Converting Between Layer Formats
VERIFIED ON USD VERSION 19.03
This tutorial will walk you through converting a layer file between the different native USD file formats. USD includes three native file formats:
- .usda files – human-readable text format
- .usdc files – binary format
- .usd files – either of the above formats
The usdcat tool is useful for inspecting these files, but can also be used to convert files between the different formats using the -o option and supplying a filename with the extension of the desired output format. We'll walk through some examples of how to do this.
Table of Contents
Converting between .usda/.usdc and .usd
A .usd file can be either a text or binary format file. When given a .usd file, USD will detect the underlying format and handle the file appropriately. Converting between .usda/.usdc and .usd is just a matter of changing the extension on the file. For example:
- Given a text format file Sphere.usda, you can simply rename this to Sphere.usd. When given the .usd file, USD will detect it is a text format file. This holds true for .usdc files.
- Given a .usd file Sphere.usd that uses the text format, you can rename the file to Sphere.usda.
- Given a .usd file Sphere.usd that uses the binary format, you can rename the file to Sphere.usdc.
Converting between .usda and .usdc Files
We'll start with a simple .usda file, Sphere.usda in the USD/extras/usd/tutorials/convertingLayerFormats folder. This is a text format file, so it can be examined in any text editor or via usdcat.
To convert this file to a binary format file, we can simply specify an output filename with the .usdc extension:
This will produce a binary format file named Sphere.usdc in your current directory that contains the same contents as Sphere.usd, which we can verify using the usddiff tool:
Converting from a binary format file to a text format file and verifying the contents match can be done in the same way:
Converting between .usd Files of Different Formats
If you have a .usda or .usdc file and want to make that a .usd file without changing the underlying format, you do not need to go through usdcat. See the "Converting between .usda/.usdc and .usd" section above
If you have a .usd file of a particular format and want to convert it to a .usd file using a different format, we need to pass some additional information to usdcat via the --usdFormat option. We'll start with Sphere.usd in the USD/extras/usd/tutorials/convertingLayerFormats folder, which is a text format file. To convert this to a .usd file using the binary format:
We can then verify the contents of this binary .usd file match the contents of the original text .usd file:
Converting a binary .usd file to a text .usd file and verifying the contents match can be done in the same way: