/rust/registry/src/index.crates.io-1949cf8c6b5b557f/jpeg-encoder-0.7.0/src/image_buffer.rs

Source
#![allow(clippy::identity_op)]

use alloc::vec::Vec;

use crate::encoder::JpegColorType;

/// Conversion from RGB to YCbCr
#[inline]
pub fn rgb_to_ycbcr(r: u8, g: u8, b: u8) -> (u8, u8, u8) {
    // To avoid floating point math this scales everything by 2^16 which gives
    // a precision of approx 4 digits.
    //
    // Non scaled conversion:
    // Y  =  0.29900 * R + 0.58700 * G + 0.11400 * B
    // Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B  + 128
    // Cr =  0.50000 * R - 0.41869 * G - 0.08131 * B  + 128

    let r = r as i32;
    let g = g as i32;
    let b = b as i32;

    let y = 19595 * r + 38470 * g + 7471 * b;
    let cb = -11059 * r - 21709 * g + 32768 * b + (128 << 16);
    let cr = 32768 * r - 27439 * g - 5329 * b + (128 << 16);

    let y = (y + 0x7FFF) >> 16;
    let cb = (cb + 0x7FFF) >> 16;
    let cr = (cr + 0x7FFF) >> 16;

    (y as u8, cb as u8, cr as u8)
}

/// Conversion from CMYK to YCCK (YCbCrK)
#[inline]
pub fn cmyk_to_ycck(c: u8, m: u8, y: u8, k: u8) -> (u8, u8, u8, u8) {
    let (y, cb, cr) = rgb_to_ycbcr(c, m, y);
    (y, cb, cr, 255 - k)
}

/// # Buffer used as input value for image encoding
///
/// Image encoding with [Encoder::encode_image](crate::Encoder::encode_image) needs an ImageBuffer
/// as input for the image data. For convenience the [Encoder::encode](crate::Encoder::encode)
/// function contains implementations for common byte based pixel formats.
/// Users that needs other pixel formats or don't have the data available as byte slices
/// can create their own buffer implementations.
///
/// ## Example: ImageBuffer implementation for RgbImage from the `image` crate
/// ```no_compile
/// use image::RgbImage;
/// use jpeg_encoder::{ImageBuffer, JpegColorType, rgb_to_ycbcr};
///
/// pub struct RgbImageBuffer {
///     image: RgbImage,
/// }
///
/// impl ImageBuffer for RgbImageBuffer {
///     fn get_jpeg_color_type(&self) -> JpegColorType {
///         // Rgb images are encoded as YCbCr in JFIF files
///         JpegColorType::Ycbcr
///     }
///
///     fn width(&self) -> u16 {
///         self.image.width() as u16
///     }
///
///     fn height(&self) -> u16 {
///         self.image.height() as u16
///     }
///
///     fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]){
///         for x in 0..self.width() {
///             let pixel = self.image.get_pixel(x as u32 ,y as u32);
///
///             let (y,cb,cr) = rgb_to_ycbcr(pixel[0], pixel[1], pixel[2]);
///
///             // For YCbCr the 4th buffer is not used
///             buffers[0].push(y);
///             buffers[1].push(cb);
///             buffers[2].push(cr);
///         }
///     }
/// }
///
/// ```
pub trait ImageBuffer {
    /// The color type used in the image encoding
    fn get_jpeg_color_type(&self) -> JpegColorType;

    /// Width of the image
    fn width(&self) -> u16;

    /// Height of the image
    fn height(&self) -> u16;

    /// Add color values for the row to color component buffers
    fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]);
}

pub(crate) struct GrayImage<'a>(pub &'a [u8], pub u16, pub u16);

impl<'a> ImageBuffer for GrayImage<'a> {
    fn get_jpeg_color_type(&self) -> JpegColorType {
        JpegColorType::Luma
    }

    fn width(&self) -> u16 {
        self.1
    }

    fn height(&self) -> u16 {
        self.2
    }

    fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
        let line = get_line(self.0, y, self.width(), 1);

        for &pixel in line {
            buffers[0].push(pixel);
        }
    }
}

#[inline(always)]
fn get_line(data: &[u8], y: u16, width: u16, num_colors: usize) -> &[u8] {
    let width = usize::from(width);
    let y = usize::from(y);

    let start = y * width * num_colors;
    let end = start + width * num_colors;

    &data[start..end]
}

macro_rules! ycbcr_image {
    ($name:ident, $num_colors:expr, $o1:expr, $o2:expr, $o3:expr) => {
        pub struct $name<'a>(pub &'a [u8], pub u16, pub u16);

        impl<'a> ImageBuffer for $name<'a> {
            fn get_jpeg_color_type(&self) -> JpegColorType {
                JpegColorType::Ycbcr
            }

            fn width(&self) -> u16 {
                self.1
            }

            fn height(&self) -> u16 {
                self.2
            }

            #[inline(always)]
            fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
                let line = get_line(self.0, y, self.width(), $num_colors);

