Making a song video

PianoFlex can turn a MIDI file into a video that's ready to share on Instagram, TikTok, YouTube or anywhere else. The video shows the notes falling onto a full 88-key piano keyboard as they play, with the song's title at the top and, if you like, a bar for how far into the song it is. You can put a photo of your own behind the falling notes. Songs from ComposerFlex show the bass, the inner part and the melody in their own colors. You hear the song on the piano you've chosen, exactly as Render to audio would play it.

Making videos is part of the full version. In demo mode, Make video… says "Make video is in the full version." and makes nothing.

Making a video

1. Open a MIDI file, as for playing it (see Playing, rendering and recording).
2. Choose the piano and set its sound as you want it to be heard: the preset, the sliders, the room and any layers.
3. Click Make video…, beside Render to audio, or press Shift+W.
4. The Make a song video box opens. At the top it shows how long the video will be. Everything in it is already filled in, so you can click Make (or press Enter) straight away, or change any of the choices below first.
5. The box stays open while the video is made: "Making your video of" the file's name, with a bar, how far it has got and how long is left, for example "40%, 0:15 left". Click Cancel video to stop: nothing is saved. Or click Close and go on playing: Make video… then shows how far it has got, for example "Making video 40%…", and clicking it opens the box again.
6. When the video is ready, the box says Video saved and gives the video's full place on your PC. Click on it to copy it (the box says "Copied."), or press Ctrl+C. Click Open to watch the video, or Open in File Explorer to see it in its folder, selected, ready to copy to your phone or upload. Click Close when you're done.

If you closed the box while the video was being made, the yellow line gives the video's full place when it's done, with Open in File Explorer beside it.

A one-minute song usually takes about 15 to 20 seconds.

Where the videos are saved

Videos you make in PianoFlex are saved in the PianoFlex folder in your Documents, in a folder called videos, beside the recordings folder. Each one is named after its title, with spaces as underscores, and the date, for example sunday_morning_2026-10-20.mp4. It's an .mp4 file, which phones, browsers and every video site can play.

If your Documents folder is kept in OneDrive, your videos are copied there too, which takes room in your OneDrive: about 60 MB for each minute of video.

The choices in the box

• Title: the text at the top of the video. At first it's the MIDI file's name, with any underscores shown as spaces: a file called sunday_morning.mid gives "sunday morning". Type over it to give your song its real title.
• Under the title: a line of your own under the title, for example your name or your channel. Leave it empty if you don't want one.
• Colors: Dark, the colors of our own videos, on a dark background; Warm, in coral, gold and cream on a dark brown; or Light, on a light gray background, for feeds that look better bright.
• Shape: Tall, for phones (1080 × 1920 pixels), or Wide, for YouTube (1920 × 1080), which also suits a website.
• Background: None, the plain background of the colors you chose, or Choose picture… to put a photo of yours behind the falling notes. Once you've chosen one, its file name shows between the two, and None takes it away again. See A picture behind the notes below.
• Picture position (with a picture): which part of the picture the video shows. See below.
• Note color (with a picture): the color of the falling notes and the lit keys. See below.
• Show a progress bar at the top: a line under the title that fills as the song plays, so viewers can see how far into the song they are. YouTube Shorts shows no timeline of its own, so it's ticked at first. Untick it to leave it out.
• Show "Made with PianoFlex" and flexmusiclabs.com along the bottom: a line that tells viewers how the video was made. Untick it to leave it out.
• Show "Made with PianoFlex" and flexmusiclabs.com at the end, for 3 seconds: a last picture with PianoFlex's icon. Untick it to leave it out, and the video ends two seconds after the last note.

Click Cancel, or press Esc, to close the box without making a video. PianoFlex remembers your choices for the next video.

The "Made with PianoFlex" line and the picture at the end are there to help other people find PianoFlex, and you're free to take them off. Your music and your videos are yours: nothing is owed to us for them. See Demo mode and your license.

A picture behind the notes

Click Choose picture… and pick a JPEG or PNG photo on your PC. It fills the space behind the falling notes, from under the title down to the keyboard, as it is: PianoFlex doesn't dim, blur or stretch it. The title and the keyboard stay on the plain background, so they're always easy to read. A photo taken on its side on a phone is turned upright, as your phone shows it. In a PNG with see-through parts, the background of the colors you chose shows through.

Picture position. Most pictures are a different shape from the space they fill, so part of them is left out: the sides of a picture wider than the space, or the top and bottom of one taller than it. In Tall the space is nearly square; in Wide it's wide. The small copy of your picture in the box shows the part the video will show, with the rest dimmed. Move the slider, from Left to Right (or Top to Bottom), to choose which part; Center puts it back in the middle. You can also click the slider and use the arrow keys, or Home and End to go to either end. Tall and Wide each keep their own position. If your picture is exactly the shape of its space, the box says "The whole picture is shown." To keep the most of your photo, choose one shaped like the space: a nearly square photo for Tall, a wide one for Wide.

Note color. With a picture, every falling note and every lit key is one color, so the notes stand out from your photo in one clear color.

• From the picture (the first choice): PianoFlex starts on a vivid color based on your picture. To choose another, click anywhere on the small copy of your picture, and the notes take the color there. Or hold the mouse button down and drag over the copy: the color changes as you go, and the one under the pointer when you let go is kept. If you drag past the picture's edge, the color stays at the edge's. The small square beside the row shows the color.
• Choose color…: Windows' own color box, opening on the current color.
• From Colors: the notes in the three colors of Dark, Warm or Light, as without a picture.

A color that stands out from the part of the picture the notes fall over is easiest to see, especially on a phone. If the notes get lost in your photo, try Choose color…, or From Colors.

PianoFlex remembers the position and the note color you chose for each picture, and brings them back when you choose that picture again.

If a picture can't be used, the box says why. A picture you've just chosen leaves the background as it was. A remembered picture that has been moved, deleted or can no longer be read is taken off, and the background is None:

• "The background picture beach.jpg isn't there any more." (it has been moved or deleted since);
• "The background picture beach.jpg is on the network. Copy it to this PC first.";
• "The background picture beach.jpg couldn't be read. Choose a JPEG or PNG photo.";
• "The background picture beach.jpg is too large. Choose one under 100 megapixels and 50 MB."

The picture is only read. PianoFlex doesn't change, move or copy it, and nothing of it is sent anywhere.

The whole song, as it is

The video is always the whole song, from its first note to its last, and its sound fades out gently at the very end. PianoFlex doesn't cut it, change its speed or change its notes. To make a shorter video, use a shorter MIDI file. With ComposerFlex, set Minutes lower before you compose the song.

The sound is set to the level that video sites play at (−16 LUFS), so you don't have to adjust it. The Files: setting is for audio files only and doesn't change the video.

Songs from ComposerFlex

In ComposerFlex, select a song on the Archive tab and click Make video… there. ComposerFlex's own box has the same choices, the picture included. If PianoFlex is running, it makes the video in the background with the piano it's set to now, and its yellow line says "Making a video for ComposerFlex" with how far it has got. ComposerFlex shows the rest, so you don't need to come to PianoFlex. The video then says "Made with ComposerFlex + PianoFlex", and it's saved in ComposerFlex's own videos folder. See With ComposerFlex.