Media · Circo

Adaptive streaming and the transcoding ladder

Every upload becomes a ladder of renditions, packaged once for HLS and DASH and served from the edge, so every phone gets the best stream its connection can hold. Live in production.

Architect · Engineering lead

The problem

Circo's audience watches on phones over networks that change from minute to minute. A single high-quality file would buffer; a single low-quality one would waste the creator's work. The answer is adaptive bitrate streaming, which only works if the pipeline behind it is predictable.

My role

I designed the pipeline and built and run it with my team. It carries every video on Circo in production.

How it works

Analyse the input first. Transcoding starts from an analysis of the source, so quality settings adapt to what was actually uploaded.
Build a ladder, never upscale. Each upload becomes a set of renditions from low to high resolution. Rungs above the source are never produced: upscaling adds bytes, not detail.
Package once, describe twice. Renditions are packaged once and described by both an HLS playlist and a DASH manifest, which keeps storage single while serving every player.
Serve from the edge. Segments and manifests are distributed through a CDN; the player picks a rung and switches as bandwidth changes.

Drop the source to 480p in the Video Factory and the upper rungs close: the ladder follows the input.

Trade-offs

A fixed ladder is easier to reason about, cache and support than per-title encoding, at the cost of some efficiency on very simple or very complex content. Running moderation as a separate service, in parallel, kept a slow classifier from holding up encoding.

System

Multi-DRM protection and entitlement-gated playback

Encrypt once, license per viewer: paid creator video protected across every major DRM system, where the licence decision is a business rule about who has paid. Live in production.

DRMEntitlementHLS

System

Video moderation that fails closed

A media admission pipeline that probes cheaply, gates on spec, classifies with a model, and always returns one predictable result, rejecting what it cannot inspect.

ModerationContractsReliability

System

One upload, many episodes

A long upload can be cut into time-based episodes and announced to the platform as a series, without the creator editing anything.

EpisodesMedia processing

Adaptive streaming and the transcoding ladder

The problem

My role

How it works

Trade-offs

Related systems

Multi-DRM protection and entitlement-gated playback

Video moderation that fails closed

One upload, many episodes

The problem

My role

How it works

Trade-offs