Struct OCRResize 

pub struct OCRResize {
    pub rec_image_shape: [usize; 3],
    pub input_shape: Option<[usize; 3]>,
    pub max_img_w: usize,
}

OCR-specific image resizer.

This struct handles resizing of images for OCR processing. It supports both dynamic resizing based on the image’s width-to-height ratio and static resizing to fixed dimensions.

Fields

rec_image_shape: [usize; 3]

input_shape: Option<[usize; 3]>

max_img_w: usize

Implementations

impl OCRResize

pub fn new( rec_image_shape: Option<[usize; 3]>, input_shape: Option<[usize; 3]>, ) -> Self

Creates a new OCRResize instance with default maximum width.

Arguments

• rec_image_shape - Optional shape for recognition images [channels, height, width]. If None, uses DEFAULT_REC_IMAGE_SHAPE.
• input_shape - Optional input shape [channels, height, width].

Returns

A new OCRResize instance.

pub fn with_max_width( rec_image_shape: Option<[usize; 3]>, input_shape: Option<[usize; 3]>, max_img_w: Option<usize>, ) -> Self

Creates a new OCRResize instance with custom maximum width.

Arguments

• rec_image_shape - Optional shape for recognition images [channels, height, width]. If None, uses DEFAULT_REC_IMAGE_SHAPE.
• input_shape - Optional input shape [channels, height, width].
• max_img_w - Optional maximum image width. If None, uses DEFAULT_MAX_IMG_WIDTH.

Returns

A new OCRResize instance.

pub fn resize_img(&self, img: &RgbImage, max_wh_ratio: f32) -> RgbImage

Resizes an image based on a maximum width-to-height ratio.

This method resizes an image to fit within the specified dimensions while maintaining the aspect ratio. If the calculated width exceeds the maximum allowed width, the image is resized to the maximum width.

Arguments

• img - The input RGB image to resize.
• max_wh_ratio - The maximum width-to-height ratio for the resized image.

Returns

A resized and padded RGB image.

pub fn resize(&self, img: &RgbImage) -> RgbImage

Resizes an image using the default width-to-height ratio from rec_image_shape.

This method calculates the width-to-height ratio from the configured rec_image_shape and uses it to resize the image via resize_img.

Arguments

• img - The input RGB image to resize.

Returns

A resized and padded RGB image.

pub fn static_resize(&self, img: &RgbImage) -> Result<RgbImage, OCRError>

Resizes an image to a static size defined by input_shape.

This method resizes an image to exact dimensions specified in the input_shape. It requires input_shape to be configured, otherwise it returns a ConfigError.

Arguments

• img - The input RGB image to resize.

Returns

A resized RGB image or an OCRError if input_shape is not configured.

pub fn apply(&self, imgs: &[RgbImage]) -> Result<Vec<RgbImage>, OCRError>

Applies resizing to a batch of images.

This method applies either dynamic resizing (using resize) or static resizing (using static_resize) to a batch of images, depending on whether input_shape is configured. If input_shape is None, dynamic resizing is used; otherwise, static resizing is used.

Arguments

• imgs - A slice of RGB images to resize.

Returns

A vector of resized RGB images or an OCRError if static resizing fails.

pub fn resize_to_tensor_shape( &self, img: &RgbImage, ) -> Result<RgbImage, OCRError>

Resizes an image to fit tensor shape requirements.

This method resizes an image to fit within the dimensions specified by rec_image_shape, while maintaining the aspect ratio. If the calculated width exceeds the maximum allowed width, the image is resized to the maximum width. The resulting image is padded to match the target dimensions.

Arguments

• img - The input RGB image to resize.

Returns

A resized and padded RGB image or an OCRError.

pub fn apply_to_images( &self, imgs: &[RgbImage], ) -> Result<Vec<RgbImage>, OCRError>

Applies tensor shape resizing to a batch of images.

This method applies resize_to_tensor_shape to a batch of images. It handles empty batches by returning an empty vector.

Arguments

• imgs - A slice of RGB images to resize.

Returns

A vector of resized RGB images or an OCRError if resizing fails.

Trait Implementations

impl Debug for OCRResize

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

Formats the value using the given formatter.