mirror of
https://github.com/KrisKennaway/ii-vision.git
synced 2025-07-18 11:24:21 +00:00
Checkpoint WIP for easier comparison to dhgr branch:
- naive version of NTSC artifacting, it uses a sliding 4-bit window to assign a nominal (D)HGR colour to each dot position. A more sophisticated/correct implementation would model the YIQ signal directly. - Switch DHGRBitmap implementation to use a 34-bit representation of the 4-byte tuple, comprised of a 3-bit header and footer, plus 4*7=28-bit body. The headers/footers account for the influence on neighbouring tuples from the 4-bit NTSC window. - With this model each screen byte influences 13 pixels, so we need to precompute 2^26 edit distances for all possible (source, target) 13-bit sequences. - Checkpointing not-yet-working HGR implementation. - Add new unit tests but not yet all passing due to refactoring
This commit is contained in:
kris
@@ -3,10 +3,11 @@
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import bz2
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import functools
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import pickle
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from typing import Union, List
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from typing import Union, List, Optional
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import numpy as np
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import palette
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import palette as pal
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# Type annotation for cases where we may process either an int or a numpy array.
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IntOrArray = Union[int, np.ndarray]
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@@ -124,55 +125,334 @@ class MemoryMap:
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self.page_offset[page - self._page_start][offset] = val
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class DHGRBitmap:
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BYTE_MASK32 = [
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# 3333333222222211111110000000 <- byte 0.3
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#
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# 33222222222211111111110000000000 <- bit pos in uint32
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# 10987654321098765432109876543210
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# 0000GGGGFFFFEEEEDDDDCCCCBBBBAAAA <- pixel A..G
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# 3210321032103210321032103210 <- bit pos in A..G pixel
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0b00000000000000000000000011111111, # byte 0 influences A,B
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0b00000000000000001111111111110000, # byte 1 influences B,C,D
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0b00000000111111111111000000000000, # byte 2 influences D,E,F
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0b00001111111100000000000000000000, # byte 3 influences F,G
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]
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@functools.lru_cache(None)
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def _edit_distances(name: str, palette_id: pal.Palette) -> List[np.ndarray]:
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"""Load edit distance matrices for masked, shifted byte values.
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# How much to right-shift bits after masking to bring into int8/int12 range
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BYTE_SHIFTS = [0, 4, 12, 20]
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This is defined at module level to be a singleton.
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"""
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data = "transcoder/data/%s_palette_%d_edit_distance.pickle.bz2" % (
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name,
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palette_id.value
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)
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with bz2.open(data, "rb") as ed:
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return pickle.load(ed) # type: List[np.ndarray]
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@staticmethod
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@functools.lru_cache(None)
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def edit_distances(palette_id: palette.Palette) -> List[np.ndarray]:
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"""Load edit distance matrices for masked, shifted byte 0..3 values."""
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data = "transcoder/data/palette_%d_edit_distance.pickle.bz2" % (
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palette_id.value
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)
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with bz2.open(data, "rb") as ed:
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return pickle.load(ed) # type: List[np.ndarray]
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def __init__(self, main_memory: MemoryMap, aux_memory: MemoryMap):
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self.main_memory = main_memory
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self.aux_memory = aux_memory
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class Bitmap:
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"""Packed 28-bit bitmap representation of (D)HGR screen memory.
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self.packed = np.empty(shape=(32, 128), dtype=np.uint32)
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The memory layout is still page-oriented, not linear y-x buffer but the
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bit map is such that 20 consecutive entries linearly encode the 28*20 =
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560-bit monochrome dot positions that underlie both Mono and Colour (
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D)HGR screens.
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For Colour display the (nominal) colours are encoded as 4-bit pixels.
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"""
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def __init__(
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self,
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palette: pal.Palette,
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main_memory: MemoryMap,
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aux_memory: Optional[MemoryMap]
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):
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self.palette = palette # type: pal.Palette
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self.main_memory = main_memory # type: MemoryMap
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self.aux_memory = aux_memory # type: Optional[MemoryMap]
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self.packed = np.empty(
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shape=(32, 128), dtype=np.uint64) # type: np.ndarray
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self._pack()
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def _pack(self) -> None:
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"""Interleave and pack aux and main memory into 28-bit uint32 array"""
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"""Pack MemoryMap into 34-bit representation."""
