copyparty/copyparty/stolen/qrcodegen.py
2024-10-03 23:14:06 +00:00

614 lines
23 KiB
Python

# coding: utf-8
# modified copy of Project Nayuki's qrcodegen (MIT-licensed);
# https://github.com/nayuki/QR-Code-generator/blob/daa3114/python/qrcodegen.py
# the original ^ is extremely well commented so refer to that for explanations
# hacks: binary-only, auto-ecc, render, py2-compat
from __future__ import print_function, unicode_literals
import collections
import itertools
if True: # pylint: disable=using-constant-test
from collections.abc import Sequence
from typing import Callable, List, Optional, Tuple, Union
try:
range = xrange
except:
pass
def num_char_count_bits(ver: int) -> int:
return 16 if (ver + 7) // 17 else 8
class Ecc(object):
ordinal: int
formatbits: int
def __init__(self, i: int, fb: int) -> None:
self.ordinal = i
self.formatbits = fb
LOW: "Ecc"
MEDIUM: "Ecc"
QUARTILE: "Ecc"
HIGH: "Ecc"
Ecc.LOW = Ecc(0, 1)
Ecc.MEDIUM = Ecc(1, 0)
Ecc.QUARTILE = Ecc(2, 3)
Ecc.HIGH = Ecc(3, 2)
class QrSegment(object):
@staticmethod
def make_seg(data: Union[bytes, Sequence[int]]) -> "QrSegment":
bb = _BitBuffer()
for b in data:
bb.append_bits(b, 8)
return QrSegment(len(data), bb)
numchars: int # num bytes, not the same as the data's bit length
bitdata: List[int] # The data bits of this segment
def __init__(self, numch: int, bitdata: Sequence[int]) -> None:
if numch < 0:
raise ValueError()
self.numchars = numch
self.bitdata = list(bitdata)
@staticmethod
def get_total_bits(segs: Sequence["QrSegment"], ver: int) -> Optional[int]:
result = 0
for seg in segs:
ccbits: int = num_char_count_bits(ver)
if seg.numchars >= (1 << ccbits):
return None # segment length doesn't fit the field's bit width
result += 4 + ccbits + len(seg.bitdata)
return result
class QrCode(object):
@staticmethod
def encode_binary(data: Union[bytes, Sequence[int]]) -> "QrCode":
return QrCode.encode_segments([QrSegment.make_seg(data)])
@staticmethod
def encode_segments(
segs: Sequence[QrSegment],
ecl: Ecc = Ecc.LOW,
minver: int = 2,
maxver: int = 40,
mask: int = -1,
) -> "QrCode":
for ver in range(minver, maxver + 1):
datacapacitybits: int = QrCode._get_num_data_codewords(ver, ecl) * 8
datausedbits: Optional[int] = QrSegment.get_total_bits(segs, ver)
if (datausedbits is not None) and (datausedbits <= datacapacitybits):
break
assert datausedbits
for newecl in (
Ecc.MEDIUM,
Ecc.QUARTILE,
Ecc.HIGH,
):
if datausedbits <= QrCode._get_num_data_codewords(ver, newecl) * 8:
ecl = newecl
# Concatenate all segments to create the data bit string
bb = _BitBuffer()
for seg in segs:
bb.append_bits(4, 4)
bb.append_bits(seg.numchars, num_char_count_bits(ver))
bb.extend(seg.bitdata)
assert len(bb) == datausedbits
# Add terminator and pad up to a byte if applicable
datacapacitybits = QrCode._get_num_data_codewords(ver, ecl) * 8
assert len(bb) <= datacapacitybits
bb.append_bits(0, min(4, datacapacitybits - len(bb)))
bb.append_bits(0, -len(bb) % 8)
assert len(bb) % 8 == 0
# Pad with alternating bytes until data capacity is reached
for padbyte in itertools.cycle((0xEC, 0x11)):
if len(bb) >= datacapacitybits:
break
bb.append_bits(padbyte, 8)
# Pack bits into bytes in big endian
datacodewords = bytearray([0] * (len(bb) // 8))
for (i, bit) in enumerate(bb):
datacodewords[i >> 3] |= bit << (7 - (i & 7))
return QrCode(ver, ecl, datacodewords, mask)
ver: int
size: int # w/h; 21..177 (ver * 4 + 17)
ecclvl: Ecc
mask: int # 0..7
modules: List[List[bool]]
unmaskable: List[List[bool]]
def __init__(
self,
ver: int,
ecclvl: Ecc,
datacodewords: Union[bytes, Sequence[int]],
msk: int,
) -> None:
self.ver = ver
self.size = ver * 4 + 17
