From a990de90fe41456a23e58bd087d2f107d321f3a1 Mon Sep 17 00:00:00 2001 From: Valentin Popov Date: Fri, 19 Jul 2024 16:37:58 +0400 Subject: Deleted vendor folder --- vendor/exr/src/compression/piz/huffman.rs | 988 ------------------------------ 1 file changed, 988 deletions(-) delete mode 100644 vendor/exr/src/compression/piz/huffman.rs (limited to 'vendor/exr/src/compression/piz/huffman.rs') diff --git a/vendor/exr/src/compression/piz/huffman.rs b/vendor/exr/src/compression/piz/huffman.rs deleted file mode 100644 index a01cbf2..0000000 --- a/vendor/exr/src/compression/piz/huffman.rs +++ /dev/null @@ -1,988 +0,0 @@ -//! 16-bit Huffman compression and decompression. -//! Huffman compression and decompression routines written -//! by Christian Rouet for his PIZ image file format. -// see https://github.com/AcademySoftwareFoundation/openexr/blob/88246d991e0318c043e6f584f7493da08a31f9f8/OpenEXR/IlmImf/ImfHuf.cpp - -use crate::math::RoundingMode; -use crate::error::{Error, Result, UnitResult, u64_to_usize, u32_to_usize}; -use crate::io::Data; -use std::{ - cmp::Ordering, - collections::BinaryHeap, - io::{Cursor, Read, Write}, -}; -use std::convert::TryFrom; -use smallvec::SmallVec; - - -pub fn decompress(compressed: &[u8], expected_size: usize) -> Result> { - let mut remaining_compressed = compressed; - - let min_code_index = usize::try_from(u32::read(&mut remaining_compressed)?)?; - let max_code_index_32 = u32::read(&mut remaining_compressed)?; - let _table_size = usize::try_from(u32::read(&mut remaining_compressed)?)?; // TODO check this and return Err? - let bit_count = usize::try_from(u32::read(&mut remaining_compressed)?)?; - let _skipped = u32::read(&mut remaining_compressed)?; // what is this - - let max_code_index = usize::try_from(max_code_index_32).unwrap(); - if min_code_index >= ENCODING_TABLE_SIZE || max_code_index >= ENCODING_TABLE_SIZE { - return Err(Error::invalid(INVALID_TABLE_SIZE)); - } - - if RoundingMode::Up.divide(bit_count, 8) > remaining_compressed.len() { - return Err(Error::invalid(NOT_ENOUGH_DATA)); - } - - let encoding_table = read_encoding_table(&mut remaining_compressed, min_code_index, max_code_index)?; - if bit_count > 8 * remaining_compressed.len() { return Err(Error::invalid(INVALID_BIT_COUNT)); } - - let decoding_table = build_decoding_table(&encoding_table, min_code_index, max_code_index)?; - - let result = decode_with_tables( - &encoding_table, - &decoding_table, - &remaining_compressed, - i32::try_from(bit_count)?, - max_code_index_32, - expected_size, - )?; - - Ok(result) -} - -pub fn compress(uncompressed: &[u16]) -> Result> { - if uncompressed.is_empty() { return Ok(vec![]); } - - let mut frequencies = count_frequencies(uncompressed); - let (min_code_index, max_code_index) = build_encoding_table(&mut frequencies); - - let mut result = Cursor::new(Vec::with_capacity(uncompressed.len())); - u32::write_slice(&mut result, &[0; 5])?; // we come back to these later after we know more about the compressed data - - let table_start = result.position(); - pack_encoding_table( - &frequencies, - min_code_index, - max_code_index, - &mut result, - )?; - - let data_start = result.position(); - let bit_count = encode_with_frequencies( - &frequencies, - uncompressed, - max_code_index, - &mut result - )?; - - // write meta data after this - result.set_position(0); - let table_length = data_start - table_start; - - u32::try_from(min_code_index)?.write(&mut result)?; - u32::try_from(max_code_index)?.write(&mut result)?; - u32::try_from(table_length)?.write(&mut result)?; - u32::try_from(bit_count)?.write(&mut result)?; - 0_u32.write(&mut result)?; - - Ok(result.into_inner()) -} - - -const ENCODE_BITS: u64 = 16; // literal (value) bit length -const DECODE_BITS: u64 = 14; // decoding bit size (>= 8) - -const ENCODING_TABLE_SIZE: usize = ((1 << ENCODE_BITS) + 1) as usize; -const DECODING_TABLE_SIZE: usize = (1 << DECODE_BITS) as usize; -const DECODE_MASK: u64 = DECODING_TABLE_SIZE as u64 - 1; - -const SHORT_ZEROCODE_RUN: u64 = 59; -const LONG_ZEROCODE_RUN: u64 = 63; -const SHORTEST_LONG_RUN: u64 = 2 + LONG_ZEROCODE_RUN - SHORT_ZEROCODE_RUN; -const LONGEST_LONG_RUN: u64 = 255 + SHORTEST_LONG_RUN; - - -#[derive(Clone, Debug, Eq, PartialEq)] -enum Code { - Empty, - Short(ShortCode), - Long(SmallVec<[u32; 2]>), // often 2, sometimes 4, rarely 8 -} - -#[derive(Clone, Debug, Eq, PartialEq)] -struct ShortCode { - value: u32, - len: u8, -} - -impl ShortCode { - #[inline] fn len(&self) -> u64 { u64::from(self.len) } -} - -/// Decode (uncompress) n bits based on encoding & decoding tables: -fn decode_with_tables( - encoding_table: &[u64], - decoding_table: &[Code], - mut input: &[u8], - input_bit_count: i32, - run_length_code: u32, - expected_output_size: usize, -) -> Result> -{ - let mut output = Vec::with_capacity(expected_output_size); - let mut code_bits = 0_u64; - let mut code_bit_count = 0_u64; - - while input.len() > 0 { - read_byte(&mut code_bits, &mut code_bit_count, &mut input)?; - - // Access decoding table - while code_bit_count >= DECODE_BITS { - let code_index = (code_bits >> (code_bit_count - DECODE_BITS)) & DECODE_MASK; - let code = &decoding_table[u64_to_usize(code_index)]; - - // Get short code - if let Code::Short(code) = code { - code_bit_count -= code.len(); - - read_code_into_vec( - code.value, - run_length_code, - &mut code_bits, - &mut code_bit_count, - &mut input, - &mut output, - expected_output_size, - )?; - } - else if let Code::Long(ref long_codes) = code { - debug_assert_ne!(long_codes.len(), 0); - - let long_code = long_codes.iter() - .filter_map(|&long_code|{ - let encoded_long_code = encoding_table[u32_to_usize(long_code)]; - let length = length(encoded_long_code); - - while code_bit_count < length && input.len() > 0 { - let err = read_byte(&mut code_bits, &mut code_bit_count, &mut input); - if let Err(err) = err { return Some(Err(err)); } - } - - if code_bit_count >= length { - let required_code = (code_bits >> (code_bit_count - length)) & ((1 << length) - 1); - - if self::code(encoded_long_code) == required_code { - code_bit_count -= length; - return Some(Ok(long_code)); - } - } - - None - - }) - .next() - .ok_or(Error::invalid(INVALID_CODE))?; - - read_code_into_vec( - long_code?, - run_length_code, - &mut code_bits, - &mut code_bit_count, - &mut input, - &mut output, - expected_output_size, - )?; - } - else { - return Err(Error::invalid(INVALID_CODE)); - } - } - } - - let count = u64::try_from((8 - input_bit_count) & 7)?; - code_bits >>= count; - code_bit_count -= count; - - while code_bit_count > 0 { - let index = (code_bits << (DECODE_BITS - code_bit_count)) & DECODE_MASK; - let code = &decoding_table[u64_to_usize(index)]; - - if let Code::Short(short_code) = code { - if short_code.len() > code_bit_count { return Err(Error::invalid("code")) }; // FIXME why does this happen?? - code_bit_count -= short_code.len(); // FIXME may throw "attempted to subtract with overflow" - - read_code_into_vec( - short_code.value, - run_length_code, - &mut code_bits, - &mut code_bit_count, - &mut input, - &mut output, - expected_output_size, - )?; - } - else { - return Err(Error::invalid(INVALID_CODE)); - } - } - - if output.len() != expected_output_size { - return Err(Error::invalid(NOT_ENOUGH_DATA)); - } - - Ok(output) -} - -/// Build a decoding hash table based on the encoding table code: -/// - short codes (<= HUF_DECBITS) are resolved with a single table access; -/// - long code entry allocations are not optimized, because long codes are -/// unfrequent; -/// - decoding tables are used by hufDecode(); -fn build_decoding_table( - encoding_table: &[u64], - min_code_index: usize, - max_code_index: usize, -) -> Result> -{ - let mut decoding_table = vec![Code::Empty; DECODING_TABLE_SIZE]; // not an array because of code not being copy - - for (code_index, &encoded_code) in encoding_table[..