- unsigned stream_idx, int64_t input_first_pts, int64_t input_second_pts,
- float alpha, int secondary_stream_idx = -1, int64_t secondary_inputs_pts = -1,
- float fade_alpha = 0.0f); // -1 = no secondary frame.
+ FrameOnDisk frame1, FrameOnDisk frame2,
+ float alpha, FrameOnDisk secondary_frame = {}, // Empty = no secondary (fade) frame.
+ float fade_alpha = 0.0f);