self.ecclvl = ecclvl
self.modules = [[False] * self.size for _ in range(self.size)]
self.unmaskable = [[False] * self.size for _ in range(self.size)]
# Compute ECC, draw modules
self._draw_function_patterns()
allcodewords: bytes = self._add_ecc_and_interleave(bytearray(datacodewords))
self._draw_codewords(allcodewords)
if msk == -1: # automask
minpenalty: int = 1 << 32
for i in range(8):
self._apply_mask(i)
self._draw_format_bits(i)
penalty = self._get_penalty_score()
if penalty < minpenalty:
msk = i
minpenalty = penalty
self._apply_mask(i) # xor/undo
assert 0 <= msk <= 7
self.mask = msk
self._apply_mask(msk) # Apply the final choice of mask
self._draw_format_bits(msk) # Overwrite old format bits
def render(self, zoom=1, pad=4) -> str:
tab = self.modules
sz = self.size
if sz % 2 and zoom == 1:
tab.append([False] * sz)
tab = [[False] * sz] * pad + tab + [[False] * sz] * pad
tab = [[False] * pad + x + [False] * pad for x in tab]
rows: list[str] = []
if zoom == 1:
for y in range(0, len(tab), 2):
row = ""
for x in range(len(tab[y])):
v = 2 if tab[y][x] else 0
v += 1 if tab[y + 1][x] else 0
row += " ▄▀█"[v]
rows.append(row)
else:
for tr in tab:
row = ""
for zb in tr:
row += ""[int(zb)] * 2
rows.append(row)
return "\n".join(rows)
def _draw_function_patterns(self) -> None:
# Draw horizontal and vertical timing patterns
for i in range(self.size):
self._set_function_module(6, i, i % 2 == 0)
self._set_function_module(i, 6, i % 2 == 0)
# Draw 3 finder patterns (all corners except bottom right; overwrites some timing modules)
self._draw_finder_pattern(3, 3)
self._draw_finder_pattern(self.size - 4, 3)
self._draw_finder_pattern(3, self.size - 4)
# Draw numerous alignment patterns
alignpatpos: List[int] = self._get_alignment_pattern_positions()
numalign: int = len(alignpatpos)
skips: Sequence[Tuple[int, int]] = (
(0, 0),
(0, numalign - 1),
(numalign - 1, 0),
)
for i in range(numalign):
for j in range(numalign):
if (i, j) not in skips: # avoid finder corners
self._draw_alignment_pattern(alignpatpos[i], alignpatpos[j])
# draw config data with dummy mask value; ctor overwrites it
self._draw_format_bits(0)
self._draw_ver()
def _draw_format_bits(self, mask: int) -> None:
# Calculate error correction code and pack bits; ecclvl is uint2, mask is uint3
data: int = self.ecclvl.formatbits << 3 | mask
rem: int = data
for _ in range(10):
rem = (rem << 1) ^ ((rem >> 9) * 0x537)
bits: int = (data << 10 | rem) ^ 0x5412 # uint15
assert bits >> 15 == 0
# first copy
for i in range(0, 6):
self._set_function_module(8, i, _get_bit(bits, i))
self._set_function_module(8, 7, _get_bit(bits, 6))
self._set_function_module(8, 8, _get_bit(bits, 7))
self._set_function_module(7, 8, _get_bit(bits, 8))
for i in range(9, 15):
self._set_function_module(14 - i, 8, _get_bit(bits, i))
# second copy
for i in range(0, 8):
self._set_function_module(self.size - 1 - i, 8, _get_bit(bits, i))
for i in range(8, 15):
self._set_function_module(8, self.size - 15 + i, _get_bit(bits, i))
self._set_function_module(8, self.size - 8, True) # Always dark
def _draw_ver(self) -> None:
if self.ver < 7:
return
# Calculate error correction code and pack bits
rem: int = self.ver # ver is uint6, 7..40
for _ in range(12):
rem = (rem << 1) ^ ((rem >> 11) * 0x1F25)
bits: int = self.ver << 12 | rem # uint18
assert bits >> 18 == 0
# Draw two copies
for i in range(18):
bit: bool = _get_bit(bits, i)
a: int = self.size - 11 + i % 3
b: int = i // 3
self._set_function_module(a, b, bit)
self._set_function_module(b, a, bit)
def _draw_finder_pattern(self, x: int, y: int) -> None:
for dy in range(-4, 5):
for dx in range(-4, 5):
xx, yy = x + dx, y + dy
if (0 <= xx < self.size) and (0 <= yy < self.size):
# Chebyshev/infinity norm
self._set_function_module(
xx, yy, max(abs(dx), abs(dy)) not in (2, 4)
)
def _draw_alignment_pattern(self, x: int, y: int) -> None:
for dy in range(-2, 3):
for dx in range(-2, 3):
self._set_function_module(x + dx, y + dy, max(abs(dx), abs(dy)) != 1)
def _set_function_module(self, x: int, y: int, isdark: bool) -> None:
self.modules[y][x] = isdark
self.unmaskable[y][x] = True
def _add_ecc_and_interleave(self, data: bytearray) -> bytes:
ver: int = self.ver
assert len(data) == QrCode._get_num_data_codewords(ver, self.ecclvl)
# Calculate parameter numbers
numblocks: int = QrCode._NUM_ERROR_CORRECTION_BLOCKS[self.ecclvl.ordinal][ver]
blockecclen: int = QrCode._ECC_CODEWORDS_PER_BLOCK[self.ecclvl.ordinal][ver]
rawcodewords: int = QrCode._get_num_raw_data_modules(ver) // 8
numshortblocks: int = numblocks - rawcodewords % numblocks
shortblocklen: int = rawcodewords // numblocks
# Split data into blocks and append ECC to each block
blocks: List[bytes] = []
rsdiv: bytes = QrCode._reed_solomon_compute_divisor(blockecclen)
k: int = 0
for i in range(numblocks):
dat: bytearray = data[
k : k + shortblocklen - blockecclen + (0 if i < numshortblocks else 1)
]
k += len(dat)
ecc: bytes = QrCode._reed_solomon_compute_remainder(dat, rsdiv)
if i < numshortblocks:
dat.append(0)
blocks.append(dat + ecc)
assert k == len(data)
# Interleave (not concatenate) the bytes from every block into a single sequence
result = bytearray()
for i in range(len(blocks[0])):
for (j, blk) in enumerate(blocks):
# Skip the padding byte in short blocks
if (i != shortblocklen - blockecclen) or (j >= numshortblocks):
result.append(blk[i])
assert len(result) == rawcodewords
return result
def _draw_codewords(self, data: bytes) -> None:
assert len(data) == QrCode._get_num_raw_data_modules(self.ver) // 8
i: int = 0 # Bit index into the data
for right in range(self.size - 1, 0, -2):
# idx of right column in each column pair
if right <= 6:
right -= 1
for vert in range(self.size): # Vertical counter
for j in range(2):
x: int = right - j
upward: bool = (right + 1) & 2 == 0
y: int = (self.size - 1 - vert) if upward else vert
if (not self.unmaskable[y][x]) and (i < len(data) * 8):
self.modules[y][x] = _get_bit(data[i >> 3], 7 - (i & 7))
i += 1
# any remainder bits (0..7) were set 0/false/light by ctor
assert i == len(data) * 8
def _apply_mask(self, mask: int) -> None:
masker: Callable[[int, int], int] = QrCode._MASK_PATTERNS[mask]
for y in range(self.size):
for x in range(self.size):
self.modules[y][x] ^= (masker(x, y) == 0) and (
not self.unmaskable[y][x]
)
def _get_penalty_score(self) -> int:
result: int = 0
size: int = self.size
modules: List[List[bool]] = self.modules
# Adjacent modules in row having same color, and finder-like patterns
for y in range(size):
runcolor: bool = False
runx: int = 0
runhistory = collections.deque([0] * 7, 7)
for x in range(size):
if modules[y][x] == runcolor:
runx += 1
if runx == 5:
result += QrCode._PENALTY_N1
elif runx > 5:
result += 1
else:
self._finder_penalty_add_history(runx, runhistory)
if not runcolor:
result += (
self._finder_penalty_count_patterns(runhistory)
* QrCode._PENALTY_N3
)
runcolor = modules[y][x]
runx = 1
result += (
self._finder_penalty_terminate_and_count(runcolor, runx, runhistory)
* QrCode._PENALTY_N3
)
# Adjacent modules in column having same color, and finder-like patterns
for x in range(size):
runcolor = False
runy = 0
runhistory = collections.deque([0] * 7, 7)
for y in range(size):
if modules[y][x] == runcolor:
runy += 1
if runy == 5:
result += QrCode._PENALTY_N1
elif runy > 5:
result += 1
else:
self._finder_penalty_add_history(runy, runhistory)
if not runcolor:
result += (
self._finder_penalty_count_patterns(runhistory)
* QrCode._PENALTY_N3
)
runcolor = modules[y][x]
runy = 1
result += (
self._finder_penalty_terminate_and_count(runcolor, runy, runhistory)
* QrCode._PENALTY_N3
)
# 2*2 blocks of modules having same color
for y in range(size - 1):
for x in range(size - 1):
if (
modules[y][x]
== modules[y][x + 1]
== modules[y + 1][x]
== modules[y + 1][x + 1]
):
result += QrCode._PENALTY_N2
# Balance of dark and light modules
dark: int = sum((1 if cell else 0) for row in modules for cell in row)
total: int = size ** 2 # Note that size is odd, so dark/total != 1/2
# Compute the smallest integer k >= 0 such that (45-5k)% <= dark/total <= (55+5k)%
k: int = (abs(dark * 20 - total * 10) + total - 1) // total - 1
assert 0 <= k <= 9
result += k * QrCode._PENALTY_N4
assert 0 <= result <= 2568888
# ^ Non-tight upper bound based on default values of PENALTY_N1, ..., N4
return result
def _get_alignment_pattern_positions(self) -> List[int]:
ver: int = self.ver
if ver == 1:
return []
numalign: int = ver // 7 + 2
step: int = (
26
if (ver == 32)
else (ver * 4 + numalign * 2 + 1) // (numalign * 2 - 2) * 2
)
result: List[int] = [
(self.size - 7 - i * step) for i in range(numalign - 1)
] + [6]
return list(reversed(result))
@staticmethod
def _get_num_raw_data_modules(ver: int) -> int:
result: int = (16 * ver + 128) * ver + 64
if ver >= 2:
numalign: int = ver // 7 + 2
result -= (25 * numalign - 10) * numalign - 55
if ver >= 7:
result -= 36
assert 208 <= result <= 29648
return result
@staticmethod
def _get_num_data_codewords(ver: int, ecl: Ecc) -> int:
return (
QrCode._get_num_raw_data_modules(ver) // 8
- QrCode._ECC_CODEWORDS_PER_BLOCK[ecl.ordinal][ver]
* QrCode._NUM_ERROR_CORRECTION_BLOCKS[ecl.ordinal][ver]
)
@staticmethod
def _reed_solomon_compute_divisor(degree: int) -> bytes:
if not (1 <= degree <= 255):
raise ValueError("Degree out of range")
# Polynomial coefficients are stored from highest to lowest power, excluding the leading term which is always 1.
# For example the polynomial x^3 + 255x^2 + 8x + 93 is stored as the uint8 array [255, 8, 93].
result = bytearray([0] * (degree - 1) + [1]) # start with monomial x^0
# Compute the product polynomial (x - r^0) * (x - r^1) * (x - r^2) * ... * (x - r^{degree-1}),
# and drop the highest monomial term which is always 1x^degree.
# Note that r = 0x02, which is a generator element of this field GF(2^8/0x11D).
root: int = 1
for _ in range(degree):
# Multiply the current product by (x - r^i)
for j in range(degree):
result[j] = QrCode._reed_solomon_multiply(result[j], root)
if j + 1 < degree:
result[j] ^= result[j + 1]
root = QrCode._reed_solomon_multiply(root, 0x02)
return result
@staticmethod
def _reed_solomon_compute_remainder(data: bytes, divisor: bytes) -> bytes:
result = bytearray([0] * len(divisor))
for b in data: # Polynomial division
factor: int = b ^ result.pop(0)
result.append(0)
for (i, coef) in enumerate(divisor):
result[i] ^= QrCode._reed_solomon_multiply(coef, factor)
return result
@staticmethod
def _reed_solomon_multiply(x: int, y: int) -> int:
if (x >> 8 != 0) or (y >> 8 != 0):
raise ValueError("Byte out of range")
z: int = 0 # Russian peasant multiplication
for i in reversed(range(8)):
z = (z << 1) ^ ((z >> 7) * 0x11D)
z ^= ((y >> i) & 1) * x
assert z >> 8 == 0
return z
def _finder_penalty_count_patterns(self, runhistory: collections.deque[int]) -> int:
n: int = runhistory[1]
assert n <= self.size * 3
core: bool = (
n > 0
