;;; image.el --- image API
;; Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003,
-;; 2004, 2005 Free Software Foundation, Inc.
+;; 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
;; Maintainer: FSF
;; Keywords: multimedia
;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 2, or (at your option)
+;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
:group 'multimedia)
-(defconst image-type-regexps
+(defconst image-type-header-regexps
'(("\\`/[\t\n\r ]*\\*.*XPM.\\*/" . xpm)
- ("\\`P[1-6]" . pbm)
- ("\\`GIF8" . gif)
- ("\\`\211PNG\r\n" . png)
- ("\\`[\t\n\r ]*#define" . xbm)
- ("\\`\\(MM\0\\*\\|II\\*\0\\)" . tiff)
+ ("\\`P[1-6][[:space:]]+\\(?:#.*[[:space:]]+\\)*[0-9]+[[:space:]]+[0-9]+" . pbm)
+ ("\\`GIF8[79]a" . gif)
+ ("\\`\x89PNG\r\n\x1a\n" . png)
+ ("\\`[\t\n\r ]*#define \\([a-z0-9]+\\)_width [0-9]+\n\
+#define \\1_height [0-9]+\n\
+static char \\1_bits" . xbm)
+ ("\\`\\(?:MM\0\\*\\|II\\*\0\\)" . tiff)
("\\`[\t\n\r ]*%!PS" . postscript)
("\\`\xff\xd8" . (image-jpeg-p . jpeg)))
"Alist of (REGEXP . IMAGE-TYPE) pairs used to auto-detect image types.
with one argument, a string containing the image data. If PREDICATE returns
a non-nil value, TYPE is the image's type.")
-(defvar image-load-path
- (list (file-name-as-directory (expand-file-name "images" data-directory))
- 'data-directory 'load-path)
+(defconst image-type-file-name-regexps
+ '(("\\.png\\'" . png)
+ ("\\.gif\\'" . gif)
+ ("\\.jpe?g\\'" . jpeg)
+ ("\\.bmp\\'" . bmp)
+ ("\\.xpm\\'" . xpm)
+ ("\\.pbm\\'" . pbm)
+ ("\\.xbm\\'" . xbm)
+ ("\\.ps\\'" . postscript)
+ ("\\.tiff?\\'" . tiff))
+ "Alist of (REGEXP . IMAGE-TYPE) pairs used to identify image files.
+When the name of an image file match REGEXP, it is assumed to
+be of image type IMAGE-TYPE.")
+
+;; We rely on `auto-mode-alist' to detect xbm and xpm files, instead
+;; of content autodetection. Their contents are just C code, so it is
+;; easy to generate false matches.
+(defvar image-type-auto-detectable
+ '((pbm . t)
+ (xbm . nil)
+ (bmp . maybe)
+ (gif . maybe)
+ (png . maybe)
+ (xpm . nil)
+ (jpeg . maybe)
+ (tiff . maybe)
+ (postscript . nil))
+ "Alist of (IMAGE-TYPE . AUTODETECT) pairs used to auto-detect image files.
+\(See `image-type-auto-detected-p').
+
+AUTODETECT can be
+ - t always auto-detect.
+ - nil never auto-detect.
+ - maybe auto-detect only if the image type is available
+ (see `image-type-available-p').")
+
+(defvar image-load-path nil
"List of locations in which to search for image files.
If an element is a string, it defines a directory to search.
If an element is a variable symbol whose value is a string, that
If an element is a variable symbol whose value is a list, the
value is used as a list of directories to search.")
+(eval-at-startup
+ (setq image-load-path
+ (list (file-name-as-directory (expand-file-name "images" data-directory))
+ 'data-directory 'load-path)))
+
+
+(defun image-load-path-for-library (library image &optional path no-error)
+ "Return a suitable search path for images used by LIBRARY.
+
+It searches for IMAGE in `image-load-path' (excluding
+\"`data-directory'/images\") and `load-path', followed by a path
+suitable for LIBRARY, which includes \"../../etc/images\" and
+\"../etc/images\" relative to the library file itself, and then
+in \"`data-directory'/images\".
+
+Then this function returns a list of directories which contains
+first the directory in which IMAGE was found, followed by the
+value of `load-path'. If PATH is given, it is used instead of
+`load-path'.
+
+If NO-ERROR is non-nil and a suitable path can't be found, don't
+signal an error. Instead, return a list of directories as before,
+except that nil appears in place of the image directory.
+
+Here is an example that uses a common idiom to provide
+compatibility with versions of Emacs that lack the variable
+`image-load-path':
+
+ ;; Shush compiler.
+ (defvar image-load-path)
+
+ (let* ((load-path (image-load-path-for-library \"mh-e\" \"mh-logo.xpm\"))
+ (image-load-path (cons (car load-path)
+ (when (boundp 'image-load-path)
+ image-load-path))))
+ (mh-tool-bar-folder-buttons-init))"
+ (unless library (error "No library specified"))
+ (unless image (error "No image specified"))
+ (let (image-directory image-directory-load-path)
+ ;; Check for images in image-load-path or load-path.
