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//! In graphics code it's very common to pass `width` and `height` along with a `Vec` of pixels,
//! all as separate arguments. This is tedious, and can lead to errors.
//!
//! This crate is a simple struct that adds dimensions to the underlying buffer. This makes it easier to correctly keep track
//! of the image size and allows passing images with just one function argument instead three or four.
//!
//! Additionally, it has a concept of a `stride`, which allows defining sub-regions of images without copying,
//! as well as handling padding (e.g. buffers for video frames may require to be a multiple of 8, regardless of logical image size).
//!
//! For convenience, there are iterators over rows or all pixels of a (sub)image and
//! pixel-based indexing directly with `img[(x,y)]` (where `x`/`y` can be `u32` as well as `usize`).
//!
//! `Img<Container>` type has aliases for common uses:
//!
//! * Owned: `ImgVec<T>` → `Img<Vec<T>>` (use it in `struct`s and return types)
//! * Reference: `ImgRef<T>` → `Img<&[T]>` (use it in function arguments)
//! * Mutable reference: `ImgRefMut<T>` → `Img<&mut [T]>`
//!
//! It is assumed that the container is [one element per pixel](https://crates.io/crates/rgb/), e.g. `Vec<RGBA>`,
//! and _not_ a `Vec<u8>` where 4 `u8` elements are interpreted as one pixel.
//!
//!
//! ```rust
//! use imgref::*;
//! # fn some_image_processing_function(img: ImgRef<u8>) -> ImgVec<u8> { img.new_buf(img.buf().to_vec()) }
//!
//! fn main() {
//! let img = Img::new(vec![0; 1000], 50, 20); // 1000 pixels of a 50×20 image
//!
//! let new_image = some_image_processing_function(img.as_ref()); // Use imgvec.as_ref() instead of &imgvec for better efficiency
//!
//! println!("New size is {}×{}", new_image.width(), new_image.height());
//! println!("And the top left pixel is {:?}", new_image[(0u32,0u32)]);
//!
//! let first_row_slice = &new_image[0];
//!
//! for row in new_image.rows() {
//! // …
//! }
//! for px in new_image.pixels() {
//! // …
//! }
//!
//! // slice (x, y, width, height) by reference - no copy!
//! let fragment = img.sub_image(5, 5, 15, 15);
//!
//! //
//! let (vec, width, height) = fragment.to_contiguous_buf();
//! }
//! ```
#![no_std]
extern crate alloc;
#[cfg(test)]
extern crate std;
use alloc::borrow::{Cow, ToOwned};
use alloc::vec::Vec;
use core::slice;
mod traits;
mod ops;
mod iter;
pub use iter::*;
/// Image owning its pixels.
///
/// A 2D array of pixels. The pixels are oriented top-left first and rows are `stride` pixels wide.
///
/// If size of the `buf` is larger than `width`*`height`, then any excess space is a padding (see `width_padded()`/`height_padded()`).
pub type ImgVec<Pixel> = Img<Vec<Pixel>>;
/// Reference to pixels inside another image.
/// Pass this structure by value (i.e. `ImgRef`, not `&ImgRef`).
///
/// Only `width` of pixels of every `stride` can be modified. The `buf` may be longer than `height`*`stride`, but the extra space should be ignored.
pub type ImgRef<'a, Pixel> = Img<&'a [Pixel]>;
/// Same as `ImgRef`, but mutable
/// Pass this structure by value (i.e. `ImgRef`, not `&ImgRef`).
///
pub type ImgRefMut<'a, Pixel> = Img<&'a mut [Pixel]>;
/// Additional methods that depend on buffer size
///
/// To use these methods you need:
///
/// ```rust
/// use imgref::*;
/// ```
pub trait ImgExt<Pixel> {
/// Maximum possible width of the data, including the stride.
///
/// # Panics
///
/// This method may panic if the underlying buffer is not at least `height()*stride()` pixels large.
#[cfg(feature = "deprecated")]
fn width_padded(&self) -> usize;
/// Height in number of full strides.
