It includes the information such as the title of the photo, location, photographer name and comments etc. The owner (or photographer) can add it manually by using any external software such as GIMP or Photoshop. The Descriptive metadata is manually added by the photographer. The technical metadata is mostly generated automatically by the camera devices. Technical metadata contains the camera details, DPI, shutter speed, file size, image format, the date and time when the image is captured or created, the software used to create the image and a few other details. ImageMagick website for an extensive list of options, examples and showcase.There are three types of Metadata, namely Īs the name says, the Technical metadata usually includes technical information of an image.However, an example for false positives are images created with the Diamond-square algorithm. If it exceeds a certain threshold, the data could be considered random and a possible candidate for encryption. In general, testing if a raster image was encrypted can be done by checking the distribution of the pixel components. However, it could be removed or spoofed by an EXIF editing program. Metadata of image formats that have the cipher tag can be used to test for encryption. It is highly advised to read the discussion at Encrypting Images for all sorts of issues, and suggestions, for such commands. $ echo pass_phrase | magick image.png -decipher - image.jpg ![]() $ echo pass_phrase | magick image.jpg -encipher -depth 8 png24: image.png zathura) appear blank, try appending -frame or removing -f from the xdotool command. Note: If screenshots of some programs (e.g. $ import -window "$(xdotool getwindowfocus -f)" /tmp/$(date +%F_%H%M%S_%N).png Import -window "$activeWinId" /tmp/$(date +%F_%H%M%S_%N).pngĪlternatively, the following should work regardless of EWMH support: To avoid overwriting previous screenshots, the current date is used as the filename.ĪctiveWinLine=$(xprop -root | grep "_NET_ACTIVE_WINDOW(WINDOW)") It works with EWMH/NetWM compatible X Window Managers. The following script takes a screenshot of the currently focused window. Import -window root -crop $x$h+$x+$y head_$i.png Xdpyinfo -ext XINERAMA | sed '/^ head #/!d s///' | As long as Xinerama information is available from the X server, the following will work: In this case, you may want to take screenshot of each physical screen individually. If the physical screens are different in height, you will find dead space in the screenshot. Xinerama-based multi-head setups have only one virtual screen. $ convert +append /tmp/0.png /tmp/1.png screenshot.png $ import -window root -display :0.1 -screen /tmp/1.png $ import -window root -display :0.0 -screen /tmp/0.png If you run twinview or dualhead, simply take the screenshot twice and use imagemagick to paste them together: Note: If you prefer graphicsmagick alternative, just prepend "gm", e.g. ![]() With -pause you can specify a delay in which you can, for example, lower some windows. Running import without the -window option allows selecting a window or an arbitrary region interactively. Is harder to use when the correlation between quality and storage size is not clear.Īn easy way to take a screenshot of your current system is using the import(1) command: $ convert image.jpg -quality 85% image_small.jpg Hopefully, this will shorten the transmission time. $ convert image.jpg -define jpeg:extent=3000KB image_small.jpg To achieve reasonable quality for a given storage size: $ magick frame_red.gif -gravity South -chop 0x10 chop_bottom.gif Which is easier as less numbers, or trial and error, is involved. One can also -chop to cut of a single edge from an image, using gravity to select that edge. Where WIDTH and HEIGHT is the cropped output image size, and X and Y is the offset from the input image size. $ mogrify -crop WIDTHx HEIGHT+ X+ Y -format jpg *.png To crop part of multiple images and convert them to another format: $ convert -append input.pngs output.png Crop, chop The basic usage of this facility is to specify the existing, and desired, image formats as the filename extension. Opposite operations can be performed by using a plus instead of a minus. ![]() Note: The sign before an option is important.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |