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authorValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
committerValentin Popov <valentin@popov.link>2024-07-19 15:37:58 +0300
commita990de90fe41456a23e58bd087d2f107d321f3a1 (patch)
tree15afc392522a9e85dc3332235e311b7d39352ea9 /vendor/exr/src/compression/pxr24.rs
parent3d48cd3f81164bbfc1a755dc1d4a9a02f98c8ddd (diff)
downloadfparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.tar.xz
fparkan-a990de90fe41456a23e58bd087d2f107d321f3a1.zip
Deleted vendor folder
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-rw-r--r--vendor/exr/src/compression/pxr24.rs261
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diff --git a/vendor/exr/src/compression/pxr24.rs b/vendor/exr/src/compression/pxr24.rs
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-
-//! Lossy compression for F32 data, but lossless compression for U32 and F16 data.
-// see https://github.com/AcademySoftwareFoundation/openexr/blob/master/OpenEXR/IlmImf/ImfPxr24Compressor.cpp
-
-// This compressor is based on source code that was contributed to
-// OpenEXR by Pixar Animation Studios. The compression method was
-// developed by Loren Carpenter.
-
-
-// The compressor preprocesses the pixel data to reduce entropy, and then calls zlib.
-// Compression of HALF and UINT channels is lossless, but compressing
-// FLOAT channels is lossy: 32-bit floating-point numbers are converted
-// to 24 bits by rounding the significand to 15 bits.
-//
-// When the compressor is invoked, the caller has already arranged
-// the pixel data so that the values for each channel appear in a
-// contiguous block of memory. The compressor converts the pixel
-// values to unsigned integers: For UINT, this is a no-op. HALF
-// values are simply re-interpreted as 16-bit integers. FLOAT
-// values are converted to 24 bits, and the resulting bit patterns
-// are interpreted as integers. The compressor then replaces each
-// value with the difference between the value and its left neighbor.
-// This turns flat fields in the image into zeroes, and ramps into
-// strings of similar values. Next, each difference is split into
-// 2, 3 or 4 bytes, and the bytes are transposed so that all the
-// most significant bytes end up in a contiguous block, followed
-// by the second most significant bytes, and so on. The resulting
-// string of bytes is compressed with zlib.
-
-use super::*;
-
-use crate::error::Result;
-use lebe::io::ReadPrimitive;
-
-
-// scanline decompression routine, see https://github.com/openexr/openexr/blob/master/OpenEXR/IlmImf/ImfScanLineInputFile.cpp
-// 1. Uncompress the data, if necessary (If the line is uncompressed, it's in XDR format, regardless of the compressor's output format.)
-// 3. Convert one scan line's worth of pixel data back from the machine-independent representation
-// 4. Fill the frame buffer with pixel data, respective to sampling and whatnot
-
-
-#[cfg_attr(target_endian = "big", allow(unused, unreachable_code))]
-pub fn compress(channels: &ChannelList, remaining_bytes: ByteVec, area: IntegerBounds) -> Result<ByteVec> {
- #[cfg(target_endian = "big")] {
- return Err(Error::unsupported(
- "PXR24 compression method not supported yet on big endian processor architecture"
- ))
- }
-
- if remaining_bytes.is_empty() { return Ok(Vec::new()); }
-
- // see https://github.com/AcademySoftwareFoundation/openexr/blob/3bd93f85bcb74c77255f28cdbb913fdbfbb39dfe/OpenEXR/IlmImf/ImfTiledOutputFile.cpp#L750-L842
