🎬⏱️AGSoft Video Speed Ramp

🎬⏱️AGSoft Video Speed Ramp is the node for shots that should change speed. Not uniformly fast or slow - that's the simpler time-effects node - but ramping from one speed to another, the way an action sequence accelerates into its payoff or a reveal slows down as it lands.

The three controls are dead simple:

• speed_start - speed at the beginning of the ramp. Below 1 is slow-motion, above 1 is timelapse.
• speed_end - the speed the clip reaches after ramp_time and then holds.
• ramp_time - how many seconds it takes to go from start to end. Here's the subtle one: 0 means ramp across the whole clip, not "no ramp." If you want an instant change... honestly, use Time Effects instead. This node is about the gradual shift.

So a classic setup: speed_start 0.5 (slow), speed_end 2 (double speed), ramp_time 0 - the whole clip accelerates from half-speed to double. Or speed_start 1, speed_end 1 with any ramp_time - that's just a constant-speed re-encode, which is not what this node is for, but it works.

audio_mode defaults to keep_original - the original audio is copied unchanged. The tooltip is upfront that a variable ramp can leave the audio desynced from the picture, because the video's timeline is being warped while the audio isn't. For music beds and effects shots that's usually fine; for anything with sync'd dialog, be careful or mute it.

The source is the optional video input (priority) or video_path. encoder_mode (auto / nvenc / cpu) and quality_preset (fast / balanced / quality) round out the shared pack controls.

Outputs

The standard set: video_path (STRING), duration_seconds, duration_timecode, file_size_mb, width, height, fps, frames_est. Empty output_path → ComfyUI/output.

Install

Part of the comfyui-AGSoft pack. ComfyUI Manager → search "comfyui-AGSoft" → Install → restart, or:

cd ComfyUI/custom_nodes
git clone https://github.com/Art-xmaster/comfyui-AGSoft

Restart. No models; it drives the bundled FFmpeg (or a system ffmpeg on PATH).

If ramp_time trips you up - and it will - just remember the "0 = across the whole clip" rule and check the duration_seconds output after the run. It's the fastest way to see whether your ramp actually happened or you accidentally built a constant-speed clip.