/// If the underlying buffer is not an even multiple of strides, the last row is ignored.
///
/// # Panics
///
/// This method may panic if the underlying buffer is not at least `height()*stride()` pixels large.
#[cfg(feature = "deprecated")]
fn height_padded(&self) -> usize;
/// Iterate over the entire buffer as rows, including all padding
///
/// Rows will have up to `stride` width, but the last row may be shorter.
#[cfg(feature = "deprecated")]
fn rows_padded(&self) -> slice::Chunks<'_, Pixel>;
/// Borrow the container
fn as_ref(&self) -> ImgRef<Pixel>;
}
/// Additional methods that depend on buffer size
///
/// To use these methods you need:
///
/// ```rust
/// use imgref::*;
/// ```
pub trait ImgExtMut<Pixel> {
/// Iterate over the entire buffer as rows, including all padding
///
/// Rows will have up to `stride` width, but the last row may be shorter.
#[cfg(feature = "deprecated")]
fn rows_padded_mut(&mut self) -> slice::ChunksMut<'_, Pixel>;
/// Borrow the container mutably
fn as_mut(&mut self) -> ImgRefMut<Pixel>;
}
/// Basic struct used for both owned (alias `ImgVec`) and borrowed (alias `ImgRef`) image fragments.
///
/// Note: the fields are `pub` only because of borrow checker limitations. Please consider them as read-only.
#[derive(Debug, Copy, Clone)]
pub struct Img<Container> {
/// Storage for the pixels. Usually `Vec<Pixel>` or `&[Pixel]`. See `ImgVec` and `ImgRef`.
///
/// Note that future version will make this field private. Use `.rows()` and `.pixels()` iterators where possible, or `buf()`/`buf_mut()`/`into_buf()`.
#[deprecated(note = "Don't access struct fields directly. Use buf(), buf_mut() or into_buf()")]
#[cfg(feature = "deprecated")]
pub buf: Container,
#[cfg(not(feature = "deprecated"))]
buf: Container,
/// Number of pixels to skip in the container to advance to the next row.
///
/// Note: pixels between `width` and `stride` may not be usable, and may not even exist in the last row.
#[deprecated(note = "Don't access struct fields directly. Use stride()")]
#[cfg(feature = "deprecated")]
pub stride: usize,
#[cfg(not(feature = "deprecated"))]
stride: usize,
/// Width of the image in pixels.
///
/// Note that this isn't same as the width of the row in the `buf`, see `stride`
#[deprecated(note = "Don't access struct fields directly. Use width()")]
#[cfg(feature = "deprecated")]
pub width: u32,
#[cfg(not(feature = "deprecated"))]
width: u32,
/// Height of the image in pixels.
#[deprecated(note = "Don't access struct fields directly. Use height()")]
#[cfg(feature = "deprecated")]
pub height: u32,
#[cfg(not(feature = "deprecated"))]
height: u32,
}
impl<Container> Img<Container> {
/// Width of the image in pixels.
///
/// Note that this isn't same as the width of the row in image data, see `stride()`
#[inline(always)]
#[allow(deprecated)]
pub fn width(&self) -> usize {self.width as usize}
/// Height of the image in pixels.
#[inline(always)]
#[allow(deprecated)]
pub fn height(&self) -> usize {self.height as usize}
/// Number of _pixels_ to skip in the container to advance to the next row.
///
/// Note the last row may have fewer pixels than the stride.
/// Some APIs use number of *bytes* for a stride. You may need to multiply this one by number of pixels.
#[inline(always)]
#[allow(deprecated)]
pub fn stride(&self) -> usize {self.stride}
/// Immutable reference to the pixel storage. Warning: exposes stride. Use `pixels()` or `rows()` instead.
///
/// See also `into_contiguous_buf()`.
#[inline(always)]
#[allow(deprecated)]
pub fn buf(&self) -> &Container {&self.buf}
/// Mutable reference to the pixel storage. Warning: exposes stride. Use `pixels_mut()` or `rows_mut()` instead.
