img2lv

ColorFormat

Color format accepted by the conversion functions. Includes the two special request modes AUTO and OPTIMIZED in addition to all concrete LVGL color formats.

Enumeration Members

A1

A1: "A1"

A2

A2: "A2"

A4

A4: "A4"

A8

A8: "A8"

AL88

AL88: "AL88"

ARGB8565

ARGB8565: "ARGB8565"

ARGB8888

ARGB8888: "ARGB8888"

ARGB8888_PREMULTIPLIED

ARGB8888_PREMULTIPLIED: "ARGB8888_PREMULTIPLIED"

AUTO

AUTO: "AUTO"

Automatically pick the smallest indexed tier (I1/I2/I4/I8) based on the number of distinct colors in the source image.

I1

I1: "I1"

I2

I2: "I2"

I4

I4: "I4"

I8

I8: "I8"

L8

L8: "L8"

OPTIMIZED

OPTIMIZED: "OPTIMIZED"

Like AUTO but also merges redundant transparent palette entries so the palette may shrink to a smaller tier.

RAW

RAW: "RAW"

RAW_ALPHA

RAW_ALPHA: "RAW_ALPHA"

RGB565

RGB565: "RGB565"

RGB565_SWAPPED

RGB565_SWAPPED: "RGB565_SWAPPED"

RGB565A8

RGB565A8: "RGB565A8"

RGB888

RGB888: "RGB888"

UNKNOWN

UNKNOWN: "UNKNOWN"

XRGB8888

XRGB8888: "XRGB8888"

---

CompressMethod

Compression method for the binary payload.

Enumeration Members

LZ4

LZ4: "LZ4"

NONE

NONE: "NONE"

RLE

RLE: "RLE"

---

ConvertOptions

Options for converting an image to LVGL format. All fields except cf are optional and fall back to sensible defaults.

Properties

align?

optional align?: number

Stride alignment in bytes (any positive integer). Defaults to 1.

background?

optional background?: number

Background color packed as 0xRRGGBB. Defaults to 0.

cf

cf: "AUTO" | "OPTIMIZED" | "UNKNOWN" | "RAW" | "RAW_ALPHA" | "L8" | "I1" | "I2" | "I4" | "I8" | "A1" | "A2" | "A4" | "A8" | "AL88" | "ARGB8888" | "XRGB8888" | "RGB565" | "ARGB8565" | "RGB565A8" | "RGB888" | "ARGB8888_PREMULTIPLIED" | "RGB565_SWAPPED"

Color format. Accepts any ColorFormat string value (e.g. 'RGB565').

compress?

optional compress?: "NONE" | "RLE" | "LZ4"

Compression method. Accepts any CompressMethod string value. Defaults to 'NONE'.

nemaGfx?

optional nemaGfx?: boolean

Enable Nema GFX compatible output. Defaults to false.

premultiply?

optional premultiply?: boolean

Pre-multiply alpha into RGB channels. Defaults to false.

rgb565Dither?

optional rgb565Dither?: boolean

Enable dithering for RGB565 output. Defaults to false.

---

DecodeOptions

Options for decoding an LVGL image back to a standard format.

Properties

isCArray?

optional isCArray?: boolean

Set to true when the input is a C array produced by imageToC. Defaults to false.

---

imageToBin()

imageToBin(input, options): Buffer

Convert a common image (PNG, JPEG, WebP, BMP, etc.) into an LVGL v9 binary blob that can be written straight to a .bin file.

The returned Buffer starts with the 12-byte LVGL image header followed by the pixel payload (optionally compressed according to options.compress).

Parameters

input

Buffer

options

ConvertOptions

Returns

Buffer

---

imageToC()

imageToC(input, inputName, outputName, options): string

Convert a common image into an LVGL v9 C source file ready for compilation.

inputName is the original filename (used to derive the C variable name when outputName is not provided). The returned string contains the complete .c file text including the lv_image_dsc_t descriptor.

Parameters

input

Buffer

inputName

string

outputName

string | null | undefined

options

ConvertOptions

Returns

string

---

lvglHeight()

lvglHeight(input, options?): number

Read the pixel height from an LVGL image header. Also accepts C array input when options.isCArray is true (not available on the WASM target).

Parameters

input

Buffer

options?

DecodeOptions | null

Returns

number

---

lvglToPng()

lvglToPng(input, options?): Buffer

Decode an LVGL image (binary blob or C array) back to a PNG Buffer.

Accepts either a raw binary blob (12-byte header + payload) or, when options.isCArray is true, a Buffer containing UTF-8 encoded C source text produced by imageToC (e.g. Buffer.from(cSource, "utf8")). Note: C array parsing is not available on the WASM target.

Parameters

input

Buffer

options?

DecodeOptions | null

Returns

Buffer

---

lvglToRgba()

lvglToRgba(input, options?): Buffer

Decode an LVGL image to a raw RGBA pixel buffer (4 bytes per pixel, row-major, no padding).

Like lvglToPng, accepts a binary blob or, when options.isCArray is true, a UTF-8 encoded Buffer of C source text. Note: C array parsing is not available on the WASM target. The buffer length equals width × height × 4. Use lvglWidth / lvglHeight to obtain the dimensions when needed.

Parameters

input

Buffer

options?

DecodeOptions | null

Returns

Buffer

---

lvglWidth()

lvglWidth(input, options?): number

Read the pixel width from an LVGL image header. Also accepts C array input when options.isCArray is true (not available on the WASM target).

Parameters

input

Buffer

options?

DecodeOptions | null

Returns

number