Struct Scanner 

pub struct Scanner { /* private fields */ }

Available on crate feature scan only.

Reads barcodes out of images.

Examples

use smart_package_tracker::scan::{GrayImage, Scanner};

let image = GrayImage::from_luma(width, 40, luma)?;
let found = Scanner::new().scan(&image)?;

assert_eq!(found.payload(), "PKG-9ED9285C");

Implementations

impl Scanner

pub fn new() -> Self

A scanner with default settings.

pub fn max_scan_lines(self, lines: u32) -> Self

How many scan lines to try along each axis.

Raising this helps when the barcode occupies a small part of a large image; lowering it bounds the work done before giving up. Zero is treated as one.

pub fn scan(&self, image: &GrayImage) -> Result<Scan>

Read any barcode this crate can decode out of image.

Code 128 is currently the only symbology this crate can decode, so this is a shorthand for scan_with. It stays a separate method because it is where any future symbology gets tried without callers changing.

Errors

Returns Error::NoSymbolFound if no scan line yields a valid symbol. A barcode that is present but unreadable is indistinguishable from one that is absent, so there is only the one error.

pub fn scan_with<D: Decoder + ?Sized>( &self, decoder: &D, image: &GrayImage, ) -> Result<Scan>

Read a barcode of one specific symbology out of image.

Errors

Returns Error::NoSymbolFound if no scan line yields a valid symbol, or Error::Decode if the symbology has no scan-line structure — matrix symbologies such as QR cannot be read this way.

Trait Implementations

impl Clone for Scanner

fn clone(&self) -> Scanner

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Scanner

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

Formats the value using the given formatter.

impl Default for Scanner

fn default() -> Self

Returns the “default value” for a type.

impl Eq for Scanner

impl PartialEq for Scanner

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Scanner