Bitrate

What this is about

Bitrate is where storage budgets are decided. Multiply the recording rate by the shooting hours and the card and drive plan writes itself. Below a certain rate, compression starts throwing away detail the eye notices first in movement, grain and gradients — water, foliage and smoke break down long before a static interview does. Constant bitrate keeps the number steady and is predictable for broadcast; variable bitrate spends more on complex shots and less on simple ones. Recording higher than the delivery target is normal, because every further encode costs quality.

A term only helps when everyone on set means the same thing by it — so what follows is how it is used, not a dictionary definition.

What runs differently here

In planning terms, that means:

• Bitrate times running time equals storage — the fastest way to size cards, drives and backups
• Movement, grain and gradients collapse first when the rate is too low; a static talking head hides it
• Always record above the delivery bitrate, because every re-encode subtracts quality

With TillyGen

With shooting days and formats in the plan, TillyGen makes the data volume of a project visible before anyone stands on set with too few cards.

Change one constraint and the consequences travel through the whole plan: affected shots are flagged, the call sheet is regenerated, and nobody keeps working from yesterday's version.