/**
 * Video Merger for Director Mode
 *
 * Concatenates multiple MP4 video buffers into a single MP4 using FFmpeg's
 * concat demuxer for lossless concatenation when codecs match.
 *
 * Uses the shared FFmpeg adapter for binary resolution, temp file management,
 * and process execution — following the adapter pattern in `adapters/tts/`.
 *
 * @module adapters/video/videoMerger
 */
/**
 * Merge multiple MP4 video buffers into a single MP4.
 *
 * Uses FFmpeg concat demuxer for lossless concatenation. If codecs don't match
 * (unlikely since all clips come from Veo), falls back to re-encoding with H.264.
 *
 * @param videoBuffers - Array of MP4 video buffers to concatenate in order
 * @returns Merged MP4 video buffer
 * @throws {VideoError} If merge fails or no valid buffers provided
 */
export declare function mergeVideoBuffers(videoBuffers: Buffer[]): Promise<Buffer>;