- let remaining_bytes = super::convert_current_to_little_endian(remaining_bytes, channels, area);
- let mut remaining_bytes = remaining_bytes.as_slice(); // TODO less allocation
-
- let bytes_per_pixel: usize = channels.list.iter()
- .map(|channel| match channel.sample_type {
- SampleType::F16 => 2, SampleType::F32 => 3, SampleType::U32 => 4,
- })
- .sum();
-
- let mut raw = vec![0_u8; bytes_per_pixel * area.size.area()];
-
- {
- let mut write = raw.as_mut_slice();
-
- // TODO this loop should be an iterator in the `IntegerBounds` class, as it is used in all compressio methods
- for y in area.position.1..area.end().1 {
- for channel in &channels.list {
- if mod_p(y, usize_to_i32(channel.sampling.1)) != 0 { continue; }
-
- // this apparently can't be a closure in Rust 1.43 due to borrowing ambiguity
- let sample_count_x = channel.subsampled_resolution(area.size).0;
- macro_rules! split_off_write_slice { () => {{
- let (slice, rest) = write.split_at_mut(sample_count_x);
- write = rest;
- slice
- }}; }
-
- let mut previous_pixel: u32 = 0;
-
- match channel.sample_type {
- SampleType::F16 => {
- let out_byte_tuples = split_off_write_slice!().iter_mut()
- .zip(split_off_write_slice!());
-
- for (out_byte_0, out_byte_1) in out_byte_tuples {
- let pixel = u16::read_from_native_endian(&mut remaining_bytes).unwrap() as u32;
- let [byte_1, byte_0] = (pixel.wrapping_sub(previous_pixel) as u16).to_ne_bytes();
-
- *out_byte_0 = byte_0;
- *out_byte_1 = byte_1;
- previous_pixel = pixel;
- }
- },
-
- SampleType::U32 => {
- let out_byte_quadruplets = split_off_write_slice!().iter_mut()
- .zip(split_off_write_slice!())
- .zip(split_off_write_slice!())
- .zip(split_off_write_slice!());
-
- for (((out_byte_0, out_byte_1), out_byte_2), out_byte_3) in out_byte_quadruplets {
- let pixel = u32::read_from_native_endian(&mut remaining_bytes).unwrap();
- let [byte_3, byte_2, byte_1, byte_0] = pixel.wrapping_sub(previous_pixel).to_ne_bytes();
-
- *out_byte_0 = byte_0;
- *out_byte_1 = byte_1;
- *out_byte_2 = byte_2;
- *out_byte_3 = byte_3;
- previous_pixel = pixel;
- }
- },
-
- SampleType::F32 => {
- let out_byte_triplets = split_off_write_slice!().iter_mut()
- .zip(split_off_write_slice!())
- .zip(split_off_write_slice!());
-
- for ((out_byte_0, out_byte_1), out_byte_2) in out_byte_triplets {
- let pixel = f32_to_f24(f32::read_from_native_endian(&mut remaining_bytes).unwrap());
- let [byte_2, byte_1, byte_0, _] = pixel.wrapping_sub(previous_pixel).to_ne_bytes();
- previous_pixel = pixel;
-
- *out_byte_0 = byte_0;
- *out_byte_1 = byte_1;
- *out_byte_2 = byte_2;
- }
- },
- }
- }
- }
-
- debug_assert_eq!(write.len(), 0, "bytes left after compression");
- }
-
- Ok(miniz_oxide::deflate::compress_to_vec_zlib(raw.as_slice(), 4))
-}
-
-#[cfg_attr(target_endian = "big", allow(unused, unreachable_code))]
-pub fn decompress(channels: &ChannelList, bytes: ByteVec, area: IntegerBounds, expected_byte_size: usize, pedantic: bool) -> Result<ByteVec> {
- #[cfg(target_endian = "big")] {
- return Err(Error::unsupported(
- "PXR24 decompression method not supported yet on big endian processor architecture"
- ))
- }
-
- let options = zune_inflate::DeflateOptions::default().set_limit(expected_byte_size).set_size_hint(expected_byte_size);
- let mut decoder = zune_inflate::DeflateDecoder::new_with_options(&bytes, options);
- let raw = decoder.decode_zlib()
- .map_err(|_| Error::invalid("zlib-compressed data malformed"))?; // TODO share code with zip?
