HDR to SDR
HDR is rendered to SDR using exposure and Reinhard tone mapping.
Convert HDR to PAM
- In your browser
- No upload
- Private by design
What happens when you convert HDR to PAM?
Transparency
The target can store an alpha channel, but converting an opaque image does not create transparent areas. Removing a background is a separate editing step.
Lossless sample storage
Netpbm stores these samples without compression. Reducing colour, thresholding or changing maxval can still lose information before storage; text and binary representations change the layout, not its image meaning. PAM can store its supported image samples without lossy compression. This applies after rendering and sample conversion: it does not guarantee preservation of source precision, colour space or document structure, and cannot undo earlier losses.
HDR
Source
HDR
Radiance HDR / RGBE
Compression: LosslessTransparency: NoMetadata: Radiance header, EXPOSURE, FORMAT
Radiance pictures with a shared exponent for high-dynamic-range lighting values.
Explore HDR format →PAM
Target
PAM
Portable Arbitrary Map
Compression: UncompressedTransparency: YesMetadata: Header, Comments
Portable Arbitrary Map: simple uncompressed raster samples for image-processing pipelines.
Explore PAM format →Is HDR → PAM right for you?
Good choice when
- PAM fits your delivery use: Channel-aware image pipelines.
- You need an SDR delivery copy and can review its tone mapping.
- You need lossless storage of the rendered samples supported by PAM.
- You can validate the destination’s sample precision and colour interpretation.
- You need a PAM-compatible workflow that can hold transparency added in a separate edit.
Probably not when
- You need the original HDR range for relighting or grading.
- You expect lossless encoding to restore lost details or editing structure.
- You require identical samples without a defined colour and precision policy.
- You expect automatic background removal or transparency.
HDR to PAM conversion details
- HDR to SDR
- HDR is rendered to SDR using exposure and Reinhard tone mapping.
- Transparency
- The target can store an alpha channel, but converting an opaque image does not create transparent areas. Removing a background is a separate editing step.
- Lossless sample storage
- Netpbm stores these samples without compression. Reducing colour, thresholding or changing maxval can still lose information before storage; text and binary representations change the layout, not its image meaning. PAM can store its supported image samples without lossy compression. This applies after rendering and sample conversion: it does not guarantee preservation of source precision, colour space or document structure, and cannot undo earlier losses.
- Sample precision & colour
- Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
- Metadata & colour
- Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
- Compression
- HDR: Lossless → PAM: Uncompressed HDR: RLE preserves stored RGBE bytes; RGBE quantization is not exact storage of arbitrary float RGB. The .hdr format is distinct from the general concept of HDR photography. PAM: Netpbm stores these samples without compression. Reducing colour, thresholding or changing maxval can still lose information before storage; text and binary representations change the layout, not its image meaning.
- Transparency
- Transparency is replaced with white by default. Change the background in Advanced options.
- Colour depth
- HDR: 32-bit RGBE / XYZE pixel → PAM: maxval up to 65535
- HDR
- HDR: Radiometric values
- Dimensions
- Rendered image dimensions are retained within the converter limits; this tool does not offer resizing. Orientation handling depends on the source decoder.
- Metadata
- Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
Common questions
How will HDR brightness be mapped?
HDR is rendered to SDR using exposure and Reinhard tone mapping.
Will the background become transparent?
The target can store an alpha channel, but converting an opaque image does not create transparent areas. Removing a background is a separate editing step.
Does lossless output mean an unchanged source?
Netpbm stores these samples without compression. Reducing colour, thresholding or changing maxval can still lose information before storage; text and binary representations change the layout, not its image meaning. PAM can store its supported image samples without lossy compression. This applies after rendering and sample conversion: it does not guarantee preservation of source precision, colour space or document structure, and cannot undo earlier losses.
Are bit depth and colour values guaranteed to match?
Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.
Will metadata and colour profiles be retained?
Pixel conversion only. Original EXIF, GPS, XMP and ICC profiles are not copied; processing uses 8-bit display pixels.