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123

In the poppler-utils packages there is the utility pdftoppm capable of converting pages from a pdf file to ppm, png or jpeg format: pdftoppm -png file.pdf prefix will produce prefix-01.png etc. for each page. By default the resolution is 150dpi. Increase the resolution (for higher quality output) as follows: pdftoppm -rx 300 -ry 300 -png file.pdf prefix ...


88

Install imagemagick Using a terminal where the pdf is located: convert -density 150 input.pdf -quality 90 output.png whereby: PNG, JPG or (virtually) any other image format can be chosen -density xxx will set the dpi to xxx (common are 150 and 300) -quality xxx will set the compression to xxx for PNG, JPG and MIFF file formates (100 means no compression)...


77

Get the partition layout of the image $ sudo fdisk -lu sda.img ... Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes ... Device Boot Start End Blocks Id System sda.img1 * 56 6400000 3199972+ c W95 FAT32 (LBA) Calculate the offset from the start of the image to the ...


63

Same command, with an extra option: convert myfigure.png -resize 200x100 myfigure.jpg or convert -resize 50% myfigure.png myfigure.jpg


62

Gthumb is a nice image viewing/editing tool with simple editing tools like cropping. Instructions for cropping in gThumb 3.2.8 Open your image in gThumb Open the Edit sidebar by pressing e or clicking on the easel in the top-right corner of the window In the sidebar click on Crop and then crop the image as you desire Once finished press ...


57

If you're willing to use a terminal, you can do: convert image1.jpg image2.png text.txt PDFfile.pdf outputFileName.pdf It worked for me, but the problem is it converts the text.txt file into an image, so you can't highlight the text in the resulting pdf. (this is @Alaa's comment converted to a Community Wiki answer)


46

Update for Ubuntu 16.04: With the new losetup this is now easier: sudo losetup -Pf disk_image.raw See the rest of the answer for older versions of Ubuntu. An easy solution is using kpartx: it will figure out the partition layout and map each to a block devices. After that all you have to do is mount the one you want. Open Terminal, locate the disk ...


42

digiKam Add all the photos to your collection. In the menu, select “Tools / Find duplicates”. This will look for duplicates across your whole collection. findimagedupes A command line tool. Pass all the images you want to compare on the command line. Geeqie (formerly GQview) In the menu, select “File / Find duplicate”. Drag and drop image files do ...


33

Easy. Install imagemagick $ sudo apt-get install imagemagick It's simplest usage is: $ convert File.tif File.jpg It is smart and goes by your file extension. Now, for doing batch conversions, we shall use a loop. cd into the directory where your tif files are. then: $ for f in *.tif; do echo "Converting $f"; convert "$f" "$(basename "$f" .tif).jpg"...


28

Press PRINTSCREEN for a screenshot of the whole Desktop. Press ALT + PRINTSCREEN for a screenshot of the current active Window. Press SHIFT + PRINTSCREEN for a screenshot of a Region you select with your Mouse.


27

Nautilus's thumbnailing routines actually come from the libgnome-desktop library, so it is possible to run the same thumbnailers outside of the file manager. The API is a little complex, but the following Python script should help: #!/usr/bin/python import os import sys from gi.repository import Gio, GnomeDesktop def make_thumbnail(factory, filename): ...


27

ImageMagick Trim The command line option trim used together with convert, or mogrify lets you trim borders of the identical color as the corners of an image. Usage: convert input.png -trim output.png The additional options -fuzz also removes colors near the corner colors. Use option +repage to remove a canvas (if applicable). ImageMagick Batch Trim (...


26

Once the image is opened you can right click on it and choose to open with Shotwell Image Viewer. It will open up a new window where you can crop/edit the image and save it. Once saved you can close the 2nd window and see the changes in the default image viewer. Alternatively you can set Shotwell Image Viewer to be your default image viewer.


22

FSlint fslint is a graphical program that can find duplicate files of any type by md5sum. If the images are not identical, they won't be flagged as duplicates. The image below shows a bunch of duplicate pdf files in my Downloads directory: You can change the advanced search parameters to search by file type and restrict yourself to images only. That's ...


20

You can use PosteRazor. Start the Software Center. Search for PosteRazor Install it. PosteRazor allows to import an image and then takes you through a wizard that allows to cut it in pieces, depending on the type of paper you will be printing on.


20

Use the command identify, which is part of ImageMagick. Examples: $ identify ZEAKR.jpg ZEAKR.jpg JPEG 400x600 400x600+0+0 8-bit DirectClass 49.9KB 0.000u 0:00.000 or $ identify -verbose ZEAKR.jpg Image: ZEAKR.jpg Format: JPEG (Joint Photographic Experts Group JFIF format) Class: DirectClass Geometry: 400x600+0+0 Resolution: 72x72 Print size: ...


20

Using the tools provided with ImageMagick We can easily join, i.e. "montage" images into one large image with the following command montage -geometry 500 image1 image2 [...] output See the project page for many parameters of the geometry option. In the example above all images will be scaled to a width of 500 pixels before they are joined. Adapt this ...


19

It sounds like you're trying to make a video. If that's the case, then I'd use a proper video format. In this case, I'd use ffmpeg to convert the individual PNG files to a H.264 video. Since ffmpeg is made to work with videos that can be hours long, it should have no problem with your thousands of images. Using H.264 instead of animated gif will result in ...


18

If you want CLI only: sudo apt-get install imagemagick mogrify -resize 320x240 Image.png mogrify -resize 50% Image.png mogrify -resize 320x240 *.jpg If you wanna try GUI: Install nautilus-image-converter sudo apt-get install nautilus-image-converter It adds two context menu items in nautlius so you can right click and choose "Resize Image".(The ...


18

Install pdftk sudo apt-get install pdftk Pdftk If PDF is electronic paper, then pdftk is an electronic staple-remover, hole-punch, binder, secret-decoder-ring, and X-Ray-glasses. Pdftk is a simple tool for doing everyday things with PDF documents. You can create pdf files from text or images with Libre Office then to stitch these togeter with other pdf ...


18

See the montage command from imagemagick (sudo apt-get install imagemagick). montage -geometry 250x250+0+0 image1.png image2.png out.png This will resize each image (to 250px with no deformation) and combine them with no margin. More montage examples. You can also use convert (example with wildcards): convert -append pixpixp-*.jpg newpix.jpg


17

Method 1: Goto Applications>>Accessories>>Take Screenshot Now you can select the portion of a screen. Method 2: If you use shutter Applications>>Accessories>>Shutter Open it and click selection in the top of the screen. Now you can select the portion of the screen. Method 3: Take a screenshot of a whole desktop by ...


17

On the command line, the tool to manipulate bitmap images is imagemagick or graphicsmagick (GM is a split of the IM project, and more actively developed). This is a good option if you often use the same parameters. convert raw.jgp -crop 800x460+100+20 cropped.jpg # ImageMagick gm convert raw.jgp -crop 800x460+100+20 cropped.jpg # GraphicsMagick For ...


17

Changing the date and time are easy in Shotwell. Select the photos you want to adjust and go to the menu like this: Select Photos/Adjust date and time. That brings up a menu like this: If all the photos are off by the same amount, you can do them all in one go. If you used more than one camera and they were off by different amounts, you have to ...


16

The act of extracting text from images is called OCR and Ubuntu has a wiki page dedicated to OCR. From that page: Available OCR tools The Ubuntu Universe repositories contain the following OCR tools: gocr - A command line OCR fuzzyocr - spamassassin plugin to check image attachments libhocr0 - Hebrew OCR ocrad - Optical Character Recognition program ...


16

GPicView I'll recommend to you this Simple and Fast image viewer. As you say that you computer is not a super fast calculator you should look for software with a few functions (the fewest possible), and this software meets this requirement, see the next screen-shoot and you will notice it. You can install it through the Software-Center.


15

The good replacement is gthumb . You can easily install it through Ubuntu Software Center. It has all functions that you require.


15

Edit : works with util-linux >=2.21. At the time of writing ubuntu ships with version 2.20 only From man losetup : -P, --partscan force kernel to scan partition table on newly created loop device So just run $ sudo losetup -f --show -P /path/to/image.img to create device nodes for every partition of your disk image on the first ...


15

You may try also this plugin, Export Layers. I've tested it with png format and it worked. You just select the folder and the format and you get all the layers there, each one in its own file.



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