Struct PngTextChunks 

pub struct PngTextChunks { /* private fields */ }

PNG tEXt chunks, decoded as Latin-1 (key, value) pairs in file order.

Duplicate keys are preserved (PNG spec permits multiple tEXt chunks with the same keyword). Encoding is strict Latin-1 per spec — no UTF-8 sniffing.

Note: when a PNG carries EXIF inside a Raw profile type exif / Raw profile type APP1 text chunk (legacy ImageMagick / Photoshop pattern), the EXIF entries are merged into the Exif (under ImageMetadata.exif) transparently; the original text chunk is also visible here.

Forward-compatible: future iTXt / zTXt support can extend PngTextChunks non-breakingly.

Implementations

impl PngTextChunks

pub fn get(&self, key: &str) -> Option<&str>

First value whose key matches exactly, or None.

pub fn get_all<'a>(&'a self, key: &'a str) -> impl Iterator<Item = &'a str> + 'a

All values whose key matches exactly, in file order.

pub fn iter(&self) -> impl Iterator<Item = (&str, &str)> + '_

All (key, value) pairs in file order, including duplicates.

pub fn len(&self) -> usize

Number of (key, value) pairs (counts duplicates).

pub fn is_empty(&self) -> bool

true if no tEXt entries are present.

Trait Implementations

impl Clone for PngTextChunks

fn clone(&self) -> PngTextChunks

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PngTextChunks

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

Formats the value using the given formatter.

impl Default for PngTextChunks

fn default() -> PngTextChunks

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for PngTextChunks

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for PngTextChunks

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.