+ (let ((img image)
+ (dir (or
+ ;; Images in image-load-path.
+ (image-search-load-path image)
+ ;; Images in load-path.
+ (locate-library image)))
+ parent)
+ ;; Since the image might be in a nested directory (for
+ ;; example, mail/attach.pbm), adjust `image-directory'
+ ;; accordingly.
+ (when dir
+ (setq dir (file-name-directory dir))
+ (while (setq parent (file-name-directory img))
+ (setq img (directory-file-name parent)
+ dir (expand-file-name "../" dir))))
+ (setq image-directory-load-path dir))
+
+ ;; If `image-directory-load-path' isn't Emacs' image directory,
+ ;; it's probably a user preference, so use it. Then use a
+ ;; relative setting if possible; otherwise, use
+ ;; `image-directory-load-path'.
+ (cond
+ ;; User-modified image-load-path?
+ ((and image-directory-load-path
+ (not (equal image-directory-load-path
+ (file-name-as-directory
+ (expand-file-name "images" data-directory)))))
+ (setq image-directory image-directory-load-path))
+ ;; Try relative setting.
+ ((let (library-name d1ei d2ei)
+ ;; First, find library in the load-path.
+ (setq library-name (locate-library library))
+ (if (not library-name)
+ (error "Cannot find library %s in load-path" library))
+ ;; And then set image-directory relative to that.
+ (setq
+ ;; Go down 2 levels.
+ d2ei (file-name-as-directory
+ (expand-file-name
+ (concat (file-name-directory library-name) "../../etc/images")))
+ ;; Go down 1 level.
+ d1ei (file-name-as-directory
+ (expand-file-name
+ (concat (file-name-directory library-name) "../etc/images"))))
+ (setq image-directory
+ ;; Set it to nil if image is not found.
+ (cond ((file-exists-p (expand-file-name image d2ei)) d2ei)
+ ((file-exists-p (expand-file-name image d1ei)) d1ei)))))
+ ;; Use Emacs' image directory.
+ (image-directory-load-path
+ (setq image-directory image-directory-load-path))
+ (no-error
+ (message "Could not find image %s for library %s" image library))
+ (t
+ (error "Could not find image %s for library %s" image library)))
+
+ ;; Return an augmented `path' or `load-path'.
+ (nconc (list image-directory)
+ (delete image-directory (copy-sequence (or path load-path))))))
+
+
(defun image-jpeg-p (data)
"Value is non-nil if DATA, a string, consists of JFIF image data.
We accept the tag Exif because that is the same format."
"Determine the image type from image data DATA.
Value is a symbol specifying the image type or nil if type cannot
be determined."
- (let ((types image-type-regexps)
+ (let ((types image-type-header-regexps)
type)
- (while (and types (null type))
+ (while types
(let ((regexp (car (car types)))
(image-type (cdr (car types))))
- (when (or (and (symbolp image-type)
- (string-match regexp data))
- (and (consp image-type)
- (funcall (car image-type) data)
- (setq image-type (cdr image-type))))
- (setq type image-type))
- (setq types (cdr types))))
+ (if (or (and (symbolp image-type)
+ (string-match regexp data))
+ (and (consp image-type)
+ (funcall (car image-type) data)
+ (setq image-type (cdr image-type))))
+ (setq type image-type
+ types nil)
+ (setq types (cdr types)))))
+ type))
+
+
+;;;###autoload
+(defun image-type-from-buffer ()
+ "Determine the image type from data in the current buffer.
+Value is a symbol specifying the image type or nil if type cannot
+be determined."
+ (let ((types image-type-header-regexps)
+ type
+ (opoint (point)))
+ (goto-char (point-min))
+ (while types
+ (let ((regexp (car (car types)))
+ (image-type (cdr (car types)))
+ data)
+ (if (or (and (symbolp image-type)
+ (looking-at regexp))
+ (and (consp image-type)
+ (funcall (car image-type)
+ (or data
+ (setq data
+ (buffer-substring
+ (point-min)
+ (min (point-max)
+ (+ (point-min) 256))))))
+ (setq image-type (cdr image-type))))
+ (setq type image-type
+ types nil)
+ (setq types (cdr types)))))
+ (goto-char opoint)
type))
"Determine the type of image file FILE from its first few bytes.
Value is a symbol specifying the image type, or nil if type cannot
be determined."
- (unless (file-name-directory file)
- (setq file (expand-file-name file data-directory)))
- (setq file (expand-file-name file))
- (let ((header (with-temp-buffer
- (set-buffer-multibyte nil)
- (insert-file-contents-literally file nil 0 256)
- (buffer-string))))
- (image-type-from-data header)))
+ (unless (or (file-readable-p file)
+ (file-name-absolute-p file))
+ (setq file (image-search-load-path file)))
+ (and file
+ (file-readable-p file)
+ (with-temp-buffer
+ (set-buffer-multibyte nil)
+ (insert-file-contents-literally file nil 0 256)
+ (image-type-from-buffer))))
;;;###autoload
-(defun image-type-available-p (type)
- "Return non-nil if image type TYPE is available.
-Image types are symbols like `xbm' or `jpeg'."
