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Questions tagged [jpeg]

JPEG is a lossy-compression method for a digital image. The images can end up in many JPEG image containers (JPEG, JPG, JIF, JPE, JFI, JFIF) depending on the parameters surrounding the compression of the image data. JPEG is actually an acronym for Joint Photographic Experts Group, the group that created the compression standard for JPEG.

362 questions
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Can we change size of an JPEG image with out decoding and re-encoding it?

I want to convert a 640x480 JPEG image to 320x240. I know it can be done by decoding the JPEG image into raw YCbCr, scale it and re-encode it into JPEG. But is it possible possible with JPEG encoding to directly scale the image with out decoding?
Necktwi
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2
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1 answer

What is "AppleMark"?

I have 2 JPEG files that appear the same, i.e. the same pixel data, same dimensions, but one of them is a much larger file size. The download time for these files is important to my client, so I need to determine where the larger one came from and…
Liam
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2
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How to open mystery JPEG file?

I have a folder that contains JPEG files that I cannot open. Here is one example mystery file. Can anyone help me to open the file or suggest a way of recovering the data if it is corrupted? [update] I found the files on an old external hard drive.…
Liam
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Unable to open invalid jpg file

A few days ago I took pictures from my camera and uploaded them to my computer. Now the photos that I took few days ago was appear to be corrupted or invalid format. I have tried use third party software and repair tools but have been unable to…
user1579414
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damaged jpg: how do I recover it?

I found on my disk some damaged jpg, they look like this: Any idea about how to recover them? Here is damaged image file:
Paolo Benvenuto
  • 399
0
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3 answers

Seemingly identical JPG files, though one is corrupt

I posted this question the other day: Suggestions on how to repair corrupt files The files I used in example were perhaps not the best. These are still ever so slightly NSFW, but I now have two files that I feel are better for figuring out how to…
user17245
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0
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1 answer

Suggestions on how to repair corrupt files

( Warning, sample images are slightly NSFW; tattoo work shows a little bit of boob. ) Previously I had a Mac OS X sparse-bundle dmg and used DropBox on two computers. I would add to my secure sparse-bundle which was in my DropBox folder. Then one…
user17245
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5 answers

How i can apply water mark on many images in a single click

I have a large collection of Books. I have all pages in JPEG format. I want to apply a text of My website transparent on each page. I have made an image by the help of Adobe photo shop. But its very difficult for me to apply on each page as it will…
tom
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2 answers

When is The GIMP gonna let me save ( not export ) .jpg, .png, etc.?

When is The GIMP gonna let me save ( not export ) .jpg, .png, etc.? Not Why Not, Just tell me when. Having to export the most common graphic file extensions in the world is Jejune.
reidh
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