Function handleExport

server.js:754–889

(req, res)

}

async function handleExport(req, res) {
  try {
    const body = JSON.parse((await readBody(req)).toString() || "{}");
    const session = sessions.get(body.id);
    if (!session) throw new Error("Session not found. Analyse videos first.");

    const fps = session.meta1.fps || 24;
    const trimEnd1 = clampNumber(body.trimEnd1, 0, session.meta1.frames - 1);
    const trimStart2 = clampNumber(body.trimStart2, 0, session.meta2.frames - 1);
    const blendFrames = clampNumber(body.blendFrames, 0, 48);
    const interpolate = Boolean(body.interpolate);
    const mode = body.mode === "blend" && blendFrames > 0 ? "blend" : "cut";
    const toneFrames = clampNumber(body.toneFrames, 0, 48);
    const toneScope = body.toneScope === "full" ? "full" : "join";
    const toneMatch = Boolean(body.toneMatch) && (toneScope === "full" || toneFrames > 0);
    const audioMode = ["micro_crossfade", "clean_cut", "hard_cut"].includes(body.audioMode) ? body.audioMode : "micro_crossfade";
    const output = uniqueOutputPath(outputName(session, {
      trimEnd1,
      trimStart2,
      mode,
      blendFrames,
      toneMatch,
      toneScope,
      toneFrames,
      interpolate,
      audioMode
    }));
    const end1 = Math.max(1 / fps, (session.meta1.frames - trimEnd1) / fps);
    const start2 = trimStart2 / fps;
    const blendDuration = Math.min(blendFrames / fps, Math.max(0, end1 - 1 / fps));
    const toneSource = session.analysis.tone;
    const v2ToneFilter = toneMatch ? toneFilter(toneSource, toneScope === "full" ? 1 : toneFrames, fps, toneScope) : "";

    let filter;
    if (mode === "blend") {
      const offset = Math.max(0, end1 - blendDuration);
      const expr = `A*(1-T/${blendDuration.toFixed(6)})+B*(T/${blendDuration.toFixed(6)})`;
      filter = [
        `[0:v]trim=start=0:end=${end1.toFixed(6)},setpts=PTS-STARTPTS,format=yuv420p[v0base]`,
        `[1:v]trim=start=${start2.toFixed(6)},setpts=PTS-STARTPTS,${v2ToneFilter}format=yuv420p[v1base]`,
        `[v0base]split=2[v0pre][v0fade]`,
        `[v1base]split=2[v1fade][v1post]`,
        `[v0pre]trim=start=0:end=${offset.toFixed(6)},setpts=PTS-STARTPTS[pre]`,
        `[v0fade]trim=start=${offset.toFixed(6)}:end=${end1.toFixed(6)},setpts=PTS-STARTPTS[v0b]`,
        `[v1fade]trim=start=0:end=${blendDuration.toFixed(6)},setpts=PTS-STARTPTS[v1b]`,
        `[v1post]trim=start=${blendDuration.toFixed(6)},setpts=PTS-STARTPTS[post]`,
        `[v0b][v1b]blend=all_expr='${expr}'[mix]`,
        `[pre][mix][post]concat=n=3:v=1:a=0[vout]`
      ].join(";");
    } else {
      filter = [
        `[0:v]trim=start=0:end=${end1.toFixed(6)},setpts=PTS-STARTPTS,format=yuv420p[v0]`,
        `[1:v]trim=start=${start2.toFixed(6)},setpts=PTS-STARTPTS,${v2ToneFilter}format=yuv420p[v1]`,
        `[v0][v1]concat=n=2:v=1:a=0[vout]`
      ].join(";");
    }

    if (interpolate) {