Upscayl is an open-source image upscaling software based on artificial intelligence technology, designed specifically for the Mac platform. Through advanced AI models, it can upscale low-resolution images several times while intelligently repairing blurred details and reducing noise and jagged edges, generating clear and natural high-resolution images. It is especially suitable for scenarios such as photo restoration, digital art, and improving the quality of web images.

1. Detailed Explanation of the Core Interface and Workspace

Upscayl’s interface follows Mac app design conventions, being clean and intuitive, and is mainly divided into four functional areas.

Top Toolbar: Contains the most essential operation buttons, from left to right in order:
- Upscayl Image: The button to select and import the image to be processed.
- Output Folder: Set the save location for the upscaled image.
- Upscayl: The main button to execute the upscaling process.
- Stop: Interrupt the processing task currently in progress.
Left Preview and Settings Panel:
- Input Image: Displays a thumbnail of the imported original image.
- Model Selection: A drop-down menu used to select different AI upscaling models (such as Real-ESRGAN, Remacri, etc.), optimized for different image types (photos, anime, digital art).
- Scale Factor: A scale multiplier selector, typically offering options such as 2x, 3x, 4x, etc.
- Output Format: Select the output image format, such as PNG, JPG, WEBP.
Central Image Comparison View: After processing is complete, this area will display the original image and the AI-upscaled result in a side-by-side or slider comparison, allowing users to intuitively evaluate the detail enhancement.
Bottom Status Bar: Displays the current processing progress, status information (such as “Ready”, “Processing”, “Done”), and the elapsed time.

II. Complete Workflow: From Import to Export

Step 1: Launch the Software and Initial Setup

Double-click Upscayl in “Applications” to open it. When using it for the first time, it is recommended to set the default output folder first.

Location: Click the Output Folder button in the top toolbar.

Specific Method: In the pop-up Finder window, select a folder; all processed images will then be automatically saved there.

Step 2: Import the Original Image

Location: Click the Upscayl Image button on the far left of the top toolbar.

Specific Method: In the Finder window, select one or more images you want to upscale (common formats such as JPG, PNG, and WEBP are supported), and click “Open”. The image thumbnails will be displayed in the “Input Image” area on the left panel.

Shortcut: Command (⌘) + O opens the file selection window directly.

Step 3: Configure Processing Parameters

Make key settings in the left panel, as these directly affect the final result.

Select AI Model: Click the “Model” dropdown menu and choose based on the image content. For example, “Real-ESRGAN” is suitable for general photos, while “Remacri” may provide sharper results.
Set Scale Factor: Click the “Scale” dropdown menu and select, for example, “4x” to enlarge the image to 4 times its original size.
Choose Output Format: Click the “Output Format” dropdown menu and select the save format. PNG is lossless and suitable for further editing; JPG has a smaller file size.

Step 4: Run AI Upscaling

Location: Click the blue Upscayl button in the center of the top toolbar.

Method: After clicking, the software begins processing. The bottom status bar will show “Processing…” and a progress bar. Processing time depends on image size, scale factor, and your Mac’s performance.

Shortcut: Press Command (⌘) + U to start processing directly.

Step 5: Preview and Export Results

Once processing is complete, the status bar shows “Done”.

Preview: The central view area automatically displays a before-and-after comparison. You can drag the slider in the middle to examine detail differences closely.
Export: No extra action needed. The final high-resolution images are automatically saved to the output folder you set in Step 1. File names typically have an “_upscaled” suffix appended to the original file name.

III. Advanced Tips for Common Features

Batch processing: When importing images in Step 2, you can select multiple images at once. The software will automatically process all images in the queue in order, greatly improving work efficiency.
Model experimentation: For the same image, you can try processing it with different AI models and compare the results. Some models perform better when handling specific textures (such as hair or architectural textures).
Moderate upscaling: Higher magnification is not always better. For images with very low quality to begin with, try 2x upscaling first, observe the result, and then decide whether to upscale again to avoid unnatural artifacts produced by AI.
Use previews to optimize your workflow: Before processing a large number of similar images, select one representative image for testing first. Once you find the best combination of model and magnification, apply it to the batch task.

IV. Common Problems and Solutions

Problem 1: Processing speed is very slow

Cause: AI computation has high hardware requirements, especially on Macs lacking Apple Silicon (M-series chips) or a dedicated graphics card.
Solution: Make sure no other large applications are consuming significant CPU/GPU resources; try reducing the upscale factor (e.g., from 4x to 2x); check whether the software is the latest version.

Issue 2: Processed images have strange textures or artifacts

Cause: The AI model “over-interprets” or “hallucinates” certain complex or blurry areas in the original image.
Solution: Switch to a different AI model and reprocess; try reducing the upscale factor; if the original image quality is too poor, first try using other software for basic denoising and repair, then use Upscayl to upscale.

Issue 3: The software cannot open or import images

Cause: The image format is not supported or the file is corrupted; software permission issues.
Solution: Confirm the image format is a common format (JPG, PNG, WEBP); try opening the image with Preview and saving it as a standard format; in “System Settings” > “Privacy & Security,” make sure Upscayl has been granted disk access permission.

Issue 4: Cannot find images in the output folder

Cause: The output path is set incorrectly or the saving process was interrupted.
Solution: Click the “Output Folder” button again to confirm the path; during processing, check whether the status bar shows the “Done” completion status; use the search function in Finder to search by filename (e.g., _upscaled).

V. Upscayl for Mac Keyboard Shortcuts Summary

Function	Shortcut (Mac)	Description
Open/Import Image	`⌘ + O`	Pops up the file selection window
Start Processing Image	`⌘ + U`	Executes AI upscaling
Stop Processing	`⌘ + .`	Interrupts the current processing task
Hide/Show App	`⌘ + H`	Hides the window to the Dock
Quit App	`⌘ + Q`	Completely closes Upscayl
Switch Focus Between Model Selection Boxes	`Tab`	Switches focus between input fields and buttons on the interface

Tip: As a tool primarily operated with graphical buttons, Upscayl has relatively limited keyboard shortcuts. The key to efficient use lies in familiarizing yourself with the workflow and reasonable parameter presets.