I implemented application which perform the following:

• reads JPEG image file as input;
• performs decoding JPEG image;
• performs encoding of decoder’s output data to the JPEG format;
• stores encoded JPEG image to the file.

You will need to install libJPEG first.

 sudo apt install libjpeg-dev

Also you need to install Intel TBB library for parallelism.

Donwload this repository and run make file. It generates two console programs: invert and compress.

compress -- console program with minimal interface, which reads JPEG file, decodes JPEG image, compress with given number of quality and stores JPEG image to the file.

invert -- console program with minimal interface, which reads JPEG file, decodes JPEG image, inverts image pixels, compress with given number of quality and stores JPEG image to the file.

• invert [name of original jpeg file] [name of output jpeg file] [quality number - int]
• compress [name of original jpeg file] [name of output jpeg file] [quality number - int]
• NOTE: you need to specify all parameters correct

Examples:

invert cars.jpeg invertCars.jpeg 34

compress cars.jpeg comprCars.jpeg 24

Original image	Inverted image

27.12.2018:

• now class Image uses one single vector instead of vector of vectors for bit map image;
• parallelInvert() method was added in the class Image. It does the same as invert(), only twice (1.5-2.0 times) as fast on average. This result is achieved through the use TBB library functions and template classes. (full description will be added)
• some exceptions are handled (full description will be added later)
• other (full description will be added later)

25.01.2019:

• stdInvert() was added, that uses std::threads for multithreading.

• Write Google Tests
• Handle exceptions
• Update ReadMe

• apodeline.free.fr/DOC/libjpeg - Using the IJG JPEG library
• jpegclub.org/reference - Independent JPEG Group Reference Site
• src/libjpeg.doc - USING THE IJG JPEG LIBRARY
• https://www.threadingbuildingblocks.org/docs/ - Threading Building Blocks (TBB)
• https://software.intel.com/en-us/get-started-with-tbb - Getting Started with Intel® Threading Building Blocks (Intel® TBB)