///
/// See also `into_contiguous_buf()`.
#[inline(always)]
#[allow(deprecated)]
pub fn buf_mut(&mut self) -> &mut Container {&mut self.buf}
/// Get the pixel storage by consuming the image. Be careful about stride — see `into_contiguous_buf()` for a safe version.
#[inline(always)]
#[allow(deprecated)]
pub fn into_buf(self) -> Container {self.buf}
#[deprecated(note = "this was meant to be private, use new_buf() and/or rows()")]
#[cfg(feature = "deprecated")]
#[doc(hidden)]
pub fn rows_buf<'a, T: 'a>(&self, buf: &'a [T]) -> RowsIter<'a, T> {
self.rows_buf_internal(buf)
}
#[inline]
#[track_caller]
fn rows_buf_internal<'a, T: 'a>(&self, buf: &'a [T]) -> RowsIter<'a, T> {
let stride = self.stride();
debug_assert!(self.width() <= self.stride());
debug_assert!(buf.len() >= self.width() * self.height());
assert!(stride > 0);
let non_padded = &buf[0..stride * self.height() + self.width() - stride];
RowsIter {
width: self.width(),
inner: non_padded.chunks(stride),
}
}
}
impl<Pixel,Container> ImgExt<Pixel> for Img<Container> where Container: AsRef<[Pixel]> {
#[inline(always)]
#[cfg(feature = "deprecated")]
fn width_padded(&self) -> usize {
self.stride()
}
#[inline(always)]
#[cfg(feature = "deprecated")]
fn height_padded(&self) -> usize {
let len = self.buf().as_ref().len();
assert_eq!(0, len % self.stride());
len / self.stride()
}
/// Iterate over the entire buffer as rows, including all padding
///
/// Rows will have up to `stride` width, but the last row may be shorter.
#[inline(always)]
#[cfg(feature = "deprecated")]
fn rows_padded(&self) -> slice::Chunks<'_, Pixel> {
self.buf().as_ref().chunks(self.stride())
}
#[inline(always)]
#[allow(deprecated)]
fn as_ref(&self) -> ImgRef<Pixel> {
Img {
buf: self.buf.as_ref(),
width: self.width,
height: self.height,
stride: self.stride,
}
}
}
impl<Pixel,Container> ImgExtMut<Pixel> for Img<Container> where Container: AsMut<[Pixel]> {
/// Iterate over the entire buffer as rows, including all padding
///
/// Rows will have up to `stride` width, but the last row may be shorter.
///
/// # Panics
///
/// If stride is 0
#[inline]
#[must_use]
#[cfg(feature = "deprecated")]
fn rows_padded_mut(&mut self) -> slice::ChunksMut<'_, Pixel> {
let stride = self.stride();
self.buf_mut().as_mut().chunks_mut(stride)
}
#[inline(always)]
#[allow(deprecated)]
fn as_mut(&mut self) -> ImgRefMut<Pixel> {
Img {
buf: self.buf.as_mut(),
width: self.width,
height: self.height,
stride: self.stride,
}
}
}
#[inline]
fn sub_image(left: usize, top: usize, width: usize, height: usize, stride: usize, buf_len: usize) -> (usize, usize, usize) {
let start = stride * top + left;
let full_strides_end = start + stride * height;
// when left > 0 and height is full, the last line is shorter than the stride
let end = if buf_len >= full_strides_end {
full_strides_end
} else {
debug_assert!(height > 0);
let min_strides_len = full_strides_end + width - stride;
debug_assert!(buf_len >= min_strides_len, "the buffer is too small to fit the subimage");
// if can't use full buffer, then shrink to min required (last line having exact width)
min_strides_len
};
(start, end, stride)
}
impl<'a, T> ImgRef<'a, T> {
/// Make a reference for a part of the image, without copying any pixels.
///
/// # Panics
///
/// It will panic if sub_image is outside of the image area
/// (left + width must be <= container width, etc.)
