-use io::bitreader::BitReader;
+use std::collections::HashMap;
+use std::cmp::{max, min};
+use super::bitreader::BitReader;
#[derive(Debug)]
pub enum CodebookError {
InvalidCode,
}
+#[derive(Debug, Copy, Clone)]
+pub enum CodebookMode {
+ MSB,
+ LSB,
+}
+
type CodebookResult<T> = Result<T, CodebookError>;
pub struct FullCodebookDesc<S> {
fn read_cb(&mut self, cb: &Codebook<S>) -> CodebookResult<S>;
}
+const TABLE_FILL_VALUE: u32 = 0x7F;
+const MAX_LUT_BITS: u8 = 10;
+
+fn fill_lut_msb(table: &mut Vec<u32>, off: usize,
+ code: u32, bits: u8, lut_bits: u8, symidx: u32, esc: bool) {
+ if !esc {
+ let fill_len = lut_bits - bits;
+ let fill_size = 1 << fill_len;
+ let fill_code = code << (lut_bits - bits);
+ let lut_value = (symidx << 8) | (bits as u32);
+ for j in 0..fill_size {
+ let idx = (fill_code + j) as usize;
+ table[idx + off] = lut_value;
+ }
+ } else {
+ let idx = (code as usize) + off;
+ table[idx] = (symidx << 8) | 0x80 | (bits as u32);
+ }
+}
+
+fn fill_lut_lsb(table: &mut Vec<u32>, off: usize,
+ code: u32, bits: u8, lut_bits: u8, symidx: u32, esc: bool) {
+ if !esc {
+ let fill_len = lut_bits - bits;
+ let fill_size = 1 << fill_len;
+ let fill_code = code;
+ let step = lut_bits - fill_len;
+ for j in 0..fill_size {
+ let idx = (fill_code + (j << step)) as usize;
+ table[idx + off] = (symidx << 8) | (bits as u32);
+ }
+ } else {
+ let idx = (code as usize) + off;
+ table[idx] = (symidx << 8) | 0x80 | (bits as u32);
+ }
+}
+
+fn fill_lut(table: &mut Vec<u32>, mode: CodebookMode,
+ off: usize, code: u32, bits: u8, lut_bits: u8, symidx: u32, esc: bool) -> bool {
+ match mode {
+ CodebookMode::MSB => fill_lut_msb(table, off, code, bits, lut_bits, symidx, esc),
+ CodebookMode::LSB => fill_lut_lsb(table, off, code, bits, lut_bits, symidx, esc),
+ };
+ bits > lut_bits
+}
+
+fn resize_table(table: &mut Vec<u32>, bits: u8) -> CodebookResult<u32> {
+ let add_size = (1 << bits) as usize;
+ table.reserve(add_size);
+ let cur_off = table.len() as u32;
+ let new_size = table.len() + add_size;
+ if table.capacity() < new_size { return Err(CodebookError::MemoryError); }
+ table.resize(new_size, TABLE_FILL_VALUE);
+ Ok(cur_off)
+}
+
+
+fn extract_lut_part(code: u32, bits: u8, lut_bits: u8, mode: CodebookMode) -> u32 {
+ match mode {
+ CodebookMode::MSB => code >> (bits - lut_bits),
+ CodebookMode::LSB => code & ((1 << lut_bits) - 1),
+ }
+}
+
+fn extract_esc_part(code: u32, bits: u8, lut_bits: u8, mode: CodebookMode) -> u32 {
+ match mode {
+ CodebookMode::MSB => code & ((1 << (bits - lut_bits)) - 1),
+ CodebookMode::LSB => code >> lut_bits,
+ }
+}
+
+#[derive(Clone,Copy)]
+struct Code {
+ code: u32,
+ bits: u8,
+ idx: usize,
+}
+
+struct CodeBucket {
+ maxlen: u8,
+ offset: usize,
+ codes: Vec<Code>,
+}
+
+impl CodeBucket {
+ fn new() -> Self {
+ CodeBucket { maxlen: 0, offset: 0, codes: Vec::new() }
+ }
+ fn add_code(&mut self, c: Code) {
