PNG to EXR: conversion guide

What happens when you convert PNG to EXR?

Animation becomes a still

An animated PNG has a timed sequence; EXR is a still-image destination in this workflow. A still export loses motion and timing. Frame choice, blending and disposal must be defined by the future engine; a first-frame export is not promised.

HDR display encoding

The source can carry HDR information and EXR has HDR-capable variants. Working radiometric values and display-referred HDR are different representations. Range, primaries, transfer function and signalling must be mapped explicitly; the future engine may instead produce SDR. HDR preservation is not promised by format support.

Encoding mode

EXR supports lossy and lossless codecs. Choose one for the sample types and required precision; .exr alone does not guarantee exact channel preservation. EXR permits different encoding modes or container representations. Its format name alone does not promise lossless output, a quality setting or a size reduction. The future engine must choose a supported codec and sample representation; inspect the target’s compression notes below.

PNG

Source

PNG

Portable Network Graphics

Compression: LosslessTransparency: YesMetadata: Exif, ICC, Text

Lossless raster images with precise edges and optional transparency. The PNG standard also defines APNG animation.

Explore PNG format →

EXR

Target

EXR

OpenEXR

Compression: Lossy & losslessTransparency: YesMetadata: Typed header attributes, Chromaticities

HDR raster data for rendering and compositing, with named channels and lossless or lossy codecs.

Explore EXR format →

Is PNG → EXR right for you?

Good choice when

EXR fits your delivery use: Render passes & HDR compositing.
You want a still illustration from an animated source.
You need HDR-capable delivery and can validate its encoding and colour signalling.
You need a transparency-capable destination and will check its supported variant.

Probably not when

Motion, frame timing or loop behaviour must survive.
You require guaranteed scene-linear values or HDR appearance.
You assume format-level alpha support guarantees matching transparent edges.
You need a guaranteed quality or file size before encoder settings exist.

PNG to EXR conversion details

Animation becomes a still: An animated PNG has a timed sequence; EXR is a still-image destination in this workflow. A still export loses motion and timing. Frame choice, blending and disposal must be defined by the future engine; a first-frame export is not promised.
HDR display encoding: The source can carry HDR information and EXR has HDR-capable variants. Working radiometric values and display-referred HDR are different representations. Range, primaries, transfer function and signalling must be mapped explicitly; the future engine may instead produce SDR. HDR preservation is not promised by format support.
Transparency representation: Both format profiles allow transparency, but this does not promise identical alpha representation. Source variants, target channel precision and alpha interpretation matter. The future encoder must explicitly carry or convert transparency; merely choosing EXR guarantees no alpha transfer.
Encoding mode: EXR supports lossy and lossless codecs. Choose one for the sample types and required precision; .exr alone does not guarantee exact channel preservation. EXR permits different encoding modes or container representations. Its format name alone does not promise lossless output, a quality setting or a size reduction. The future engine must choose a supported codec and sample representation; inspect the target’s compression notes below.
Sample precision & colour: Source and target sample models can differ in precision, channel layout, colour space and transfer function. Lossless compression only preserves the samples actually encoded; a precision reduction or colour conversion can already change them. The future engine defines numeric mapping, orientation and colour conversion; canonical depth facts are listed below where available.
Metadata & colour: Format support does not guarantee that an export preserves metadata or colour profiles. Retention and colour handling depend on the future converter; its engine is not implemented yet.
Compression: PNG: Lossless → EXR: Lossy & lossless PNG: PNG compression is lossless. Palette conversion, resizing or reducing bit depth before encoding can still discard information. Animation is the APNG extension included in the third edition. EXR: EXR supports lossy and lossless codecs. Choose one for the sample types and required precision; .exr alone does not guarantee exact channel preservation.
Transparency: PNG: Yes → EXR: Yes
Animation: PNG: Yes → EXR: No
Colour depth: PNG: 1–16 bits/sample → EXR: HALF 16 / FLOAT 32 / UINT 32
HDR: PNG: Third-edition signalling → EXR: Floating-point working values
Multiple images: EXR: Multipart
Dimensions: Pixel dimensions, page geometry, rendering resolution, resizing and orientation need explicit converter policies. The future engine has not defined them yet.
Metadata: PNG: Exif, ICC, Text → EXR: Typed header attributes, Chromaticities. Which fields are copied, rewritten or omitted will depend on the future engine; retention is not implemented yet.

Common questions

Will the output keep animation?

An animated PNG has a timed sequence; EXR is a still-image destination in this workflow. A still export loses motion and timing. Frame choice, blending and disposal must be defined by the future engine; a first-frame export is not promised.

Will HDR automatically survive in EXR?

The source can carry HDR information and EXR has HDR-capable variants. Working radiometric values and display-referred HDR are different representations. Range, primaries, transfer function and signalling must be mapped explicitly; the future engine may instead produce SDR. HDR preservation is not promised by format support.

Which compression mode will EXR use?

EXR supports lossy and lossless codecs. Choose one for the sample types and required precision; .exr alone does not guarantee exact channel preservation. EXR permits different encoding modes or container representations. Its format name alone does not promise lossless output, a quality setting or a size reduction. The future engine must choose a supported codec and sample representation; inspect the target’s compression notes below.

Are bit depth and colour values guaranteed to match?

Source and target sample models can differ in precision, channel layout, colour space and transfer function. Lossless compression only preserves the samples actually encoded; a precision reduction or colour conversion can already change them. The future engine defines numeric mapping, orientation and colour conversion; canonical depth facts are listed below where available.

Will metadata and colour profiles be retained?

PNG: Exif, ICC, Text → EXR: Typed header attributes, Chromaticities. Which fields are copied, rewritten or omitted will depend on the future engine; retention is not implemented yet.

Explore related PNG and EXR conversions.