From 1b6a04ca5504955c571d1c97504fb45ea0befee4 Mon Sep 17 00:00:00 2001 From: Valentin Popov Date: Mon, 8 Jan 2024 01:21:28 +0400 Subject: Initial vendor packages Signed-off-by: Valentin Popov --- vendor/image/src/codecs/webp/lossless_transform.rs | 464 +++++++++++++++++++++ 1 file changed, 464 insertions(+) create mode 100644 vendor/image/src/codecs/webp/lossless_transform.rs (limited to 'vendor/image/src/codecs/webp/lossless_transform.rs') diff --git a/vendor/image/src/codecs/webp/lossless_transform.rs b/vendor/image/src/codecs/webp/lossless_transform.rs new file mode 100644 index 0000000..f9a82c1 --- /dev/null +++ b/vendor/image/src/codecs/webp/lossless_transform.rs @@ -0,0 +1,464 @@ +use std::convert::TryFrom; +use std::convert::TryInto; + +use super::lossless::subsample_size; +use super::lossless::DecoderError; + +#[derive(Debug, Clone)] +pub(crate) enum TransformType { + PredictorTransform { + size_bits: u8, + predictor_data: Vec, + }, + ColorTransform { + size_bits: u8, + transform_data: Vec, + }, + SubtractGreen, + ColorIndexingTransform { + table_size: u16, + table_data: Vec, + }, +} + +impl TransformType { + /// Applies a transform to the image data + pub(crate) fn apply_transform( + &self, + image_data: &mut Vec, + width: u16, + height: u16, + ) -> Result<(), DecoderError> { + match self { + TransformType::PredictorTransform { + size_bits, + predictor_data, + } => { + let block_xsize = usize::from(subsample_size(width, *size_bits)); + let width = usize::from(width); + let height = usize::from(height); + + if image_data.len() < width * height { + return Err(DecoderError::TransformError); + } + + //handle top and left borders specially + //this involves ignoring mode and just setting prediction values like this + image_data[0] = add_pixels(image_data[0], 0xff000000); + + for x in 1..width { + image_data[x] = add_pixels(image_data[x], get_left(image_data, x, 0, width)); + } + + for y in 1..height { + image_data[y * width] = + add_pixels(image_data[y * width], get_top(image_data, 0, y, width)); + } + + for y in 1..height { + for x in 1..width { + let block_index = (y >> size_bits) * block_xsize + (x >> size_bits); + + let index = y * width + x; + + let green = (predictor_data[block_index] >> 8) & 0xff; + + match green { + 0 => image_data[index] = add_pixels(image_data[index], 0xff000000), + 1 => { + image_data[index] = + add_pixels(image_data[index], get_left(image_data, x, y, width)) + } + 2 => { + image_data[index] = + add_pixels(image_data[index], get_top(image_data, x, y, width)) + } + 3 => { + image_data[index] = add_pixels( + image_data[index], + get_top_right(image_data, x, y, width), + ) + } + 4 => { + image_data[index] = add_pixels( + image_data[index], + get_top_left(image_data, x, y, width), + ) + } + 5 => { + image_data[index] = add_pixels(image_data[index], { + let first = average2( + get_left(image_data, x, y, width), + get_top_right(image_data, x, y, width), + ); + average2(first, get_top(image_data, x, y, width)) + }) + } + 6 => { + image_data[index] = add_pixels( + image_data[index], + average2( + get_left(image_data, x, y, width), + get_top_left(image_data, x, y, width), + ), + ) + } + 7 => { + image_data[index] = add_pixels( + image_data[index], + average2( + get_left(image_data, x, y, width), + get_top(image_data, x, y, width), + ), + ) + } + 8 => { + image_data[index] = add_pixels( + image_data[index], + average2( + get_top_left(image_data, x, y, width), + get_top(image_data, x, y, width), + ), + ) + } + 9 => { + image_data[index] = add_pixels( + image_data[index], + average2( + get_top(image_data, x, y, width), + get_top_right(image_data, x, y, width), + ), + ) + } + 10 => { + image_data[index] = add_pixels(image_data[index], { + let first = average2( + get_left(image_data, x, y, width), + get_top_left(image_data, x, y, width), + ); + let second = average2( + get_top(image_data, x, y, width), + get_top_right(image_data, x, y, width), + ); + average2(first, second) + }) + } + 11 => { + image_data[index] = add_pixels( + image_data[index], + select( + get_left(image_data, x, y, width), + get_top(image_data, x, y, width), + get_top_left(image_data, x, y, width), + ), + ) + } + 