@phi-ag/rvt/dist/thumbnail.js

Parse Revit file format

const findMarker = (data) => {
    const imageMarker = [0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a];
    for (let i = 0; i < data.length - 6; i++) {
        if (data[i] === imageMarker[0] &&
            data[i + 1] === imageMarker[1] &&
            data[i + 2] === imageMarker[2] &&
            data[i + 3] === imageMarker[3] &&
            data[i + 4] === imageMarker[4] &&
            data[i + 5] === imageMarker[5]) {
            return i;
        }
    }
};
export const parsePreview = (data) => {
    const marker = findMarker(data);
    if (!marker)
        throw Error("Failed to find preview image marker");
    return new Blob([data.subarray(marker)], {
        type: "image/png"
    });
};
export const thumbnail = async (cfb) => {
    const entry = cfb.findEntry("RevitPreview4.0");
    if (!entry)
        throw Error("RevitPreview4.0 not found");
    return parsePreview(await cfb.entryData(entry));
};
export const tryThumbnail = async (cfb) => {
    try {
        return { ok: true, data: await thumbnail(cfb) };
    }
    catch (e) {
        if (e instanceof Error)
            return { ok: false, error: e.message };
        throw e;
    }
};