#[inline]
#[must_use]
#[track_caller]
pub fn sub_image(&self, left: usize, top: usize, width: usize, height: usize) -> Self {
assert!(top + height <= self.height());
assert!(left + width <= self.width());
let (start, end, stride) = sub_image(left, top, width, height, self.stride(), self.buf().len());
let buf = &self.buf()[start..end];
Self::new_stride(buf, width, height, stride)
}
#[inline]
/// Iterate over whole rows of pixels as slices
///
/// # Panics
///
/// If stride is 0
///
/// See also `pixels()`
pub fn rows(&self) -> RowsIter<'_, T> {
self.rows_buf_internal(self.buf())
}
/// Deprecated
///
/// Note: it iterates **all** pixels in the underlying buffer, not just limited by width/height.
#[deprecated(note = "Size of this buffer is unpredictable. Use .rows() instead")]
#[cfg(feature = "deprecated")]
#[doc(hidden)]
pub fn iter(&self) -> slice::Iter<'_, T> {
self.buf().iter()
}
}
impl<'a, T: Clone> ImgRef<'a, T> {
/// Returns a reference to the buffer, width, height. Guarantees that the buffer is contiguous,
/// i.e. it's `width*height` elements long, and `[x + y*width]` addresses each pixel.
///
/// It will create a copy if the buffer isn't contiguous (width != stride).
/// For a more efficient version, see `into_contiguous_buf()`
#[allow(deprecated)]
#[must_use]
pub fn to_contiguous_buf(&self) -> (Cow<'a, [T]>, usize, usize) {
let width = self.width();
let height = self.height();
let stride = self.stride();
if width == stride {
return (Cow::Borrowed(self.buf), width, height)
}
let mut buf = Vec::with_capacity(width*height);
for row in self.rows() {
buf.extend_from_slice(row);
}
(Cow::Owned(buf), width, height)
}
}
impl<'a, T> ImgRefMut<'a, T> {
/// Turn this into immutable reference, and slice a subregion of it
#[inline]
#[allow(deprecated)]
#[must_use]
pub fn sub_image(&'a mut self, left: usize, top: usize, width: usize, height: usize) -> ImgRef<'a, T> {
self.as_ref().sub_image(left, top, width, height)
}
/// Trim this image without copying.
/// Note that mutable borrows are exclusive, so it's not possible to have more than
/// one mutable subimage at a time.
#[inline]
#[allow(deprecated)]
#[must_use]
#[track_caller]
pub fn sub_image_mut(&mut self, left: usize, top: usize, width: usize, height: usize) -> ImgRefMut<'_, T> {
assert!(top+height <= self.height());
assert!(left+width <= self.width());
let (start, end, stride) = sub_image(left, top, width, height, self.stride(), self.buf.len());
let buf = &mut self.buf[start..end];
ImgRefMut::new_stride(buf, width, height, stride)
}
/// Make mutable reference immutable
#[inline]
#[must_use]
pub fn as_ref(&self) -> ImgRef<'_, T> {
self.new_buf(self.buf().as_ref())
}
}
impl<'a, T: Copy> ImgRef<'a, T> {
/// Iterate `width*height` pixels in the `Img`, ignoring padding area
///
/// If you want to iterate in parallel, parallelize `rows()` instead.
///
/// # Panics
///
/// if width is 0
#[inline]
pub fn pixels(&self) -> PixelsIter<'_, T> {
PixelsIter::new(*self)
}
}
impl<'a, T> ImgRef<'a, T> {
/// Iterate `width*height` pixels in the `Img`, by reference, ignoring padding area
///
/// If you want to iterate in parallel, parallelize `rows()` instead.
///
/// # Panics
///
/// if width is 0
#[inline]
pub fn pixels_ref(&self) -> PixelsRefIter<'_, T> {
PixelsRefIter::new(*self)
}
}
impl<'a, T: Copy> ImgRefMut<'a, T> {
/// # Panics
///
/// If you want to iterate in parallel, parallelize `rows()` instead.