= max_code_index].iter().enumerate().skip(min_code_index) { - let code_index = u32::try_from(code_index).unwrap(); - - let code = code(encoded_code); - let length = length(encoded_code); - - if code >> length != 0 { - return Err(Error::invalid(INVALID_TABLE_ENTRY)); - } - - if length > DECODE_BITS { - let long_code = &mut decoding_table[u64_to_usize(code >> (length - DECODE_BITS))]; - - match long_code { - Code::Empty => *long_code = Code::Long(smallvec![code_index]), - Code::Long(lits) => lits.push(code_index), - _ => { return Err(Error::invalid(INVALID_TABLE_ENTRY)); } - } - } - else if length != 0 { - let default_value = Code::Short(ShortCode { - value: code_index, - len: length as u8, - }); - - let start_index = u64_to_usize(code << (DECODE_BITS - length)); - let count = u64_to_usize(1 << (DECODE_BITS - length)); - - for value in &mut decoding_table[start_index .. start_index + count] { - *value = default_value.clone(); - } - } - } - - Ok(decoding_table) -} - -/// Run-length-decompresses all zero runs from the packed table to the encoding table -fn read_encoding_table( - packed: &mut impl Read, - min_code_index: usize, - max_code_index: usize, -) -> Result> -{ - let mut code_bits = 0_u64; - let mut code_bit_count = 0_u64; - - // TODO push() into encoding table instead of index stuff? - let mut encoding_table = vec![0_u64; ENCODING_TABLE_SIZE]; - let mut code_index = min_code_index; - while code_index <= max_code_index { - let code_len = read_bits(6, &mut code_bits, &mut code_bit_count, packed)?; - encoding_table[code_index] = code_len; - - if code_len == LONG_ZEROCODE_RUN { - let zerun_bits = read_bits(8, &mut code_bits, &mut code_bit_count, packed)?; - let zerun = usize::try_from(zerun_bits + SHORTEST_LONG_RUN).unwrap(); - - if code_index + zerun > max_code_index + 1 { - return Err(Error::invalid(TABLE_TOO_LONG)); - } - - for value in &mut encoding_table[code_index..code_index + zerun] { - *value = 0; - } - - code_index += zerun; - } - else if code_len >= SHORT_ZEROCODE_RUN { - let duplication_count = usize::try_from(code_len - SHORT_ZEROCODE_RUN + 2).unwrap(); - if code_index + duplication_count > max_code_index + 1 { - return Err(Error::invalid(TABLE_TOO_LONG)); - } - - for value in &mut encoding_table[code_index .. code_index + duplication_count] { - *value = 0; - } - - code_index += duplication_count; - } - else { - code_index += 1; - } - } - - build_canonical_table(&mut encoding_table); - Ok(encoding_table) -} - -// TODO Use BitStreamReader for all the bit reads?! -#[inline] -fn read_bits( - count: u64, - code_bits: &mut u64, - code_bit_count: &mut u64, - input: &mut impl Read, -) -> Result -{ - while *code_bit_count < count { - read_byte(code_bits, code_bit_count, input)?; - } - - *code_bit_count -= count; - Ok((*code_bits >> *code_bit_count) & ((1 << count) - 1)) -} - -#[inline] -fn read_byte(code_bits: &mut u64, bit_count: &mut u64, input: &mut impl Read) -> UnitResult { - *code_bits = (*code_bits << 8) | u8::read(input)? as u64; - *bit_count += 8; - Ok(()) -} - -#[inline] -fn read_code_into_vec( - code: u32, - run_length_code: u32, - code_bits: &mut u64, - code_bit_count: &mut u64, - read: &mut impl Read, - out: &mut Vec, - max_len: usize, -) -> UnitResult -{ - if code == run_length_code { // code may be too large for u16 - if *code_bit_count < 8 { - read_byte(code_bits, code_bit_count, read)?; - } - - *code_bit_count -= 8; - - let code_repetitions = usize::from((*code_bits >> *code_bit_count) as u8); - - if out.len() + code_repetitions > max_len { - return Err(Error::invalid(TOO_MUCH_DATA)); - } - else if out.is_empty() { - return Err(Error::invalid(NOT_ENOUGH_DATA)); - } - - let repeated_code = *out.last().unwrap(); - out.extend(std::iter::repeat(repeated_code).take(code_repetitions)); - } - else if out.len() < max_len { // implies that code is not larger than u16??? - out.push(u16::try_from(code)?); - } - else { - return Err(Error::invalid(TOO_MUCH_DATA)); - } - - Ok(()) -} - -fn count_frequencies(data: &[u16]) -> Vec { - let mut frequencies = vec![0_u64; ENCODING_TABLE_SIZE]; - - for value in data { - frequencies[*value as usize] += 1; - } - - frequencies -} - -fn write_bits( - count: u64, - bits: u64, - code_bits: &mut u64, - code_bit_count: &mut u64, - mut out: impl Write, -) -> UnitResult -{ - *code_bits = (*code_bits << count) | bits; - *code_bit_count += count; - - while *code_bit_count >= 8 { - *code_bit_count -= 8; - out.write(&[ - (*code_bits >> *code_bit_count) as u8 // TODO make sure never or always wraps? - ])?; - } - - Ok(()) -} - -fn write_code(scode: u64, code_bits: &mut u64, code_bit_count: &mut u64, mut out: impl Write) -> UnitResult { - write_bits(length(scode), code(scode), code_bits, code_bit_count, &mut out) -} - -#[inline(always)] -fn send_code( - scode: u64, - run_count: u64, - run_code: u64, - code_bits: &mut u64, - code_bit_count: &mut u64, - mut out: impl Write, -) -> UnitResult -{ - // Output a run of runCount instances of the symbol sCount. - // Output the symbols explicitly, or if that is shorter, output - // the sCode symbol once followed by a runCode symbol and runCount - // expressed as an 8-bit number. - if length(scode) + length(run_code) + 8 < length(scode) * run_count { - write_code(scode, code_bits, code_bit_count, &mut out)?; - write_code(run_code, code_bits, code_bit_count, &mut out)?; - write_bits(8, run_count, code_bits, code_bit_count, &mut out)?; - } - else { - for _ in 0 ..= run_count { - write_code(scode, code_bits, code_bit_count, &mut out)?; - } - } - - Ok(()) -} - -fn encode_with_frequencies( - frequencies: &[u64], - uncompressed: &[u16], - run_length_code: usize, - mut out: &mut Cursor>, -) -> Result -{ - let mut code_bits = 0; - let mut code_bit_count = 0; - - let mut run_start_value = uncompressed[0]; - let mut run_length = 0; - - let start_position = out.position(); - - // Loop on input values - for ¤t_value in &uncompressed[1..] { - // Count same values or send code - if run_start_value == current_value && run_length < 255 { - run_length += 1; - } - else { - send_code( - frequencies[run_start_value as usize], - run_length, - frequencies[run_length_code], - &mut code_bits, - &mut code_bit_count, - &mut out, - )?; - - run_length = 0; - } - - run_start_value = current_value; - } - - // Send remaining code - send_code( - frequencies[run_start_value as usize], - run_length, - frequencies[run_length_code], - &mut code_bits, - &mut code_bit_count, - &mut out, - )?; - - let data_length = out.position() - start_position; // we shouldn't count the last byte write - - if code_bit_count != 0 { - out.write(&[ - (code_bits << (8 - code_bit_count) & 0xff) as u8 - ])?; - } - - Ok(data_length * 8 + code_bit_count) -} - -/// -/// Pack an encoding table: -/// - only code lengths, not actual codes, are stored -/// - runs of zeroes are compressed as follows: -/// -/// unpacked packed -/// -------------------------------- -/// 1 zero 0 (6 bits) -/// 2 zeroes 59 -/// 3 zeroes 60 -/// 4 zeroes 61 -/// 5 zeroes 62 -/// n zeroes (6 or more) 63 n-6 (6 + 8 bits) -/// -fn pack_encoding_table( - frequencies: &[u64], - min_index: usize, - max_index: usize, - mut out: &mut Cursor>, -) -> UnitResult -{ - let mut code_bits = 0_u64; - let mut code_bit_count = 0_u64; - - let mut frequency_index = min_index; - while frequency_index <= max_index { // TODO slice iteration? - let code_length = length(frequencies[frequency_index]); - - if code_length == 0 { - let mut zero_run = 1; - - while frequency_index < max_index && zero_run < LONGEST_LONG_RUN { - if length(frequencies[frequency_index + 1]) > 0 { - break; - } - - frequency_index += 1; - zero_run += 1; - } - - if zero_run >= 2 { - if zero_run >= SHORTEST_LONG_RUN { - write_bits(6, LONG_ZEROCODE_RUN, &mut code_bits, &mut code_bit_count, &mut out)?; - write_bits(8, zero_run - SHORTEST_LONG_RUN, &mut code_bits, &mut code_bit_count, &mut out)?; - } - else { - write_bits(6, SHORT_ZEROCODE_RUN + zero_run - 2, &mut code_bits, &mut code_bit_count, &mut out)?; - } - - frequency_index += 1; // we must increment or else this may go very wrong - continue; - } - } - - write_bits(6, code_length, &mut code_bits, &mut code_bit_count, &mut out)?; - frequency_index += 1; - } - - if code_bit_count > 0 { - out.write(&[ - (code_bits << (8 - code_bit_count)) as u8 - ])?; - } - - Ok(()) -} - -/// Build a "canonical" Huffman code table: -/// - for each (uncompressed) symbol, code contains the length -/// of the corresponding code (in the compressed data) -/// - canonical codes are computed and stored in code -/// - the rules for constructing canonical codes are as follows: -/// * shorter codes (if filled with zeroes to the right) -/// have a numerically higher value than longer codes -/// * for codes with the same length, numerical values -/// increase with numerical symbol values -/// - because the canonical code table can be constructed from -/// symbol lengths alone, the code table can be transmitted -/// without sending the actual code values -/// - see http://www.compressconsult.com/huffman/ -fn build_canonical_table(code_table: &mut [u64]) { - debug_assert_eq!