available range is 10 to 200. The default value is 80.

Use a tighter tolerance when the subject contains green details that should be preserved. Use a looser tolerance when the screen is unevenly lit or has shadows, wrinkles, gradients, or slight color variation.

Green Despill

Green Despill controls whether Corridor Chroma reduces green color spill around the subject.

  • On — removes green spill from edges. This is usually best for clean compositing, but it may shift intentional green colors in the subject.
  • Off — preserves original colors. This is best when the subject contains green clothing, props, foliage, UI elements, or other green details.

Despill is enabled by default.

Alpha preview

When a screen color has been selected and images are queued, Corridor Chroma shows an Alpha Preview for the first queued image.

The preview is a mask:

  • Black = removed
  • White = kept

Use the preview to tune the screen color and tolerance before processing. If important subject areas appear black, lower tolerance or choose a more accurate screen color. If background remains white, raise tolerance or pick a better sample from the background.

The alpha preview is a guide for the chroma selection. The final AI-assisted result may be cleaner than the preview, especially around hair, soft edges, and semi-complex contours.

Processing modes

Cloud GPU

Cloud GPU is the default cloud processing option for signed-in users. It does not require local setup.

Important details visible in the tool:

  • Requires you to be signed in.
  • Shows the total processing amount for the queued images before processing.
  • Automatically resizes uploads to a maximum of 1024 px on the longest side before green screen removal.
  • If your account cannot process the requested batch, Corridor Chroma shows an error dialog.

Use Cloud GPU when you want the easiest setup and your desired output size fits the cloud resolution limit.

Local GPU

Local GPU uses a local processing server configured in Sorceress Settings.

Important details visible in the tool:

  • Shown as Free in the Local GPU panel.
  • Requires the local server to be online and connected.
  • Requires an NVIDIA GPU with CUDA and at least 6 GB VRAM.
  • Can be used when you need larger output than the Cloud GPU limit.
  • The interface displays local connection states such as Checking..., Local server connected, Loading model..., and Local server offline.

If Local GPU is selected and the server is offline, the process button is disabled until the local server is connected. Use the refresh button in the Local GPU status area to check again. If the local server is not set up, use the Set up local server in Settings link shown in the panel.

Working with results

Completed images appear in the central Processed Images gallery. Newly processed images also appear in the right-side Recent Results panel.

From the main gallery you can:

  • Click a completed image to open it in a fullscreen lightbox.
  • Download an individual PNG.
  • Delete a result.
  • Adjust the desktop gallery density with the Grid slider.
  • See how many completed images are currently in the gallery.
  • Remove stuck processing entries with Clear stuck if any are still shown as processing.

Transparent areas are displayed on a checkerboard background so you can evaluate the cutout.

During processing, a gallery tile shows a spinner and a Cancel option. Failed items show a failure message and can be removed.

Recent Results panel

The Recent Results panel shows the latest images processed during the current session. From this panel you can:

  • Review the most recent set as thumbnails.
  • Open completed results in the fullscreen lightbox.
  • Use Download All to download all completed images in the recent set.

Batch downloads use the original file name when available and append a chroma suffix.

Fullscreen lightbox

Click a completed gallery image to open the fullscreen preview. From the lightbox you can:

  • View the transparent PNG on a larger checkerboard background.
  • Download the result as a PNG.
  • Delete the result.
  • Navigate between completed images with the left and right arrow buttons.
  • Use the keyboard: Left Arrow, Right Arrow, and Escape.
  • Close the lightbox by clicking the close button or the dark background.

When Corridor Chroma is opened inside WizardGenie, the lightbox also shows a Drag to WizardGenie Explorer control for completed images.

WizardGenie hand-off

Corridor Chroma supports WizardGenie embed workflows. When opened inside WizardGenie, completed images can be dragged into the WizardGenie Explorer. This is useful for turning generated green screen renders into transparent assets and immediately using them in a WizardGenie project.

In embedded mode:

  • Completed gallery items can be dragged.
  • Completed lightbox images show a drag control.
  • Incomplete or failed items cannot be dragged.

