Commit 47e351a3 authored by Gerd Moellmann's avatar Gerd Moellmann

*** empty log message ***

parent d1d3c685
......@@ -1581,6 +1581,9 @@ functionality with aliases for the mldrag functions.
* Lisp changes made after edition 2.6 of the Emacs Lisp Manual,
(Display-related features are described in a page of their own below.)
** In image specifications, `:heuristic-mask' has been replaced
with the more general `:mask' property.
** A `?' can be used in a symbol name without escaping it with a
backslash.
......@@ -2998,20 +3001,56 @@ around an image.
`:algorithm ALGO'
Apply an image algorithm to the image before displaying it. ALGO must
be a symbol specifying the algorithm. Currently only `laplace' is
supported which applies a Laplace edge detection algorithm to an image
which is intended to display images "disabled."
Apply an image algorithm to the image before displaying it.
ALGO `laplace' or `emboss' means apply a Laplace or ``emboss''
edge-detection algorithm to the image.
ALGO `(edge-detection :matrix MATRIX :color-adjust ADJUST)' means
apply a general edge-detection algorithm. MATRIX must be either a
nine-element list or a nine-element vector of numbers. A pixel at
position x/y in the transformed image is computed from original pixels
around that position. MATRIX specifies, for each pixel in the
neighborhood of x/y, a factor with which that pixel will influence the
transformed pixel; element 0 specifies the factor for the pixel at
x-1/y-1, element 1 the factor for the pixel at x/y-1 etc. as shown
below.
(x-1/y-1 x/y-1 x+1/y-1
x-1/y x/y x+1/y
x-1/y+1 x/y+1 x+1/y+1)
The resulting pixel is computed from the color intensity of the color
resulting from summing up the RGB values of surrounding pixels,
multiplied by the specified factors, and dividing that sum by the sum
of the factors' absolute values.
Laplace edge-detection currently uses a matrix of
`:heuristic-mask BG'
(1 0 0
0 0 0
9 9 -1)
Emboss edge-detection uses a matrix of
( 2 -1 0
-1 0 1
0 1 -2)
`:mask MASK'
If MASK is `heuristic' or `(heuristic BG)', build a clipping mask for
the image, so that the background of a frame is visible behind the
image. If BG is not specified, or if BG is t, determine the
background color of the image by looking at the 4 corners of the
image, assuming the most frequently occuring color from the corners is
the background color of the image. Otherwise, BG must be a list `(RED
GREEN BLUE)' specifying the color to assume for the background of the
image.
If BG is not nil, build a clipping mask for the image, so that the
background of a frame is visible behind the image. If BG is t,
determine the background color of the image by looking at the 4
corners of the image, assuming the most frequently occuring color from
the corners is the background color of the image. Otherwise, BG must
be a list `(RED GREEN BLUE)' specifying the color to assume for the
background of the image.
If MASK is nil, remove a mask from the image, if it has one. Images
in some formats include a mask which can be removed by specifying
`:mask nil'.
`:file FILE'
......
2000-09-15 Gerd Moellmann <gerd@gnu.org>
* image.el (create-image): Doc fix.
* toolbar/toolbar.el (toolbar-add-item): Use `:mask heuristic'
instead of `:heuristic-mask t'.
2000-09-14 Andrew Innes <andrewi@gnu.org>
* makefile.w32-in: Revert to Unix line endings.
......
2000-09-15 Gerd Moellmann <gerd@gnu.org>
* xfns.c (QCmatrix, QCcolor_adjustment, QCmask, Qemboss)
(Qedge_detection, Qheuristic): New symbols.
(syms_of_xfns): Initialize new symbols.
(lookup_image): Handle `:mask X', `:algorithm emboss', and
`algorithm (edge-detection ...)'.
(xbm_format, xpm_format, pbm_format, png_format, jpeg_format):
(tiff_format, gif_format, gs_format): Add `:mask'.
(XBM_MASK, XPM_MASK, PBM_MASK, PNG_MASK, JPEG_MASK, TIFF_MASK)
(GIF_MASK, GS_MASK): New enumerators.
(x_laplace_read_row, x_laplace_write_row): Functions removed.
(emboss_matrix, laplace_matrix): New variables.
(x_to_xcolors, x_from_xcolors, x_detect_edges, x_emboss)
(x_edge_detection): New functions.
(x_laplace): Rewritten in terms of x_detect_edges.
(x_build_heuristic_mask): If image has a mask, free it.
2000-09-14 Andrew Innes <andrewi@gnu.org>
* makefile.w32-in: Revert to Unix line endings.
......
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