- (and (fboundp 'init-image-library)
- (init-image-library type image-library-alist)))
+(defun image-type-from-file-name (file)
+ "Determine the type of image file FILE from its name.
+Value is a symbol specifying the image type, or nil if type cannot
+be determined."
+ (let ((types image-type-file-name-regexps)
+ type)
+ (while types
+ (if (string-match (car (car types)) file)
+ (setq type (cdr (car types))
+ types nil)
+ (setq types (cdr types))))
+ type))
+
;;;###autoload
-(defun create-image (file-or-data &optional type data-p &rest props)
- "Create an image.
+(defun image-type (file-or-data &optional type data-p)
+ "Determine and return image type.
FILE-OR-DATA is an image file name or image data.
Optional TYPE is a symbol describing the image type. If TYPE is omitted
or nil, try to determine the image type from its first few bytes
of image data. If that doesn't work, and FILE-OR-DATA is a file name,
use its file extension as image type.
-Optional DATA-P non-nil means FILE-OR-DATA is a string containing image data.
-Optional PROPS are additional image attributes to assign to the image,
-like, e.g. `:mask MASK'.
-Value is the image created, or nil if images of type TYPE are not supported.
-
-Images should not be larger than specified by `max-image-size'."
+Optional DATA-P non-nil means FILE-OR-DATA is a string containing image data."
(when (and (not data-p) (not (stringp file-or-data)))
(error "Invalid image file name `%s'" file-or-data))
(cond ((null data-p)
(error "Cannot determine image type"))
(unless (symbolp type)
(error "Invalid image type `%s'" type))
+ type)
+
+
+;;;###autoload
+(defun image-type-available-p (type)
+ "Return non-nil if image type TYPE is available.
+Image types are symbols like `xbm' or `jpeg'."
+ (and (fboundp 'init-image-library)
+ (init-image-library type image-library-alist)))
+
+
+;;;###autoload
+(defun image-type-auto-detected-p ()
+ "Return t if the current buffer contains an auto-detectable image.
+This function is intended to be used from `magic-fallback-mode-alist'.
+
+The buffer is considered to contain an auto-detectable image if
+its beginning matches an image type in `image-type-header-regexps',
+and that image type is present in `image-type-auto-detectable'."
+ (let* ((type (image-type-from-buffer))
+ (auto (and type (cdr (assq type image-type-auto-detectable)))))
+ (and auto
+ (or (eq auto t) (image-type-available-p type)))))
+
+
+;;;###autoload
+(defun create-image (file-or-data &optional type data-p &rest props)
+ "Create an image.
+FILE-OR-DATA is an image file name or image data.
+Optional TYPE is a symbol describing the image type. If TYPE is omitted
+or nil, try to determine the image type from its first few bytes
+of image data. If that doesn't work, and FILE-OR-DATA is a file name,
+use its file extension as image type.
+Optional DATA-P non-nil means FILE-OR-DATA is a string containing image data.
+Optional PROPS are additional image attributes to assign to the image,
+like, e.g. `:mask MASK'.
+Value is the image created, or nil if images of type TYPE are not supported.
+
+Images should not be larger than specified by `max-image-size'."
+ (setq type (image-type file-or-data type data-p))
(when (image-type-available-p type)
(append (list 'image :type type (if data-p :data :file) file-or-data)
props)))
(delete-overlay overlay)))
(setq overlays (cdr overlays)))))
-(defun image-search-load-path (file path)
- (let (element found pathname)
+(defun image-search-load-path (file &optional path)
+ (unless path
+ (setq path image-load-path))
+ (let (element found filename)
(while (and (not found) (consp path))
(setq element (car path))
(cond
((stringp element)
(setq found
(file-readable-p
- (setq pathname (expand-file-name file element)))))
+ (setq filename (expand-file-name file element)))))
((and (symbolp element) (boundp element))
(setq element (symbol-value element))
(cond
((stringp element)
(setq found
(file-readable-p
- (setq pathname (expand-file-name file element)))))
+ (setq filename (expand-file-name file element)))))
((consp element)
- (if (setq pathname (image-search-load-path file element))
+ (if (setq filename (image-search-load-path file element))
(setq found t))))))
(setq path (cdr path)))
- (if found pathname)))
+ (if found filename)))
;;;###autoload
(defun find-image (specs)
found)
(when (image-type-available-p type)
(cond ((stringp file)
- (if (setq found (image-search-load-path
- file image-load-path))
+ (if (setq found (image-search-load-path file))
(setq image
(cons 'image (plist-put (copy-sequence spec)
:file found)))))
(defimage test-image ((:type xpm :file \"~/test1.xpm\")
(:type xbm :file \"~/test1.xbm\")))"
+ (declare (doc-string 3))
`(defvar ,symbol (find-image ',specs) ,doc))
(provide 'image)
-;;; arch-tag: 8e76a07b-eb48-4f3e-a7a0-1a7ba9f096b3
+;; arch-tag: 8e76a07b-eb48-4f3e-a7a0-1a7ba9f096b3
;;; image.el ends here
HCoop / bpt / emacs.git / blobdiff