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raise NotImplementedError
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NAME = None
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@functools.lru_cache(None)
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def edit_distances(self, palette_id: pal.Palette) -> List[np.ndarray]:
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"""Load edit distance matrices for masked, shifted byte values."""
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return _edit_distances(self.NAME, palette_id)
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def apply(
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self,
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page: int,
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offset: np.uint8,
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is_aux: bool,
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value: np.uint8) -> None:
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raise NotImplementedError
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@functools.lru_cache(None)
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def byte_pair_difference(
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self,
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byte_offset: int,
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old_packed: int,
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content: int
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) -> int:
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raise NotImplementedError
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def diff_weights(
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self,
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other: "DHGRBitmap",
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is_aux: bool
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) -> np.ndarray:
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raise NotImplementedError
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def compute_delta(
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self,
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content: int,
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old: np.ndarray,
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is_aux: bool
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) -> np.ndarray:
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raise NotImplementedError
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class HGRBitmap(Bitmap):
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BYTE_MASK16 = [
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# 11111110000000 <- byte 0, 1
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# 1111110000000000
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# 5432109876543210
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# 00GGFFEEDDCCBBAA <- pixel A..G
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0b0000000011111111,
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0b0011111111000000
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]
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# Representation
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#
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# 1111110000000000
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# 5432109876543210
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# PGGFFEEDPDCCBBAA
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#
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# Where palette bit influences all of the pixels in the byte
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#
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# Map to 3-bit pixels, i.e. 21-bit quantity
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#
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# 222211111111110000000000
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# 321098765432109876543210
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# 000PGGPFFPEEPDDPCCPBBPAA
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BYTE_MASK32 = [
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0b000000000000111111111111,
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0b000111111111111000000000
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]
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# XXX 3-bit pixel isn't quite correct, e.g. the case of conflicting
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# palette bits across byte boundary
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# Also hard to interleave the palette bit in multiple places - could use
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# a mapping array but maybe don't need to, can just use 8-bit values as is?
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# But need contiguous representation for edit distance tables
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# P
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# (0)00 --> 0.0.
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# (0)01 --> 0.1.
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#
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# (1)01 --> .0.1
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# (1)11 --> .1.1
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# etc
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#
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BYTE_SHIFTS = [0, 9]
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NAME = 'HGR'
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def __init__(self, palette: pal.Palette, main_memory: MemoryMap):
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super(HGRBitmap, self).__init__(palette, main_memory, None)
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def _pack(self) -> None:
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"""Pack main memory into (28+3)-bit uint64 array"""
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# 00000000001111111111222222222233
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# 01234567890123456789012345678901
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# AAAABBBBCCCCDDd
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# AAAABBBBCCCCDd
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# DDEEEEFFFFGGGGg
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# dDDEEEEFFFFGGGg
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# Even, P0: store unshifted (0..14)
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# Even, P1: store shifted << 1 (1..15) (only need 1..14)
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# Odd, P0: store shifted << 14 (14 .. 28) - set bit 14 as bit 0 of next
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# byte
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# Odd, p1: store shifted << 15 (15 .. 29) (only need 15 .. 28) - set
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# bit 13 as bit 0 of next byte
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# Odd overflow only matters for even, P1
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# - bit 0 is either bit 14 if odd, P0 or bit 13 if odd, P1
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# - but these both come from the undoubled bit 6.
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main = self.main_memory.page_offset.astype(np.uint64)
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# Double 7-bit pixel data from a into 14-bit fat pixels, and extend MSB
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# into 15-bits tohandle case when subsequent byte has palette bit set,
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# i.e. is right-shifted by 1 dot. This only matters for even bytes
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# with P=0 that are followed by odd bytes with P=1; in other cases
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# this extra bit will be overwritten.
