Use QuickTime to create a "tiled video wall" or "video mosaic"

Crafting a Tiled Video Wall with QuickTime and AppleScript

Learn how to create a dynamic 'video mosaic' or 'tiled video wall' effect using QuickTime Player 7 Pro and AppleScript on macOS, ideal for presentations or artistic displays.

Creating a 'tiled video wall' or 'video mosaic' effect involves arranging multiple video clips into a single, larger composite video. While professional video editing software offers advanced features for this, you can achieve a surprisingly effective result using QuickTime Player 7 Pro and AppleScript on macOS. This method is particularly useful for users who need a quick, programmatic way to combine videos without investing in complex editing suites. This article will guide you through the process, from preparing your videos to automating the tiling with AppleScript.

Prerequisites and Setup

Before diving into the scripting, ensure you have the necessary tools and understand the basic concepts. This approach relies heavily on QuickTime Player 7 Pro, which, while older, offers robust AppleScript support for video manipulation. QuickTime Player X, the default player in modern macOS versions, lacks the extensive scripting capabilities required for this task.

1. Install QuickTime Player 7 Pro

QuickTime Player 7 Pro is essential. If you don't have it, you might find it on older macOS installation discs or by searching Apple's support archives. You'll need a QuickTime 7 Pro registration key to unlock its advanced features, including AppleScript control over video tracks and dimensions.

2. Prepare Your Video Clips

Gather the video clips you wish to tile. For a clean mosaic, it's best if all clips have the same aspect ratio and ideally, the same resolution. This simplifies the calculation of positions and sizes. Name your files systematically (e.g., video1.mov, video2.mov) for easier scripting.

3. Understand the Tiling Logic

The core idea is to open each video in QuickTime Player 7, scale it down, and then position it within a new, larger 'canvas' video. AppleScript will automate these steps, calculating the correct scale and position for each tile based on your desired grid layout (e.g., 2x2, 3x3).

The AppleScript Automation Logic

The AppleScript will perform several key operations: opening videos, getting their dimensions, calculating new dimensions and positions for the tiled layout, and then assembling them into a new QuickTime movie. The process involves creating a 'master' video that acts as the canvas, then adding each individual video as a new track to this master, scaling and positioning it accordingly.

flowchart TD
    A[Start] --> B{Define Grid & Video Paths}
    B --> C[Create New Master Movie]
    C --> D{Loop Through Each Video File}
    D --> E[Open Video in QuickTime 7 Pro]
    E --> F[Get Video Dimensions]
    F --> G[Calculate Scaled Size & Position]
    G --> H[Add Video as Track to Master Movie]
    H --> I[Set Track Dimensions & Position]
    I --> J{More Videos?}
    J -- Yes --> D
    J -- No --> K[Save Master Movie]
    K --> L[End]

    subgraph QuickTime Player 7 Pro Actions
        E -- QT7 --> F
        H -- QT7 --> I
    end

Workflow for creating a tiled video wall using AppleScript and QuickTime Player 7 Pro.

AppleScript for Tiled Video Creation

Here's a comprehensive AppleScript that demonstrates how to create a 2x2 tiled video wall. You can adapt this script for different grid sizes by modifying the num_cols and num_rows variables and adjusting the loop logic. Remember to change the source_folder path to where your video files are located.

set source_folder to (path to desktop folder as text) & "TiledVideos:"
set output_file to (path to desktop folder as text) & "TiledVideoWall.mov"

set num_cols to 2
set num_rows to 2
set tile_width to 640 -- Desired width of each tile
set tile_height to 360 -- Desired height of each tile

set final_width to num_cols * tile_width
set final_height to num_rows * tile_height

tell application "QuickTime Player 7 Pro"
	activate
	set new_movie to make new movie
	set dimensions of new_movie to {final_width, final_height}

	set video_files to every file of folder source_folder whose name extension is "mov"
	set file_count to count of video_files

	if file_count is not (num_cols * num_rows) then
		display dialog "Warning: Number of video files does not match grid size." buttons {"OK"} default button 1 with icon caution
	end if

	set current_tile_index to 0
	repeat with a_file in video_files
		set current_tile_index to current_tile_index + 1
		set file_path to (source_folder & (name of a_file)) as alias

		set source_movie to open file_path
		set source_track to first video track of source_movie

		-- Calculate position
		set col_index to ((current_tile_index - 1) mod num_cols)
		set row_index to ((current_tile_index - 1) div num_cols)

		set x_pos to col_index * tile_width
		set y_pos to row_index * tile_height

		-- Add track to new movie
		add source_track to new_movie
		set added_track to last video track of new_movie

		-- Scale and position the track
		set dimensions of added_track to {tile_width, tile_height}
		set origin of added_track to {x_pos, y_pos}

		close source_movie saving no
	end repeat

	save new_movie in file output_file
	close new_movie
	display dialog "Tiled video wall created successfully!" buttons {"OK"} default button 1 with icon note
end tell

AppleScript to create a 2x2 tiled video wall from files in a specified folder.

Customizing and Extending the Script

The provided script is a foundation. You can customize it further to suit more complex needs. Consider these enhancements:

1. Dynamic Grid Sizing

Instead of hardcoding num_cols and num_rows, you could prompt the user for these values or calculate them based on the number of available video files (e.g., find the closest square root).

2. Padding and Borders

To add spacing between tiles, adjust the x_pos and y_pos calculations to include a padding value. You might also need to increase the final_width and final_height of the master movie accordingly.

3. Audio Handling

The current script only handles video tracks. If you need audio, you'll need to decide which audio track to keep (e.g., from the first video, or mix all of them). This would involve adding audio tracks similarly to video tracks, but with careful consideration for mixing and synchronization.

4. Error Handling

Improve error handling for cases where files are missing, corrupted, or QuickTime Player 7 Pro isn't running. The current script has a basic file count check, but more robust checks could be added.