(code_table.len(), ENCODING_TABLE_SIZE); - - let mut count_per_code = [0_u64; 59]; - - for &code in code_table.iter() { - count_per_code[u64_to_usize(code)] += 1; - } - - // For each i from 58 through 1, compute the - // numerically lowest code with length i, and - // store that code in n[i]. - { - let mut code = 0_u64; // TODO use foldr? - for count in &mut count_per_code.iter_mut().rev() { - let next_code = (code + *count) >> 1; - *count = code; - code = next_code; - } - } - - // code[i] contains the length, l, of the - // code for symbol i. Assign the next available - // code of length l to the symbol and store both - // l and the code in code[i]. // TODO iter + filter ? - for symbol_length in code_table.iter_mut() { - let current_length = *symbol_length; - let code_index = u64_to_usize(current_length); - if current_length > 0 { - *symbol_length = current_length | (count_per_code[code_index] << 6); - count_per_code[code_index] += 1; - } - } -} - - -/// Compute Huffman codes (based on frq input) and store them in frq: -/// - code structure is : [63:lsb - 6:msb] | [5-0: bit length]; -/// - max code length is 58 bits; -/// - codes outside the range [im-iM] have a null length (unused values); -/// - original frequencies are destroyed; -/// - encoding tables are used by hufEncode() and hufBuildDecTable(); -/// -/// NB: The following code "(*a == *b) && (a > b))" was added to ensure -/// elements in the heap with the same value are sorted by index. -/// This is to ensure, the STL make_heap()/pop_heap()/push_heap() methods -/// produced a resultant sorted heap that is identical across OSes. -fn build_encoding_table( - frequencies: &mut [u64], // input frequencies, output encoding table -) -> (usize, usize) // return frequency max min range -{ - debug_assert_eq!(frequencies.len(), ENCODING_TABLE_SIZE); - - /// Frequency with position, used for MinHeap. - #[derive(Eq, PartialEq, Copy, Clone)] - struct HeapFrequency { - position: usize, - frequency: u64, - } - - impl Ord for HeapFrequency { - fn cmp(&self, other: &Self) -> Ordering { - other.frequency.cmp(&self.frequency) - .then_with(|| other.position.cmp(&self.position)) - } - } - - impl PartialOrd for HeapFrequency { - fn partial_cmp(&self, other: &Self) -> Option { Some(self.cmp(other)) } - } - - // This function assumes that when it is called, array frq - // indicates the frequency of all possible symbols in the data - // that are to be Huffman-encoded. (frq[i] contains the number - // of occurrences of symbol i in the data.) - // - // The loop below does three things: - // - // 1) Finds the minimum and maximum indices that point - // to non-zero entries in frq: - // - // frq[im] != 0, and frq[i] == 0 for all i < im - // frq[iM] != 0, and frq[i] == 0 for all i > iM - // - // 2) Fills array fHeap with pointers to all non-zero - // entries in frq. - // - // 3) Initializes array hlink such that hlink[i] == i - // for all array entries. - - // We need to use vec here or we overflow the stack. - let mut links = vec![0_usize; ENCODING_TABLE_SIZE]; - let mut frequency_heap = vec![0_usize; ENCODING_TABLE_SIZE]; - - // This is a good solution since we don't have usize::MAX items (no panics or UB), - // and since this is short-circuit, it stops at the first in order non zero element. - let min_frequency_index = frequencies.iter().position(|f| *f != 0).unwrap_or(0); - - let mut max_frequency_index = 0; - let mut frequency_count = 0; - - // assert bounds check to optimize away bounds check in loops - assert!(links.len() >= ENCODING_TABLE_SIZE); - assert!