ebml-block

const fs = require('fs'); const ebml = require('ebml'); // Required for decoding the overall EBML stream const ebmlBlock = require('ebml-block'); // The library: parses the raw Block data // Initialize an EBML Decoder from the 'ebml' package. // This decoder processes the high-level EBML structure of a file like .mkv or .webm. const decoder = new ebml.Decoder(); // Listen for 'data' events. Each 'chunk' represents an EBML element found. decoder.on('data', function (chunk) { // We're interested in 'Block' or 'SimpleBlock' elements, which contain // the actual video/audio frame data along with metadata like timecodes. if (chunk[1].name === 'Block' || chunk[1].name === 'SimpleBlock') { // The 'data' property of the element is a Buffer containing the raw block. // Pass this Buffer to ebmlBlock for detailed parsing. const block = ebmlBlock(chunk[1].data); console.log('Parsed EBML Block:', block); console.log(` Track Number: ${block.trackNumber}`); console.log(` Timecode (ms): ${block.timecode}`); console.log(` Keyframe: ${block.keyframe}`); console.log(` Number of frames in block: ${block.frames.length}`); } }); decoder.on('error', (err) => { console.error('EBML Decoder encountered an error:', err.message); }); decoder.on('end', () => { console.log('Finished processing EBML stream.'); }); // To run this, ensure 'media.mkv' exists in the current directory or provide a valid path. // This pipes an MKV file stream through the EBML decoder. // The decoder then emits 'data' events for ebml-block to process. fs.createReadStream('media.mkv').pipe(decoder);