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double = (
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# Bit pos 6
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((main & 0x40) << 8) + ((main & 0x40) << 7) + (
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(main & 0x40) << 6)) + (
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# Bit pos 5
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((main & 0x20) << 6) + ((main & 0x20) << 5)) + (
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# Bit pos 4
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((main & 0x10) << 5) + ((main & 0x10) << 4)) + (
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# Bit pos 3
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((main & 0x08) << 4) + ((main & 0x08) << 3)) + (
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# Bit pos 2
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((main & 0x04) << 3) + ((main & 0x04) << 2)) + (
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# Bit pos 1
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((main & 0x02) << 2) + ((main & 0x02) << 1)) + (
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# Bit pos 0
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((main & 0x01) << 1) + (main & 0x01))
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a_even = main[:, ::2]
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a_odd = main[:, 1::2]
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double_even = double[:, ::2]
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double_odd = double[:, 1::2]
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# Place even offsets at bits 1..15 (P=1) or 0..14 (P=0)
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packed = np.where(a_even & 0x80, double_even << 1, double_even)
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# Place off offsets at bits 15..27 (P=1) or 14..27 (P=0)
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packed = np.where(
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a_odd & 0x80,
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np.bitwise_xor(
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np.bitwise_and(packed, (2 ** 15 - 1)),
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double_odd << 15
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),
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np.bitwise_xor(
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np.bitwise_and(packed, (2 ** 14 - 1)),
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double_odd << 14
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)
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)
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# Patch up even offsets with P=1 with extended bit from previous odd
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# column
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previous_odd = np.roll(a_odd, 1, axis=1).astype(np.uint64)
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packed = np.where(
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a_even & 0x80,
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# Truncate to 28-bits and set bit 0 from bit 6 of previous byte
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np.bitwise_xor(
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np.bitwise_and(packed, (2 ** 28 - 2)),
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(previous_odd & (1 << 6)) >> 6
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),
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# Truncate to 28-bits
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np.bitwise_and(packed, (2 ** 28 - 1))
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)
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# Append first 3 bits of next even byte so we can correctly
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# decode the effective colours at the end of the 28-bit tuple
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trailing = np.roll(packed, -1, axis=1).astype(np.uint64)
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packed = np.bitwise_xor(
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packed,
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(trailing & 0b111) << 28
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)
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self.packed = packed
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@staticmethod
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@functools.lru_cache(None)
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def byte_offset(x_byte: int) -> int:
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"""Returns 0..1 offset in ByteTuple for a given x_byte,"""
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is_odd = x_byte % 2 == 1
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return 1 if is_odd else 0
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@staticmethod
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def masked_update(
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byte_offset: int,
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old_value: IntOrArray,
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new_value: int) -> IntOrArray:
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raise NotImplementedError
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def apply(self, page: int, offset: int, is_aux: bool, value: int) -> None:
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"""Update packed representation of changing main/aux memory."""
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assert not is_aux
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# XXX fix
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byte_offset = self.byte_offset(offset)
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packed_offset = offset // 2
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self.packed[page, packed_offset] = self.masked_update(
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byte_offset, self.packed[page, packed_offset], value)
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# XXXX Generic?
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def mask_and_shift_data(
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self,
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data: IntOrArray,
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byte_offset: int) -> IntOrArray:
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"""Masks and shifts data into the 8 or 12-bit range."""
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return (data & self.BYTE_MASK32[byte_offset]) >> (
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self.BYTE_SHIFTS[byte_offset])
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class DHGRBitmap(Bitmap):
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# NOTE: See https://github.com/numpy/numpy/issues/2524 and related issues
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# for why we have to cast things explicitly to np.uint64 - type promotion
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# to uint64 is broken in numpy :(
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# 3-bit header + 28-bit body + 3-bit trailer
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BYTE_MASK34 = [
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# 3333333222222211111110000000 <- byte 0.3
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#
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# 3333222222222211111111110000000000 <- bit pos in uint64
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# 3210987654321098765432109876543210
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# tttGGGGFFFFEEEEDDDDCCCCBBBBAAAAhhh <- pixel A..G
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# 3210321032103210321032103210 <- bit pos in A..G pixel
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np.uint64(0b0000000000000000000001111111111111), # byte 0 int13 mask
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np.uint64(0b0000000000000011111111111110000000), # byte 1 int13 mask
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np.uint64(0b0000000111111111111100000000000000), # byte 2 int13 mask
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np.uint64(0b1111111111111000000000000000000000), # byte 3 int13 mask
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]
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# How much to right-shift bits after masking to bring into int13 range
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BYTE_SHIFTS = [np.uint64(0), np.uint64(7), np.uint64(14), np.uint64(21)]
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NAME = 'DHGR'
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def _pack(self) -> None:
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"""Interleave and pack aux and main memory into 34-bit uint64 array"""
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# Palette bit is unused for DHGR so mask it out
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aux = (self.aux_memory.page_offset & 0x7f).astype(np.uint32)
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main = (self.main_memory.page_offset & 0x7f).astype(np.uint32)
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aux = (self.aux_memory.page_offset & 0x7f).astype(np.uint64)
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main = (self.main_memory.page_offset & 0x7f).astype(np.uint64)
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# Interleave aux and main memory columns and pack 7-bit masked values
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# into a 28-bit value. This sequentially encodes 7 4-bit DHGR pixels.
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# into a 28-bit value, with 3-bit header and trailer. This
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# sequentially encodes 7 4-bit DHGR pixels, together with the
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# neighbouring 3 bits that are necessary to decode artifact colours.
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#
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# See make_data_tables.py for more discussion about this representation.
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self.packed = (
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aux[:, 0::2] +
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(main[:, 0::2] << 7) +
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(aux[:, 1::2] << 14) +
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(main[:, 1::2] << 21)
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packed = (
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(aux[:, 0::2] << 3) +
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(main[:, 0::2] << 10) +
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(aux[:, 1::2] << 17) +
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(main[:, 1::2] << 24)
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)
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# Prepend last 3 bits of previous main odd byte so we can correctly
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# decode the effective colours at the beginning of the 28-bit
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# tuple
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prevcol = np.roll(packed, 1, axis=1).astype(np.uint64)
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# Append first 3 bits of next aux even byte so we can correctly
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# decode the effective colours at the end of the 28-bit tuple
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nextcol = np.roll(packed, -1, axis=1).astype(np.uint64)
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self.packed = np.bitwise_xor(
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np.bitwise_xor(
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packed,
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# Prepend last 3 bits of 28-bit body from previous column
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(prevcol & (0b111 << 28)) >> 28
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),
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# Append first 3 bits of 28-bit body from next column
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(nextcol & (0b111 << 3)) << 28
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)
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|
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@staticmethod
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@@ -190,31 +470,207 @@ class DHGRBitmap:
|
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else:
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return 1
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|
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# XXX test
|
||||
@staticmethod
|
||||
def masked_update(
|
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def masked_update_scalar(
|
||||
byte_offset: int,
|
||||
old_value: IntOrArray,
|
||||
new_value: int) -> IntOrArray:
|
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old_value: np.uint64,
|
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new_value: np.uint8) -> np.uint64:
|
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# Mask out 7-bit value where update will go
|
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masked_value = old_value & ~(0x7f << (7 * byte_offset))
|
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masked_value = old_value & (
|
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~np.uint64(0x7f << (7 * byte_offset + 3)))
|
||||
|
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update = (new_value & 0x7f) << (7 * byte_offset)
|
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update = (new_value & np.uint64(0x7f)) << np.uint64(
|
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7 * byte_offset + 3)
|
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|
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return masked_value ^ update
|
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new = masked_value ^ update
|
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return new
|
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|
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def apply(self, page: int, offset: int, is_aux: bool, value: int) -> None:
|
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# XXX test
|
||||
@staticmethod
|
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def masked_update_array(
|
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byte_offset: int,
|
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old_value: np.ndarray,
|
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new_value: int) -> np.ndarray:
|
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# Mask out 7-bit value where update will go
|
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masked_value = old_value & (
|
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~np.uint64(0x7f << (7 * byte_offset + 3)))
|
||||
|
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update = (new_value & np.uint64(0x7f)) << np.uint64(7 * byte_offset + 3)
|
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|
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new = masked_value ^ update
|
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|
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# TODO: don't leak headers across screen rows.
|
||||
|
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if byte_offset == 0:
|
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# Need to also update the 3-bit trailer of the preceding column
|
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|
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shifted = np.roll(new, -1, axis=1)
|
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|
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new &= np.uint64(2 ** 31 - 1)
|
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new ^= (shifted & np.uint64(0b111 << 3)) << np.uint64(28)
|
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elif byte_offset == 3:
|
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# Need to also update the 3-bit header of the next column
|
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|
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shifted = np.roll(new, 1, axis=1)
|
||||
|
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new &= np.uint64((2 ** 31 - 1) << 3)
|
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new ^= (shifted & np.uint64(0b111 << 28)) >> np.uint64(28)
|
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return new
|
||||
|
||||
# XXX test
|
||||
def apply(
|
||||
self,
|
||||
page: int,
|
||||
offset: int,
|
||||
is_aux: bool,
|
||||
value: np.uint8) -> None:
|
||||
"""Update packed representation of changing main/aux memory."""
|
||||
|
||||
byte_offset = self.interleaved_byte_offset(offset, is_aux)
|
||||
packed_offset = offset // 2
|
||||
|
||||
self.packed[page, packed_offset] = self.masked_update(
|
||||
self.packed[page, packed_offset] = self.masked_update_scalar(
|
||||
byte_offset, self.packed[page, packed_offset], value)
|
||||
|
||||
# TODO: don't leak headers/trailers across screen rows.
|
||||
if byte_offset == 0 and packed_offset > 0:
|
||||
# Need to also update the 3-bit trailer of the preceding column
|
||||
self.packed[page, packed_offset - 1] &= np.uint64(2 ** 31 - 1)
|
||||
|
||||
self.packed[page, packed_offset - 1] ^= (
|
||||
(self.packed[page, packed_offset] & np.uint64(0b111 << 3))
|
||||
<< np.uint64(28)
|
||||
)
|
||||
elif byte_offset == 3 and packed_offset < 127:
|
||||
# Need to also update the 3-bit header of the next column
|
||||
self.packed[page, packed_offset + 1] &= np.uint64(
|
||||
(2 ** 31 - 1) << 3)
|
||||
|
||||
self.packed[page, packed_offset + 1] ^= (
|
||||
(self.packed[page, packed_offset] & np.uint64(0b111 << 28))
|
||||
>> np.uint64(28)
|
||||
)
|
||||
|
||||
def mask_and_shift_data(
|
||||
self,
|
||||
data: IntOrArray,
|
||||
byte_offset: int) -> IntOrArray:
|
||||
"""Masks and shifts data into the 8 or 12-bit range."""
|
||||
return (data & self.BYTE_MASK32[byte_offset]) >> (
|
||||
"""Masks and shifts data into the 13-bit range."""
|
||||
res = (data & self.BYTE_MASK34[byte_offset]) >> (
|
||||
self.BYTE_SHIFTS[byte_offset])
|
||||
assert np.all(res <= 2 ** 13)
|
||||
return res
|
||||
|
||||
@functools.lru_cache(None)
|
||||
def byte_pair_difference(
|
||||
self,
|
||||
byte_offset: int,
|
||||
old_packed: np.uint64,
|
||||
content: np.uint8
|
||||
) -> int:
|
||||
|
||||
old_pixels = self.mask_and_shift_data(
|
||||
old_packed, byte_offset)
|
||||
new_pixels = self.mask_and_shift_data(
|
||||
self.masked_update_scalar(
|
||||
byte_offset, old_packed, content), byte_offset)
|
||||
|
||||