(frequencies.len() >= ENCODING_TABLE_SIZE); - - for index in min_frequency_index..ENCODING_TABLE_SIZE { - links[index] = index; // TODO for x in links.iter().enumerate() - - if frequencies[index] != 0 { - frequency_heap[frequency_count] = index; - max_frequency_index = index; - frequency_count += 1; - } - } - - - // Add a pseudo-symbol, with a frequency count of 1, to frq; - // adjust the fHeap and hlink array accordingly. Function - // hufEncode() uses the pseudo-symbol for run-length encoding. - - max_frequency_index += 1; - frequencies[max_frequency_index] = 1; - frequency_heap[frequency_count] = max_frequency_index; - frequency_count += 1; - - // Build an array, scode, such that scode[i] contains the number - // of bits assigned to symbol i. Conceptually this is done by - // constructing a tree whose leaves are the symbols with non-zero - // frequency: - // - // Make a heap that contains all symbols with a non-zero frequency, - // with the least frequent symbol on top. - // - // Repeat until only one symbol is left on the heap: - // - // Take the two least frequent symbols off the top of the heap. - // Create a new node that has first two nodes as children, and - // whose frequency is the sum of the frequencies of the first - // two nodes. Put the new node back into the heap. - // - // The last node left on the heap is the root of the tree. For each - // leaf node, the distance between the root and the leaf is the length - // of the code for the corresponding symbol. - // - // The loop below doesn't actually build the tree; instead we compute - // the distances of the leaves from the root on the fly. When a new - // node is added to the heap, then that node's descendants are linked - // into a single linear list that starts at the new node, and the code - // lengths of the descendants (that is, their distance from the root - // of the tree) are incremented by one. - let mut heap = BinaryHeap::with_capacity(frequency_count); - for index in frequency_heap.drain(..frequency_count) { - heap.push(HeapFrequency { position: index, frequency: frequencies[index] }); - } - - let mut s_code = vec![0_u64; ENCODING_TABLE_SIZE]; - - while frequency_count > 1 { - // Find the indices, mm and m, of the two smallest non-zero frq - // values in fHeap, add the smallest frq to the second-smallest - // frq, and remove the smallest frq value from fHeap. - let (high_position, low_position) = { - let smallest_frequency = heap.pop().expect("heap empty bug"); - frequency_count -= 1; - - let mut second_smallest_frequency = heap.peek_mut().expect("heap empty bug"); - second_smallest_frequency.frequency += smallest_frequency.frequency; - - (second_smallest_frequency.position, smallest_frequency.position) - }; - - // The entries in scode are linked into lists with the - // entries in hlink serving as "next" pointers and with - // the end of a list marked by hlink[j] == j. - // - // Traverse the lists that start at scode[m] and scode[mm]. - // For each element visited, increment the length of the - // corresponding code by one bit. (If we visit scode[j] - // during the traversal, then the code for symbol j becomes - // one bit longer.) - // - // Merge the lists that start at scode[m] and scode[mm] - // into a single list that starts at scode[m]. - - // Add a bit to all codes in the first list. - let mut index = high_position; // TODO fold() - loop { - s_code[index] += 1; - debug_assert!(s_code[index] <= 58); - - // merge the two lists - if links[index] == index { - links[index] = low_position; - break; - } - - index = links[index]; - } - - // Add a bit to all codes in the second list - let mut index = low_position; // TODO fold() - loop { - s_code[index] += 1; - debug_assert!