BMP)

See AxlGfx — Graphics for an overview of the graphics substrate. AxlPixmap decodes encoded image byte buffers into AxlGfxBuffer pixel arrays for blit-style consumption (icons, button bitmaps, CSS <img> and background-image).

Header: <axl/axl-pixmap.h>

Backed by stb_image vendored at deps/stb/stb_image.h (dual MIT / Public Domain licensed). Two entry points:

axl_pixmap_info returns dimensions without decoding — for layout-driven container sizing before committing to a full pixel-buffer allocation.
axl_pixmap_decode returns a fully-decoded AxlGfxBuffer; output is 4-channel BGRA matching AxlGfxPixel layout, so the returned buffer is directly blittable via axl_gfx_buffer_present.

Naming note: pixmap (map of pixels) — distinct from AxlImage — executable-image lifecycle (UEFI executable-image lifecycle).

API Reference

Image decoders for PNG, JPEG, GIF, and BMP into AxlGfxBuffer.

Decodes byte buffers into AxlGfxBuffer pixel arrays for blit-style consumption (icons, button bitmaps, CSS <img> and background- image). Backed by stb_image — public-domain single-header decoder vendored at deps/stb/stb_image.h.

Naming note: pixmap to distinguish from <axl/axl-image.h> (which is for UEFI executable-image lifecycle — LoadImage/StartImage/UnloadImage). pixmap

here is “map of

pixels” — the decoded raster data, not the format-on-disk and not anything executable.

Two entry points:

axl_pixmap_info returns dimensions WITHOUT decoding — useful for layout-driven container sizing before committing to a full pixel-buffer allocation.
axl_pixmap_decode returns a fully-decoded AxlGfxBuffer.

The public API is toolkit-neutral — no HTML/CSS-shaped intrinsic-sizing helpers, no DPI metadata. Consumers wrap at their own layer.

// Layout-before-decode: size the container, decide whether to
// commit to the full buffer alloc.
uint32_t w, h;
if (axl_pixmap_info(bytes, len, &w, &h) == AXL_OK
    && w <= my_max_w && h <= my_max_h)
{
    AxlGfxBuffer *buf = axl_pixmap_decode(bytes, len);
    if (buf) {
        axl_gfx_buffer_present(buf, dst_x, dst_y);
        axl_gfx_buffer_free(buf);
    }
}

Functions

int axl_pixmap_info(const uint8_t *bytes, size_t len, uint32_t *out_w, uint32_t *out_h)

Get pixel dimensions of an encoded image without allocating a decode buffer.

Wraps stb_image’s stbi_info_from_memory. Parses just enough of the format’s header to extract width and height — for PNG that’s the 8-byte signature + 25-byte IHDR chunk; for JPEG it’s the SOFn marker. Cheap compared to full decode.

Supports the same formats as axl_pixmap_decode (PNG, JPEG, GIF, BMP).

Parameters:

bytes – [in] encoded image byte buffer
len – buffer length in bytes
out_w – [out] image width in pixels (NULL OK)
out_h – [out] image height in pixels (NULL OK)

Returns:

AXL_OK on success. AXL_ERR if bytes is NULL, len is too small to contain any recognized format header, the format is unrecognized, or the header is malformed. Output pointers untouched on error.

AxlGfxBuffer *axl_pixmap_decode(const uint8_t *bytes, size_t len)

Decode an encoded image byte buffer into a fresh AxlGfxBuffer.

Format is auto-detected from the buffer magic; supports PNG, JPEG, GIF (first frame only), and BMP. Output is 4-channel BGRA matching AxlGfxPixel’s layout — directly blittable via axl_gfx_buffer_present. Source formats that omit alpha (e.g. opaque BMP, JPEG) get alpha = 0xFF for every pixel.

Decoded buffer dimensions match what axl_pixmap_info reports.

Callers receive ownership and must free with axl_gfx_buffer_free.

Parameters:

bytes – [in] encoded image byte buffer
len – buffer length in bytes

Returns:

new AxlGfxBuffer on success (caller frees). NULL on allocation failure, unrecognized format, malformed input, bytes NULL, or len 0.