pic_scale/colors/
lch_scaler.rs

1/*
2 * Copyright (c) Radzivon Bartoshyk. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification,
5 * are permitted provided that the following conditions are met:
6 *
7 * 1.  Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * 2.  Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 *
14 * 3.  Neither the name of the copyright holder nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
25 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30use colorutils_rs::{
31    SRGB_TO_XYZ_D65, TransferFunction, XYZ_TO_SRGB_D65, lch_to_rgb, lch_with_alpha_to_rgba,
32    rgb_to_lch, rgba_to_lch_with_alpha,
33};
34
35use crate::pic_scale_error::{PicScaleError, try_vec};
36use crate::scaler::ScalingF32;
37use crate::support::check_image_size_overflow;
38use crate::{ImageStore, ImageStoreMut, ResamplingFunction, Scaler, Scaling, ThreadingPolicy};
39
40#[derive(Debug, Copy, Clone)]
41/// Converts image to *CIE LCH(uv)* components scales it and convert back
42pub struct LChScaler {
43    pub(crate) scaler: Scaler,
44}
45
46impl LChScaler {
47    pub fn new(filter: ResamplingFunction) -> Self {
48        LChScaler {
49            scaler: Scaler::new(filter),
50        }
51    }
52
53    fn rgba_to_lcha<'a>(store: &ImageStore<'a, u8, 4>) -> ImageStore<'a, f32, 4> {
54        let mut source_slice = vec![f32::default(); 4 * store.width * store.height];
55        let lab_stride = store.width as u32 * 4u32 * size_of::<f32>() as u32;
56        rgba_to_lch_with_alpha(
57            store.buffer.as_ref(),
58            store.width as u32 * 4u32,
59            &mut source_slice,
60            lab_stride,
61            store.width as u32,
62            store.height as u32,
63            &SRGB_TO_XYZ_D65,
64            TransferFunction::Srgb,
65        );
66
67        ImageStore::<f32, 4> {
68            buffer: std::borrow::Cow::Owned(source_slice),
69            channels: 4,
70            width: store.width,
71            height: store.height,
72            stride: store.width * 4,
73            bit_depth: store.bit_depth,
74        }
75    }
76
77    fn lcha_to_srgba<'a>(store: &ImageStoreMut<'a, f32, 4>, into: &mut ImageStoreMut<'a, u8, 4>) {
78        lch_with_alpha_to_rgba(
79            store.buffer.borrow(),
80            store.width as u32 * 4u32 * size_of::<f32>() as u32,
81            into.buffer.borrow_mut(),
82            store.width as u32 * 4u32,
83            store.width as u32,
84            store.height as u32,
85            &XYZ_TO_SRGB_D65,
86            TransferFunction::Srgb,
87        );
88    }
89}
90
91impl Scaling for LChScaler {
92    fn set_threading_policy(&mut self, threading_policy: ThreadingPolicy) {
93        self.scaler.set_threading_policy(threading_policy)
94    }
95
96    fn resize_plane<'a>(
97        &'a self,
98        _: &ImageStore<'a, u8, 1>,
99        _: &mut ImageStoreMut<'a, u8, 1>,
100    ) -> Result<(), PicScaleError> {
101        unimplemented!()
102    }
103
104    fn resize_cbcr8<'a>(
105        &'a self,
106        _: &ImageStore<'a, u8, 2>,
107        _: &mut ImageStoreMut<'a, u8, 2>,
108    ) -> Result<(), PicScaleError> {
109        unimplemented!()
110    }
111
112    fn resize_gray_alpha<'a>(
113        &'a self,
114        _: &ImageStore<'a, u8, 2>,
115        _: &mut ImageStoreMut<'a, u8, 2>,
116        _: bool,
117    ) -> Result<(), PicScaleError> {
118        unimplemented!()
119    }
120
121    fn resize_rgb<'a>(
122        &'a self,
123        store: &ImageStore<'a, u8, 3>,
124        into: &mut ImageStoreMut<'a, u8, 3>,
125    ) -> Result<(), PicScaleError> {
126        let new_size = into.get_size();
127        into.validate()?;
128        store.validate()?;
129        if store.width == 0 || store.height == 0 || new_size.width == 0 || new_size.height == 0 {
