Re: Screenshots, frame shots straight from Emacs

[Hongyi Zhao]

On Fri, Jul 23, 2021 at 4:56 PM Hongyi Zhao <hongyi.zhao@gmail.com> wrote:
>
> On Fri, Jul 23, 2021 at 1:55 PM Jean Louis <bugs@gnu.support> wrote:
> >
> > * Hongyi Zhao <hongyi.zhao@gmail.com> [2021-07-23 03:53]:
> > > 1. Have the delay feature, so that I can do some operations before the
> > > screenshot is captured, say, click on mouse button, open a dropdown
> > > menu, and so on.
> >
> > This improved function will allow that you invoke for example:
> >
> > C-5 M-x frameshot to delay for 5 seconds.
>
> Good idea.
>
> > But this Emacs function I think will not allow to get the screenshot of the 
> > dropdown, maybe it
> > requires using threads, now I don't know how to do it within Emacs.
>
> Anyway, thank you very much for your help.
>
> > (defun frameshot (&optional prefix)
> >   "Save Emacs frame as frame shot.
> >
> > Directory is determined by variable `frameshot-directory' and if
> > not defined, it will be saved in the `$HOME' directory."
> >   (interactive "p")
> >   (let ((delay (or prefix 0)))
> >     (run-with-timer
> >      delay nil
> >      (lambda ()
> >        (let* ((image (x-export-frames nil (or frameshot-format 'png)))
> >               (base-directory (or frameshot-directory (getenv "HOME")))
> >               (directory (concat (file-name-as-directory base-directory) 
> > (format-time-string "%Y/%m/%Y-%m-%d/")))
> >               (file (concat directory (format-time-string 
> > "Screenshot-%Y-%m-%d-%T.") (symbol-name frameshot-format))))
> >          (make-directory directory t)
> >          (with-temp-file file
> >            (insert image))
> >          (find-file directory)
> >          (message "Frame shot saved as `%s'" file))))))
> >
> > To capture all screen I am using this external Common Lisp script,
> > that invokes maim:
> >
> > #!/usr/bin/clisp
> >
> > (load 
> > "/home/data1/protected/Programming/git/RCDBusiness/lib/lisp/date-time.lisp")
> >
> > (defparameter *image-capture-program* "maim")
> > (defparameter *image-type* ".png")
> > (defparameter *image-directory* 
> > "/home/data1/protected/Media/Pictures/Screenshots")
> >
> > (let* ((filename (concatenate 'string (timestamp-filename) *image-type*))
> >        (year (substring filename 0 4))
> >        (month (substring filename 5 7))
> >        (date (substring filename 0 10))
> >        (directory (concatenate 'string *image-directory* "/" year "/" month 
> > "/" date "/"))
> >        (command (concatenate 'string *image-capture-program* " \"" 
> > directory filename "\""))
> >        (rox-command (concatenate 'string "rox " directory)))
> >   (print directory)
> >   (print command)
> >   (ensure-directories-exist directory)
> >   (shell command)
> >   (shell rox-command))
> >
> > You could install either `maim' or other system screenshot program and
> > use that one.
>
> Thank you for recommending `maim' to me. From its official description
> [1], it can be seen as an improved scrot, which is the one used by me
> now.
>
> [1] https://github.com/naelstrof/maim

Further comment, based on my tries and the discussions here [1], the
imagemagick and shutter [2] are more powerful and versatile than maim
and scrot.

[1] https://askubuntu.com/questions/584778/how-to-capture-a-drop-down-menu
[2] https://github.com/shutter-project/shutter


> > > 2. Have the post-processing feature, which can be used for some
> > > touch I am not sure whether the recommended method here has these
> > > characteristics.
> >
> > I am often using few simple functions for processing that invoke
> > ImageMagick:
> >
> > (defvar *image-default-resize-size* 1536)
> > (defvar *image-resize-sizes* '())
> >
> > ;; This function optimizes image for websites to reach the optimum
> > ;; Internet speed
> >
> > (defun optimize-image-jpg (file &optional quality)
> >   "Optimizes the JPG image with quality 70%"
> >   (if (rcd-which-list '("mogrify"))
> >       (let ((extension (file-name-extension file))
> >             (quality (or quality "70")))
> >         (when (string-match "\\(?:\\(?:jpe?\\|pn\\)g\\)" (downcase 
> > extension))
> >             (message "Optimizing `%s'" file)
> >             (call-process "mogrify" nil  "-sampling-factor" "4:2:0" 
> > "-strip" "-interlace" "JPEG" "-colorspace" "RGB" "-format" "jpg" "-quality" 
> > quality file)
> >             (message "Optimizing FINISHED for `%s'" file)))
> >     (rcd-warning-message "RCD ERROR: `mogrify' not found in $PATH")))
> >
> > ;; Mark files in Dired, optimize images
> >
> > (defun optimize-jpg-images-dired ()
> >   "Optimizes JPG images inside of Dired"
> >   (interactive)
> >   (let ((files (dired-get-marked-files)))
> >     (while files
> >       (optimize-image-jpg (pop files)))
> >     (revert-buffer)))
> >
> > (defun image-resize (file &optional size)
> >   "Resizes the JPG image with default size"
> >   (if (rcd-which-list '("mogrify"))
> >       (let ((extension (file-name-extension file)))
> >         (when (or (equal (downcase extension) "jpg")
> >                   (equal (downcase extension) "png"))
> >           (let* ((file (shell-double-quote file))
> >                  (command (format "mogrify -resize %s \"%s\"" size file)))
> >             (message command)
> >             (call-process-shell-command command))))
> >     (rcd-warning-message "RCD ERROR: `mogrify' not found in `$PATH'")))
> >
> > ;; Mark files in dired, resize images
> >
> > (defun image-resize-dired ()
> >   "Resizes images"
> >   (interactive)
> >   (let ((files (dired-get-marked-files))
> >         (size (read-number "Size: " *image-default-resize-size* 
> > '*image-resize-sizes*)))
> >     (while files
> >       (image-resize (pop files) size))
> >     (revert-buffer)))
> >
> > If you know what exactly you wish to do to images then it is possible
> > to use same methods and invoke ImageMagick processing.
>
> Other possible processing includes highlighting some regions with
> square or circle,  adding some text comments, and drawing some lines
> or arrows, and so on. I'm not sure whether all these trivial
> operations can be done by the method similar to the above.
>
> Regards,
> Hongyi



-- 
Assoc. Prof. Hongyi Zhao <hongyi.zhao@gmail.com>
Theory and Simulation of Materials
Hebei Vocational University of Technology and Engineering
No. 473, Quannan West Street, Xindu District, Xingtai, Hebei province