+ if c.bits > self.maxlen { self.maxlen = c.bits; }
+ self.codes.push(c);
+ }
+}
+
+type EscapeCodes = HashMap<u32, CodeBucket>;
+
+fn add_esc_code(cc: &mut EscapeCodes, key: u32, code: u32, bits: u8, idx: usize) {
+ if !cc.contains_key(&key) { cc.insert(key, CodeBucket::new()); }
+ let b = cc.get_mut(&key);
+ if let Some(bucket) = b {
+ bucket.add_code(Code {code: code, bits: bits, idx: idx });
+ } else { panic!("no bucket when expected!"); }
+}
+
+fn build_esc_lut(table: &mut Vec<u32>,
+ mode: CodebookMode,
+ bucket: &CodeBucket) -> CodebookResult<()> {
+ let mut escape_list: EscapeCodes = HashMap::new();
+ let maxlen = if bucket.maxlen > MAX_LUT_BITS { MAX_LUT_BITS } else { bucket.maxlen };
+
+ for code in &bucket.codes {
+ let bits = code.bits;
+ if code.bits <= MAX_LUT_BITS {
+ fill_lut(table, mode, bucket.offset, code.code, bits,
+ maxlen, code.idx as u32, false);
+ } else {
+ let ckey = extract_lut_part(code.code, bits, MAX_LUT_BITS, mode);
+ let cval = extract_esc_part(code.code, bits, MAX_LUT_BITS, mode);
+ add_esc_code(&mut escape_list, ckey, cval, bits - MAX_LUT_BITS, code.idx);
+ }
+ }
+
+ let cur_offset = bucket.offset;
+ for (ckey, sec_bucket) in &mut escape_list {
+ let key = *ckey as u32;
+ let maxlen = min(sec_bucket.maxlen, MAX_LUT_BITS);
+ let new_off = resize_table(table, maxlen)?;
+ fill_lut(table, mode, cur_offset, key, maxlen,
+ MAX_LUT_BITS, new_off, true);
+ sec_bucket.offset = new_off as usize;
+ }
+
+ for (_, sec_bucket) in &escape_list {
+ build_esc_lut(table, mode, sec_bucket)?;
+ }
+
+ Ok(())
+}
+
impl<S: Copy> Codebook<S> {
-//todo allow add escapes
- pub fn new(cb: &mut CodebookDescReader<S>) -> CodebookResult<Self> {
+
+ pub fn new(cb: &mut CodebookDescReader<S>, mode: CodebookMode) -> CodebookResult<Self> {
let mut maxbits = 0;
let mut nnz = 0;
+ let mut escape_list: EscapeCodes = HashMap::new();
+
+ let mut symidx: usize = 0;
for i in 0..cb.len() {
let bits = cb.bits(i);
- if bits > 0 { nnz = nnz + 1; }
- if bits > maxbits {
- maxbits = bits;
+ if bits > 0 {
+ nnz = nnz + 1;
+ if cb.code(i) >= (1 << bits) {
+ return Err(CodebookError::InvalidCodebook);
+ }
}
+ maxbits = max(bits, maxbits);
+ if bits > MAX_LUT_BITS {
+ let code = cb.code(i);
+ let ckey = extract_lut_part(code, bits, MAX_LUT_BITS, mode);
+ let cval = extract_esc_part(code, bits, MAX_LUT_BITS, mode);
+ add_esc_code(&mut escape_list, ckey, cval, bits - MAX_LUT_BITS, symidx);
+ }
+ if bits > 0 { symidx = symidx + 1; }
}
if maxbits == 0 { return Err(CodebookError::InvalidCodebook); }
- let mut table: Vec<u32> = Vec::new();
- let mut syms: Vec<S> = Vec::new();
+ if maxbits > MAX_LUT_BITS { maxbits = MAX_LUT_BITS; }
+
let tab_len = 1 << maxbits;
- table.reserve(tab_len);
+ let mut table: Vec<u32> = Vec::with_capacity(tab_len);
+ let mut syms: Vec<S> = Vec::with_capacity(nnz);
if table.capacity() < tab_len { return Err(CodebookError::MemoryError); }
