Effects

Effects are modifiers applied to layers. Each layer type accepts a specific set.

Effect	Text	Image	Shape	Background
Stroke	✓	✓	✓	—
Shadow	✓	✓	✓	—
Glow	✓	✓	✓	—
Filter	—	✓	—	✓
Background	✓	—	—	—
Grain	—	✓	—	✓

Pass effects as a list to the effects parameter of any layer:

from quickthumb import Shadow, Stroke

canvas.text(
    content="CLICK NOW",
    size=96,
    color="#FFFFFF",
    effects=[
        Stroke(width=4, color="#000000"),
        Shadow(offset_x=4, offset_y=4, color="#000000", blur_radius=8),
    ],
)

---

Stroke

Draws an outline around text glyphs, image edges, or shape edges.

from quickthumb import Stroke

Stroke(width=4, color="#000000")

Parameter	Type	Description
width	int	Stroke thickness in pixels. Positive integer.
color	str	Stroke color. Hex string ("#RRGGBB" or "#RRGGBBAA").

Example

from quickthumb import Stroke, TextPart

canvas.text(
    content=[
        TextPart(text="BIG TEXT", color="#FFFFFF", effects=[Stroke(width=6, color="#000000")]),
    ],
    size=108,
    position=("8%", "50%"),
    align=("left", "middle"),
)

---

Shadow

Adds a drop shadow offset from the layer.

from quickthumb import Shadow

Shadow(offset_x=4, offset_y=8, color="#000000", blur_radius=12)

Parameter	Type	Default	Description
offset_x	int	required	Horizontal shadow offset in pixels. Can be negative.
offset_y	int	required	Vertical shadow offset in pixels. Can be negative.
color	str	required	Shadow color. Hex string.
blur_radius	int	0	Blur spread in pixels. Non-negative integer.

Example

from quickthumb import Shadow

canvas.image(
    path="portrait.png",
    position=("74%", "54%"),
    width=420,
    height=520,
    effects=[Shadow(offset_x=0, offset_y=14, color="#000000", blur_radius=24)],
)

---

Glow

Adds a soft colored halo around the layer.

from quickthumb import Glow

Glow(color="#B8FF00", radius=16, opacity=0.35)

Parameter	Type	Default	Description
color	str	required	Glow color. Hex string.
radius	int	required	Glow spread radius in pixels. Positive integer.
opacity	float	1.0	Glow intensity from 0.0 to 1.0.

Example

from quickthumb import Glow

canvas.text(
    content="ELECTRIC",
    size=96,
    color="#FFFFFF",
    effects=[Glow(color="#22d3ee", radius=24, opacity=0.5)],
)

---

Filter

Applies image processing adjustments. Used on background layers and image layers.

from quickthumb import Filter

Filter(blur=4, brightness=0.75, contrast=1.1, saturation=0.9)

Parameter	Type	Default	Description
blur	int	0	Gaussian blur radius. Non-negative integer.
brightness	float	1.0	Brightness multiplier. Positive float. 1.0 = no change, 0.5 = half brightness.
contrast	float	1.0	Contrast multiplier. Positive float. 1.0 = no change.
saturation	float	1.0	Saturation multiplier. Non-negative float. 0.0 = grayscale, 1.0 = no change.

All parameters default to neutral — only set the ones you want to change.

Example

from quickthumb import Filter

canvas.background(
    image="hero.jpg",
    fit="cover",
    effects=[Filter(blur=6, brightness=0.6, saturation=0.8)],
)

---

Background (text fill)

Draws a filled rounded rectangle behind a text block. Only available on text layers.

from quickthumb import Background

Background(color="#111827CC", padding=(16, 24), border_radius=14, opacity=1.0)

Parameter	Type	Default	Description
color	str	required	Fill color. Hex string ("#RRGGBB" or "#RRGGBBAA").
padding	int \| tuple	0	Inner padding. int for uniform, (vertical, horizontal), or (top, right, bottom, left).
border_radius	int	0	Corner rounding in pixels. Non-negative integer.
opacity	float	1.0	Fill opacity from 0.0 to 1.0.

Example

from quickthumb import Background

canvas.text(
    content="BREAKING NEWS",
    size=72,
    color="#FFFFFF",
    position=("8%", "50%"),
    align=("left", "middle"),
    effects=[
        Background(color="#CC0000", padding=(12, 20), border_radius=8),
    ],
)

Note

Background as an effect is separate from the .background() layer builder. The effect applies behind a text block; the layer covers the full canvas.

---

Grain

Adds film-grain noise to a background or image layer.

from quickthumb import Grain

Grain(intensity=0.12, monochrome=True, blend_mode="overlay", opacity=1.0)

Parameter	Type	Default	Description
intensity	float	required	Noise amplitude from 0.0 (none) to 1.0 (maximum).
monochrome	bool	True	True = luminance noise (grey grain); False = independent per-channel color noise.
blend_mode	str	"overlay"	How noise composites onto the layer. One of "overlay", "screen", "multiply", "normal".
opacity	float	1.0	Overall grain strength from 0.0 (invisible) to 1.0 (full).
seed	int \| None	None	RNG seed for deterministic output. None = random each render.

intensity=0.0 is a no-op — no noise is generated.

Example

from quickthumb import Canvas, Grain

canvas = (
    Canvas(1280, 720)
    .background(
        color="#1A1A2E",
        effects=[Grain(intensity=0.12, monochrome=True)],
    )
    .image(
        path="portrait.png",
        position=("70%", "50%"),
        width=400,
        height=500,
        align=("center", "middle"),
        effects=[Grain(intensity=0.08, monochrome=False, blend_mode="overlay", opacity=0.6)],
    )
)

Note

Grain is valid only on background and image layers. It is not available on text or shape layers.