Published: Oct 15, 2026Last updated: Oct 15, 2026

Editing artwork in FireAlpaca with just a mouse

FireAlpaca Painting app Mouse Image editing Hand-drawn Avatar

12 min read

If you know the features of a painting app, you can edit artwork with just a mouse.

The FireAlpaca window. In the middle of the canvas, a character image with a transparent background — The FireAlpaca window

In the previous article, I wrote about touching up an AI-generated image to make a streaming avatar, but I skipped how to use a painting app. It seems quite a few people who want an avatar for PNGTubing have never used a painting app, so this time the focus is on “drawing with a mouse”. I will use an avatar for Peraravatar+ as the example, but this is basically a guide to FireAlpaca. Most other painting apps have the same basic features, so you can apply it there too.

Making a streaming avatar with Peraravatar+ Making a streaming avatar with the Peraravatar+ PNGTuber: a blank-face base from one AI image, presets for a quick start, your own eye and mouth parts, and a bouncing chest and swinging accessories. GyunGyun×Create (gyungyun.com)

This time, I will show how to prepare an avatar for Peraravatar+ with just a mouse. There are people who draw with a mouse, so-called “mousers”, so once you get the hang of it, you can do most things without a pen tablet. I used to be a mouser myself. Do not give up — give it a try. If you use ibisPaint on a tablet, that app can handle all of this, so you are on your own there.

Installing

FireAlpaca is free, for both personal and commercial use.

Open the FireAlpaca download page
Download the Windows version (Windows 10 or later) or the Mac version (macOS 12 or later)
Open the downloaded file and follow the on-screen instructions to install it

There is also a paid version, FireAlpaca SE, but everything in this article can be done with the free version.

The screen

When you start FireAlpaca, a screen like this appears. The screenshots in this article show the Japanese interface.

FireAlpaca right after starting. Red frames mark ① the tool icons on the left edge, ② the Color and Color Palette windows, ③ windows such as Brush Control and Brush, ④ the tool settings under the menu, and ⑤ the Layer window at the bottom right. The middle is gray — FireAlpaca right after starting

This screenshot was taken after I rearranged things like the brush size for my own use, so the exact layout will probably differ from the image above. For now, just get a rough idea of what is where.

	Area	What it does
①	Tools	Switch between tools such as brush, eraser and selection
②	Color, Color Palette	Choose the color to draw with
③	Brush Control, Brush, etc.	Settings such as brush size, type and opacity
④	Tool settings	Settings for the selected tool. The items change when you switch tools
⑤	Layer	Add layers and switch them between shown and hidden

You do not need to memorize which icon in ① is which tool. Hover over an icon and the tool name appears.

Hovering over the brush icon on the left edge shows the name Brush Tool — Hover over an icon to see the tool name

If you accidentally close a window with the ✕ button at its top right, you can show it again from the Window menu.

Opening the image

First, open the AI-generated image.

Choose the image with File → Open, or drag and drop the image from a folder onto the FireAlpaca window.

An image opened in FireAlpaca. On the canvas, a chibi girl with purple hair, cat ears and a maid headdress stands on a white background. The Layer window has one layer, Layer1 — The opened image. This time I use a chibi version of the character from the previous article

Removing the background

First, to make leftover spots easier to find, put a layer filled with a dark color under the image.

Press the leftmost button in the Layer window to add a new layer (Layer2)
Drag Layer2 below the image layer (Layer1)

The Layer window. An empty Layer2 has been added below Layer1, which holds the character image, and is selected — The new layer moved below the image layer

With Layer2 selected, choose the bucket icon on the left edge (Bucket Tool)
In the Color window, choose a dark color that is not used in the character. I chose a dark green
In the tool settings at the top, set Reference to Active Layer

The Bucket Tool selected with a dark green color. The Reference list in the tool settings is open, with Active Layer chosen from Canvas, Active Layer and Specified Layer — Set Reference to Active Layer

Click the canvas. The whole new layer is filled with green

The Layer window. The thumbnail of Layer2 below Layer1 is solid green — The whole lower layer filled with green

Next, select the background.

