With Emacs' doc-view-mode I can easily shrink/zoom/etc PDFs, however, I would like to be able to do the same thing with images. Currently when I open an image I cannot adjust the zoom level to fit it to the frame. I know there is image-mode-fit-frame, however, it does not help when the image is larger than my screen.
Is there a package or mode that will allow me zoom in and out on an image?
Such functionality is provied by packages:
With point in the thumbnail buffer, you can type RET (
image-dired-display-thumbnail-original-image) to display a sized version of it in another window. This sizes the image to fit the window.
It uses ImageMagick's convert command.
You can also use image-dired-external-viewer to avoid the problem and display your images in an external image viewer such as feh.
(add-hook 'image-mode-hook 'eimp-mode)
It uses the mogrify utility from ImageMagick to do the actual transformations.
(kbd "+") 'eimp-increase-image-size
(kbd "-") 'eimp-decrease-image-size
(kbd "<") 'eimp-rotate-image-anticlockwise
(kbd ">") 'eimp-rotate-image-clockwise
(kbd "B +") 'eimp-blur-image
(kbd "B -") 'eimp-sharpen-image
(kbd "B E") 'eimp-emboss-image
(kbd "B G") 'eimp-gaussian-blur-image
(kbd "B R") 'eimp-radial-blur-image
(kbd "C B +") 'eimp-increase-image-brightness
(kbd "C B -") 'eimp-decrease-image-brightness
(kbd "C C +") 'eimp-increase-image-contrast
(kbd "C C -") 'eimp-decrease-image-contrast
(kbd "F ^") 'eimp-flip-image
(kbd "F >") 'eimp-flop-image
(kbd "F <") 'eimp-flop-image
(kbd "N") 'eimp-negate-image
; Commands most relevant to you:
(kbd "S f") 'eimp-fit-image-to-window
(kbd "S h") 'eimp-fit-image-height-to-window
(kbd "S w") 'eimp-fit-image-width-to-window
(kbd "<right>") 'eimp-roll-image-right
(kbd "<left>") 'eimp-roll-image-left
(kbd "<up>") 'eimp-roll-image-up
(kbd "<down>") 'eimp-roll-image-down
(kbd "<down-mouse-1>") 'eimp-mouse-resize-image
(kbd "<S-down-mouse-1>") 'eimp-mouse-resize-image-preserve-aspect
(kbd "C-c C-k") 'eimp-stop-all
eiv - It also uses the ImageMagick package which should provide mogrify.
Complete command list:
eiv-fit-image-to-window - Resize image to current window size.eiv-rotate-current-image - Rotate current image at 90 degrees. eiv-dec-or-inc-image - Resize image to current window size. eiv-diaporama - Start a diaporama on tree. eiv-viewer - The emacs-image-viewer. Allows to navigate in a tree of dir and subdir.I used the source code in lisp/image-mode.el to write this up. Calling this function in any image buffer will resize it to fit to width or height depending on the image and window height/width ratios.
You do need these 2 things for this function to work:
libjpeg loader is used to handle JPEG images. The hack shown in next part of this answer is used to force emacs to use imagemagick loader.
(defun modi/image-transform-fit-to-window()
"Resize the image to fit the width or height based on the image and window ratios.
Imagemagick is required to run this function."
(interactive)
(let* ( (img-size (image-display-size (image-get-display-property) t))
(img-width (car img-size))
(img-height (cdr img-size))
(img-h/w-ratio (/ (float img-height) (float img-width)))
(win-width (- (nth 2 (window-inside-pixel-edges))
(nth 0 (window-inside-pixel-edges))))
(win-height (- (nth 3 (window-inside-pixel-edges))
(nth 1 (window-inside-pixel-edges))))
(win-h/w-ratio (/ (float win-height) (float win-width))))
;; Fit image by width if the h/w ratio of window is > h/w ratio of the image
(if (> win-h/w-ratio img-h/w-ratio)
(image-transform-fit-to-width)
;; Else fit by height
(image-transform-fit-to-height))))
After following through the emacs bug reports #18797, #10746 and #10112, the following solution worked for forcing Imagemagick to load images; put it somewhere in your init.el:
I have forced Emacs to use ImageMagick only for the image files familiar to me: PNG, TIFF, JPEG, SVG; the rest are kept as default. I have chosen to allow gif files to be opened by the default loader as emacs 24.4 has improved support for viewing multi-frame images. The whole regexp is taken from lisp/image.el.
(setq image-type-header-regexps
`(
("\\`/[\t\n\r ]*\\*.*XPM.\\*/" . xpm)
("\\`P[1-6]\\\(?:\
\\(?:\\(?:#[^\r\n]*[\r\n]\\)?[[:space:]]\\)+\
\\(?:\\(?:#[^\r\n]*[\r\n]\\)?[0-9]\\)+\
\\)\\{2\\}" . pbm)
("\\`GIF8[79]a" . gif)
;; ("\\`\x89PNG\r\n\x1a\n" . png) ;; Uncomment this (and comment the below line) to enable inline PNG images in org-mode
("\\`\x89PNG\r\n\x1a\n" . imagemagick) ; PNG
("\\`[\t\n\r ]*#define \\([a-z0-9_]+\\)_width [0-9]+\n\
#define \\1_height [0-9]+\n\\(\
#define \\1_x_hot [0-9]+\n\
#define \\1_y_hot [0-9]+\n\\)?\
static \\(unsigned \\)?char \\1_bits" . xbm)
;; ("\\`\\(?:MM\0\\*\\|II\\*\0\\)" . tiff)
("\\`\\(?:MM\0\\*\\|II\\*\0\\)" . imagemagick) ; TIFF
("\\`[\t\n\r ]*%!PS" . postscript)
;; ("\\`\xff\xd8" . jpeg) ;; Uncomment this (and comment the below line) to enable inline JPEG images in org-mode
("\\`\xff\xd8" . imagemagick) ; JPEG
("\\`\377\330" . imagemagick) ; JPEG
(,(let* ((incomment-re "\\(?:[^-]\\|-[^-]\\)")
(comment-re (concat "\\(?:!--" incomment-re "*-->[ \t\r\n]*<\\)")))
(concat "\\(?:<\\?xml[ \t\r\n]+[^>]*>\\)?[ \t\r\n]*<"
comment-re "*"
"\\(?:!DOCTYPE[ \t\r\n]+[^>]*>[ \t\r\n]*<[ \t\r\n]*" comment-re "*\\)?"
"[Ss][Vv][Gg]"))
;; . svg) ;; Uncomment this (and comment the below line) to enable inline SVG images in org-mode
. imagemagick) ; SVG
))
image-transform-fit-to-widthimage-transform-fit-to-height#18797, #10746, #10112
image-transform-set-scale may be what you are looking for. However it requires Emacs to be compiled with Imagemagick support.
There is also a commented out image-transform-mode in image-mode.el labeled "Not yet implemented."
Here's a solution that lets you scale up and down using the same keys as are used for text scaling, C-x C-= and C-x C--
(defun scale-image ()
"Scale the image by the same factor specified by the text scaling."
(image-transform-set-scale
(expt text-scale-mode-step
text-scale-mode-amount)))
(defun scale-image-register-hook ()
"Register the image scaling hook."
(add-hook 'text-scale-mode-hook 'scale-image))
(add-hook 'image-mode-hook 'scale-image-register-hook)
