Struct Header

impl Header

fn new(name: Text, data_size: impl Into<Vec2<usize>>, channels: SmallVec<[ChannelDescription; 5]>) -> Self

Create a new Header with the specified name, display window and channels. Use Header::with_encoding and the similar methods to add further properties to the header.

The other settings are left to their default values:

• RLE compression
• display window equal to data window
• tiles (64 x 64 px)
• unspecified line order
• no custom attributes

const fn with_display_window(self, display_window: IntegerBounds) -> Self

Set the display window, that is, the global clipping rectangle. Must be the same for all headers of a file.

const fn with_position(self, position: Vec2<i32>) -> Self

Set the offset of this layer.

fn with_encoding(self, compression: Compression, blocks: BlockDescription, line_order: LineOrder) -> Self

Set compression, tiling, and line order. Automatically computes chunk count.

fn with_attributes(self, own_attributes: LayerAttributes) -> Self

Set all attributes of the header that are not shared with all other headers in the image.

fn with_shared_attributes(self, shared_attributes: ImageAttributes) -> Self

Set all attributes of the header that are shared with all other headers in the image.

fn enumerate_ordered_blocks(&self) -> impl Iterator<Item = (usize, TileIndices)> + Send

Iterate over all blocks, in the order specified by the headers line order attribute. Unspecified line order is treated as increasing line order. Also enumerates the index of each block in the header, as if it were sorted in increasing line order.

fn blocks_increasing_y_order(&self) -> impl ExactSizeIterator<Item = TileIndices> + DoubleEndedIterator

Iterate over all tile indices in this header in LineOrder::Increasing order.

const fn max_block_pixel_size(&self) -> Vec2<usize>

The default pixel resolution of a single block (tile or scan line block). Not all blocks have this size, because they may be cutoff at the end of the image.

fn get_block_data_window_pixel_coordinates(&self, tile: TileCoordinates) -> Result<IntegerBounds>

Calculate the position of a block in the global infinite 2D space of a file. May be negative.

fn get_absolute_block_pixel_coordinates(&self, tile: TileCoordinates) -> Result<IntegerBounds>

Calculate the pixel index rectangle inside this header. Is not negative. Starts at 0.

fn get_block_data_indices(&self, block: &CompressedBlock) -> Result<TileCoordinates>

Return the tile index, converting scan line block coordinates to tile indices. Starts at 0 and is not negative.

fn get_scan_line_block_tile_coordinates(&self, block_y_coordinate: i32) -> Result<TileCoordinates>

Computes the absolute tile coordinate data indices, which start at 0.

fn max_block_byte_size(&self) -> usize

Maximum byte length of an uncompressed or compressed block, used for validation.

fn total_pixel_bytes(&self) -> usize

Returns the number of bytes that the pixels of this header will require when stored without compression. Respects multi-resolution levels and subsampling.

fn max_pixel_file_bytes(&self) -> usize

Approximates the maximum number of bytes that the pixels of this header will consume in a file. Due to compression, the actual byte size may be smaller.

fn validate(&self, is_multilayer: bool, long_names: &mut bool, strict: bool) -> UnitResult

Validate this instance.

fn read_all(read: &mut PeekRead<impl Read>, version: &Requirements, pedantic: bool) -> Result<Headers>

Read the headers without validating them.

fn write_all(headers: &[Self], write: &mut impl Write, is_multilayer: bool) -> UnitResult

Without validation, write the headers to the byte stream.

fn all_named_attributes(&self) -> impl '_ + Iterator<Item = (&TextSlice, AttributeValue)>

Iterate over all (name, attribute_value) pairs in this header that would be written to a file. The order of attributes is arbitrary and may change in future versions. Will always contain all strictly required attributes, such as channels, compression, data window, and similar. Hint: Use attribute.kind_name() to obtain the standardized name of the attribute type. Does not validate the header or attributes.

fn read(read: &mut PeekRead<impl Read>, requirements: &Requirements, pedantic: bool) -> Result<Self>

Read the value without validating.

fn write(&self, write: &mut impl Write) -> UnitResult

Without validation, write this instance to the byte stream.

fn data_window(&self) -> IntegerBounds

The rectangle describing the bounding box of this layer within the infinite global 2D space of the file.