The continuous-tone test asked whether 8 colors leave more than a tenth
of the error of one color. A gray picture's tones lie along one line,
where 8 colors come nearer to them, so some gray photos scored 0.078 to
0.093 and were traced as flat art, without the smoothing color photos
get. Their noise then mixed neighboring tones (a 16 Colors trace could
keep 10 or 12 colors) and stepped the edges.
A picture with at least 95% of its opaque pixels within 8 levels across
their channels now also counts as continuous tone when 8 colors leave
more than 0.065 of the error of one color, unless 16 colors leave at
most a fifth of the error of 8. These are VectorCraft's own values. The
exception keeps gray flat art of up to 16 clean levels on its old
route. Pictures with more than 5% of their opaque pixels outside that
8-level range are unchanged.
Anti-aliased or noisy gray flat art can now take the smoothed route as
well. Very noisy gray scans of flat art get fewer specks and staircase
edges; some gray illustrations and sketches get more anchors and
staircase edges at 16 Colors and High Fidelity Photo. Some 16 Colors
and High Fidelity Photo palettes of gray photos grow toward the
requested count, with more anchors and regions, and some 6 Colors
traces get more staircase edges.
A new built-in add-on, Image Tools (Object › Plug-ins › Image Tools),
adds Remove Background… (`addon.image.removeBackground`). It makes the
background of the selected images transparent by lowering the alpha of
their own pixels, in one undo step, with no service or model. The
background is the most common color along the image's edges, the
average of the image's corners, or colors the user picks. Contiguous
(on by default) clears it only where it reaches in from an edge; off,
it is cleared wherever it is. Tolerance and Softness (0 to 100, 10 by
default) set how near a color must be to be cleared and the band over
which pixels fade out. Match measures that nearness as the RGB
distance or as the largest difference on one channel. It is a
VectorCraft addition.
- The image stays an image: an embedded PNG with alpha, the source's
ICC profile and resolution, and 16 bits or gray when the source is.
A linked image is embedded and keeps its Placement Options.
- When the edges hold at least as many clear pixels as pixels of their
most common color, edge mode clears nothing, so a second run leaves
the subject alone. Corner mode leaves clear corners out of the
average and clears nothing when all four are clear.
- With Match set to Each Channel, a tolerance of t / 255 × 100 clears
the colors within t 8-bit steps on every channel.
- A CMYK image, a linked image that shows its preview, an image that
would need more than the decode allowance (checked from its header)
and a result with no pixel left are refused, and the document stays
as it was. When no pixel changes, no undo step is added. The result
reports `cleared`, the pixels made fully clear.
- Picked colors are hex colors, with or without `#`, or black, white,
red, green or blue.
- The dialog opens with Preview off; with Preview on, the canvas shows
the result, and Cancel puts the image back. While the dialog
previews, the session keeps the images' decoded pixels (at most
128 MiB, 32 MiB in the web app) so each preview step does not decode
them again, and releases them when the dialog closes with OK or
Cancel. A run that is not a preview step keeps nothing.
Docs: docs/mcp.md (Image Tools add-on), docs/target-app-parity.md.
A literal makes an extensible object whose properties are writable and
configurable, and an array whose length is writable. toSource wrote a
property defined with writable or configurable false, a sealed, frozen or
non-extensible object or array, and an array with a read-only length as an
ordinary literal, so evaluating the text gave an open value.
toSource now throws a TypeError for each of these, at any depth, as it
already does for getters, hidden properties and other prototypes.
Properties defined with every flag on are written as before.