What is the Corona Image Editor?
- 1. Corona Image Editor
- 2. CXR Image Format
- 3. Example Uses
- 4. Batch Editing CXR Images - This explains how to edit multiple CXR files at once (for example, apply one post-processing or LightMix preset to 100 frames of an animation).
The Corona Image editor (CIE in short) is included in the Corona installer and by default it installs into:
- 3ds Max - C:\Program Files\Corona\Corona Renderer for 3ds Max\Image Editor
- Cinema 4D - C:\Program Files\Corona\Corona Renderer for Cinema 4D\Image Editor
It also creates a desktop shortcut when installed.
Note: in Corona 3 and older, CIE was installed into the root folder C:\Program Files\Corona
CIE is a portable, standalone application that allows loading a Corona EXR (.cxr) file and applying all post-processing operations which are available in the Corona VFB to it, including adjusting LightMix, running Denoising, LUTs, bloom and glare, without the need to re-render. All of this is done without running any 3D software. It can be seen as a standalone version of the Corona VFB with extended functionality.
The CIE user interface is inspired by the Corona VFB, sharing its look and feel. Below are some features and benefits of using CIE:
- Lower system requirements than working with an image inside any 3D software - it can be run and used on a less powerful computer.
- It is not necessary to have a scene loaded while you are working with your images, so you can denoise Corona renders outside of the rendering process, reducing the memory requirements significantly.
- All LightMix and post-processing settings can be easily shared between the VFB in any host application and the CIE.
- No need to copy settings manually: CXRs from the VFB are automatically loaded with them.
- It also works with regular, non-Corona EXRs (in Float format). It is possible to add bloom and glare to them, apply your tone mapping settings, LUT, etc. Denoising and LightMix are not available for such EXRs because they do not have the necessary “hidden” auxiliary data.
- Supports drag-and-drop to quickly load the images.
- Saves to EXR, PNG, JPG, JPEG, BMP, HDR, IFF, JP2, J2K, RLA, SGI, TGA, TIF/TIFF
- You can associate the CIE with EXR and CXR files and open them just by double-clicking.
- Ctrl+O and Ctrl+S can be used for fast image opening and saving.
- It is a portable application, works with just unpacking, no installation is necessary (license activation is required, though).
- It is free with a regular Corona license.
The Corona EXR image format (cxr) is almost identical to the standard EXR format, with the one difference being the additional data that is saved within the file. This additional data includes all render elements (also ones which are not exposed to the user, which are used during the denoising process), and rendering statistics such as rays per second, noise level, Corona version, etc. To save an image in Corona EXR format either:
- In both 3ds Max and Cinema 4D: press and hold the Save button in the Corona VFB and select "Save CXR" from the dropdown menu.
In 3ds Max only: go to Render Setup > Scene and press the "Save CXR..." button.
- In 3ds Max only: save the file as .cxr using the standard 3ds Max "save as" dialog.
Note: you need to have the Beauty render element selected in the dropdown list in the VFB. If any other item is selected, only that single element will be saved in the CXR format, which will not allow for using the LightMix in CIE.
- If you click the "Save" button in the upper left corner, this will save only your currently visible render element ("render pass" in Cinema 4D) in the format of your choice. So if you select the Beauty element and click "Save", it will save only the beauty element, without any other elements such as the LightMix, even if you select the CXR format.
- If you click and hold on the "Save" button and select "Save all", this will save each render element as a separate file using the format of your choice.
- If you click and hold on the "Save" button and select "Save CXR", this will store all the information from the VFB (all render elements, including the LightMix, tone mapping, denoising data, etc...) inside a single CXR file. This file can be used to resume rendering later, post-process in the Corona Image Editor, perform denoising later, and so on.
- Alternatively, in 3ds Max you can click "Save CXR..." in Render Setup > Scene and this has the same effect as clicking "Save CXR" in the VFB.
1. Denoising a CXR image
If you saved your image in the CXR format without performing the actual denoising, and with the "gather data for later" denoising option enabled, you can open this image later in the CIE and perform the denoising there. To do this, simply load your image into CIE, expand the "Denoising" rollout in the "Post" tab, and choose either "Denoise" for automatic denoising, or "Custom denoise..." to specify which render elements should be denoised, and what settings to use:
2. Using LightMix
You can save an image with all LightMix layers included and then adjust the LightMix settings in CIE. To do this, simply load your image and select the "LightMix" tab. You will see exactly the same settings as in the Corona VFB, including the options to save and load LightMix presets:
CoronaImageBatch is a script for batch image processing. It can be used to process multiple images at once using custom .conf files, which can be saved using the GUI version of CIE, or edited manually. Help file and an example CXR file are included in the below ZIP archive.
Example use: save 100 frames of an animation in .cxr format, perform specific post-processing operations and denoising on all of them, output all of them in .png format.
- For Corona Renderer 5 and newer: CoronaImageBatchV5
- For Corona Renderer 3 and 4: CoronaImageBatchV3
- For Corona Renderer 2: CoronaImageBatchV2
Note: you can run the CoronaImageCmd.exe application with additional command line parameters:
This will print a list of various use cases of batch editing and short explanations of how to make them work.
This will print general help.