CompJPEG - JPEG Image Compresser

A commandline program that uses discreet cosine transfrom (DCT) to implement lossy compression of JPEG images. This program only compresses JPEG images with RGB color channels. A command interpreter is created to manage objects for the CompJEG program

Goals of the Project:

• Decompose each phase of JPEG image compression into simple programs with scarce use of libraries
• Create a simple command line tool that can compress images and store details of the compressed files
• Satisfy ALX Africa requirement as a software engineering student

Functionalities of the command line interpreter

• compress image(s) from stdin, json files, text files and directory
• show the details of the compressed image
• display the compressed image
• delete the compressed image

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Table of Content

• Environment
• Getting Started
• Command Description
• Examples
• Authors
• License

Environment

This project was interpreted and tested on Ubuntu 20.04 using python3 (version 3.10)

Getting Started

1. Clone the project repository

	git clone https://github.com/binael/CompJPEG.git

2. Access the repository

	cd CompJPEG

3. This stage is where a python virtual environment for the project is created. Note that a virtual environment has already been created and if you want to use it, you can skip this step

	python3 -m venv .venv

4. Activate the python virtual environment. The below step will work if you use the already created virtual environment or created one with (step 3)

	source project_env.sh

If above did not create a virtual environment, run the below:

	source .venv/bin/activate

5. Install the requirements for the program

	./build.sh

6. Run setup to ensure all imports are functional

	pip install -e .

The environment is all set up

7. You can start run the program in either interactive or non-interactive mode
   • Interactive mode: ./main.py
   • Non-interactive mode: echo "<command>" | ./main.py

Command Description

Note that all inputs and options to any command must be a key value pair, else the command returns an error. Check usage of each command for more information

1. show id=<image id> mode=<option>

Opens a window to display the image file requested by the user

• Parameters for show command:
  • id [default=<last compressed image id>] : <image id>
  • mode [default='compressed'] : 'compressed' or 'compare' or 'original'
• Usages for show command:
  • show id=<image id> mode=<option> Displays the image having mode of the chosen image id
  • show mode=<option> Displays the mode of the last compressed image
  • show id=<image id> Displays only the compressed image with the given id
  • show Displays only the last compressed image

2. delete id=<id> remove=<option>

Deletes the stored object detail for each image with option to delete the compressed image

• Parameters for delete command:
  • id [default=<'last compressed image id'>]: <image id> or 'all'
  • remove [default=True]: True or False
• Usages for delete command:
  • delete id=<id> remove=<option> Removes the given id or all id objects in database, and the compressed image files if remove is true
  • delete id=<id> Removes the given id or all id objects in database with their compressed image files
  • delete Removes the last compressed image object and its image file
  • delete remove=<option> Removes the last compressed image object and the compressed image file if option is True

3. detail id=<id>

Shows the details (like size, resolution, id, compression time etc) of the compressed image file(s)

• Parameters for detail command:
  • id [default=<'last compressed image id'>]: <image id> or 'all'
• Usages for detail command:
  • detail id=<image id> Shows the detail of the object with the given image id
  • detail id=all Shows the details of all compressed objects in the database
  • detail Shows the detail of the last compressed file object

4. compress "path=<image path1> quality=<int>" "path=<"image path2> quality=<int> ...

Takes up input details from standard input (stdin) and compresses the image file(s) with the desired quality

• Parameters for compress command:
  • path : <image path name>
  • quality : <int>
• Usages for compress command:
  • compress "path=<image path1> quality=<int>" "path=<"image path2> quality=<int> ... Note that each detail of files to compress must be in quote to separate from the next detail

5. compressFiles type=<option> path=<file path>

Takes input details from files or directories and compresses the image file(s) with the quality. Note that directory paths have default quality of 50

• Parameters for compressFiles command:
  • type : 'json' or 'text' or 'directory'
  • path : <image path>
• Usages for compressFiles command:
  • compressFiles type=<option> path=<file path> Compresses all the image files found in the given directory or the file
• Example for accepted format for json and text file details:
  • Text File Example
  • Json File Example

6. help <command>

Shows the list of valid commands or the detail of the chosen commands

• Usages for help command:
  • help Shows the list of all valid command for the program
  • help <command> command options: 'show' or 'compress' or 'compressFiles' or 'detail' or 'delete'

Examples

(.venv) root@root:~/CompJPEG$ ./main.py
(CompJPEG) help

Documented commands (type help <topic>):
========================================
EOF  compress  compressFiles  delete  detail  help  quit  show

(CompJPEG) detail
ERROR: No image id found
(CompJPEG) compressFiles type=text path=./example/example_text.txt
(CompJPEG) detail
         Image ID: mountain-e56cf50f.jpeg
         Resolution: 320 X 180
         Time Taken: 0m:0s
         Quality: 55
         | ORIGINAL   | COMPRESSED
----------------------------------------------
    Name | mountain.jpeg | mountain-e56cf50f.jpeg
----------------------------------------------
    Size | 16.4KB     | 10.2KB
----------------------------------------------

(CompJPEG) detail id=landscape-881b0212.jpg
         Image ID: landscape-881b0212.jpg
         Resolution: 612 X 408
         Time Taken: 0m:1s
         Quality: 60
         | ORIGINAL   | COMPRESSED
----------------------------------------------
    Name | landscape.jpg | landscape-881b0212.jpg
----------------------------------------------
    Size | 49.2KB     | 43.8KB
----------------------------------------------

(CompJPEG) delete id=landscape-881b0212.jpg remove=True
(CompJPEG) detail id=landscape-881b0212.jpg
ERROR: Could not found object with id:	landscape-881b0212.jpg
(CompJPEG) help show

        Pulls out a window showing the image file requested
        by the user

        USAGE: show id=image_id mode=[ compressed | original | compare ]
        USAGE: show mode=[ compressed | original | compare ]
        USAGE: show id=image_id
        USAGE: show

        Arguments
        ---------
        id : [default=last_object]
            The id of the image that was compressed
        mode : [default=compressed]
            Must be a key-value pair that shows the image to
            display
            compressed:
                displays the compressed image of the given image_id
            compare:
                displays the compressed and original side by side
            original:
                displays the input image file of the image_id
(CompJPEG) quit
(.venv) root@root:~/CompJPEG$
(.venv) root@root:~/CompJPEG$ echo "detail id=car-key-710fc093.jpg" | ./main.py
(CompJPEG)       Image ID: car-key-710fc093.jpg
         Resolution: 612 X 408
         Time Taken: 0m:1s
         Quality: 85
         | ORIGINAL   | COMPRESSED
----------------------------------------------
    Name | car-key.jpg | car-key-710fc093.jpg
----------------------------------------------
    Size | 66.4KB     | 56.1KB
----------------------------------------------

(CompJPEG) (.venv) root@root:~/CompJPEG$
(.venv) root@root:~/CompJPEG$ deactivate
root@root:~/CompJPEG$

Authors

Binael Nchekwube -Github | Twitter | LinkedIn

License

Public Domain. No copy write protection.