///
/// if width is 0
#[inline]
pub fn pixels(&self) -> PixelsIter<'_, T> {
PixelsIter::new(self.as_ref())
}
/// If you want to iterate in parallel, parallelize `rows()` instead.
/// # Panics
///
/// if width is 0
#[inline]
pub fn pixels_mut(&mut self) -> PixelsIterMut<'_, T> {
PixelsIterMut::new(self)
}
}
impl<T: Copy> ImgVec<T> {
/// If you want to iterate in parallel, parallelize `rows()` instead.
/// # Panics
///
/// if width is 0
#[inline]
pub fn pixels(&self) -> PixelsIter<'_, T> {
PixelsIter::new(self.as_ref())
}
/// If you want to iterate in parallel, parallelize `rows()` instead.
/// # Panics
///
/// if width is 0
#[inline]
pub fn pixels_mut(&mut self) -> PixelsIterMut<'_, T> {
PixelsIterMut::new(&mut self.as_mut())
}
}
impl<'a, T> ImgRefMut<'a, T> {
/// Iterate over whole rows as slices
///
/// # Panics
///
/// if stride is 0
#[inline]
pub fn rows(&self) -> RowsIter<'_, T> {
self.rows_buf_internal(&self.buf()[..])
}
/// Iterate over whole rows as slices
///
/// # Panics
///
/// if stride is 0
#[inline]
#[allow(deprecated)]
pub fn rows_mut(&mut self) -> RowsIterMut<'_, T> {
let stride = self.stride();
let width = self.width();
let height = self.height();
let non_padded = &mut self.buf[0..stride * height + width - stride];
RowsIterMut {
width,
inner: non_padded.chunks_mut(stride),
}
}
}
/// Deprecated. Use .rows() or .pixels() iterators which are more predictable
#[cfg(feature = "deprecated")]
impl<Container> IntoIterator for Img<Container> where Container: IntoIterator {
type Item = Container::Item;
type IntoIter = Container::IntoIter;
/// Deprecated. Use .rows() or .pixels() iterators which are more predictable
fn into_iter(self) -> Container::IntoIter {
self.into_buf().into_iter()
}
}
impl<T> ImgVec<T> {
/// Create a mutable view into a region within the image. See `sub_image()` for read-only views.
#[allow(deprecated)]
#[must_use]
#[track_caller]
pub fn sub_image_mut(&mut self, left: usize, top: usize, width: usize, height: usize) -> ImgRefMut<'_, T> {
assert!(top+height <= self.height());
assert!(left+width <= self.width());
let start = self.stride * top + left;
let min_buf_size = if self.height > 0 {self.stride * height + width - self.stride} else {0};
let buf = &mut self.buf[start .. start + min_buf_size];
Img::new_stride(buf, width, height, self.stride)
}
#[inline]
#[must_use]
/// Make a reference for a part of the image, without copying any pixels.
pub fn sub_image(&self, left: usize, top: usize, width: usize, height: usize) -> ImgRef<'_, T> {
self.as_ref().sub_image(left, top, width, height)
}
/// Make a reference to this image to pass it to functions without giving up ownership
///
/// The reference should be passed by value (`ImgRef`, not `&ImgRef`).
///
/// If you need a mutable reference, see `as_mut()` and `sub_image_mut()`
#[inline]
#[must_use]
pub fn as_ref(&self) -> ImgRef<'_, T> {
self.new_buf(self.buf().as_ref())
}
/// Make a mutable reference to the entire image
///
/// The reference should be passed by value (`ImgRefMut`, not `&mut ImgRefMut`).
///
/// See also `sub_image_mut()` and `rows_mut()`
#[inline]
pub fn as_mut(&mut self) -> ImgRefMut<'_, T> {
let width = self.width();
let height = self.height();
let stride = self.stride();
Img::new_stride(self.buf_mut().as_mut(), width, height, stride)
}
#[deprecated(note = "Size of this buffer may be unpredictable. Use .rows() instead")]
#[cfg(feature = "deprecated")]
#[doc(hidden)]
pub fn iter(&self) -> slice::Iter<'_, T> {
self.buf().iter()
}
/// Iterate over rows of the image as slices
///
/// Each slice is guaranteed to be exactly `width` pixels wide.