(s_code[index] <= 58); - - if links[index] == index { - break; - } - - index = links[index]; - } - } - - // Build a canonical Huffman code table, replacing the code - // lengths in scode with (code, code length) pairs. Copy the - // code table from scode into frq. - build_canonical_table(&mut s_code); - frequencies.copy_from_slice(&s_code); - - (min_frequency_index, max_frequency_index) -} - - -#[inline] fn length(code: u64) -> u64 { code & 63 } -#[inline] fn code(code: u64) -> u64 { code >> 6 } - -const INVALID_BIT_COUNT: &'static str = "invalid number of bits"; -const INVALID_TABLE_ENTRY: &'static str = "invalid code table entry"; -const NOT_ENOUGH_DATA: &'static str = "decoded data are shorter than expected"; -const INVALID_TABLE_SIZE: &'static str = "unexpected end of code table data"; -const TABLE_TOO_LONG: &'static str = "code table is longer than expected"; -const INVALID_CODE: &'static str = "invalid code"; -const TOO_MUCH_DATA: &'static str = "decoded data are longer than expected"; - - -#[cfg(test)] -mod test { - use super::*; - use rand::{Rng, SeedableRng}; - - const UNCOMPRESSED_ARRAY: [u16; 100] = [ - 3852, 2432, 33635, 49381, 10100, 15095, 62693, 63738, 62359, 5013, 7715, 59875, 28182, - 34449, 19983, 20399, 63407, 29486, 4877, 26738, 44815, 14042, 46091, 48228, 25682, 35412, - 7582, 65069, 6632, 54124, 13798, 27503, 52154, 61961, 30474, 46880, 39097, 15754, 52897, - 42371, 54053, 14178, 48276, 34591, 42602, 32126, 42062, 31474, 16274, 55991, 2882, 17039, - 56389, 20835, 57057, 54081, 3414, 33957, 52584, 10222, 25139, 40002, 44980, 1602, 48021, - 19703, 6562, 61777, 41582, 201, 31253, 51790, 15888, 40921, 3627, 12184, 16036, 26349, - 3159, 29002, 14535, 50632, 18118, 33583, 18878, 59470, 32835, 9347, 16991, 21303, 26263, - 8312, 14017, 41777, 43240, 3500, 60250, 52437, 45715, 61520, - ]; - - const UNCOMPRESSED_ARRAY_SPECIAL: [u16; 100] = [ - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28182, - 0, 65534, 0, 65534, 0, 65534, 0, 65534, 0, 0, 0, 0, 0, - 0, 0, 0, 54124, 13798, 27503, 52154, 61961, 30474, 46880, 39097, 15754, 52897, - 42371, 54053, 14178, 48276, 34591, 42602, 32126, 42062, 31474, 16274, 55991, 2882, 17039, - 56389, 20835, 57057, 54081, 3414, 33957, 52584, 10222, 25139, 40002, 44980, 1602, 48021, - 19703, 6562, 61777, 41582, 201, 31253, 51790, 15888, 40921, 3627, 12184, 16036, 26349, - 3159, 29002, 14535, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, - 65534, 65534, 65534, 65534, 65534, 65534, 65534, 65534, 65534, - ]; - - const COMPRESSED_ARRAY: [u8; 703] = [ - 0xc9, 0x0, 0x0, 0x0, 0x2e, 0xfe, 0x0, 0x0, 0x56, 0x2, 0x0, 0x0, 0xa2, 0x2, 0x0, 0x0, 0x0, - 0x0, 0x0, 0x0, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xd6, 0x47, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x28, 0x1f, 0xff, 0xff, 0xed, 0x87, 0xff, 0xff, 0xf0, - 0x91, 0xff, 0xf8, 0x1f, 0xf4, 0xf1, 0xff, 0x78, 0x1f, 0xfd, 0xa1, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xfa, 0xc7, 0xfe, 0x4, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xed, 0x1f, 0xf3, 0xf1, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xe8, 0x7, 0xfd, 0xf8, - 0x7f, 0xff, 0xff, 0xff, 0xfd, 0x10, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x51, 0xff, - 0xff, 0xff, 0xff, 0xfe, 0x1, 0xff, 0x73, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe, 0x0, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xfc, 0xa4, 0x7f, 0xf5, 0x7, 0xfc, 0x48, 0x7f, 0xe0, 0x47, 0xff, 0xff, - 0xf5, 0x91, 0xff, 0xff, 0xff, 0xff, 0xf1, 0xf1, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x21, 0xff, - 0x7f, 0x1f, 0xf8, 0xd1, 0xff, 0xe7, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xbc, 0x1f, 0xf2, 0x91, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1c, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xe7, - 0x1f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfc, 0x8c, 0x7f, 0xff, 0xff, 0xc, 0x1f, 0xff, 0xff, - 0xe5, 0x7, 0xff, 0xff, 0xfa, 0x81, 0xff, 0xff, 0xff, 0x20, 0x7f, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe, 0xbc, 0x7f, 0xff, 0xff, 0xff, 0xfc, 0x38, 0x7f, 0xff, - 0xff, 0xff, 0xfc, 0xd0, 0x7f, 0xd3, 0xc7, 0xff, 0xff, 0xf7, 0x91, 0xff, 0xff, 0xff, 0xff, - 0xfe, 0xc1, 0xff, 0xff, 0xff, 0xff, 0xf9, 0x61, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc7, - 0x87, 0xff, 0xff, 0xfd, 0x81, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xf1, 0x87, 0xff, 0xff, - 0xff, 0xff, 0xfe, 0x87, 0xff, 0x58, 0x7f, 0xff, 0xff, 0xff, 0xfd, 0xec, 0x7f, 0xff, 0xff, - 0xff, 0xfe, 0xd0, 0x7f, 0xff, 0xff, 0xff, 0xff, 