                // Doing the convertion in chunks allows the compiler to vectorize the code
                // A size of 16 seems optimal for SSE and AVX capable hardware
                const CHUNK_SIZE: usize = 16;

                let mut y_buffer = [0; CHUNK_SIZE];
                let mut cb_buffer = [0; CHUNK_SIZE];
                let mut cr_buffer = [0; CHUNK_SIZE];

                for chuck in line.chunks_exact($num_colors * CHUNK_SIZE) {
                    for i in (0..CHUNK_SIZE) {
                        let (y, cb, cr) = rgb_to_ycbcr(
                            chuck[i * $num_colors + $o1],
                            chuck[i * $num_colors + $o2],
                            chuck[i * $num_colors + $o3],
                        );

                        y_buffer[i] = y;
                        cb_buffer[i] = cb;
                        cr_buffer[i] = cr;
                    }

                    buffers[0].extend_from_slice(&y_buffer);
                    buffers[1].extend_from_slice(&cb_buffer);
                    buffers[2].extend_from_slice(&cr_buffer);
                }

                // Add the remaining pixels in case the number of
                // pixels is not a multiple of CHUNK_SIZE
                let pixel = line.len() / $num_colors;
                for i in pixel / CHUNK_SIZE * CHUNK_SIZE..pixel {
                    let (y, cb, cr) = rgb_to_ycbcr(
                        line[i * $num_colors + $o1],
                        line[i * $num_colors + $o2],
                        line[i * $num_colors + $o3],
                    );

                    buffers[0].push(y);
                    buffers[1].push(cb);
                    buffers[2].push(cr);
                }
            }
        }
    };
}

ycbcr_image!(RgbImage, 3, 0, 1, 2);
ycbcr_image!(RgbaImage, 4, 0, 1, 2);
ycbcr_image!(BgrImage, 3, 2, 1, 0);
ycbcr_image!(BgraImage, 4, 2, 1, 0);

pub(crate) struct YCbCrImage<'a>(pub &'a [u8], pub u16, pub u16);

impl<'a> ImageBuffer for YCbCrImage<'a> {
    fn get_jpeg_color_type(&self) -> JpegColorType {
        JpegColorType::Ycbcr
    }

    fn width(&self) -> u16 {
        self.1
    }

    fn height(&self) -> u16 {
        self.2
    }

    fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
        let line = get_line(self.0, y, self.width(), 3);

        for pixel in line.chunks_exact(3) {
            buffers[0].push(pixel[0]);
            buffers[1].push(pixel[1]);
            buffers[2].push(pixel[2]);
        }
    }
}

pub(crate) struct CmykImage<'a>(pub &'a [u8], pub u16, pub u16);

impl<'a> ImageBuffer for CmykImage<'a> {
    fn get_jpeg_color_type(&self) -> JpegColorType {
        JpegColorType::Cmyk
    }

    fn width(&self) -> u16 {
        self.1
    }

    fn height(&self) -> u16 {
        self.2
    }

    fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
        let line = get_line(self.0, y, self.width(), 4);

        for pixel in line.chunks_exact(4) {
            buffers[0].push(255 - pixel[0]);
            buffers[1].push(255 - pixel[1]);
            buffers[2].push(255 - pixel[2]);
            buffers[3].push(255 - pixel[3]);
        }
    }
}

pub(crate) struct CmykAsYcckImage<'a>(pub &'a [u8], pub u16, pub u16);

impl<'a> ImageBuffer for CmykAsYcckImage<'a> {
    fn get_jpeg_color_type(&self) -> JpegColorType {
        JpegColorType::Ycck
    }

    fn width(&self) -> u16 {
        self.1
    }

    fn height(&self) -> u16 {
        self.2
    }

    fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
        let line = get_line(self.0, y, self.width(), 4);

        for pixel in line.chunks_exact(4) {
            let (y, cb, cr, k) = cmyk_to_ycck(pixel[0], pixel[1], pixel[2], pixel[3]);

            buffers[0].push(y);
            buffers[1].push(cb);
            buffers[2].push(cr);
            buffers[3].push(k);
        }
    }
}

pub(crate) struct YcckImage<'a>(pub &'a [u8], pub u16, pub u16);

impl<'a> ImageBuffer for YcckImage<'a> {
    fn get_jpeg_color_type(&self) -> JpegColorType {
        JpegColorType::Ycck
    }

    fn width(&self) -> u16 {
        self.1
    }

    fn height(&self) -> u16 {
        self.2
    }

    fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
        let line = get_line(self.0, y, self.width(), 4);

        for pixel in line.chunks_exact(4) {
            buffers[0].push(pixel[0]);
            buffers[1].push(pixel[1]);
            buffers[2].push(pixel[2]);
            buffers[3].push(pixel[3]);
        }
    }
}

#[cfg(test)]
mod tests {
    use crate::rgb_to_ycbcr;

    fn assert_rgb_to_ycbcr(rgb: [u8; 3], ycbcr: [u8; 3]) {
        let (y, cb, cr) = rgb_to_ycbcr(rgb[0], rgb[1], rgb[2]);
        assert_eq!([y, cb, cr], ycbcr);
    }