///
/// This iterator is a good candidate for parallelization (e.g. rayon's `par_bridge()`)
#[inline]
pub fn rows(&self) -> RowsIter<'_, T> {
self.rows_buf_internal(self.buf())
}
/// Iterate over rows of the image as mutable slices
///
/// Each slice is guaranteed to be exactly `width` pixels wide.
///
/// This iterator is a good candidate for parallelization (e.g. rayon's `par_bridge()`)
#[inline]
#[allow(deprecated)]
pub fn rows_mut(&mut self) -> RowsIterMut<'_, T> {
let stride = self.stride();
let width = self.width();
let height = self.height();
let non_padded = &mut self.buf[0..stride * height + width - stride];
RowsIterMut {
width,
inner: non_padded.chunks_mut(stride),
}
}
}
impl<Container> Img<Container> {
/// Same as `new()`, except each row is located `stride` number of pixels after the previous one.
///
/// Stride can be equal to `width` or larger. If it's larger, then pixels between end of previous row and start of the next are considered a padding, and may be ignored.
///
/// The `Container` is usually a `Vec` or a slice.
#[inline]
#[allow(deprecated)]
#[track_caller]
pub fn new_stride(buf: Container, width: usize, height: usize, stride: usize) -> Self {
assert!(stride > 0);
assert!(stride >= width as usize);
debug_assert!(height < <u32>::max_value() as usize);
debug_assert!(width < <u32>::max_value() as usize);
Img {
buf,
width: width as u32,
height: height as u32,
stride,
}
}
/// Create new image with `Container` (which can be `Vec`, `&[]` or something else) with given `width` and `height` in pixels.
///
/// Assumes the pixels in container are contiguous, layed out row by row with `width` pixels per row and at least `height` rows.
///
/// If the container is larger than `width`×`height` pixels, the extra rows are a considered a padding and may be ignored.
#[inline]
pub fn new(buf: Container, width: usize, height: usize) -> Self {
Self::new_stride(buf, width, height, width)
}
}
impl<T: Copy> Img<Vec<T>> {
/// Returns the buffer, width, height. Guarantees that the buffer is contiguous,
/// i.e. it's `width*height` elements long, and `[x + y*width]` addresses each pixel.
///
/// Efficiently performs operation in-place. For other containers use `pixels().collect()`.
#[allow(deprecated)]
#[must_use]
pub fn into_contiguous_buf(mut self) -> (Vec<T>, usize, usize) {
let (_, w, h) = self.as_contiguous_buf();
(self.buf, w, h)
}
/// Returns a reference to the buffer, width, height. Guarantees that the buffer is contiguous,
/// i.e. it's `width*height` elements long, and `[x + y*width]` addresses each pixel.
///
/// Efficiently performs operation in-place. For other containers use `pixels().collect()`.
#[allow(deprecated)]
#[must_use]
pub fn as_contiguous_buf(&mut self) -> (&[T], usize, usize) {
let width = self.width();
let height = self.height();
let stride = self.stride();
if width != stride {
for row in 1..height {
self.buf.copy_within(row * stride .. row * stride + width, row * width);
}
}
self.buf.truncate(width * height);
(&mut self.buf, width, height)
}
}
impl<OldContainer> Img<OldContainer> {
/// A convenience method for creating an image of the same size and stride, but with a new buffer.
