29

I used ImageMagick on Ubuntu to resize those big pictures. convert -resize 10% source.jpg dest.jpg It took awhile, but worked with 1 GByte of RAM, the tool created a 4.7 Gbyte swap-like file for itself. More information is on AskUbuntu.


13

I have found the free waifu2x very good for upsizing images. You can try an online demo. It uses "Deep Convolutional Neural Networks" to predict what the missing image data should be. It works better for line art, but is definitely acceptable for photos.


12

Photoshop's Batch command can do this. You would essentially 'record' yourself performing the crop etc once, then run the recording on all the files you want. If you want to automatically resize the smaller images you would have to do a little scripting. Irfanview also has a comprehensive image batch processor but might require a bit of experimentation to ...


12

You have to convert them to some other format, but that format doesn't have to be JPEG. For example, you could save the files as TIFF or PNG instead of JPEG. RAW files are data read more or less straight from the sensor, so it doesn't make sense to "resize" such files. You have to instead process them into a useable image format, which you can then ...


11

First of all you need to use a good resize algorithm for that case. Lanczos, or Photoshop's Bicucbic optimized for reduction. And then to make for better contrast around the letters you can use some output sharpening. Secondly, there is a minimum resolution you can use to render the fine letters. The book is a perfect example because of the different fonts ...


11

Any photo you're never going to use again is taking up "unnecessary" space, and frankly no matter what happens to image processing technologies in the future, you're probably not going to go back and reprocess some low quality photos from 10 years ago. On the other hand, disk space is cheap (unless you're Google, Amazon, etc). Very roughly, my SLR has a ...


10

ImageMagick let's you run commands in a windows command window. You need to be comfortable with creating Dos batch files. For an example see the last post in this discussion: http://www.imagemagick.org/discourse-server/viewtopic.php?f=1&t=21112 Relevant example from this forum post: @echo off cd C:\Users\user\Desktop\New\New folder convert *.jpg -...


10

Have a DOG sniff out blur in the photos. If you're going to be penalizing for digitally enlarged photos, you might as well penalize for out-of-focus photos too. The blurred edges and details in both cause the same bad experience for viewers, regardless of whether it is caused by a small original or poor focus. What you want to do is detect blur, which is an ...


9

Theoretically, most image formats could be downscaled progressively, without loading the entire image into memory, however I do not know any tools that really implement such feature, except for JPEG: it is special in that you can not only downscale without loading full resolution, but also downscale without decoding full resolution, thanks to the creative ...


8

You could use dcraw to convert the raw image data to a "raw" tiff file that only contains the raw image data. You do that by giving the command "dcraw -D filename". This will produce a tiff file without any demosaicing or scaling. Such a tiff file is then smaller than an ordinary tiff file because each pixel is then only either a "red", "green" or a "blue" ...


7

First I thought you wanted batch resize, which many programs can do. But then I realized you want to do a combination of resizing and cropping, and you want the computer to calculate how to best cut out 600x600 pixels from the image dynamically. It is because it is not a "one true solution" kind of task, as it is usually human judgement call, how to crop ...


7

You can also try using Picture Resizer on Windows (I love this tool) You simply drag and drop the picture on this simple EXE It is especially useful if you have many pictures to convert as you can do many at a time. All the config is done through the naming of the EXE which is brilliant IMO I have never tried it with huge file though.


7

Use a copy of your file, do not resize your original photo. You can use this free program: http://www.gimp.org/ Using Gimp: Open your file. Use the rectangle select tool. (Define some initial dimensions to set the proportion you need) Move it, scale if from the corners to mantain the proportion and frame your image. Menu > Image > Crop to selection. ...


7

The "ImageOptim" tool pulls together a bunch of other things, and in the case of JPEG files, the relevant thing is the MozJPEG optimizing encoder. If you use this encoder and then resize and save with a different encoder, you will lose the benefit. Saving with the optimizer needs to be the last step. Also worth noting: if you're starting with a JPEG and ...


6

Every digital image has a specific size: the width and height in pixels. The amount of information depends on that. In digital image files, the number of pixels per inch is just a hint. It indicates a proportion that should be used for calculating the actual size of the image when printed. If you have an image of 1000x1000 pixels and you print it at 100ppi,...