    #[test]
    fn test_rgb_to_ycbcr() {
        assert_rgb_to_ycbcr([0, 0, 0], [0, 128, 128]);
        assert_rgb_to_ycbcr([255, 255, 255], [255, 128, 128]);
        assert_rgb_to_ycbcr([255, 0, 0], [76, 85, 255]);
        assert_rgb_to_ycbcr([0, 255, 0], [150, 44, 21]);
        assert_rgb_to_ycbcr([0, 0, 255], [29, 255, 107]);

        // Values taken from libjpeg for a common image

        assert_rgb_to_ycbcr([59, 109, 6], [82, 85, 111]);
        assert_rgb_to_ycbcr([29, 60, 11], [45, 109, 116]);
        assert_rgb_to_ycbcr([57, 114, 26], [87, 94, 107]);
        assert_rgb_to_ycbcr([30, 60, 6], [45, 106, 117]);
        assert_rgb_to_ycbcr([41, 75, 11], [58, 102, 116]);
        assert_rgb_to_ycbcr([145, 184, 108], [164, 97, 115]);
        assert_rgb_to_ycbcr([33, 85, 7], [61, 98, 108]);
        assert_rgb_to_ycbcr([61, 90, 40], [76, 108, 118]);
        assert_rgb_to_ycbcr([75, 127, 45], [102, 96, 109]);
        assert_rgb_to_ycbcr([30, 56, 14], [43, 111, 118]);
        assert_rgb_to_ycbcr([106, 142, 81], [124, 104, 115]);
        assert_rgb_to_ycbcr([35, 59, 11], [46, 108, 120]);
        assert_rgb_to_ycbcr([170, 203, 123], [184, 94, 118]);
        assert_rgb_to_ycbcr([45, 87, 16], [66, 100, 113]);
        assert_rgb_to_ycbcr([59, 109, 21], [84, 92, 110]);
        assert_rgb_to_ycbcr([100, 167, 36], [132, 74, 105]);
        assert_rgb_to_ycbcr([17, 53, 5], [37, 110, 114]);
        assert_rgb_to_ycbcr([226, 244, 220], [236, 119, 121]);
        assert_rgb_to_ycbcr([192, 214, 120], [197, 85, 125]);
        assert_rgb_to_ycbcr([63, 107, 22], [84, 93, 113]);
        assert_rgb_to_ycbcr([44, 78, 19], [61, 104, 116]);
        assert_rgb_to_ycbcr([72, 106, 54], [90, 108, 115]);
        assert_rgb_to_ycbcr([99, 123, 73], [110, 107, 120]);
        assert_rgb_to_ycbcr([188, 216, 148], [200, 99, 120]);
        assert_rgb_to_ycbcr([19, 46, 7], [33, 113, 118]);
        assert_rgb_to_ycbcr([56, 95, 40], [77, 107, 113]);
        assert_rgb_to_ycbcr([81, 120, 56], [101, 103, 114]);
        assert_rgb_to_ycbcr([9, 30, 0], [20, 117, 120]);
        assert_rgb_to_ycbcr([90, 118, 46], [101, 97, 120]);
        assert_rgb_to_ycbcr([24, 52, 0], [38, 107, 118]);
        assert_rgb_to_ycbcr([32, 69, 9], [51, 104, 114]);
        assert_rgb_to_ycbcr([74, 134, 33], [105, 88, 106]);
        assert_rgb_to_ycbcr([37, 74, 7], [55, 101, 115]);
        assert_rgb_to_ycbcr([69, 119, 31], [94, 92, 110]);
        assert_rgb_to_ycbcr([63, 112, 21], [87, 91, 111]);
        assert_rgb_to_ycbcr([90, 148, 17], [116, 72, 110]);
        assert_rgb_to_ycbcr([50, 97, 30], [75, 102, 110]);
        assert_rgb_to_ycbcr([99, 129, 72], [114, 105, 118]);
        assert_rgb_to_ycbcr([161, 196, 57], [170, 64, 122]);
        assert_rgb_to_ycbcr([10, 26, 1], [18, 118, 122]);
        assert_rgb_to_ycbcr([87, 128, 68], [109, 105, 112]);
