How to compose music for a video in your browser

ComposerNow is a scratchpad for scoring a video fast. Drop the video in, pick an instrument, press ⌘Space and play along as it runs. Every take becomes a clip on its own track that you can slide into place, trim at either end, fade in and out, mute, solo and undo. When it sounds right, render one WAV the exact length of the video and hand it to whatever makes the final cut.

Step by step

1. Drop a video onto the viewer. Wide or vertical, any format your browser plays.
2. Add an instrument track and choose a sound from the picker. Play it with your computer keys or a MIDI keyboard (Connect MIDI, top right).
3. Click the ruler where the scene starts, press ⌘Space, play, press ⌘Space again. The take sits on the track where you started it.
4. Drag clips to line them up with the picture, or tap [ and ] to nudge them. Drag the ends to trim, drag the top corners to fade. Backspace deletes, ⌘Z undoes.
5. Layer more tracks, or add a Mic track for a voice or a real instrument (headphones on).
6. Press Render WAV. The file starts at frame zero and runs to the end of the video, so it lines up without trimming.

Keyboard shortcuts

• Space play / pause
• ⌘Space or ⇧Return start / stop recording on the selected track
• Return back to the start (stops playback or a take first)
• ⌘Z undo · ⇧⌘Z redo
• Z (with a clip selected) or ⌘E or the ✂ Split button: cut the selected clip, or the clip under the playhead on the selected track, at the playhead. With no clip selected, Z plays C3 again
• ⌘S download the selected clip as its own WAV
• [ ] nudge the selected clip 0.1 s (Shift 1 s, Option 0.01 s); with no clip selected they play F5 and G5
• Backspace delete the selected clip · Esc deselect
• Markers: the ⚑ Marker button or a double-click on the marker bar adds one; click to jump, drag to move, double-click to rename, ✕ to delete. ⏮ and ⏭ jump between markers (or to the start and end when there are none)
• ← → move the playhead 1 s (Shift 5 s, Option 0.1 s)
• ⌘ + scroll zooms the timeline · Shift is the sustain pedal · ↑ ↓ semitone

Questions

Does my video get uploaded?

No. The video, every take and the final WAV are made and kept inside your browser tab. Close the tab and they are gone, so render before you leave.

Which instruments can I play?

The same ones as hitjam.io: grand piano, electric piano, pads and synths, basses, three drum kits, xylophone, marimba, glockenspiel, trumpet, trombone, tuba and three string sections. Play them with your computer keys or any MIDI keyboard.

What does the render contain?

One stereo WAV as long as your video, starting at its first frame, with every track mixed at its fader level. Tick "+ video sound" to mix the video’s own audio in; leave it off to get the music alone for your video editor.

Can I record my voice or a real instrument?

Yes. Add a Mic track, put on headphones so the video’s sound stays out of the microphone, and press Enter. The take lands on the track as a clip.