one bit is equal to how many nibble
Nibble In computing, a nibble (occasionally nybble or nyble to match the spelling of byte) is a four-bit aggregation,[1][2] or half an octet. It is also known as half-byte[3] or tetrade.[4][5] In a networking or telecommunication context, the nibble is often called a semi-octet,[6] quadbit,[7] or quartet.[8][9] A nibble has sixteen (24) possible values. A nibble can be represented by a single hexadecimal digit and called a hex digit.[10]
Pixel The number of distinct colors that can be represented by a pixel depends on the number of bits per pixel (bpp). A 1 bpp image uses 1-bit for each pixel, so each pixel can be either on or off. Each additional bit doubles the number of colors available, so a 2 bpp image can have 4 colors, and a 3 bpp image can have 8 colors: