# [−][src]Struct image::pnm::PNMHeader

    pub struct PNMHeader { /* fields omitted */ }

Stores the complete header data of a file.

Internally, provides mechanisms for lossless reencoding. After reading a file with the decoder it is possible to recover the header and construct an encoder. Using the encoder on the just loaded image should result in a byte copy of the original file (for single image pnms without additional trailing data).

## Methods

### `impl PNMHeader`[src]

#### `pub fn subtype(&self) -> PNMSubtype`[src]

Retrieve the format subtype from which the header was created.

#### `pub fn width(&self) -> u32`[src]

The width of the image this header is for.

#### `pub fn height(&self) -> u32`[src]

The height of the image this header is for.

#### `pub fn maximal_sample(&self) -> u32`[src]

The biggest value a sample can have. In other words, the colour resolution.

#### `pub fn as_bitmap(&self) -> Option<&BitmapHeader>`[src]

Retrieve the underlying bitmap header if any

#### `pub fn as_graymap(&self) -> Option<&GraymapHeader>`[src]

Retrieve the underlying graymap header if any

#### `pub fn as_pixmap(&self) -> Option<&PixmapHeader>`[src]

Retrieve the underlying pixmap header if any

#### `pub fn as_arbitrary(&self) -> Option<&ArbitraryHeader>`[src]

Retrieve the underlying arbitrary header if any

#### `pub fn write(&self, writer: &mut dyn Write) -> Result<()>`[src]

Write the header back into a binary stream

## Trait Implementations

### `impl From<BitmapHeader> for PNMHeader`[src]

#### `fn from(header: BitmapHeader) -> Self`[src]

Performs the conversion.

### `impl From<GraymapHeader> for PNMHeader`[src]

#### `fn from(header: GraymapHeader) -> Self`[src]

Performs the conversion.

### `impl From<PixmapHeader> for PNMHeader`[src]

#### `fn from(header: PixmapHeader) -> Self`[src]

Performs the conversion.

### `impl From<ArbitraryHeader> for PNMHeader`[src]

#### `fn from(header: ArbitraryHeader) -> Self`[src]

Performs the conversion.

## Auto Trait Implementations

### `impl Send for PNMHeader`

### `impl Unpin for PNMHeader`

### `impl Sync for PNMHeader`

### `impl UnwindSafe for PNMHeader`

### `impl RefUnwindSafe for PNMHeader`

## Blanket Implementations

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `fn into(self) -> U`[src]

Performs the conversion.

### `impl<T> From<T> for T`[src]

#### `fn from(t: T) -> T`[src]

Performs the conversion.

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

#### `type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

#### `fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `fn borrow_mut(&mut self) -> &mut T`[src]

Mutably borrows from an owned value. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `fn borrow(&self) -> &T`[src]

Immutably borrows from an owned value. Read more

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> SetParameter for T`[src]

#### `fn set<T>(&mut self, value: T) -> <T as Parameter<Self>>::Result where
T: Parameter<Self>,` [src]

Sets `value` as a parameter of `self`.

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