#[inline]
#[track_caller]
pub fn map_buf<NewContainer, OldPixel, NewPixel, F>(self, callback: F) -> Img<NewContainer>
where NewContainer: AsRef<[NewPixel]>, OldContainer: AsRef<[OldPixel]>, F: FnOnce(OldContainer) -> NewContainer {
let width = self.width();
let height = self.height();
let stride = self.stride();
let old_buf_len = self.buf().as_ref().len();
#[allow(deprecated)]
let new_buf = callback(self.buf);
assert_eq!(old_buf_len, new_buf.as_ref().len());
Img::new_stride(new_buf, width, height, stride)
}
/// A convenience method for creating an image of the same size and stride, but with a new buffer.
#[inline]
#[track_caller]
pub fn new_buf<NewContainer, OldPixel, NewPixel>(&self, new_buf: NewContainer) -> Img<NewContainer>
where NewContainer: AsRef<[NewPixel]>, OldContainer: AsRef<[OldPixel]> {
assert_eq!(self.buf().as_ref().len(), new_buf.as_ref().len());
Img::new_stride(new_buf, self.width(), self.height(), self.stride())
}
}
impl<T: Clone> From<Img<Cow<'_, [T]>>> for Img<Vec<T>> {
#[allow(deprecated)]
fn from(img: Img<Cow<'_, [T]>>) -> Self {
Img {
width: img.width,
height: img.height,
stride: img.stride,
buf: img.buf.into_owned(),
}
}
}
impl<T: Clone> From<ImgVec<T>> for Img<Cow<'static, [T]>> {
#[allow(deprecated)]
fn from(img: ImgVec<T>) -> Self {
Img {
width: img.width,
height: img.height,
stride: img.stride,
buf: img.buf.into(),
}
}
}
impl<'a, T: Clone> From<ImgRef<'a, T>> for Img<Cow<'a, [T]>> {
#[allow(deprecated)]
fn from(img: ImgRef<'a, T>) -> Self {
Img {
buf: img.buf.into(),
width: img.width,
height: img.height,
stride: img.stride,
}
}
}
impl<T: Clone> Img<Cow<'_, [T]>> {
/// Convert underlying buffer to owned (e.g. slice to vec)
///
/// See also `to_contiguous_buf().0.into_owned()`
#[allow(deprecated)]
pub fn into_owned(self) -> ImgVec<T> {
match self.buf {
Cow::Borrowed(_) => {
let tmp = self.as_ref();
let (buf, w, h) = tmp.to_contiguous_buf();
ImgVec::new(buf.into_owned(), w, h)
},
Cow::Owned(buf) => Img {
buf,
width: self.width,
height: self.height,
stride: self.stride,
},
}
}
}
impl<T> Img<T> where T: ToOwned {
/// Convert underlying buffer to owned (e.g. slice to vec)
///
/// See also `to_contiguous_buf().0.into_owned()`
#[allow(deprecated)]
pub fn to_owned(&self) -> Img<T::Owned> {
Img {
buf: self.buf.to_owned(),
width: self.width,
height: self.height,
stride: self.stride,
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use alloc::vec;
mod with_opinionated_container {
use super::*;
struct IDontDeriveAnything;
#[test]
fn compiles() {
let _ = Img::new(IDontDeriveAnything, 1, 1);
}
}
#[test]
fn with_vec() {
let bytes = vec![0u8;20];
let old = Img::new_stride(bytes, 10,2,10);
let _ = old.new_buf(vec![6u16;20]);
}
#[test]
fn zero() {
let bytes = vec![0u8];
let mut img = Img::new_stride(bytes,0,0,1);
let _ = img.sub_image(0,0,0,0);
let _ = img.sub_image_mut(0,0,0,0);
let _ = img.as_ref();
}
#[test]
fn zero_width() {
let bytes = vec![0u8];
let mut img = Img::new_stride(bytes,0,1,1);
let _ = img.sub_image(0,1,0,0);
let _ = img.sub_image_mut(0,0,0,1);
}
#[test]
fn zero_height() {
let bytes = vec![0u8];