Choose the magic wand icon on the left edge (MagicWand Tool). Set Reference in the tool settings to Canvas
Click the background

Tolerance is the value that sets how close a color must be to the clicked color to be selected along with it. The white background of an AI-generated image is not pure white when you look closely; the color varies slightly, so with Tolerance left at 1, the background gets selected in patches.

The background clicked with the MagicWand Tool at Tolerance 1. Only the left side of the background is selected, in patches of white and black dots — Selected with Tolerance left at 1

Raise this value little by little and find the value that selects just the background cleanly. Raise it too far and the white clothes and wings get selected too. To select again, clear the selection with Ctrl + D and click the background again. This time I set Tolerance to 7.

The background clicked at Tolerance 7. A dotted line runs along the edge of the character, and the whole background is selected — Selected at Tolerance 7

Small missed spots still remain, so switch to the select pen and paint over them.

Choose the icon right below the magic wand on the left edge (SelectPen Tool). With the select pen, the selected area is shown in color
Zoom in and out with the mouse wheel and look around the edges
When you find white background without color (a missed spot), click to paint it into the selection. Paint small spots while changing the brush size. If you make a mistake, undo with Ctrl + Z

Redo: If you undo too far, redo with Ctrl + Y.

The ribbon at the feet zoomed to 800% with the SelectPen Tool. The background selection is shown in red, and a few white dots remain outside the edge of the sock — Missed spots remain outside the edge of the sock

Watch out for narrow gaps between lines. The selection does not reach deep into the corners, so paint them by hand.

The tip of the ribbon and hair, zoomed in with the select pen. The background is selected in red, but white remains deep in the corner where two lines meet at a sharp angle — Narrow gaps are not selected automatically

In the Layer window, click the image layer (Layer1) and press Delete to remove the background. Be careful: if you press Delete with Layer2 still selected, the selected area is removed from the green Layer2 instead
Deselect with Ctrl + D

The background disappears and the green below shows through. However, background enclosed by lines, such as the gaps between strands of hair, is still white.

The background removed, with the green layer below showing. The area around the character is green, but white background remains in places such as the gaps between strands of hair — The background removed. The background between strands of hair is not removed yet

For the gaps in the hair too, select them with the MagicWand Tool, paint the missed spots with the select pen, and remove them with Delete. It is a repeat of steps 7–13

Selecting several areas: With the MagicWand Tool, click while holding Shift to select several areas at once. Click while holding Ctrl to remove that area from the selection.

Sometimes a faint color remains even after you press Delete. The cause is anti-aliasing. Anti-aliasing is a feature that adds partly transparent color along edges to make them look smooth.

Two black vertical lines drawn on a transparent background, zoomed in. The left line, with anti-aliasing on, has gray along the edges and looks smooth. The right line, with it off, has jagged edges — Anti-aliasing ON on the left, OFF on the right

Anti-aliasing also applies to the select pen. When it is ON, the painted area becomes only faintly selected. In a faintly selected area, the color does not disappear completely when you press Delete.

The images below show a single click on the center pixel with the select pen (brush size 1) with anti-aliasing ON. After one click, the pixel is only faintly selected. Each click makes the selection color darker, and after about five clicks it ends up the same as painting with anti-aliasing OFF.

Zoomed in to individual pixels. The center pixel, clicked once with the select pen, is light pink — One click

After clicking the same spot five times. The center pixel is dark pink — Five clicks on the same spot

Anti-aliasing is ON by default, so switch it OFF as needed.

The tool settings with the Brush Tool selected. To the right of Snap, Shape and Symmetry is the Anti-aliasing (Global) checkbox, which is checked — Anti-aliasing (Global) in the tool settings

If small areas are still left after removing the selection with Delete, erase them with the Eraser Tool.

Select and delete, or erase: Both do the same thing. When the area to remove is large, like a background, selecting it and pressing Delete is easier. Small spots are not worth selecting, so erase them directly with the eraser.

