FAQ on HDR in PDF

The PDF Association is pleased to announce the release of a new Application Note titled "FAQ on HDR in PDF".

The initial release of this FAQ focuses on PDF/A and PDF/X applications to help key stakeholders to understand how high dynamic range (HDR) content, such as photos from modern phones and digital cameras, works with current-generation PDF specifications and technologies.

This FAQ was prepared by the Imaging Model TWG, which is researching proposals for new technologies in PDF, including rendering, color management, new 2D raster file formats, and updating PDF transparency / blending with new capabilities. Established as an outcome of the Symposium on Advancing the PDF Imaging Model in 2023, the TWG quickly identified HDR as an essential capability in future versions of PDF.

Although popularised by television and cell phone manufacturers, HDR is not a single fixed technology. It continues to present numerous challenges for both document and web technologies, not least because HDR standards, HDR image formats, and HDR color profiles all continue to evolve while displays offer various degrees of headroom. Simply put, the display of an HDR photo on a modern cell phone is not always the same, as it depends on several factors, including ambient lighting, battery level, screen technology, and heat dissipation (caused by the locality and brightness of pixels).

In a PDF context, HDR content will overlap and/or be blended with standard dynamic range (SDR) content. Therefore, HDR vector graphics must be considered, along with concerns about backward compatibility and the need for reliable and predictable output across display and print devices.

Download the FAQ today!