        assert_rgb_to_ycbcr([111, 155, 73], [132, 94, 113]);
        assert_rgb_to_ycbcr([33, 75, 11], [55, 103, 112]);
        assert_rgb_to_ycbcr([70, 122, 51], [98, 101, 108]);
        assert_rgb_to_ycbcr([22, 74, 3], [50, 101, 108]);
        assert_rgb_to_ycbcr([88, 142, 45], [115, 89, 109]);
        assert_rgb_to_ycbcr([66, 107, 40], [87, 101, 113]);
        assert_rgb_to_ycbcr([18, 45, 0], [32, 110, 118]);
        assert_rgb_to_ycbcr([163, 186, 88], [168, 83, 124]);
        assert_rgb_to_ycbcr([47, 104, 4], [76, 88, 108]);
        assert_rgb_to_ycbcr([147, 211, 114], [181, 90, 104]);
        assert_rgb_to_ycbcr([42, 77, 18], [60, 104, 115]);
        assert_rgb_to_ycbcr([37, 72, 6], [54, 101, 116]);
        assert_rgb_to_ycbcr([84, 140, 55], [114, 95, 107]);
        assert_rgb_to_ycbcr([46, 98, 25], [74, 100, 108]);
        assert_rgb_to_ycbcr([48, 97, 20], [74, 98, 110]);
        assert_rgb_to_ycbcr([189, 224, 156], [206, 100, 116]);
        assert_rgb_to_ycbcr([36, 83, 0], [59, 94, 111]);
        assert_rgb_to_ycbcr([159, 186, 114], [170, 97, 120]);
        assert_rgb_to_ycbcr([75, 118, 46], [97, 99, 112]);
        assert_rgb_to_ycbcr([193, 233, 158], [212, 97, 114]);
        assert_rgb_to_ycbcr([76, 116, 48], [96, 101, 114]);
        assert_rgb_to_ycbcr([108, 157, 79], [133, 97, 110]);
        assert_rgb_to_ycbcr([180, 208, 155], [194, 106, 118]);
        assert_rgb_to_ycbcr([74, 126, 53], [102, 100, 108]);
        assert_rgb_to_ycbcr([72, 123, 46], [99, 98, 109]);
        assert_rgb_to_ycbcr([71, 123, 34], [97, 92, 109]);
        assert_rgb_to_ycbcr([130, 184, 72], [155, 81, 110]);
        assert_rgb_to_ycbcr([30, 61, 17], [47, 111, 116]);
        assert_rgb_to_ycbcr([27, 71, 0], [50, 100, 112]);
        assert_rgb_to_ycbcr([45, 73, 24], [59, 108, 118]);
        assert_rgb_to_ycbcr([139, 175, 93], [155, 93, 117]);
        assert_rgb_to_ycbcr([11, 38, 0], [26, 114, 118]);
        assert_rgb_to_ycbcr([34, 87, 15], [63, 101, 107]);
        assert_rgb_to_ycbcr([43, 76, 35], [61, 113, 115]);
        assert_rgb_to_ycbcr([18, 35, 7], [27, 117, 122]);
        assert_rgb_to_ycbcr([69, 97, 48], [83, 108, 118]);
        assert_rgb_to_ycbcr([139, 176, 50], [151, 71, 120]);
        assert_rgb_to_ycbcr([21, 51, 7], [37, 111, 117]);
        assert_rgb_to_ycbcr([209, 249, 189], [230, 105, 113]);
        assert_rgb_to_ycbcr([32, 66, 14], [50, 108, 115]);
        assert_rgb_to_ycbcr([100, 143, 67], [121, 97, 113]);
        assert_rgb_to_ycbcr([40, 96, 14], [70, 96, 107]);
        assert_rgb_to_ycbcr([88, 130, 64], [110, 102, 112]);
        assert_rgb_to_ycbcr([52, 112, 14], [83, 89, 106]);
        assert_rgb_to_ycbcr([49, 72, 25], [60, 108, 120]);
        assert_rgb_to_ycbcr([144, 193, 75], [165, 77, 113]);
        assert_rgb_to_ycbcr([49, 94, 1], [70, 89, 113]);
    }
}