The background fully removed. Everything around the character, including the gaps between strands of hair, shows the green of the layer below — The background fully removed

Hide the green layer in the Layer window

The green layer hidden. The background around the character shows a checkerboard pattern, meaning it is transparent — The green layer hidden

Save often: Save often. The image you opened is still a PNG, so if you save it as is with File → Save, it overwrites the original image and the layers are not kept. The first time, use File → Save As and choose the FireAlpaca format (.mdp). From then on, File → Save (Ctrl + S) overwrites the .mdp.

Polishing the artwork

AI-generated images have odd spots when you look closely. This time, the spots circled in red bothered me. If small details like these do not bother you, you can skip this part.

The character image with the background removed, with spots that bother me circled in red: the right cat ear, both eyebrows and the bangs, beside the right cheek, the choker clasp, the hair tip on the left shoulder, and between the hair and wing on the right shoulder — The spots that bothered me this time

From a distance you can barely tell, so leaving them is fine. If you plan to use this avatar for chatting streams with your face in close-up, I think fixing them is a good idea. Personally, the jagged lines in images generated by ChatGPT bother me, especially in the bangs. On top of that, there are mystery lines that look like something was half-drawn and abandoned, and messed-up strands of hair — plenty that a perfectionist cannot stand.

Fixing the jagged bangs

Add a layer above the image layer
Choose the brush icon at the top of the left edge (Brush Tool)
Zoom in with the mouse wheel
Right-click near the spot you want to paint to pick up its color. With the Brush Tool still selected, a right-click picks up color like the eyedropper
With the picked color, dab away with the mouse. When you reach a spot where the color changes, right-click to pick the color again

You are not painting directly on the original image, so if you make a mistake, you can go back by erasing the added layer with the eraser. Here is the result of partly fixing the bangs.

The bangs and eyebrows zoomed to 600%. The edges of the lines in the bangs are jagged — Before

The same spot after painting over it on the layer above. The edges of the lines in the bangs are smooth — After

If you want to draw lines instead of dabbing, crank up Stabilizer (Global) in the tool settings. Even the max of 100 is fine. That way, your lines will not get jagged even when you draw slowly.

The Stabilizer (Global) list in the tool settings, open. Values from 0 to 100 are listed, with 80 selected — The stabilizer value can be set from 0 to 100

As a test, I drew hearts with a mouse at stabilizer 0, 20, 40, 80 and 100. My mouser skills turned out higher than I expected, so it may be hard to see, but the higher the value, the smoother the line. People with a pen tablet often adjust it between 0 and 50 depending on the kind of line they want. For a mouser, stabilizer 0 gives a super jagged line. Set it to 100 and draw slowly. The line follows slowly, but you can draw smoothly right where you want.

Five hearts drawn with a mouse at stabilizer 0, 20, 40, 80 and 100, each with its value written inside. The higher the value, the less jagged the line — Hearts drawn at stabilizer 0, 20, 40, 80 and 100, from left

On top of that, checking Zero Pressure on Both Ends next to the stabilizer makes the start and end of each line thinner, so the line looks like it was drawn with a pen tablet. Using this, you can draw an eye like this even with a mouse.

Lines drawn with a mouse with Zero Pressure on Both Ends checked. On the left, four arcs of different thickness, all thin at both ends. On the right, an eye with lashes and an iris outline drawn with the same lines — A line and an eye drawn with a mouse, with Zero Pressure on Both Ends checked

If you can only draw so-so lines even with the stabilizer, use the Curve shape.

