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-rw-r--r--vendor/image/src/utils/mod.rs128
1 files changed, 0 insertions, 128 deletions
diff --git a/vendor/image/src/utils/mod.rs b/vendor/image/src/utils/mod.rs
deleted file mode 100644
index 529c60f..0000000
--- a/vendor/image/src/utils/mod.rs
+++ /dev/null
@@ -1,128 +0,0 @@
-//! Utilities
-
-use std::iter::repeat;
-
-#[inline(always)]
-pub(crate) fn expand_packed<F>(buf: &mut [u8], channels: usize, bit_depth: u8, mut func: F)
-where
- F: FnMut(u8, &mut [u8]),
-{
- let pixels = buf.len() / channels * bit_depth as usize;
- let extra = pixels % 8;
- let entries = pixels / 8
- + match extra {
- 0 => 0,
- _ => 1,
- };
- let mask = ((1u16 << bit_depth) - 1) as u8;
- let i = (0..entries)
- .rev() // Reverse iterator
- .flat_map(|idx|
- // This has to be reversed to
- (0..8/bit_depth).map(|i| i*bit_depth).zip(repeat(idx)))
- .skip(extra);
- let buf_len = buf.len();
- let j_inv = (channels..buf_len).step_by(channels);
- for ((shift, i), j_inv) in i.zip(j_inv) {
- let j = buf_len - j_inv;
- let pixel = (buf[i] & (mask << shift)) >> shift;
- func(pixel, &mut buf[j..(j + channels)])
- }
-}
-
-/// Expand a buffer of packed 1, 2, or 4 bits integers into u8's. Assumes that
-/// every `row_size` entries there are padding bits up to the next byte boundary.
-#[allow(dead_code)]
-// When no image formats that use it are enabled
-pub(crate) fn expand_bits(bit_depth: u8, row_size: u32, buf: &[u8]) -> Vec<u8> {
- // Note: this conversion assumes that the scanlines begin on byte boundaries
- let mask = (1u8 << bit_depth as usize) - 1;
- let scaling_factor = 255 / ((1 << bit_depth as usize) - 1);
- let bit_width = row_size * u32::from(bit_depth);
- let skip = if bit_width % 8 == 0 {
- 0
- } else {
- (8 - bit_width % 8) / u32::from(bit_depth)
- };
- let row_len = row_size + skip;
- let mut p = Vec::new();
- let mut i = 0;
- for v in buf {
- for shift_inv in 1..=8 / bit_depth {
- let shift = 8 - bit_depth * shift_inv;
- // skip the pixels that can be neglected because scanlines should
- // start at byte boundaries
- if i % (row_len as usize) < (row_size as usize) {
- let pixel = (v & mask << shift as usize) >> shift as usize;
- p.push(pixel * scaling_factor);
- }
- i += 1;
- }
- }
- p
-}
-
-/// Checks if the provided dimensions would cause an overflow.
-#[allow(dead_code)]
-// When no image formats that use it are enabled
-pub(crate) fn check_dimension_overflow(width: u32, height: u32, bytes_per_pixel: u8) -> bool {
- width as u64 * height as u64 > std::u64::MAX / bytes_per_pixel as u64
-}
-
-#[allow(dead_code)]
-// When no image formats that use it are enabled
-pub(crate) fn vec_copy_to_u8<T>(vec: &[T]) -> Vec<u8>
-where
- T: bytemuck::Pod,
-{
- bytemuck::cast_slice(vec).to_owned()
-}
-
-#[inline]
-pub(crate) fn clamp<N>(a: N, min: N, max: N) -> N
-where
- N: PartialOrd,
-{
- if a < min {
- min
- } else if a > max {
- max
- } else {
- a
- }
-}
-
-#[cfg(test)]
-mod test {
- #[test]
- fn gray_to_luma8_skip() {
- let check = |bit_depth, w, from, to| {
- assert_eq!(super::expand_bits(bit_depth, w, from), to);
- };
- // Bit depth 1, skip is more than half a byte
- check(
- 1,
- 10,
- &[0b11110000, 0b11000000, 0b00001111, 0b11000000],
- vec![
- 255, 255, 255, 255, 0, 0, 0, 0, 255, 255, 0, 0, 0, 0, 255, 255, 255, 255, 255, 255,
- ],
- );
- // Bit depth 2, skip is more than half a byte
- check(
- 2,
- 5,
- &[0b11110000, 0b11000000, 0b00001111, 0b11000000],
- vec![255, 255, 0, 0, 255, 0, 0, 255, 255, 255],
- );
- // Bit depth 2, skip is 0
- check(
- 2,
- 4,
- &[0b11110000, 0b00001111],
- vec![255, 255, 0, 0, 0, 0, 255, 255],
- );
- // Bit depth 4, skip is half a byte
- check(4, 1, &[0b11110011, 0b00001100], vec![255, 0]);
- }
-}