First public commit.

lenser/c16/convert/mono.py

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+"""C16 TED monochrome: 320x200, restricted to the TED's neutral grey ramp (8
+luminance levels of hue 1, plus black) for smooth greyscale.  ``--mono-base``
+tints it toward one hue (black -> hue -> white).  Two greys per 8x8 cell, packed
+into the same TED hires layout as the colour mode."""
+from __future__ import annotations
+
+import numpy as np
+
+from ...convert import base
+from .. import palette as tedpal
+from . import hires
+
+WIDTH, HEIGHT = hires.WIDTH, hires.HEIGHT
+CELL_W, CELL_H = hires.CELL_W, hires.CELL_H
+PIXEL_ASPECT = hires.PIXEL_ASPECT
+
+
+def convert(img_rgb, palette_name="ted", dither_mode="floyd",
+            intensive=False, base_color=None):
+    plab = tedpal.palette_lab()
+    prgb = tedpal.get_palette().astype(np.uint8)
+
+    ramp = base.luminance_ramp(plab, tedpal.GREYS, base_color)
+    idx, sets, rows, cols, err = base.mono_render(
+        img_rgb, plab, ramp, WIDTH, HEIGHT, CELL_W, CELL_H, dither_mode, n_free=2)
+
+    bitmap, attr, ch = hires._encode(idx, sets, rows, cols)
+    payload = bytes(bitmap) + bytes(attr) + bytes(ch)
+
+    return base.Conversion(
+        mode="mono", width=WIDTH, height=HEIGHT, pixel_aspect=PIXEL_ASPECT,
+        index_image=idx.astype(np.uint16), data=payload, viewer="c16",
+        preview_rgb=prgb[idx], error=err,
+        meta={"palette": "ted", "dither": dither_mode, "border": 0},
+    )