Coverage Report

Created: 2026-03-20 07:09

Line	Count	Source
1		#![allow(clippy::identity_op)]
2
3		use alloc::vec::Vec;
4
5		use crate::encoder::JpegColorType;
6
7		/// Conversion from RGB to YCbCr
8		#[inline]
9	0	pub fn rgb_to_ycbcr(r: u8, g: u8, b: u8) -> (u8, u8, u8) {
10		// To avoid floating point math this scales everything by 2^16 which gives
11		// a precision of approx 4 digits.
12		//
13		// Non scaled conversion:
14		// Y = 0.29900 * R + 0.58700 * G + 0.11400 * B
15		// Cb = -0.16874 * R - 0.33126 * G + 0.50000 * B + 128
16		// Cr = 0.50000 * R - 0.41869 * G - 0.08131 * B + 128
17
18	0	let r = r as i32;
19	0	let g = g as i32;
20	0	let b = b as i32;
21
22	0	let y = 19595 * r + 38470 * g + 7471 * b;
23	0	let cb = -11059 * r - 21709 * g + 32768 * b + (128 << 16);
24	0	let cr = 32768 * r - 27439 * g - 5329 * b + (128 << 16);
25
26	0	let y = (y + 0x7FFF) >> 16;
27	0	let cb = (cb + 0x7FFF) >> 16;
28	0	let cr = (cr + 0x7FFF) >> 16;
29
30	0	(y as u8, cb as u8, cr as u8)
31	0	} Unexecuted instantiation: jpeg_encoder::image_buffer::rgb_to_ycbcr Unexecuted instantiation: jpeg_encoder::image_buffer::rgb_to_ycbcr
32
33		/// Conversion from CMYK to YCCK (YCbCrK)
34		#[inline]
35	0	pub fn cmyk_to_ycck(c: u8, m: u8, y: u8, k: u8) -> (u8, u8, u8, u8) {
36	0	let (y, cb, cr) = rgb_to_ycbcr(c, m, y);
37	0	(y, cb, cr, 255 - k)
38	0	}
39
40		/// # Buffer used as input value for image encoding
41		///
42		/// Image encoding with [Encoder::encode_image](crate::Encoder::encode_image) needs an ImageBuffer
43		/// as input for the image data. For convenience the [Encoder::encode](crate::Encoder::encode)
44		/// function contains implementations for common byte based pixel formats.
45		/// Users that needs other pixel formats or don't have the data available as byte slices
46		/// can create their own buffer implementations.
47		///
48		/// ## Example: ImageBuffer implementation for RgbImage from the `image` crate
49		/// ```no_compile
50		/// use image::RgbImage;
51		/// use jpeg_encoder::{ImageBuffer, JpegColorType, rgb_to_ycbcr};
52		///
53		/// pub struct RgbImageBuffer {
54		/// image: RgbImage,
55		/// }
56		///
57		/// impl ImageBuffer for RgbImageBuffer {
58		/// fn get_jpeg_color_type(&self) -> JpegColorType {
59		/// // Rgb images are encoded as YCbCr in JFIF files
60		/// JpegColorType::Ycbcr
61		/// }
62		///
63		/// fn width(&self) -> u16 {
64		/// self.image.width() as u16
65		/// }
66		///
67		/// fn height(&self) -> u16 {
68		/// self.image.height() as u16
69		/// }
70		///
71		/// fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]){
72		/// for x in 0..self.width() {
73		/// let pixel = self.image.get_pixel(x as u32 ,y as u32);
74		///
75		/// let (y,cb,cr) = rgb_to_ycbcr(pixel[0], pixel[1], pixel[2]);
76		///
77		/// // For YCbCr the 4th buffer is not used
78		/// buffers[0].push(y);
79		/// buffers[1].push(cb);
80		/// buffers[2].push(cr);
81		/// }
82		/// }
83		/// }
84		///
85		/// ```
86		pub trait ImageBuffer {
87		/// The color type used in the image encoding
88		fn get_jpeg_color_type(&self) -> JpegColorType;
89
90		/// Width of the image
91		fn width(&self) -> u16;
92
93		/// Height of the image
94		fn height(&self) -> u16;
95
96		/// Add color values for the row to color component buffers
97		fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]);
98		}
99
100		pub(crate) struct GrayImage<'a>(pub &'a [u8], pub u16, pub u16);
101
102		impl<'a> ImageBuffer for GrayImage<'a> {
103	0	fn get_jpeg_color_type(&self) -> JpegColorType {
104	0	JpegColorType::Luma
105	0	}
106
107	0	fn width(&self) -> u16 {
108	0	self.1
109	0	}
110
111	0	fn height(&self) -> u16 {
112	0	self.2
113	0	}
114
115	0	fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
116	0	let line = get_line(self.0, y, self.width(), 1);
117
118	0	for &pixel in line {
119	0	buffers[0].push(pixel);
120	0	}
121	0	}
122		}
123
124		#[inline(always)]
125	0	fn get_line(data: &[u8], y: u16, width: u16, num_colors: usize) -> &[u8] {
126	0	let width = usize::from(width);
127	0	let y = usize::from(y);
128
129	0	let start = y * width * num_colors;
