I Dare You!

by peter_budo

submit your photo


Hall of Fame
View past winners from this year

Please participate in Meta
and help us grow.

Tag Info

New answers tagged

0

This is an issue that confuses many beginners especially. The following are my views on the subject: https://theimageplane.wordpress.com/2015/03/08/raw-and-jpeg-whats-your-preference/


0

The previus answers are verey good. I will just add some "psicological aspects" of the jpg format. If a jpg is well prepared, it looses only about 0.5% information. That is in the vast majority of cases something that the human eye can not see. You need a program to do some analisis and see the diferences (like the analysis Ilmari just did). "Good ...


5

It's not quite lossless, but you can get pretty close using GIMP (or some other editor with a similar feature) and the following two tricks: First, make sure that the border you're adding is a multiple of 8 pixels wide (and preferably a multiple of 16 pixels). This is important because the JPEG compression algorithm breaks the image into 8×8 pixel ...


4

JPEG file size is a meaningless measure, except as an optimization criterion for bandwith/diskspace considerations. Since JPEG is optimized to compress areas with little detail, while preserving fine detail, compression is dependent on the details in the image. There is no way you could produce a 20mb file from eg. a plain white image, no matter the ...


3

Sorry if this is not exactly what you wanted but... It sounds like your adding a white border as an aid for positioning your image when printing. Why not focus on learning the printing interfaces properly and avoid dodgy hacks like this? The other issue this brings up is are you allowing the printing program to resize your 4680x3120 image to fit the correct ...


35

Although Philip's answer is the best way to go, it is possible to do what you want entirely within the sphere of JPEG. JPEG works by breaking your image up into blocks called Minimum Coding Units (MCUs), typically 16×16 each, and compressing them separately. You can see this in images when you crank the compression level up very high. At more ...


19

The point to remember here is that you lose quality when saving the photo into a lossy compression format. So long as you save the photo in a lossless format (PSD, TIFF, etc) after adding the border, you won't lose any more data than you've already lost by saving the photo as a JPEG in the first place.


1

It is possible in theory, but no software I know is designed to do it. First, you can't do it in the way your lossless crop/rotate works. Lossless JPEG manipulation is possible, because only one stage of the whole JPEG compression process is lossy. As long as the pixel values in 8x8 (or 16x16) blocks are not changed, the blocks themselves can be rearranged, ...


1

No. The reason you can't is because all of the color information in a JPEG is already displayed when you first view it. You can remove some of that information, you can even amplify what is left, but you can't add any information that isn't already there. This is in contrast to a RAW file. When you view a RAW file you are only viewing part of the ...


1

There are several reasons to shoot RAW and JPEG: Just to recap: RAW is the information the camera gathers from the sensor, without (or just a bit) modification. JPEG is a lossy compressed image, which is created out of the RAW file according to your settings of film simulation, dynamic range optimisation, noise reduction and so on. In short, it misses ...


2

As I don't have any extra photo editing programs I used iPhoto to do this. Open iPhoto with the option key held down. This gives you the option to create a new library. Create a temporary one somewhere where it will be easy to find and delete it later. Import all the Raw Pictures into the new library. Export them all in the required format. Quit and delete ...



Top 50 recent answers are included