Publications | Ben Formesyn - AWS Media Services Writing

Three published articles on the AWS Media & Entertainment Blog, covering accessibility signaling in adaptive bitrate streaming, encoder configuration for broadcast-grade picture quality, and the foundations of captions and audio description in OTT workflows.

June 11, 2025

Back to Basics: Accessibility Signaling with AWS Elemental Media Services

How HLS and DASH manifests signal closed captions, subtitle tracks, and audio descriptions so that players expose them to viewers. Walks through the MediaLive, MediaConvert, and MediaPackage configuration needed to land the right CHARACTERISTICS and ROLE attributes downstream.

Why it matters: accessibility is a regulatory requirement in the UK, EU, and US. The article is aimed at architects who understand streaming but haven't had to pay close attention to the manifest-level plumbing.

MediaLive MediaConvert MediaPackage Accessibility

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January 10, 2025

Optimizing Encodes for Picture Quality with AWS Elemental MediaLive

Baseline configuration recommendations for broadcast-grade video quality. Covers codec selection (AVC, HEVC, AV1), rate control mode, GOP structure, adaptive quantization, and the trade-offs between perceptual quality and bitrate efficiency.

Why it matters: customers often inherit encoder settings that are "good enough" but miss easy quality wins. The article is a checklist you can run against an existing live channel.

MediaLive Video Encoding HEVC Picture Quality

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June 4, 2025

Back to Basics: Accessibility Services for Media

The foundational article in the accessibility series. Explains captions vs. subtitles (CEA-608/708, DVB Teletext, DVB bitmap, IMSC1), audio description as a separate track, and how broadcasters and OTT platforms have historically handled viewers with visual and hearing disabilities.

Why it matters: terminology around accessibility is confusing, and mis-signalling a caption track as a subtitle (or vice versa) will break the feature on most client devices. Start here before the signaling article above.

Accessibility MediaConvert Captions OTT

Read on AWS Blog

Full author page on AWS Blog