pair = (old_pixels << np.uint64(13)) + new_pixels
|
||||
|
||||
return self.edit_distances(self.palette)[byte_offset][pair]
|
||||
|
||||
def diff_weights(
|
||||
self,
|
||||
source: "DHGRBitmap",
|
||||
is_aux: bool
|
||||
) -> np.ndarray:
|
||||
return self._diff_weights(source.packed, is_aux)
|
||||
|
||||
def _diff_weights(
|
||||
self,
|
||||
source_packed: np.ndarray,
|
||||
is_aux: bool
|
||||
) -> np.ndarray:
|
||||
"""Computes diff from source_packed to self.packed"""
|
||||
diff = np.ndarray((32, 256), dtype=np.int)
|
||||
|
||||
if is_aux:
|
||||
offsets = [0, 2]
|
||||
else:
|
||||
offsets = [1, 3]
|
||||
|
||||
dists = []
|
||||
for o in offsets:
|
||||
# Pixels influenced by byte offset o
|
||||
source_pixels = self.mask_and_shift_data(source_packed, o)
|
||||
target_pixels = self.mask_and_shift_data(self.packed, o)
|
||||
|
||||
# Concatenate 13-bit source and target into 26-bit values
|
||||
pair = (source_pixels << np.uint64(13)) + target_pixels
|
||||
dist = self.edit_distances(self.palette)[o][pair].reshape(
|
||||
pair.shape)
|
||||
dists.append(dist)
|
||||
|
||||
diff[:, 0::2] = dists[0]
|
||||
diff[:, 1::2] = dists[1]
|
||||
|
||||
return diff
|
||||
|
||||
def compute_delta(
|
||||
self,
|
||||
content: int,
|
||||
old: np.ndarray,
|
||||
is_aux: bool
|
||||
) -> np.ndarray:
|
||||
# TODO: use error edit distance
|
||||
|
||||
# XXX reuse code
|
||||
|
||||
diff = np.ndarray((32, 256), dtype=np.int)
|
||||
|
||||
if is_aux:
|
||||
# Pixels influenced by byte offset 0
|
||||
source_pixels0 = self.mask_and_shift_data(
|
||||
self.masked_update_array(0, self.packed, content), 0)
|
||||
target_pixels0 = self.mask_and_shift_data(self.packed, 0)
|
||||
|
||||
# Concatenate 13-bit source and target into 26-bit values
|
||||
pair0 = (source_pixels0 << np.uint64(13)) + target_pixels0
|
||||
dist0 = self.edit_distances(self.palette)[0][pair0].reshape(
|
||||
pair0.shape)
|
||||
|
||||
# Pixels influenced by byte offset 2
|
||||
source_pixels2 = self.mask_and_shift_data(
|
||||
self.masked_update_array(2, self.packed, content), 2)
|
||||
target_pixels2 = self.mask_and_shift_data(self.packed, 2)
|
||||
# Concatenate 13-bit source and target into 26-bit values
|
||||
pair2 = (source_pixels2 << np.uint64(13)) + target_pixels2
|
||||
dist2 = self.edit_distances(self.palette)[2][pair2].reshape(
|
||||
pair2.shape)
|
||||
|
||||
diff[:, 0::2] = dist0
|
||||
diff[:, 1::2] = dist2
|
||||
|
||||
else:
|
||||
# Pixels influenced by byte offset 1
|
||||
source_pixels1 = self.mask_and_shift_data(
|
||||
self.masked_update_array(1, self.packed, content), 1)
|
||||
target_pixels1 = self.mask_and_shift_data(self.packed, 1)
|
||||
pair1 = (source_pixels1 << np.uint64(13)) + target_pixels1
|
||||
dist1 = self.edit_distances(self.palette)[1][pair1].reshape(
|
||||
pair1.shape)
|
||||
|
||||
# Pixels influenced by byte offset 3
|
||||
source_pixels3 = self.mask_and_shift_data(
|
||||
self.masked_update_array(3, self.packed, content), 3)
|
||||
target_pixels3 = self.mask_and_shift_data(self.packed, 3)
|
||||
pair3 = (source_pixels3 << np.uint64(13)) + target_pixels3
|
||||
dist3 = self.edit_distances(self.palette)[3][pair3].reshape(
|
||||
pair3.shape)
|
||||
|
||||
diff[:, 0::2] = dist1
|
||||
diff[:, 1::2] = dist3
|
||||
|
||||
# TODO: try different weightings
|
||||
return (diff * 5) - old
|
||||
|
||||
Reference in New Issue
Block a user