and (runhistory[2] == runhistory[4] == runhistory[5] == n)
and runhistory[3] == n * 3
)
return (
1 if (core and runhistory[0] >= n * 4 and runhistory[6] >= n) else 0
) + (1 if (core and runhistory[6] >= n * 4 and runhistory[0] >= n) else 0)
def _finder_penalty_terminate_and_count(
self,
currentruncolor: bool,
currentrunlength: int,
runhistory: collections.deque[int],
) -> int:
if currentruncolor: # Terminate dark run
self._finder_penalty_add_history(currentrunlength, runhistory)
currentrunlength = 0
currentrunlength += self.size # Add light border to final run
self._finder_penalty_add_history(currentrunlength, runhistory)
return self._finder_penalty_count_patterns(runhistory)
def _finder_penalty_add_history(
self, currentrunlength: int, runhistory: collections.deque[int]
) -> None:
if runhistory[0] == 0:
currentrunlength += self.size # Add light border to initial run
runhistory.appendleft(currentrunlength)
_PENALTY_N1: int = 3
_PENALTY_N2: int = 3
_PENALTY_N3: int = 40
_PENALTY_N4: int = 10
# fmt: off
_ECC_CODEWORDS_PER_BLOCK: Sequence[Sequence[int]] = (
(-1, 7, 10, 15, 20, 26, 18, 20, 24, 30, 18, 20, 24, 26, 30, 22, 24, 28, 30, 28, 28, 28, 28, 30, 30, 26, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30), # noqa: E241 # L
(-1, 10, 16, 26, 18, 24, 16, 18, 22, 22, 26, 30, 22, 22, 24, 24, 28, 28, 26, 26, 26, 26, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28), # noqa: E241 # M
(-1, 13, 22, 18, 26, 18, 24, 18, 22, 20, 24, 28, 26, 24, 20, 30, 24, 28, 28, 26, 30, 28, 30, 30, 30, 30, 28, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30), # noqa: E241 # Q
(-1, 17, 28, 22, 16, 22, 28, 26, 26, 24, 28, 24, 28, 22, 24, 24, 30, 28, 28, 26, 28, 30, 24, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30, 30)) # noqa: E241 # H
_NUM_ERROR_CORRECTION_BLOCKS: Sequence[Sequence[int]] = (
(-1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 4, 4, 6, 6, 6, 6, 7, 8, 8, 9, 9, 10, 12, 12, 12, 13, 14, 15, 16, 17, 18, 19, 19, 20, 21, 22, 24, 25), # noqa: E241 # L
(-1, 1, 1, 1, 2, 2, 4, 4, 4, 5, 5, 5, 8, 9, 9, 10, 10, 11, 13, 14, 16, 17, 17, 18, 20, 21, 23, 25, 26, 28, 29, 31, 33, 35, 37, 38, 40, 43, 45, 47, 49), # noqa: E241 # M
(-1, 1, 1, 2, 2, 4, 4, 6, 6, 8, 8, 8, 10, 12, 16, 12, 17, 16, 18, 21, 20, 23, 23, 25, 27, 29, 34, 34, 35, 38, 40, 43, 45, 48, 51, 53, 56, 59, 62, 65, 68), # noqa: E241 # Q
(-1, 1, 1, 2, 4, 4, 4, 5, 6, 8, 8, 11, 11, 16, 16, 18, 16, 19, 21, 25, 25, 25, 34, 30, 32, 35, 37, 40, 42, 45, 48, 51, 54, 57, 60, 63, 66, 70, 74, 77, 81)) # noqa: E241 # H
# fmt: on
_MASK_PATTERNS: Sequence[Callable[[int, int], int]] = (
(lambda x, y: (x + y) % 2),
(lambda x, y: y % 2),
(lambda x, y: x % 3),
(lambda x, y: (x + y) % 3),
(lambda x, y: (x // 3 + y // 2) % 2),
(lambda x, y: x * y % 2 + x * y % 3),
(lambda x, y: (x * y % 2 + x * y % 3) % 2),
(lambda x, y: ((x + y) % 2 + x * y % 3) % 2),
)
class _BitBuffer(list): # type: ignore
def append_bits(self, val: int, n: int) -> None:
if (n < 0) or (val >> n != 0):
raise ValueError("Value out of range")
self.extend(((val >> i) & 1) for i in reversed(range(n)))
def _get_bit(x: int, i: int) -> bool:
return (x >> i) & 1 != 0
class DataTooLongError(ValueError):
pass
def qr2svg(qr: QrCode, border: int) -> str:
parts: list[str] = []
for y in range(qr.size):
sy = border + y
for x in range(qr.size):
if qr.modules[y][x]:
parts.append("M%d,%dh1v1h-1z" % (border + x, sy))
t = """\
<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg" version="1.1" viewBox="0 0 {0} {0}" stroke="none">
<rect width="100%" height="100%" fill="#F7F7F7"/>
<path d="{1}" fill="#111111"/>
</svg>
"""
return t.format(qr.size + border * 2, " ".join(parts))