Struct TiffHeader 

pub struct TiffHeader {
    pub byte_order: ByteOrder,
    pub is_bigtiff: bool,
    pub first_ifd_offset: u64,
}

Parsed TIFF file header.

Contains the essential information needed to begin parsing IFDs:

• Byte order for reading all subsequent values
• Whether this is classic TIFF or BigTIFF (affects entry sizes and offset widths)
• Location of the first IFD

Fields

byte_order: ByteOrder

Byte order for all multi-byte values in the file

is_bigtiff: bool

Whether this is a BigTIFF file (64-bit offsets)

first_ifd_offset: u64

Offset to the first IFD in the file

Implementations

impl TiffHeader

pub fn parse(bytes: &[u8], file_size: u64) -> Result<Self, TiffError>

Parse a TIFF header from raw bytes.

The input must contain at least 8 bytes for classic TIFF or 16 bytes for BigTIFF. The function first reads enough to determine the format, then validates the rest.

Arguments

• bytes - Raw header bytes (at least 8 bytes, preferably 16 for BigTIFF support)
• file_size - Total file size (used to validate IFD offset)

Errors

• InvalidMagic if byte order bytes are not II or MM
• InvalidVersion if version is not 42 or 43
• InvalidBigTiffOffsetSize if BigTIFF offset size is not 8
• FileTooSmall if there aren’t enough bytes for the header
• InvalidIfdOffset if the first IFD offset is outside the file

pub const fn ifd_entry_size(&self) -> usize

Size of an IFD entry in bytes.

Classic TIFF: 12 bytes (2 tag + 2 type + 4 count + 4 value/offset) BigTIFF: 20 bytes (2 tag + 2 type + 8 count + 8 value/offset)

pub const fn ifd_count_size(&self) -> usize

Size of the entry count field at the start of an IFD.

Classic TIFF: 2 bytes (u16) BigTIFF: 8 bytes (u64)

pub const fn ifd_next_offset_size(&self) -> usize

Size of the next IFD offset field at the end of an IFD.

Classic TIFF: 4 bytes (u32) BigTIFF: 8 bytes (u64)

pub const fn value_offset_size(&self) -> usize

Size of the value/offset field in an IFD entry.

This determines the inline value threshold: Classic TIFF: 4 bytes BigTIFF: 8 bytes

Trait Implementations

impl Clone for TiffHeader

fn clone(&self) -> TiffHeader

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TiffHeader

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

Formats the value using the given formatter.

impl PartialEq for TiffHeader

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

Tests for self and other values to be equal, and is used by ==.

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

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

impl Copy for TiffHeader

impl Eq for TiffHeader

impl StructuralPartialEq for TiffHeader