Mobile layout

On mobile, Corridor Chroma uses two slide-out panels:

  • Upload — opens the upload queue, chroma key controls, processing mode, and process button.
  • Results — opens the recent results panel.

The processed image gallery remains the main page area. Tap the active tab again or tap outside an open panel to close it.

Saving, deleting, and returning later

Signed-in users see recent Corridor Chroma results loaded back into the gallery when returning to the tool. The gallery displays up to the most recent saved results for this tool.

You can delete a result from the gallery or lightbox. Deleting removes it from the visible Corridor Chroma gallery for your account.

If you are not signed in, the tool may show demo content or temporary session results, but Cloud GPU processing requires sign-in.

Tips for better results

  • Use an evenly lit green screen with minimal wrinkles, shadows, or gradients.
  • Keep the subject separated from the green backdrop to reduce spill and edge contamination.
  • Avoid green subjects when possible, or turn Green Despill off if green details are important.
  • Use the eyedropper on the actual background color in your image rather than relying only on the default green.
  • Pick a mid-tone green area, not an edge, shadow, highlight, or compressed blocky region.
  • Check the Alpha Preview before processing a large batch.
  • Increase tolerance if green remains in the background or around the subject.
  • Decrease tolerance if parts of the subject disappear.
  • For high-resolution assets, use Local GPU instead of Cloud GPU.
  • For mixed batches with different lighting, inspect the results and reprocess difficult images separately with adjusted settings.

Troubleshooting

The process button says I need to sign in

Cloud GPU processing requires a signed-in Sorceress account. Sign in, then try again. If you have a configured Local GPU server, select Local GPU instead.

My file was skipped

The file may be larger than 5 MB or may not be recognized as an image. Export a smaller PNG, JPG, or WebP and upload again.

The alpha preview does not appear

The alpha preview appears after a screen color has been selected and at least one image is queued. If it does not appear, try selecting the color manually with the color picker or eyedropper.

The background is not fully removed

Try one or more of the following:

  • Use the eyedropper to pick a better green sample.
  • Increase Tolerance.
  • Choose a flatter, more evenly lit source image.
  • Process the image separately instead of in a mixed batch.

The subject is being cut out

Lower Tolerance or pick a green sample from a clean background area instead of an edge or shadow. If the subject contains green, turn Green Despill off.

Edges have a green outline

Keep Green Despill on and try a slightly higher tolerance. If the green outline is caused by strong lighting spill, a cleaner source image may be needed.

Green areas in my subject changed color

Turn Green Despill off. Despill is useful for edge cleanup, but it can affect intentional greens in the subject.

Local GPU says offline

Make sure your local processing server is running and configured in Sorceress Settings. Then click the refresh button in the Local GPU status area. Local GPU mode requires a compatible NVIDIA CUDA GPU with at least 6 GB VRAM.

Local GPU says loading model

Wait for the model to finish loading. Corridor Chroma checks again automatically while Local GPU mode is selected, and you can also use the refresh button.

A processing item appears stuck

If a processing item remains in the gallery, use Clear stuck in the gallery header to remove stuck processing entries from the view.

FAQ

Does Corridor Chroma support blue screens?

No. The tool explicitly states that blue screens and other backdrop colors are not supported. It is designed for green screen images.

What format are downloads?

Completed results are downloaded as PNG files with transparency.

Can I process multiple images at once?

Yes. Upload multiple images, review the settings, then click Process All Images.

Can I use Corridor Chroma with a local GPU?

Yes, if you have configured a compatible local processing server in Sorceress Settings. The tool requires the local server to be connected before Local GPU processing can start.

Why is my Cloud GPU result smaller than the original?

Cloud GPU automatically resizes uploads to a maximum of 1024 px on the longest side before processing. Use Local GPU if you need larger output.

Are my previous results saved?

For signed-in users, recent Corridor Chroma results are loaded back into the gallery when you return to the tool. You can delete results from the gallery or lightbox.

Can I send results to WizardGenie?

Yes. When Corridor Chroma is opened inside WizardGenie, completed images can be dragged into the WizardGenie Explorer.