130	0	let end = start + width * num_colors;
131
132	0	&data[start..end]
133	0	}
134
135		macro_rules! ycbcr_image {
136		($name:ident, $num_colors:expr, $o1:expr, $o2:expr, $o3:expr) => {
137		pub struct $name<'a>(pub &'a [u8], pub u16, pub u16);
138
139		impl<'a> ImageBuffer for $name<'a> {
140	0	fn get_jpeg_color_type(&self) -> JpegColorType {
141	0	JpegColorType::Ycbcr
142	0	} Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbImage as jpeg_encoder::image_buffer::ImageBuffer>::get_jpeg_color_type Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbaImage as jpeg_encoder::image_buffer::ImageBuffer>::get_jpeg_color_type Unexecuted instantiation: <jpeg_encoder::image_buffer::BgrImage as jpeg_encoder::image_buffer::ImageBuffer>::get_jpeg_color_type Unexecuted instantiation: <jpeg_encoder::image_buffer::BgraImage as jpeg_encoder::image_buffer::ImageBuffer>::get_jpeg_color_type
143
144	0	fn width(&self) -> u16 {
145	0	self.1
146	0	} Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbImage as jpeg_encoder::image_buffer::ImageBuffer>::width Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbaImage as jpeg_encoder::image_buffer::ImageBuffer>::width Unexecuted instantiation: <jpeg_encoder::image_buffer::BgrImage as jpeg_encoder::image_buffer::ImageBuffer>::width Unexecuted instantiation: <jpeg_encoder::image_buffer::BgraImage as jpeg_encoder::image_buffer::ImageBuffer>::width
147
148	0	fn height(&self) -> u16 {
149	0	self.2
150	0	} Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbImage as jpeg_encoder::image_buffer::ImageBuffer>::height Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbaImage as jpeg_encoder::image_buffer::ImageBuffer>::height Unexecuted instantiation: <jpeg_encoder::image_buffer::BgrImage as jpeg_encoder::image_buffer::ImageBuffer>::height Unexecuted instantiation: <jpeg_encoder::image_buffer::BgraImage as jpeg_encoder::image_buffer::ImageBuffer>::height
151
152		#[inline(always)]
153	0	fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
154	0	let line = get_line(self.0, y, self.width(), $num_colors);
155
156		// Doing the convertion in chunks allows the compiler to vectorize the code
157		// A size of 16 seems optimal for SSE and AVX capable hardware
158		const CHUNK_SIZE: usize = 16;
159
160	0	let mut y_buffer = [0; CHUNK_SIZE];
161	0	let mut cb_buffer = [0; CHUNK_SIZE];
162	0	let mut cr_buffer = [0; CHUNK_SIZE];
163
164	0	for chuck in line.chunks_exact($num_colors * CHUNK_SIZE) {
165	0	for i in (0..CHUNK_SIZE) {
166	0	let (y, cb, cr) = rgb_to_ycbcr(
167	0	chuck[i * $num_colors + $o1],
168	0	chuck[i * $num_colors + $o2],
169	0	chuck[i * $num_colors + $o3],
170		);
171
172	0	y_buffer[i] = y;
173	0	cb_buffer[i] = cb;
174	0	cr_buffer[i] = cr;
175		}
176
177	0	buffers[0].extend_from_slice(&y_buffer);
178	0	buffers[1].extend_from_slice(&cb_buffer);
179	0	buffers[2].extend_from_slice(&cr_buffer);
180		}
181
182		// Add the remaining pixels in case the number of
183		// pixels is not a multiple of CHUNK_SIZE
184	0	let pixel = line.len() / $num_colors;
185	0	for i in pixel / CHUNK_SIZE * CHUNK_SIZE..pixel {
186	0	let (y, cb, cr) = rgb_to_ycbcr(
187	0	line[i * $num_colors + $o1],
188	0	line[i * $num_colors + $o2],
189	0	line[i * $num_colors + $o3],
190	0	);
191	0
192	0	buffers[0].push(y);
193	0	buffers[1].push(cb);
194	0	buffers[2].push(cr);
195	0	}
196	0	} Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbImage as jpeg_encoder::image_buffer::ImageBuffer>::fill_buffers Unexecuted instantiation: <jpeg_encoder::image_buffer::RgbaImage as jpeg_encoder::image_buffer::ImageBuffer>::fill_buffers Unexecuted instantiation: <jpeg_encoder::image_buffer::BgrImage as jpeg_encoder::image_buffer::ImageBuffer>::fill_buffers Unexecuted instantiation: <jpeg_encoder::image_buffer::BgraImage as jpeg_encoder::image_buffer::ImageBuffer>::fill_buffers
197		}
198		};
199		}
200
201		ycbcr_image!(RgbImage, 3, 0, 1, 2);
202		ycbcr_image!(RgbaImage, 4, 0, 1, 2);
203		ycbcr_image!(BgrImage, 3, 2, 1, 0);
204		ycbcr_image!(BgraImage, 4, 2, 1, 0);
205
206		pub(crate) struct YCbCrImage<'a>(pub &'a [u8], pub u16, pub u16);
207
