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Spray Paint

Spraypaint is a compression/decompression tool that uses huffman codes as a base for encoding and decoding data.

Usage: ./spray_paint <flag> <filename> <output>

spray_paint is a file compression and decompression tool.

Arguments:
  <flag>       d or c for [d]ecompress or [c]ompress.
  <filename>   The name of the file to compress or decompress.
  <output>     The name of the output file.

Examples:
  ./spray_paint c example.txt example.spz
  ./spray_paint d example.spz example.txt

To build the project from source (using ninja, I've only tested with ninja):

git clone [email protected]:devanbenz/spray-paint.git && cd spray-paint

mkdir -p cmake-build-debug && cd cmake-build-debug

cmake .. -G "Ninja" -DCMAKE_BUILD_TYPE=Debug

ninja

File Structure

Compressed SprayPaint file's contain the following structure as binary data:

   56 bytes          57...n bytes          1 byte   
┌──────────────┬───────────────────────┬───────────┐
│              │                       │           │
│   Decoder    │        Data           │  Padding  │
│    Tree      │                       │           │
└──────────────┴───────────────────────┴───────────┘

Decode Tree is a huffman code tree where each leaf node is a value from the source data.

Data is the data in raw bits encoded by the decoder tree.

Padding since data can only be stored in byte format on disk (8 bits) sometimes we will have a number of bits encoded that are not divisible by 8. This final byte stored the amount of padded 0's for our final byte of data.