Runway Ruby Rebuilds SDR Video Into True HDR

Runway has introduced Ruby, a specialized model designed to convert standard dynamic range (SDR) video into true 16-bit high dynamic range (HDR) footage. Available for Max and Enterprise subscribers, the tool processes uploaded or Runway-generated clips up to 30 seconds long. Instead of simply stretching existing color values like traditional inverse tone mapping, Ruby uses generative AI to reconstruct lost highlight and shadow details, outputting professional formats like 16-bit EXR sequences, 10-bit and 12-bit ProRes, and HEVC in BT.2020 color with PQ or HLG transfer functions.

Developers can access the model via the API endpoint POST /v1/video_to_hdr. Billing is calculated per second of output at the source's native resolution. Ruby costs 20 credits per second, which translates to $0.20 per second or roughly $6 for a 30-second clip, given that credits cost $0.01 each. For source files larger than 4 megapixels, such as 4K video, the price increases to 40 credits per second. This pricing places Ruby between Runway's flagship Gen-4.5 model at 12 credits per second and its Aleph 2.0 model at 28 credits per second. Users can also generate HDR directly from Gen-4.5 or Aleph 2.0 for a surcharge of 20 credits per second, or 40 credits above 4 megapixels.

For video editors and colorists, Ruby solves a major bottleneck in modern production pipelines. Most AI video generators output 8-bit SDR files, which look out of place when intercut with high-end camera footage graded for HDR streaming. By synthesizing realistic light data in clipped highlights and crushed shadows, Ruby allows synthetic footage to hold up under rigorous color grading. This release positions Runway to compete directly with existing AI-driven HDR conversion tools like Topaz Hyperion and LTX Studio, offering a unified pipeline from initial prompt to final HDR master.