MP3 decoder and associated utilities

MP3 decoder for various build targets. Build targets include at the moment Linux/x64 and WebAssembly.

Quickstart

Prerequisites

• Node.js
  • Consider installing via nvm
• CMake
• GCC
  • For Linux building
• Emscripten
  • For WebAssembly building, tested with version 3.1.6

Install dependencies

pip install gcovr
npm i

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Decode MP3 file using Node + WebAssembly

Build WebAssembly target

npm run wasm-build

Execute in Node

npm run decode -- --input=<input.mp3>  --output=<output.pcm>

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Decode MP3 file using Linux/x64

Build target

npm run x64-build

Decode using command line binary

build/bin/mp3streamapp -stream <input.mp3> -out <output.wav> -wave-out

Run unit tests with memory checking enabled and generate code coverage report

npm run x64-build -- --type=Debug --folder=build-debug
npm run x64-tests -- --folder=build-debug --memcheck
npm run x64-coverage -- --folder=build-debug

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Troubleshooting tips

• Run in Debug mode

• Add following line (example only) to build-wasm/bin/mp3dec_static.html

  • Module.onRuntimeInitialized=function() {console.log(Module); console.log(Module._openDecoder());}

• Serve content using npm run serve-build

• Goto http://localhost:4200/mp3dec_static.html on browser

• npm run js-beautify -- build-wasm/bin/mp3dec_static.js -r (unminify js file)

• node main.js --input=.mp3 --output=test.raw (decode)

• ffplay -f s16le -ar 44k -ac 2 test.raw (play with ffplay)