ARGB

ARGB stands for Alpha, Red, Green, and Blue. It is a color model and pixel format used in digital imaging and computer graphics that includes an alpha channel for transparency in addition to the three color channels. In common implementations, each channel is 8 bits, yielding a 32-bit value per pixel. A typical hexadecimal form is 0xAARRGGBB, where A is alpha, R is red, G is green, and B is blue; however, the exact byte order in memory depends on endianness and API, leading to variations such as ARGB, RGBA, BGRA, or ABGR in different systems.

The alpha component encodes transparency: 0 means fully transparent, 255 fully opaque. In compositing, the alpha value determines how a pixel blends with the background. Some frameworks use pre-multiplied alpha, where the color channels are already scaled by alpha to simplify blending; others use straight (unassociated) alpha, requiring a separate multiplication step during compositing.

ARGB is widely used for image buffers, textures, and framebuffer formats in graphics pipelines and user interface toolkits. Image formats and APIs often choose a particular channel order, so converting between formats may involve reordering or changing alpha handling. For example, many platforms expose colors as 32-bit integers in the form AARRGGBB, but memory order can differ depending on platform and driver.

In practice, ARGB is a general representation rather than a single file format; it underpins many pixel formats and color models used by graphics software, game engines, and operating systems.