Enum LayoutElementType 

pub enum LayoutElementType {
    DocTitle,
    ParagraphTitle,
    Text,
    Content,
    Abstract,
    Image,
    Table,
    Chart,
    Formula,
    FigureTitle,
    TableTitle,
    ChartTitle,
    FigureTableChartTitle,
    Header,
    HeaderImage,
    Footer,
    FooterImage,
    Footnote,
    Seal,
    Number,
    Reference,
    ReferenceContent,
    Algorithm,
    FormulaNumber,
    AsideText,
    List,
    Region,
    Other,
}

Layout element type supporting PP-StructureV3’s full label set.

This enum represents both semantic categories and fine-grained labels for layout elements. PP-StructureV3 models output 20 or 23 class labels depending on the model variant.

The original model-specific label is preserved in LayoutElement.label field.

PP-StructureV3 Label Categories

Document structure:

• DocTitle - Document title (doc_title)
• ParagraphTitle - Section/paragraph title (paragraph_title)
• Text - General text content
• Content - Table of contents (content)
• Abstract - Abstract section

Visual elements:

• Image - Images/figures (image, figure)
• Table - Tables
• Chart - Charts/graphs
• Formula - Mathematical formulas

Captions and titles:

• FigureTitle - Figure caption (figure_title)
• TableTitle - Table caption (table_title)
• ChartTitle - Chart caption (chart_title)
• FigureTableChartTitle - Combined caption type

Page structure:

• Header - Page header
• HeaderImage - Header image
• Footer - Page footer
• FooterImage - Footer image
• Footnote - Footnotes

Special elements:

• Seal - Stamps/official seals

• Number - Page numbers

• Reference - References section

• ReferenceContent - Reference content

• Algorithm - Algorithm blocks

• FormulaNumber - Formula numbers

• AsideText - Marginal/aside text

• List - List items

• Other - Unknown/unmapped labels

Variants

DocTitle

Document title

ParagraphTitle

Paragraph/section title

Text

General text content

Content

Table of contents

Abstract

Abstract section

Image

Image or figure

Table

Table

Chart

Chart or graph

Formula

Mathematical formula

FigureTitle

Figure caption/title

TableTitle

Table caption/title

ChartTitle

Chart caption/title

FigureTableChartTitle

Combined figure/table/chart title (PP-DocLayout)

Header

Page header

HeaderImage

Header image

Footer

Page footer

FooterImage

Footer image

Footnote

Footnote

Seal

Stamp or official seal

Number

Page number

Reference

Reference section

ReferenceContent

Reference content (PP-DocLayout_plus-L)

Algorithm

Algorithm block

FormulaNumber

Formula number

AsideText

Marginal/aside text

List

List items

Region

Generic document region block (PP-DocBlockLayout) Used for hierarchical layout ordering and block grouping

Other

Other/unknown (original label preserved in LayoutElement.label)

Implementations

impl LayoutElementType

pub fn as_str(&self) -> &'static str

Returns the string representation of the element type.

This returns the PP-StructureV3 compatible label string.

pub fn from_label(label: &str) -> LayoutElementType

Creates a LayoutElementType from a string label with fine-grained mapping.

This method maps model output labels to their corresponding fine-grained types, preserving the full PP-StructureV3 label set (20/23 classes).

pub fn semantic_category(&self) -> &'static str

Returns the semantic category for this element type.

This method groups fine-grained types into broader semantic categories, useful for processing logic that doesn’t need fine-grained distinctions.

Categories

• Title: DocTitle, ParagraphTitle
• Text: Text, Content, Abstract
• Visual: Image, Chart
• Table: Table
• Caption: FigureTitle, TableTitle, ChartTitle, FigureTableChartTitle
• Header: Header, HeaderImage
• Footer: Footer, FooterImage, Footnote
• Formula: Formula, FormulaNumber
• Special: Seal, Number, Reference, ReferenceContent, Algorithm, AsideText
• List: List
• Other: Other

pub fn is_title(&self) -> bool

Returns whether this element type is a title variant.

pub fn is_visual(&self) -> bool

Returns whether this element type is a visual element (image, chart, figure).

pub fn is_caption(&self) -> bool

Returns whether this element type is a caption variant.

pub fn is_header(&self) -> bool

Returns whether this element type is a header variant.

pub fn is_footer(&self) -> bool

Returns whether this element type is a footer variant.

pub fn is_formula(&self) -> bool

Returns whether this element type is a formula variant.

pub fn should_ocr(&self) -> bool

Returns whether this element type contains text content that should be OCR’d.

Trait Implementations

impl Clone for LayoutElementType

fn clone(&self) -> LayoutElementType

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LayoutElementType

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for LayoutElementType

fn deserialize<__D>( __deserializer: __D, ) -> Result<LayoutElementType, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for LayoutElementType

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

where __H: Hasher,

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 LayoutElementType

fn eq(&self, other: &LayoutElementType) -> 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 Serialize for LayoutElementType

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Copy for LayoutElementType

impl Eq for LayoutElementType

impl StructuralPartialEq for LayoutElementType