0x6c, 0x7f, 0xcb, 0x47, 0xff, 0xff, 0xf3, - 0x61, 0xff, 0xff, 0xff, 0x80, 0x7f, 0xe1, 0xc7, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x1f, - 0x1f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x18, 0x1f, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xfd, 0xcc, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xf8, 0x11, 0xff, 0xff, - 0xff, 0xff, 0xf8, 0x41, 0xff, 0xbc, 0x1f, 0xff, 0xff, 0xc4, 0x47, 0xff, 0xff, 0xf2, 0x91, - 0xff, 0xe0, 0x1f, 0xff, 0xff, 0xff, 0xff, 0x6d, 0x1f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0xff, 0x2, 0x1f, 0xf9, 0xe1, 0xff, 0xff, 0xff, 0xff, 0xfc, 0xe1, - 0xff, 0xff, 0xfd, 0xb0, 0x7f, 0xff, 0xff, 0xff, 0xff, 0xff, 0xe1, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0x5a, 0x1f, 0xfc, 0x81, 0xbf, 0x29, 0x1b, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xf3, 0x61, 0xbf, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xc8, 0x1b, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xf6, 0xb1, 0xbf, 0xff, 0xfd, 0x80, 0x6f, 0xff, - 0xff, 0xf, 0x1b, 0xf8, 0xc1, 0xbf, 0xff, 0xfc, 0xb4, 0x6f, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xda, 0x46, 0xfc, 0x54, 0x6f, 0xc9, 0x6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x21, 0x1b, 0xff, 0xff, 0xe0, 0x86, 0xff, 0xff, - 0xff, 0xff, 0xe2, 0xc6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, - 0xff, 0xff, 0xff, 0xff, 0xff, 0xf3, 0x91, 0xbf, 0xff, 0xfe, 0x24, 0x6f, 0xff, 0xff, 0x6b, - 0x1b, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfd, 0xb1, 0xbf, 0xfa, 0x1b, 0xfb, 0x11, - 0xbf, 0xff, 0xfe, 0x8, 0x6f, 0xff, 0xff, 0x42, 0x1b, 0xff, 0xff, 0xff, 0xff, 0xb9, 0x1b, - 0xff, 0xff, 0xcf, 0xc6, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xf1, 0x31, - 0x86, 0x10, 0x9, 0xb4, 0xe4, 0x4c, 0xf7, 0xef, 0x42, 0x87, 0x6a, 0xb5, 0xc2, 0x34, 0x9e, - 0x2f, 0x12, 0xae, 0x21, 0x68, 0xf2, 0xa8, 0x74, 0x37, 0xe1, 0x98, 0x14, 0x59, 0x57, 0x2c, - 0x24, 0x3b, 0x35, 0x6c, 0x1b, 0x8b, 0xcc, 0xe6, 0x13, 0x38, 0xc, 0x8e, 0xe2, 0xc, 0xfe, - 0x49, 0x73, 0xbc, 0x2b, 0x7b, 0x9, 0x27, 0x79, 0x14, 0xc, 0x94, 0x42, 0xf8, 0x7c, 0x1, - 0x8d, 0x26, 0xde, 0x87, 0x26, 0x71, 0x50, 0x45, 0xc6, 0x28, 0x40, 0xd5, 0xe, 0x8d, 0x8, - 0x1e, 0x4c, 0xa4, 0x79, 0x57, 0xf0, 0xc3, 0x6d, 0x5c, 0x6d, 0xc0, - ]; - - fn fill(rng: &mut impl Rng, size: usize) -> Vec { - if rng.gen_bool(0.2) { - let value = if rng.gen_bool(0.5) { 0 } else { u16::MAX }; - return vec![ value; size ]; - } - - let mut data = vec![0_u16; size]; - - data.iter_mut().for_each(|v| { - *v = rng.gen_range(0_u16 .. u16::MAX); - }); - - data - } - - /// Test using both input and output from a custom ILM OpenEXR test. - #[test] - fn compression_comparation() { - let raw = compress(&UNCOMPRESSED_ARRAY).unwrap(); - assert_eq!(raw, COMPRESSED_ARRAY.to_vec()); - } - - #[test] - fn round_trip() { - let mut random = rand::rngs::StdRng::from_seed(SEED); - let raw = fill(&mut random, u16::MAX as usize); - - let compressed = compress(&raw).unwrap(); - let uncompressed = decompress(&compressed, raw.len()).unwrap(); - - assert_eq!(uncompressed, raw); - } - - #[test] - fn repetitions_special() { - let raw = UNCOMPRESSED_ARRAY_SPECIAL; - - let compressed = compress(&raw).unwrap(); - let uncompressed = decompress(&compressed, raw.len()).unwrap(); - - assert_eq!(uncompressed, raw.to_vec()); - } - - #[test] - fn round_trip100() { - let mut random = rand::rngs::StdRng::from_seed(SEED); - - for size_multiplier in 1..10 { - let raw = fill(&mut random, size_multiplier * 50_000); - - let compressed = compress(&raw).unwrap(); - let uncompressed = decompress(&compressed, raw.len()).unwrap(); - - assert_eq!(uncompressed, raw); - } - } - - #[test] - fn test_zeroes(){ - let uncompressed: &[u16] = &[ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ]; - - let compressed = compress(uncompressed).unwrap(); - let decompressed = decompress(&compressed, uncompressed.len()).unwrap(); - - assert_eq!(uncompressed, decompressed.as_slice()); - } - - const SEED: [u8; 32] = [ - 12,155,32,34,112,109,98,54, - 12,255,32,34,112,109,98,55, - 12,155,32,34,12,109,98,54, - 12,35,32,34,112,109,48,54, - ]; -} -- cgit v1.2.3