let mut img = Img::new_stride(bytes,1,0,1);
assert_eq!(0, img.rows().count());
let _ = img.sub_image(1,0,0,0);
let _ = img.sub_image_mut(0,0,1,0);
}
#[test]
#[allow(deprecated)]
fn with_slice() {
let bytes = vec![0u8;20];
let _ = Img::new_stride(bytes.as_slice(), 10,2,10);
let vec = ImgVec::new_stride(bytes, 10,2,10);
#[cfg(feature = "deprecated")]
for _ in vec.iter() {}
assert_eq!(2, vec.rows().count());
for _ in vec.as_ref().buf().iter() {}
#[cfg(feature = "deprecated")]
for _ in vec {}
}
#[test]
fn sub() {
let img = Img::new_stride(vec![1,2,3,4,
5,6,7,8,
9], 3, 2, 4);
assert_eq!(img.buf()[img.stride()], 5);
assert_eq!(img.buf()[img.stride() + img.width()-1], 7);
assert_eq!(img.pixels().count(), img.width() * img.height());
assert_eq!(img.pixels().sum::<i32>(), 24);
{
let refimg = img.as_ref();
let refimg2 = refimg; // Test is Copy
// sub-image with stride hits end of the buffer
let s1 = refimg.sub_image(1, 0, refimg.width()-1, refimg.height());
let _ = s1.sub_image(1, 0, s1.width()-1, s1.height());
let subimg = refimg.sub_image(1, 1, 2, 1);
assert_eq!(subimg.pixels().count(), subimg.width() * subimg.height());
assert_eq!(subimg.buf()[0], 6);
assert_eq!(subimg.stride(), refimg2.stride());
assert!(subimg.stride() * subimg.height() + subimg.width() - subimg.stride() <= subimg.buf().len());
assert_eq!(refimg.buf()[0], 1);
assert_eq!(1, subimg.rows().count());
}
let mut img = img;
let mut subimg = img.sub_image_mut(1, 1, 2, 1);
assert_eq!(1, subimg.rows().count());
assert_eq!(1, subimg.rows_mut().count());
assert_eq!(1, subimg.rows_mut().rev().count());
assert_eq!(1, subimg.rows_mut().fuse().rev().count());
assert_eq!(subimg.buf()[0], 6);
}
#[test]
fn rows() {
let img = ImgVec::new_stride(vec![0u8; 10000], 10, 15, 100);
assert_eq!(img.height(), img.rows().count());
assert_eq!(img.height(), img.rows().rev().count());
assert_eq!(img.height(), img.rows().fuse().rev().count());
}
#[test]
fn mut_pixels() {
for y in 1..15 {
for x in 1..10 {
let mut img = ImgVec::new_stride(vec![0u8; 10000], x, y, 100);
assert_eq!(x*y, img.pixels_mut().count());
assert_eq!(x*y, img.as_mut().pixels().count());
assert_eq!(x*y, img.as_mut().pixels_mut().count());
assert_eq!(x*y, img.as_mut().as_ref().pixels().count());
}
}
}
#[test]
fn into_contiguous_buf() {
for in_h in [1, 2, 3, 38, 39, 40, 41].iter().copied() {
for in_w in [1, 2, 3, 120, 121].iter().copied() {
for stride in [in_w, 121, 122, 166, 242, 243].iter().copied() {
let img = ImgVec::new_stride((0..10000).map(|x| x as u8).collect(), in_w, in_h, stride)
.map_buf(|x| x);
let pixels: Vec<_> = img.pixels().collect();
let (buf, w, h) = img.into_contiguous_buf();
assert_eq!(pixels, buf);
assert_eq!(in_w*in_h, buf.len());
assert_eq!(10000, buf.capacity());
assert_eq!(in_w, w);
assert_eq!(in_h, h);
}
}
}
let img = ImgVec::new((0..55*33).map(|x| x as u8).collect(), 55, 33);
let pixels: Vec<_> = img.pixels().collect();
let tmp = img.as_ref();
let (buf, ..) = tmp.to_contiguous_buf();
assert_eq!(&pixels[..], &buf[..]);
let (buf, ..) = img.into_contiguous_buf();
assert_eq!(pixels, buf);
}
}