12 => { + image_data[index] = add_pixels( + image_data[index], + clamp_add_subtract_full( + get_left(image_data, x, y, width), + get_top(image_data, x, y, width), + get_top_left(image_data, x, y, width), + ), + ) + } + 13 => { + image_data[index] = add_pixels(image_data[index], { + let first = average2( + get_left(image_data, x, y, width), + get_top(image_data, x, y, width), + ); + clamp_add_subtract_half( + first, + get_top_left(image_data, x, y, width), + ) + }) + } + _ => {} + } + } + } + } + TransformType::ColorTransform { + size_bits, + transform_data, + } => { + let block_xsize = usize::from(subsample_size(width, *size_bits)); + let width = usize::from(width); + let height = usize::from(height); + + for y in 0..height { + for x in 0..width { + let block_index = (y >> size_bits) * block_xsize + (x >> size_bits); + + let index = y * width + x; + + let multiplier = + ColorTransformElement::from_color_code(transform_data[block_index]); + + image_data[index] = transform_color(&multiplier, image_data[index]); + } + } + } + TransformType::SubtractGreen => { + let width = usize::from(width); + for y in 0..usize::from(height) { + for x in 0..width { + image_data[y * width + x] = add_green(image_data[y * width + x]); + } + } + } + TransformType::ColorIndexingTransform { + table_size, + table_data, + } => { + let mut new_image_data = + Vec::with_capacity(usize::from(width) * usize::from(height)); + + let table_size = *table_size; + let width_bits: u8 = if table_size <= 2 { + 3 + } else if table_size <= 4 { + 2 + } else if table_size <= 16 { + 1 + } else { + 0 + }; + + let bits_per_pixel = 8 >> width_bits; + let mask = (1 << bits_per_pixel) - 1; + + let mut src = 0; + let width = usize::from(width); + + let pixels_per_byte = 1 << width_bits; + let count_mask = pixels_per_byte - 1; + let mut packed_pixels = 0; + + for _y in 0..usize::from(height) { + for x in 0..width { + if (x & count_mask) == 0 { + packed_pixels = (image_data[src] >> 8) & 0xff; + src += 1; + } + + let pixels: usize = (packed_pixels & mask).try_into().unwrap(); + let new_val = if pixels >= table_size.into() { + 0x00000000 + } else { + table_data[pixels] + }; + + new_image_data.push(new_val); + + packed_pixels >>= bits_per_pixel; + } + } + + *image_data = new_image_data; + } + } + + Ok(()) + } +} + +//predictor functions + +/// Adds 2 pixels mod 256 for each pixel +pub(crate) fn add_pixels(a: u32, b: u32) -> u32 { + let new_alpha = ((a >> 24) + (b >> 24)) & 0xff; + let new_red = (((a >> 16) & 0xff) + ((b >> 16) & 0xff)) & 0xff; + let new_green = (((a >> 8) & 0xff) + ((b >> 8) & 0xff)) & 0xff; + let new_blue = ((a & 0xff) + (b & 0xff)) & 0xff; + + (new_alpha << 24) + (new_red << 16) + (new_green << 8) + new_blue +} + +/// Get left pixel +fn get_left(data: &[u32], x: usize, y: usize, width: usize) -> u32 { + data[y * width + x - 1] +} + +/// Get top pixel +fn get_top(data: &[u32], x: usize, y: usize, width: usize) -> u32 { + data[(y - 1) * width + x] +} + +/// Get pixel to top right +fn get_top_right(data: &[u32], x: usize, y: usize, width: usize) -> u32 { + // if x == width - 1 this gets the left most pixel of the current row + // as described in the specification + data[(y - 1) * width + x + 1] +} + +/// Get pixel to top left +fn get_top_left(data: &[u32], x: usize, y: usize, width: usize) -> u32 { + data[(y - 1) * width + x - 1] +} + +/// Get average of 2 pixels +fn average2(a: u32, b: u32) -> u32 { + let mut avg = 0u32; + for i in 0..4 { + let sub_a: u8 = ((a >> (i * 8)) & 0xff).try_into().unwrap(); + let sub_b: u8 = ((b >> (i * 8)) & 0xff).try_into().unwrap(); + avg |= u32::from(sub_average2(sub_a, sub_b)) << (i * 8); + } + avg +} + +/// Get average of 2 bytes +fn sub_average2(a: u8, b: u8) -> u8 { + ((u16::from(a) + u16::from(b)) / 2).try_into().unwrap() +} + +/// Get a specific byte from argb pixel +fn get_byte(val: u32, byte: u8) -> u8 { + ((val >> (byte * 8)) & 0xff).try_into().unwrap() +} + +/// Get byte as i32 for convenience +fn get_byte_i32(val: u32, byte: u8) -> i32 { + i32::from(get_byte(val, byte)) +} + +/// Select left or top byte +fn select(left: u32, top: u32, top_left: u32) -> u32 { + let predict_alpha = get_byte_i32(left, 3) + get_byte_i32(top, 3) - get_byte_i32(top_left, 3); + let predict_red = get_byte_i32(left, 2) + get_byte_i32(top, 2) - get_byte_i32(top_left, 2); + let predict_green = get_byte_i32(left, 1) + get_byte_i32(top, 1) - get_byte_i32(top_left, 1); + let predict_blue = get_byte_i32(left, 0) + get_byte_i32(top, 0) - get_byte_i32(top_left, 0); + + let predict_left = i32::abs(predict_alpha - get_byte_i32(left, 3)) + + i32::abs(predict_red - get_byte_i32(left, 2)) + + i32::abs(predict_green - get_byte_i32(left, 1)) + + i32::abs(predict_blue - get_byte_i32(left, 0)); + let predict_top = i32::abs(predict_alpha - get_byte_i32(top, 3)) + + i32::abs(predict_red - get_byte_i32(top, 2)) + + i32::abs(predict_green - get_byte_i32(top, 1)) + + i32::abs(predict_blue - get_byte_i32(top, 0)); + + if predict_left < predict_top { + left + } else { + top + } +} + +/// Clamp a to [0, 255] +fn clamp(a: i32) -> i32 { + if a < 0 { + 0 + } else if a > 255 { + 255 + } else { + a + } +} + +/// Clamp add subtract full on one part +fn clamp_add_subtract_full_sub(a: i32, b: i32, c: i32) -> i32 { + clamp(a + b - c) +} + +/// Clamp add subtract half on one part +fn clamp_add_subtract_half_sub(a: i32, b: i32) -> i32 { + clamp(a + (a - b) / 2) +} + +/// Clamp add subtract full on 3 pixels +fn clamp_add_subtract_full(a: u32, b: u32, c: u32) -> u32 { + let mut value: u32 = 0; + for i in 0..4u8 { + let sub_a: i32 = ((a >> (i * 8)) & 0xff).try_into().unwrap(); + let sub_b: i32 = ((b >> (i * 8)) & 0xff).try_into().unwrap(); + let sub_c: i32 = ((c >> (i * 8)) & 0xff).try_into().unwrap(); + value |= + u32::try_from(clamp_add_subtract_full_sub(sub_a, sub_b, sub_c)).unwrap() << (i * 8); + } + value +} + +/// Clamp add subtract half on 2 pixels +fn clamp_add_subtract_half(a: u32, b: u32) -> u32 { + let mut value = 0; + for i in 0..4u8 { + let sub_a: i32 = ((a >> (i * 8)) & 0xff).try_into().unwrap(); + let sub_b: i32 = ((b >> (i * 8)) & 0xff).try_into().unwrap(); + value |= u32::try_from(clamp_add_subtract_half_sub(sub_a, sub_b)).unwrap() << (i * 8); + } + + value +} + +//color transform + +#[derive(Debug, Clone, Copy)] +struct ColorTransformElement { + green_to_red: u8, + green_to_blue: u8, + red_to_blue: u8, +} + +impl ColorTransformElement { + fn from_color_code(color_code: u32) -> ColorTransformElement { + ColorTransformElement { + green_to_red: (color_code & 0xff).try_into().unwrap(), + green_to_blue: ((color_code >> 8) & 0xff).try_into().unwrap(), + red_to_blue: ((color_code >> 16) & 0xff).try_into().unwrap(), + } + } +} + +/// Does color transform on red and blue transformed by green +fn color_transform(red: u8, blue: u8, green: u8, trans: &ColorTransformElement) -> (u8, u8) { + let mut temp_red = u32::from(red); + let mut temp_blue = u32::from(blue); + + //as does the conversion from u8 to signed two's complement i8 required + temp_red += color_transform_delta(trans.green_to_red as i8, green as i8); + temp_blue += color_transform_delta(trans.green_to_blue as i8, green as i8); + temp_blue += color_transform_delta(trans.red_to_blue as i8, temp_red as i8); + + ( + (temp_red & 0xff).try_into().unwrap(), + (temp_blue & 0xff).try_into().unwrap(), + ) +} + +/// Does color transform on 2 numbers +fn color_transform_delta(t: i8, c: i8) -> u32 { + ((i16::from(t) * i16::from(c)) as u32) >> 5 +} + +// Does color transform on a pixel with a color transform element +fn transform_color(multiplier: &ColorTransformElement, color_value: u32) -> u32 { + let alpha = get_byte(color_value, 3); + let red = get_byte(color_value, 2); + let green = get_byte(color_value, 1); + let blue = get_byte(color_value, 0); + + let (new_red, new_blue) = color_transform(red, blue, green, multiplier); + + (u32::from(alpha) << 24) + + (u32::from(new_red) << 16) + + (u32::from(green) << 8) + + u32::from(new_blue) +} + +//subtract green function + +/// Adds green to red and blue of a pixel +fn add_green(argb: u32) -> u32 { + let red = (argb >> 16) & 0xff; + let green = (argb >> 8) & 0xff; + let blue = argb & 0xff; + + let new_red = (red + green) & 0xff; + let new_blue = (blue + green) & 0xff; + + (argb & 0xff00ff00) | (new_red << 16) | (new_blue) +} -- cgit v1.2.3