XO3D Labs · Local image workflow
HDR to JPG and PNG
Make an ordinary display preview from a Radiance RGBE HDR image. Adjust exposure, compress the highlights or clip them, then download an 8-bit JPG or PNG. Your source stays on your device.
Tone-map a local HDR
Choose a Radiance HDR or load the original synthetic sample.
Input: up to 64 MiB, 8192 pixels per edge and 16 megapixels. Output: original aspect ratio, up to the chosen edge, never enlarged. Reduction uses nearest sampling. JPEG uses a 0.92 browser quality setting; PNG preserves the generated SDR pixels.
Use the preview, keep the HDR master
JPG and this PNG output are low-dynamic-range previews. They cannot retain the source lighting range, replace an HDR environment for lighting, or recover HDR detail from a JPEG. Exposure is an artistic adjustment, not a calibration.
Supported encodings and colour limitations
Supports flat RGBE and modern scanline RLE in all eight axis orders. Legacy repeat encoding, XYZE, EXR, HDR video, non-square pixels, custom primaries and non-unit GAMMA are rejected. Truncated data and oversized allocations fail before export.
The stored RGBE channels are tone-mapped and encoded with the sRGB transfer curve as a display approximation. This is not a colour-managed conversion from Radiance primaries. Existing EXPOSURE and COLORCORR multipliers are reported and left baked into the stored pixel values. No white-balance, gamut conversion or metadata is carried into the output.
Reinhard applies L / (1 + L) to each exposed channel. Linear clip caps each channel at 1. Per-channel compression can change hue or saturation. Use a colour-managed HDR application when accurate luminance or colour is required.
Continue the environment workflow
Convert a panorama to cubemap faces for an SDR orientation preview, or use the HDRI exposure calculator for exposure planning. The cubemap tool accepts ordinary images; this preview conversion does not add HDR support to it.
Format reference: Radiance File Formats. The built-in gradient is an original synthetic RGBE test image, not a studio lighting asset.