Big Image Recorder

This Unity Recorder plugin captures an image sequence at a higher resolution than the maximum texture size. Want to output your scene at 100,000 x 100,000 pixels? You got it friend.

To do this it divides the camera's projection matrix into tiles and saves the renders as individual images to stitch together.

At present this stitching operation is left up to you (but see "Image Stitching" below for recommendations).

Installing

Add this package to your project using the Unity Package Manager (UPM).

1. Open Window > Package Manager
2. If it's not already in your project, install Recorder from the Unity Registry
3. Click "+" in the top-left corner and choose "Add package from git URL..."
4. Enter https://github.com/mminer/big-image-recorder.git

You can also clone this repository and point UPM to your local copy. Do this if you want to modify the source code.

Using

1. Open Window > General > Recorder > Recorder Window
2. Click "Add Recorder" and choose "Big Image Sequence"
3. Enter the tag of your target camera (or keep the default to use your main camera)
4. Enter your desired output size, number of rows and columns, and start recording

Recorder spits out multiple images per frame, one for each "tile". By default these are named image_<Frame>_<Tile Row>-<Tile Column>.png, e.g. image_0003_01-01.png.

Image Stitching

ImageMagick is one option to stitch the image tiles together into a final image.

# Stitches together a frame of two columns.
montage -mode concatenate -tile 2x *.png out.png

To run this automatically, enter the absolute path to the executable in the "Stitch Command" field and its arguments (i.e. -mode ...) in "Arguments". For example, if you install ImageMagick on macOS using Homebrew, enter /usr/local/bin/montage as the command.

The arguments can contain the same wildcards as the file name. Use these to specify the frame, rows, and columns, e.g. -mode concatenate -tile <Columns>x image_<Frame>*.png <Frame>.png.

Caveats

Dividing a projection matrix into tiles and stitching together the results works poorly with post-processing effects. Vignette, for example, gets applied after the camera renders and leaves noticeable seams where the edges meet.

For best results, turn off all screen space effects.