Crop source slice length does not match destination slice length about fast_image_resize HOT 3 CLOSED

seddonm1 commented on May 26, 2024

Crop source slice length does not match destination slice length

from fast_image_resize.

Comments (3)

Cykooz commented on May 26, 2024

I have been trying to do a crop of a 640x480 image to a 640x640 image

You can't crop into size bigger than size of source image.
If you want to store resizing result into some region of destination image, you must:

create a big destination image (640x640);
get DynamicImageViewMut from it;
crop this view into smaller (640x480) DynamicImageViewMut;
use cropped DynamicImageViewMut as dst_image parameter for Resizer::resize() function.

from fast_image_resize.

seddonm1 commented on May 26, 2024

Hi @Cykooz .

Sorry I was not very clear in my initial message. Here is some code to reproduce the issue:

use fast_image_resize::{CropBox, Image, PixelType, ResizeAlg, Resizer};
use std::num::NonZeroU32;

fn main() {
    let source_image = Image::new(
        NonZeroU32::new(640).unwrap(),
        NonZeroU32::new(480).unwrap(),
        PixelType::U8x3,
    );

    // Create container for data of destination image. Initialised as RGB (0,0,0)
    let mut target_image = Image::new(
        NonZeroU32::new(640).unwrap(),
        NonZeroU32::new(640).unwrap(),
        PixelType::U8x3,
    );

    // Get mutable view of destination image data
    let mut dst_view = target_image
        .view_mut()
        .crop(CropBox {
            left: 0,
            top: 80,
            width: NonZeroU32::new(640).unwrap(),
            height: NonZeroU32::new(480).unwrap(),
        })
        .unwrap();

    // do the resize
    Resizer::new(ResizeAlg::Nearest)
        .resize(&source_image.view(), &mut dst_view)
        .unwrap();
}