- table.resize(tab_len, 0xFF);
- syms.reserve(nnz);
- if syms.capacity() < nnz { return Err(CodebookError::MemoryError); }
+ if syms.capacity() < nnz { return Err(CodebookError::MemoryError); }
+ table.resize(tab_len, TABLE_FILL_VALUE);
let mut symidx: u32 = 0;
for i in 0..cb.len() {
let bits = cb.bits(i);
+ let code = cb.code(i);
if bits == 0 { continue; }
- let code = cb.code(i) << (maxbits - bits);
- let fill_len = 1 << (maxbits - bits);
- for j in 0..fill_len {
- let idx = (code + j) as usize;
- table[idx] = (symidx << 8) | (bits as u32);
+ if bits <= MAX_LUT_BITS {
+ fill_lut(&mut table, mode, 0, code, bits, maxbits, symidx, false);
+ } else {
+ let ckey = extract_lut_part(code, bits, MAX_LUT_BITS, mode) as usize;
+ if table[ckey] == TABLE_FILL_VALUE {
+ let key = ckey as u32;
+ if let Some(bucket) = escape_list.get_mut(&key) {
+ let maxlen = min(bucket.maxlen, MAX_LUT_BITS);
+ let new_off = resize_table(&mut table, maxlen)?;
+ fill_lut(&mut table, mode, 0, key, maxlen, MAX_LUT_BITS, new_off, true);
+ bucket.offset = new_off as usize;
+ }
+ }
}
symidx = symidx + 1;
}
+ for (_, bucket) in &escape_list {
+ build_esc_lut(&mut table, mode, &bucket)?;
+ }
+
for i in 0..cb.len() {
if cb.bits(i) > 0 {
syms.push(cb.sym(i));
impl<'a, S: Copy> CodebookReader<S> for BitReader<'a> {
#[allow(unused_variables)]
fn read_cb(&mut self, cb: &Codebook<S>) -> CodebookResult<S> {
- let lut_idx = self.peek(cb.lut_bits) as usize;
- let bits = cb.table[lut_idx] & 0xFF;
- let idx = (cb.table[lut_idx] >> 8) as usize;
- if bits == 0xFF || (bits as isize) > self.left() {
- return Err(CodebookError::InvalidCode);
+ let mut esc = true;
+ let mut idx = 0;
+ let mut lut_bits = cb.lut_bits;
+ while esc {
+ let lut_idx = (self.peek(lut_bits) as usize) + (idx as usize);
+ if cb.table[lut_idx] == TABLE_FILL_VALUE { return Err(CodebookError::InvalidCode); }
+ let bits = cb.table[lut_idx] & 0x7F;
+ esc = (cb.table[lut_idx] & 0x80) != 0;
+ idx = (cb.table[lut_idx] >> 8) as usize;
+ if (bits as isize) > self.left() {
+ return Err(CodebookError::InvalidCode);
+ }
+ let skip_bits = if esc { lut_bits as u32 } else { bits };
+ if let Err(_) = self.skip(skip_bits as u32) {}
+ lut_bits = bits as u8;
}
- if let Err(_) = self.skip(bits) {}
- let sym = cb.syms[idx];
- return Ok(sym)
+ Ok(cb.syms[idx])
}
}
fn len(&mut self) -> usize { self.data.len() }
}
+pub struct TableCodebookDescReader<CodeType:'static, IndexType:'static> {
+ bits: &'static [u8],
+ codes: &'static [CodeType],
+ idx_map: fn(usize) -> IndexType,
+}
+
+impl<'a, CodeType, IndexType> TableCodebookDescReader<CodeType, IndexType> {
+ pub fn new(codes: &'static [CodeType], bits: &'static [u8], idx_map: fn(usize) -> IndexType) -> Self {
+ Self { bits, codes, idx_map }
+ }
+}
+impl<CodeType: Copy+Into<u32>, IndexType> CodebookDescReader<IndexType> for TableCodebookDescReader<CodeType, IndexType>
