Parse only the LAS header (first 227+ bytes) for range-based access.

Returns a LasHeaderInfo with metadata needed to compute point offsets. This is the core COPC concept: read the header once, then fetch individual points on demand using Range headers.

Arguments

• bytes - At least 230 bytes from the beginning of a LAS file.

Example

// In the browser:
const response = await fetch("data.las", { headers: { Range: "bytes=0-229" } });
const headerBytes = new Uint8Array(await response.arrayBuffer());
const info = parseLasHeaderOnly(headerBytes);
console.log(`File has ${info.numPoints()} points`);

// Fetch point 42:
const offset = computeLasPointOffset(info, 42, info.pointFormatId());
const pointResponse = await fetch("data.las", {
    headers: { Range: `bytes=${offset}-${offset + info.pointRecordLength() - 1}` }
});
const pointBytes = new Uint8Array(await pointResponse.arrayBuffer());
const point = parseLasPointAt(pointBytes, 0, info.pointFormatId());
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