6

It depends. If you have sufficient pixels for the size you need, than all you need is to change the DPI. So lets say you have a 12 megapixel image (4000 x 3000 pixels) at 300 DPI, then changing the DPI to 100 will make it 3 times bigger. This will take the 10" tall image and make it 30". Should you judge that you do not have enough pixels, you need to ...


6

Select the RAW photos, then do an Export. In the Export Location section, choose Export To: Same folder as original photo. Check the Add to This Catalog Checkbox. Select the file output options you want for the new images. Export the images. At this point the JPG's will be imported into the same folder, and your RAW files should still be selected, ...


5

If you like programing, you can use Python (computer language) and an excellent library know has PIL to crop, re-size, plot histograms, get individual pixel vales, etc... on a programmatic level. Thus you can easily write a simple script to find all images in a folder and perform the operation. This code should do exactly what you want and should process a ...


5

Pixels per inch don't actually exist until the image is rendered onto some physical medium such as paper or the monitor on your computer. The device doing the rendering determines PPI and PPI determines how large the image will appear when rendered. Rendering your 4000x3000 on a device capable of producing 240 PPI would produce a 16.6"x12.5" physical image....


5

To understand why you can't do this, it's helpful to understand how RAW works. A RAW doesn't actually contain colored pixels, it's a single channel ("gray scale") image representing alternating red blue and green pixels called a Bayer pattern. To actually get the "actual" pixels, you have to extrapolate from each of the pixels neighbors using a complex ...


5

Depends. If you just resized the image in Word, it probably only changed the display scaling and didn't actually resize the image. If you did actually resize the image, though, this is an operation which inherently discards data. Once that information is gone, there's no way to get it back, because there's no where to get it back from.


4

ThumbsPlus can do what you request. On the Image menu, select Batch Process or press F12 and answer the interactive prompts. You can add multiple operations to a set and save it for immediate use as well as future use. In the future, just access the set name you previously configured to automatically run it on a directory or selection of photos, or even an ...


4

Sizzlepig.com is an online tool that will do this easily, you can set the "blueprint" size to be 600x600, and then have it crop center all the images. For the part "For images that are smaller than 600x600 I'd like the program to increase the size of the image to that dimension." I'd highly recommend NOT attempting to upscale the images, but trying to find ...


4

You can actually use Lightroom to do this - indirectly. But first with 1 Tb drives under $100 even already in cases would it not be better to just add storage? But since you said that was not an option here is what you can do with Lightroom. Select the images you want in the Library view and use the Export... button to output .jpg files of the size you ...


4

Although it's very clear in the sharp lines of letters, this actually happens to all detail when a digital image is resized. The algorithms used to shrink an image interpolate information from the surrounding pixels. This prevents artifacts like jaggy lines (aliasing, in computer graphics terminology), but introduces blur. The easiest approach is to run a ...


4

There are many different free and paid software to do this and most of them have different algorithms to do so with various qualities. As the process have to "guess" what happens between each the true pixels (that exist in the original) the chosen "interpolation filter" will make its own "assumptions" how to deduce from the neighborhood what happens. Each ...


4

Do the math. If you really need 300 DPI, then at most your picture can be (2500 pixels)/(300 pixels/inch) = 8.3 inches wide. If you want bigger than that you either can't, or you have to relax your resolution requirements. 200 DPI might still be good enough for something hand-held, for example. The resolution the picture needs to have depends on viewing ...


3

If you have a circle made by putting a black spot in the center spot on each side of a 3 by 3 grid, what do you get if you take a photo of it that uses 300 spots? You get a square on the center of each side using a bunch of pixels to make each square. You can't increase the amount of information in an image if there is no information to capture. Your ...


3

You can take a photo that's arbitrarily detailed with respect to the dots that exist in your subject (at 300dpi), but you can't find new dots where there are none in the print now. Perfect resize (and other resizing algorithms) will attempt to deduce what the "dots between the dots" should look like base on interpolation algorithms. Like most photo ...


3

The reasons for doing sharpening as the final step are primarily because the intended output media determines what sort of sharpening is applied, the idea is that you are compensating for any softening that will occur during printing, or resizing for the web. However, sharpening is more or less a cumulative effect. This means that if you sharpen the eyes as ...


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