208		impl<'a> ImageBuffer for YCbCrImage<'a> {
209	0	fn get_jpeg_color_type(&self) -> JpegColorType {
210	0	JpegColorType::Ycbcr
211	0	}
212
213	0	fn width(&self) -> u16 {
214	0	self.1
215	0	}
216
217	0	fn height(&self) -> u16 {
218	0	self.2
219	0	}
220
221	0	fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
222	0	let line = get_line(self.0, y, self.width(), 3);
223
224	0	for pixel in line.chunks_exact(3) {
225	0	buffers[0].push(pixel[0]);
226	0	buffers[1].push(pixel[1]);
227	0	buffers[2].push(pixel[2]);
228	0	}
229	0	}
230		}
231
232		pub(crate) struct CmykImage<'a>(pub &'a [u8], pub u16, pub u16);
233
234		impl<'a> ImageBuffer for CmykImage<'a> {
235	0	fn get_jpeg_color_type(&self) -> JpegColorType {
236	0	JpegColorType::Cmyk
237	0	}
238
239	0	fn width(&self) -> u16 {
240	0	self.1
241	0	}
242
243	0	fn height(&self) -> u16 {
244	0	self.2
245	0	}
246
247	0	fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
248	0	let line = get_line(self.0, y, self.width(), 4);
249
250	0	for pixel in line.chunks_exact(4) {
251	0	buffers[0].push(255 - pixel[0]);
252	0	buffers[1].push(255 - pixel[1]);
253	0	buffers[2].push(255 - pixel[2]);
254	0	buffers[3].push(255 - pixel[3]);
255	0	}
256	0	}
257		}
258
259		pub(crate) struct CmykAsYcckImage<'a>(pub &'a [u8], pub u16, pub u16);
260
261		impl<'a> ImageBuffer for CmykAsYcckImage<'a> {
262	0	fn get_jpeg_color_type(&self) -> JpegColorType {
263	0	JpegColorType::Ycck
264	0	}
265
266	0	fn width(&self) -> u16 {
267	0	self.1
268	0	}
269
270	0	fn height(&self) -> u16 {
271	0	self.2
272	0	}
273
274	0	fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
275	0	let line = get_line(self.0, y, self.width(), 4);
276
277	0	for pixel in line.chunks_exact(4) {
278	0	let (y, cb, cr, k) = cmyk_to_ycck(pixel[0], pixel[1], pixel[2], pixel[3]);
279	0
280	0	buffers[0].push(y);
281	0	buffers[1].push(cb);
282	0	buffers[2].push(cr);
283	0	buffers[3].push(k);
284	0	}
285	0	}
286		}
287
288		pub(crate) struct YcckImage<'a>(pub &'a [u8], pub u16, pub u16);
289
290		impl<'a> ImageBuffer for YcckImage<'a> {
291	0	fn get_jpeg_color_type(&self) -> JpegColorType {
292	0	JpegColorType::Ycck
293	0	}
294
295	0	fn width(&self) -> u16 {
296	0	self.1
297	0	}
298
299	0	fn height(&self) -> u16 {
300	0	self.2
301	0	}
302
303	0	fn fill_buffers(&self, y: u16, buffers: &mut [Vec<u8>; 4]) {
304	0	let line = get_line(self.0, y, self.width(), 4);
305
306	0	for pixel in line.chunks_exact(4) {
307	0	buffers[0].push(pixel[0]);
308	0	buffers[1].push(pixel[1]);
309	0	buffers[2].push(pixel[2]);
310	0	buffers[3].push(pixel[3]);
311	0	}
312	0	}
313		}
314
315		#[cfg(test)]
316		mod tests {
317		use crate::rgb_to_ycbcr;
318
319		fn assert_rgb_to_ycbcr(rgb: [u8; 3], ycbcr: [u8; 3]) {
320		let (y, cb, cr) = rgb_to_ycbcr(rgb[0], rgb[1], rgb[2]);
321		assert_eq!([y, cb, cr], ycbcr);
322		}
323
324		#[test]
325		fn test_rgb_to_ycbcr() {
326		assert_rgb_to_ycbcr([0, 0, 0], [0, 128, 128]);
327		assert_rgb_to_ycbcr([255, 255, 255], [255, 128, 128]);
328		assert_rgb_to_ycbcr([255, 0, 0], [76, 85, 255]);
329		assert_rgb_to_ycbcr([0, 255, 0], [150, 44, 21]);
330		assert_rgb_to_ycbcr([0, 0, 255], [29, 255, 107]);
331
332		// Values taken from libjpeg for a common image
333
334		assert_rgb_to_ycbcr([59, 109, 6], [82, 85, 111]);
335		assert_rgb_to_ycbcr([29, 60, 11], [45, 109, 116]);
336		assert_rgb_to_ycbcr([57, 114, 26], [87, 94, 107]);
337		assert_rgb_to_ycbcr([30, 60, 6], [45, 106, 117]);
338		assert_rgb_to_ycbcr([41, 75, 11], [58, 102, 116]);
339		assert_rgb_to_ycbcr([145, 184, 108], [164, 97, 115]);
340		assert_rgb_to_ycbcr([33, 85, 7], [61, 98, 108]);
341		assert_rgb_to_ycbcr([61, 90, 40], [76, 108, 118]);
342		assert_rgb_to_ycbcr([75, 127, 45], [102, 96, 109]);
343		assert_rgb_to_ycbcr([30, 56, 14], [43, 111, 118]);
344		assert_rgb_to_ycbcr([106, 142, 81], [124, 104, 115]);
345		assert_rgb_to_ycbcr([35, 59, 11], [46, 108, 120]);
346		assert_rgb_to_ycbcr([170, 203, 123], [184, 94, 118]);
347		assert_rgb_to_ycbcr([45, 87, 16], [66, 100, 113]);
348		assert_rgb_to_ycbcr([59, 109, 21], [84, 92, 110]);
349		assert_rgb_to_ycbcr([100, 167, 36], [132, 74, 105]);
350		assert_rgb_to_ycbcr([17, 53, 5], [37, 110, 114]);
351		assert_rgb_to_ycbcr([226, 244, 220], [236, 119, 121]);
352		assert_rgb_to_ycbcr([192, 214, 120], [197, 85, 125]);
353		assert_rgb_to_ycbcr([63, 107, 22], [84, 93, 113]);
354		assert_rgb_to_ycbcr([44, 78, 19], [61, 104, 116]);
355		assert_rgb_to_ycbcr([72, 106, 54], [90, 108, 115]);
356		assert_rgb_to_ycbcr([99, 123, 73], [110, 107, 120]);
357		assert_rgb_to_ycbcr([188, 216, 148], [200, 99, 120]);
358		assert_rgb_to_ycbcr([19, 46, 7], [33, 113, 118]);
359		assert_rgb_to_ycbcr([56, 95, 40], [77, 107, 113]);
360		assert_rgb_to_ycbcr([81, 120, 56], [101, 103, 114]);
361		assert_rgb_to_ycbcr([9, 30, 0], [20, 117, 120]);
362		assert_rgb_to_ycbcr([90, 118, 46], [101, 97, 120]);
363		assert_rgb_to_ycbcr([24, 52, 0], [38, 107, 118]);
364		assert_rgb_to_ycbcr([32, 69, 9], [51, 104, 114]);
365		assert_rgb_to_ycbcr([74, 134, 33], [105, 88, 106]);
366		assert_rgb_to_ycbcr([37, 74, 7], [55, 101, 115]);
367		assert_rgb_to_ycbcr([69, 119, 31], [94, 92, 110]);
368		assert_rgb_to_ycbcr([63, 112, 21], [87, 91, 111]);
369		assert_rgb_to_ycbcr([90, 148, 17], [116, 72, 110]);
370		assert_rgb_to_ycbcr([50, 97, 30], [75, 102, 110]);
371		assert_rgb_to_ycbcr([99, 129, 72], [114, 105, 118]);
372		assert_rgb_to_ycbcr([161, 196, 57], [170, 64, 122]);
373		assert_rgb_to_ycbcr([10, 26, 1], [18, 118, 122]);
374		assert_rgb_to_ycbcr([87, 128, 68], [109, 105, 112]);
375		assert_rgb_to_ycbcr([111, 155, 73], [132, 94, 113]);
376		assert_rgb_to_ycbcr([33, 75, 11], [55, 103, 112]);
377		assert_rgb_to_ycbcr([70, 122, 51], [98, 101, 108]);
378		assert_rgb_to_ycbcr([22, 74, 3], [50, 101, 108]);
379		assert_rgb_to_ycbcr([88, 142, 45], [115, 89, 109]);
380		assert_rgb_to_ycbcr([66, 107, 40], [87, 101, 113]);
381		assert_rgb_to_ycbcr([18, 45, 0], [32, 110, 118]);
382		assert_rgb_to_ycbcr([163, 186, 88], [168, 83, 124]);
383		assert_rgb_to_ycbcr([47, 104, 4], [76, 88, 108]);
384		assert_rgb_to_ycbcr([147, 211, 114], [181, 90, 104]);
385		assert_rgb_to_ycbcr([42, 77, 18], [60, 104, 115]);
386		assert_rgb_to_ycbcr([37, 72, 6], [54, 101, 116]);
387		assert_rgb_to_ycbcr([84, 140, 55], [114, 95, 107]);
388		assert_rgb_to_ycbcr([46, 98, 25], [74, 100, 108]);
389		assert_rgb_to_ycbcr([48, 97, 20], [74, 98, 110]);
390		assert_rgb_to_ycbcr([189, 224, 156], [206, 100, 116]);
391		assert_rgb_to_ycbcr([36, 83, 0], [59, 94, 111]);
392		assert_rgb_to_ycbcr([159, 186, 114], [170, 97, 120]);
393		assert_rgb_to_ycbcr([75, 118, 46], [97, 99, 112]);
394		assert_rgb_to_ycbcr([193, 233, 158], [212, 97, 114]);
395		assert_rgb_to_ycbcr([76, 116, 48], [96, 101, 114]);
396		assert_rgb_to_ycbcr([108, 157, 79], [133, 97, 110]);
397		assert_rgb_to_ycbcr([180, 208, 155], [194, 106, 118]);
398		assert_rgb_to_ycbcr([74, 126, 53], [102, 100, 108]);
399		assert_rgb_to_ycbcr([72, 123, 46], [99, 98, 109]);
400		assert_rgb_to_ycbcr([71, 123, 34], [97, 92, 109]);
401		assert_rgb_to_ycbcr([130, 184, 72], [155, 81, 110]);
402		assert_rgb_to_ycbcr([30, 61, 17], [47, 111, 116]);
403		assert_rgb_to_ycbcr([27, 71, 0], [50, 100, 112]);
404		assert_rgb_to_ycbcr([45, 73, 24], [59, 108, 118]);
405		assert_rgb_to_ycbcr([139, 175, 93], [155, 93, 117]);
406		assert_rgb_to_ycbcr([11, 38, 0], [26, 114, 118]);
407		assert_rgb_to_ycbcr([34, 87, 15], [63, 101, 107]);
408		assert_rgb_to_ycbcr([43, 76, 35], [61, 113, 115]);
409		assert_rgb_to_ycbcr([18, 35, 7], [27, 117, 122]);
410		assert_rgb_to_ycbcr([69, 97, 48], [83, 108, 118]);
411		assert_rgb_to_ycbcr([139, 176, 50], [151, 71, 120]);
412		assert_rgb_to_ycbcr([21, 51, 7], [37, 111, 117]);
413		assert_rgb_to_ycbcr([209, 249, 189], [230, 105, 113]);
414		assert_rgb_to_ycbcr([32, 66, 14], [50, 108, 115]);
415		assert_rgb_to_ycbcr([100, 143, 67], [121, 97, 113]);
416		assert_rgb_to_ycbcr([40, 96, 14], [70, 96, 107]);
417		assert_rgb_to_ycbcr([88, 130, 64], [110, 102, 112]);
418		assert_rgb_to_ycbcr([52, 112, 14], [83, 89, 106]);
419		assert_rgb_to_ycbcr([49, 72, 25], [60, 108, 120]);
420		assert_rgb_to_ycbcr([144, 193, 75], [165, 77, 113]);
421		assert_rgb_to_ycbcr([49, 94, 1], [70, 89, 113]);
422		}
423		}