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Questions tagged [libjpeg]

libjpeg is a widely-used free software library written in C which implements JPEG decoding and encoding functions alongside various utilities for handling JPEG images. This library is maintained by the Independent JPEG Group (IJG), an informal organization which is not affiliated with the JPEG ISO committee.

Official website

libjpeg is a widely-used free software library written in C which implements JPEG decoding and encoding functions alongside various utilities for handling JPEG images. This library is maintained by the Independent JPEG Group (IJG), an informal organization which is not affiliated with the JPEG ISO committee.

The following utility programs are available with libjpeg:

  • cjpeg and djpeg, for performing conversions between JPEG and some other popular image file formats.
  • rdjpgcom and wrjpgcom, for inserting and extracting textual comments in JFIF files.
  • jpegtran – a utility for lossless transcoding between different JPEG formats.
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How to fix homebrew permissions?

I have uninstalled and installed Homebrew 3 times now because it seems to never allow me to install anything as it denies me permissions at the end of most installations. As an example I will post this libjpeg download scenario that I'm currently…
Paul Rada
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PIL /JPEG Library: "decoder jpeg not available"

I tried to use PIL to do some JPEG work in my django app with PIL but I'm getting this IOError.. not sure what to do. ""decoder jpeg not available"" Am I missing the JPEG decoder from my server? If so, how do I fix it?
Brian D
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Installing PIL with JPEG support on Mac OS X

I posted a question before regarding this subject, and read other ones posted before, but none has successfully solved my problem. I am trying to install PIL on Mac OS X Lion, as I need it for a Django application. I also need JPEG support, so I…
user1034697
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Compiling libjpeg

Is there anyone who succeed to include libjpeg in some compiler? I tried everything: Dev C++, VS10, CodeBlocks, copy the headers and the lib by hand, add with the linker but nothing. Right now I am really confisued as there is not an official guide…
NiVeR
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Write to memory buffer instead of file with libjpeg?

I have found this function which uses libjpeg to write to a file: int write_jpeg_file( char *filename ) { struct jpeg_compress_struct cinfo; struct jpeg_error_mgr jerr; /* this is a pointer to one row of image data */ JSAMPROW…
Richard Knop
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Compiling PHP with GD and libjpeg support

I compile my own PHP, partly to learn more about how PHP is put together, and partly because I'm always finding I need modules that aren't available by default, and this way I have control over that. My problem is that I can't get JPEG support in…
Robin Winslow
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Error handling in libjpeg

I am using the C++ JPEG library (libjpeg) and I have realized that when some functions fail exit() is called and the application is closed. How can I override this behavior and prevent the application from closing on libjpeg errors?
Didac Perez Parera
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How to install libjpeg on OSX?

libjpeg or libjpeg-turbo are requirements for installing Pillow, which is a new requirement for storing images on django. So I need to install Pillow but that won't work until I get jpeg support which comes by way of packages called libjpeg or…
jeffery_the_wind
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How to install libjpeg?

I tried these commands: pip install libjpeg8-dev pip install libjpeg-dev pip install libjpeg-devel pip install libjpeg pip install libjpeg62 libjpeg62-dev but none of them works. What is the right command with pip?
DSblizzard
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libjpeg API and Reference

I am having trouble finding an API that details functions calls and return values... The headers aren't exactly very clean either... I have found tons of examples, but I'm interested in error handling (return values). Am I approaching this wrong…
Constantin
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Throwing an exception in C++ in a C callback, possibly crossing over dynamic library boundary... is it safe?

I'm using libjpeg right now to save JPEG images. If there is an error, libjpeg's default behavior is to call exit(), which I want to avoid since it's not a fatal error for my program. libjpeg allows you to use your own error manager, and mandates…
Cornstalks
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Python, PIL and JPEG on Heroku

I have a Django site, hosted on Heroku. One of the models has an image field, that takes uploaded images, resizes them, and pushes them to Amazon S3 so that they can be stored persistently. This is working well, using PIL def save(self, *args,…
errkk
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Do the libjpeg and the .Net jpeg codec really differ significantly on monochrome data?

I work with a lot of monochrome image data and this morning I noticed that there appears to be a significant difference between the way libjpeg and the .Net jpeg codec handle monochrome data. It appears that a monochrome image saved at ANY quality…
user334911
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PHP Imagick JPEG Optimization

I'm using PHP Imagick to resize images at runtime. The site has an image upload feature and we can't trust the user to use web-friendly JPEGs, as during the mass-import there are many 3 to 5MB images, and even a few as large as 13MB. Each image…
MaKR
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Can I use libjpeg to read JPEGs with an alpha channel?

There seems to be some debate about whether JPEGs with alpha channels are valid or not. The answer I had always understood to be correct is that in the JPEG FAQ, which is essentially "No". (This is reiterated in another question on Stack…
Mark Longair
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