With the Brush Tool selected, check Shape in the tool settings and choose Curve from the list next to it

Shape checked in the tool settings, with the list next to it open. Line, Polyline, Polygon, Rectangle, Square, Ellipse, Circle, Super Ellipse, Curve and a closed curve are listed, and Curve is chosen — Check Shape and choose Curve

Trace the curve you want to draw by clicking along it
Double-click to confirm. The line is drawn at the thickness of the selected brush

Tracing a curve along a line of the bangs by clicking. A thin curve follows the edge of the bangs — Tracing a curve along a line of the bangs by clicking

A line of the bangs redrawn with the Curve shape. The line is a single dark purple that does not match the surrounding hair — A line of the bangs drawn with Curve

Zero Pressure on Both Ends does not work on lines drawn with the Curve shape. The line has the same thickness from start to end.

A curve can only be drawn in one color, so match the color of the line to its surroundings afterward.

Check Protect Alpha in the Layer window. You can no longer paint anywhere except where the line is drawn

The Layer window. Layer4, with the line on it, is selected, and Protect Alpha is checked — Check Protect Alpha

Pick up the colors of the surrounding bangs with a right-click and paint parts of the line

The line of the bangs repainted. Near black at the root and light purple at the tip — Painted near black at the root and light purple at the tip

Use these steps to fix whatever bothers you across the whole image.

The character image after fixing the spots that bothered me across the whole image. The background is transparent — After the fixes

Making a blank face

Paint over the eyes and mouth of the original image with the skin color.

In the Layer window, select the original image layer and duplicate it with Layer → Duplicate. From here on, work on the duplicate
With the Brush Tool still selected, right-click to pick up the skin color around the eyes, and dab it over the eyes. The skin color varies by spot, so pick it up again each time

Skin color picked up from the surroundings dabbed over where the eyes were. The eyes are gone, but the borders between the dabbed colors look patchy — The skin color around the eyes dabbed on

As is, it does not blend in, so choose the Blur brush in the Brush window and raise Blur Intensity in the Brush Control window

The Blur brush chosen in the Brush window, with Blur Intensity in the Brush Control window set to 100 — Choose Blur and raise Blur Intensity

Go over the dabbed colors to blend them together with the blur

The cheek area after going over it with the Blur brush. The borders between the dabbed colors are gone, and the skin color flows smoothly — The colors blended together with the blur

Remove the mouth the same way
Hide the original image layer and the green layer in the Layer window
Choose File → Export, then the top item of the submenu that appears

Hovering over Export in the File menu and choosing the top item of the submenu that appears — Export in the File menu

In the Export Settings dialog box, choose Transparent PNG as the File Format and press OK

The Export Settings dialog box, with Transparent PNG chosen as the File Format — Choose Transparent PNG as the File Format

Choose where to save and the file name, then press Save

The character image made into a blank face, with the eyes and mouth painted over in skin color. The eyebrows remain, and the background is transparent — The blank-face image

Cutting out an eye

Cut out one eye from the original image to use as a part.

Select the original image layer in the Layer window
With the dotted-rectangle icon on the left edge (Select Tool), drag a rectangle around the left eye
Copy with Ctrl + C
With File → New, set the width and height to 200 to make a 200 × 200 canvas
Paste the copied eye with Ctrl + V
The pasted eye stays where it was in the original image, so choose Layer → Move → Align Center to move it to the center

The eye pasted onto a 200 × 200 canvas. Hovering over Move in the Layer menu and choosing Align Center from the submenu that appears — Layer → Move → Align Center

Save it as a transparent PNG with File → Export

Even if some skin remains around the cut-out eye, it blends in once you place it over the eye position of the base image in Peraravatar+, so you do not need to clean it up perfectly.

Apart from using a mouse, everything else is the same as in the previous article.

Summary

When the area to remove is large, select it and delete; erase small spots directly with the eraser
Tolerance is the value that sets how close a color must be to the clicked color to be selected along with it
Anti-aliasing is a feature that adds partly transparent color along edges to make them look smooth
For small spots, zoom in with the mouse wheel and dab
To draw lines, raise the stabilizer value or use the Curve shape
With Protect Alpha checked, you can only paint where something is already drawn
Work on separate layers. If you make a mistake, you can go back by removing that layer
Save often

Categories FireAlpaca Painting app Mouse Image editing Hand-drawn Avatar

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