+{
+ fn bits(&mut self, idx: usize) -> u8 { self.bits[idx] }
+ fn code(&mut self, idx: usize) -> u32 { self.codes[idx].into() }
+ fn sym (&mut self, idx: usize) -> IndexType { (self.idx_map)(idx) }
+ fn len(&mut self) -> usize { self.bits.len() }
+}
+
#[cfg(test)]
mod test {
use super::*;
- use io::bitreader::*;
+ use crate::io::bitreader::*;
#[test]
fn test_cb() {
let buf = &BITS;
let mut br = BitReader::new(buf, buf.len(), BitReaderMode::BE);
let mut cfr = FullCodebookDescReader::new(cb_desc);
- let cb = Codebook::new(&mut cfr).unwrap();
+ let cb = Codebook::new(&mut cfr, CodebookMode::MSB).unwrap();
assert_eq!(br.read_cb(&cb).unwrap(), 16);
assert_eq!(br.read_cb(&cb).unwrap(), -3);
assert_eq!(br.read_cb(&cb).unwrap(), 42);
ShortCodebookDesc { code: 0, bits: 0 },
ShortCodebookDesc { code: 0b110, bits: 3 },
ShortCodebookDesc { code: 0, bits: 0 },
- ShortCodebookDesc { code: 0b1110, bits: 4 }
+ ShortCodebookDesc { code: 0b11100, bits: 5 },
+ ShortCodebookDesc { code: 0b11101, bits: 5 },
+ ShortCodebookDesc { code: 0b1111010, bits: 7 },
+ ShortCodebookDesc { code: 0b1111011, bits: 7 },
+ ShortCodebookDesc { code: 0b1111110, bits: 7 },
+ ShortCodebookDesc { code: 0b11111111, bits: 8 }
);
let mut br2 = BitReader::new(buf, buf.len(), BitReaderMode::BE);
let mut cfr = ShortCodebookDescReader::new(scb_desc);
- let cb = Codebook::new(&mut cfr).unwrap();
+ let cb = Codebook::new(&mut cfr, CodebookMode::MSB).unwrap();
assert_eq!(br2.read_cb(&cb).unwrap(), 0);
assert_eq!(br2.read_cb(&cb).unwrap(), 2);
assert_eq!(br2.read_cb(&cb).unwrap(), 5);
- assert_eq!(br2.read_cb(&cb).unwrap(), 7);
+ assert_eq!(br2.read_cb(&cb).unwrap(), 8);
+
+ assert_eq!(reverse_bits(0b0000_0101_1011_1011_1101_1111_0111_1111, 32),
+ 0b1111_1110_1111_1011_1101_1101_1010_0000);
+
+ const BITS_LE: [u8; 3] = [0b11101111, 0b01110010, 0b01];
+ let buf = &BITS_LE;
+ let scble_desc: Vec<ShortCodebookDesc> = vec!(
+ ShortCodebookDesc { code: 0b00, bits: 2 },
+ ShortCodebookDesc { code: 0, bits: 0 },
+ ShortCodebookDesc { code: 0b01, bits: 2 },
+ ShortCodebookDesc { code: 0, bits: 0 },
+ ShortCodebookDesc { code: 0, bits: 0 },
+ ShortCodebookDesc { code: 0b011, bits: 3 },
+ ShortCodebookDesc { code: 0, bits: 0 },
+ ShortCodebookDesc { code: 0b10111, bits: 5 },
+ ShortCodebookDesc { code: 0b00111, bits: 5 },
+ ShortCodebookDesc { code: 0b0101111, bits: 7 },
+ ShortCodebookDesc { code: 0b0111111, bits: 7 },
+ ShortCodebookDesc { code: 0b1011101111, bits: 10 }
+ );
+ let mut brl = BitReader::new(buf, buf.len(), BitReaderMode::LE);
+ let mut cfr = ShortCodebookDescReader::new(scble_desc);
+ let cb = Codebook::new(&mut cfr, CodebookMode::LSB).unwrap();
+ assert_eq!(brl.read_cb(&cb).unwrap(), 11);
+ assert_eq!(brl.read_cb(&cb).unwrap(), 0);
+ assert_eq!(brl.read_cb(&cb).unwrap(), 7);
+ assert_eq!(brl.read_cb(&cb).unwrap(), 0);
}
}
projects / nihav.git / blobdiff