Struct qoi::Header

pub struct Header {
    pub width: u32,
    pub height: u32,
    pub channels: Channels,
    pub colorspace: ColorSpace,
}

Image header: dimensions, channels, color space.

Notes

A valid image header must satisfy the following conditions:

• Both width and height must be non-zero.
• Maximum number of pixels is 400Mp (=4e8 pixels).

Fields

width: u32

Image width in pixels

height: u32

Image height in pixels

channels: Channels

Number of 8-bit channels per pixel

colorspace: ColorSpace

Color space (informative field, doesn’t affect encoding)

Implementations

impl Header

pub const fn try_new( width: u32, height: u32, channels: Channels, colorspace: ColorSpace, ) -> Result<Self>

Creates a new header and validates image dimensions.

pub const fn with_channels(self, channels: Channels) -> Self

Creates a new header with modified channels.

pub const fn with_colorspace(self, colorspace: ColorSpace) -> Self

Creates a new header with modified color space.

pub(crate) fn encode(&self) -> [u8; 14]

Serializes the header into a bytes array.

pub(crate) fn decode(data: impl AsRef<[u8]>) -> Result<Self>

Deserializes the header from a byte array.

pub const fn n_pixels(&self) -> usize

Returns a number of pixels in the image.

pub const fn n_bytes(&self) -> usize

Returns the total number of bytes in the raw pixel array.

This may come useful when pre-allocating a buffer to decode the image into.

pub fn encode_max_len(&self) -> usize

The maximum number of bytes the encoded image will take.

Can be used to pre-allocate the buffer to encode the image into.

Trait Implementations

impl Clone for Header

fn clone(&self) -> Header

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Header

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Header

fn default() -> Self

Returns the “default value” for a type.

impl Hash for Header

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Header

fn eq(&self, other: &Header) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Header

impl Eq for Header

impl StructuralPartialEq for Header