-
- let mut read = raw.as_slice();
- let mut out = Vec::with_capacity(expected_byte_size.min(2048*4));
-
- for y in area.position.1 .. area.end().1 {
- for channel in &channels.list {
- if mod_p(y, usize_to_i32(channel.sampling.1)) != 0 { continue; }
-
- let sample_count_x = channel.subsampled_resolution(area.size).0;
- let mut read_sample_line = ||{
- if sample_count_x > read.len() { return Err(Error::invalid("not enough data")) }
- let (samples, rest) = read.split_at(sample_count_x);
- read = rest;
- Ok(samples)
- };
-
- let mut pixel_accumulation: u32 = 0;
-
- match channel.sample_type {
- SampleType::F16 => {
- let sample_byte_pairs = read_sample_line()?.iter()
- .zip(read_sample_line()?);
-
- for (&in_byte_0, &in_byte_1) in sample_byte_pairs {
- let difference = u16::from_ne_bytes([in_byte_1, in_byte_0]) as u32;
- pixel_accumulation = pixel_accumulation.overflowing_add(difference).0;
- out.extend_from_slice(&(pixel_accumulation as u16).to_ne_bytes());
- }
- },
-
- SampleType::U32 => {
- let sample_byte_quads = read_sample_line()?.iter()
- .zip(read_sample_line()?)
- .zip(read_sample_line()?)
- .zip(read_sample_line()?);
-
- for (((&in_byte_0, &in_byte_1), &in_byte_2), &in_byte_3) in sample_byte_quads {
- let difference = u32::from_ne_bytes([in_byte_3, in_byte_2, in_byte_1, in_byte_0]);
- pixel_accumulation = pixel_accumulation.overflowing_add(difference).0;
- out.extend_from_slice(&pixel_accumulation.to_ne_bytes());
- }
- },
-
- SampleType::F32 => {
- let sample_byte_triplets = read_sample_line()?.iter()
- .zip(read_sample_line()?).zip(read_sample_line()?);
-
- for ((&in_byte_0, &in_byte_1), &in_byte_2) in sample_byte_triplets {
- let difference = u32::from_ne_bytes([0, in_byte_2, in_byte_1, in_byte_0]);
- pixel_accumulation = pixel_accumulation.overflowing_add(difference).0;
- out.extend_from_slice(&pixel_accumulation.to_ne_bytes());
- }
- }
- }
- }
- }
-
- if pedantic && !read.is_empty() {
- return Err(Error::invalid("too much data"));
- }
-
- Ok(super::convert_little_endian_to_current(out, channels, area))
-}
-
-
-
-
-/// Conversion from 32-bit to 24-bit floating-point numbers.
-/// Reverse conversion is just a simple 8-bit left shift.
-pub fn f32_to_f24(float: f32) -> u32 {
- let bits = float.to_bits();
-
- let sign = bits & 0x80000000;
- let exponent = bits & 0x7f800000;
- let mantissa = bits & 0x007fffff;
-
- let result = if exponent == 0x7f800000 {
- if mantissa != 0 {
- // F is a NAN; we preserve the sign bit and
- // the 15 leftmost bits of the significand,
- // with one exception: If the 15 leftmost
- // bits are all zero, the NAN would turn
- // into an infinity, so we have to set at
- // least one bit in the significand.
-
- let mantissa = mantissa >> 8;
- (exponent >> 8) | mantissa | if mantissa == 0 { 1 } else { 0 }
- }
- else { // F is an infinity.
- exponent >> 8
- }
- }
- else { // F is finite, round the significand to 15 bits.
- let result = ((exponent | mantissa) + (mantissa & 0x00000080)) >> 8;
-
- if result >= 0x7f8000 {
- // F was close to FLT_MAX, and the significand was
- // rounded up, resulting in an exponent overflow.
- // Avoid the overflow by truncating the significand
- // instead of rounding it.
-
- (exponent | mantissa) >> 8
- }
- else {
- result
- }
- };
-
- return (sign >> 8) | result;
-} \ No newline at end of file