130            return Err(PicScaleError::ZeroImageDimensions);
131        }
132
133        if check_image_size_overflow(store.width, store.height, store.channels) {
134            return Err(PicScaleError::SourceImageIsTooLarge);
135        }
136
137        if check_image_size_overflow(new_size.width, new_size.height, store.channels) {
138            return Err(PicScaleError::DestinationImageIsTooLarge);
139        }
140
141        if store.width == new_size.width && store.height == new_size.height {
142            store.copied_to_mut(into);
143            return Ok(());
144        }
145
146        const CN: usize = 3;
147
148        let mut target_vertical = try_vec![f32::default(); store.width * store.height * CN];
149
150        let mut lab_store =
151            ImageStoreMut::<f32, CN>::from_slice(&mut target_vertical, store.width, store.height)?;
152        lab_store.bit_depth = into.bit_depth;
153
154        let lab_stride = lab_store.width as u32 * CN as u32 * std::mem::size_of::<f32>() as u32;
155        rgb_to_lch(
156            store.buffer.as_ref(),
157            store.width as u32 * CN as u32,
158            lab_store.buffer.borrow_mut(),
159            lab_stride,
160            lab_store.width as u32,
161            lab_store.height as u32,
162            &SRGB_TO_XYZ_D65,
163            TransferFunction::Srgb,
164        );
165
166        let new_immutable_store = ImageStore::<f32, CN> {
167            buffer: std::borrow::Cow::Owned(target_vertical),
168            channels: CN,
169            width: store.width,
170            height: store.height,
171            stride: store.width * CN,
172            bit_depth: into.bit_depth,
173        };
174
175        let mut new_store = ImageStoreMut::<f32, CN>::try_alloc(into.width, into.height)?;
176        self.scaler
177            .resize_rgb_f32(&new_immutable_store, &mut new_store)?;
178
179        let new_lab_stride = new_store.width as u32 * CN as u32 * std::mem::size_of::<f32>() as u32;
180
181        lch_to_rgb(
182            new_store.buffer.borrow(),
183            new_lab_stride,
184            into.buffer.borrow_mut(),
185            into.width as u32 * CN as u32,
186            new_store.width as u32,
187            new_store.height as u32,
188            &XYZ_TO_SRGB_D65,
189            TransferFunction::Srgb,
190        );
191        Ok(())
192    }
193
194    fn resize_rgba<'a>(
195        &'a self,
196        store: &ImageStore<'a, u8, 4>,
197        into: &mut ImageStoreMut<'a, u8, 4>,
198        premultiply_alpha: bool,
199    ) -> Result<(), PicScaleError> {
200        let new_size = into.get_size();
201        into.validate()?;
202        store.validate()?;
203        if store.width == 0 || store.height == 0 || new_size.width == 0 || new_size.height == 0 {
204            return Err(PicScaleError::ZeroImageDimensions);
205        }
206
207        if check_image_size_overflow(store.width, store.height, store.channels) {
208            return Err(PicScaleError::SourceImageIsTooLarge);
209        }
210
211        if check_image_size_overflow(new_size.width, new_size.height, store.channels) {
212            return Err(PicScaleError::DestinationImageIsTooLarge);
213        }
214
215        if store.width == new_size.width && store.height == new_size.height {
216            store.copied_to_mut(into);
217            return Ok(());
218        }
219
220        let lab_store = Self::rgba_to_lcha(store);
221        let mut new_target_store = ImageStoreMut::try_alloc(new_size.width, new_size.height)?;
222
223        self.scaler
224            .resize_rgba_f32(&lab_store, &mut new_target_store, premultiply_alpha)?;
225        Self::lcha_to_srgba(&new_target_store, into);
226        Ok(())
227    }
228}