Visual Cinema Masterclass · Module 5 of 6

Post Production and Delivery

Every step after the shoot is a trade, and most of them are irreversible

Post production is a sequence of compromises about quality, size, time and compatibility. This module sets out the trades in the order they arrive, and marks the ones you cannot undo.

Quality against size, and why codecs come in pairs

A codec decides how picture data is compressed. A container decides how the compressed streams are stored together with sound and timing. The two are routinely confused because the container name is what appears in the filename, and it tells you almost nothing about what is inside.

The important split is between codecs designed for editing and codecs designed for delivery. An editing codec compresses each frame on its own, so any frame can be decoded without reference to its neighbours. That makes scrubbing and cutting responsive at the cost of large files. A delivery codec stores occasional complete frames and then describes the differences, which is dramatically more efficient and much harder to work with, because reaching one frame means decoding others first.

The trade is irreversible in one direction. Transcoding from a delivery codec into an editing codec produces large files that do not recover the detail already discarded. Deciding this at ingest rather than halfway through is the whole discipline.

Convenience against fidelity, and the proxy question

Proxies solve a real problem by editing against small lightweight copies and relinking to the originals before finishing. The risk is procedural rather than technical. A relink that silently fails, or a grade applied to the proxy rather than the original, produces a final master that looks worse than the rushes.

The check is dull and worth doing: confirm before delivery that the timeline is actually referencing the camera originals, and that the resolution and colour of the output match what was intended rather than what the proxy carried.

Speed against control in compositing

Keying is where the earlier decisions come due. Pulling a clean edge from green screen depends far more on how the subject was lit and separated from the backing, and on how much colour information the codec kept, than on the sophistication of the software.

This is where chroma subsampling stops being an abstraction. Colour recorded at reduced resolution gives the keyer less to work with exactly at the edges where it matters, producing the stepped or fringed edge that then has to be hidden. No amount of adjustment recovers information that was never recorded, which is why the decision about acquisition format is really a decision about how much compositing will cost.

Legibility against elegance in titles

Motion graphics and titling carry a constraint that the rest of post does not: the result has to be readable at a glance, often by someone not paying full attention, sometimes on a small screen. Contrast against a moving background, time on screen relative to the number of words, and safe margins all matter more than the typography.

Text that a designer can read on a large calibrated monitor while stepping through frames is not evidence that a viewer can read it at speed. Checking at final size and full rate is the only test that counts.

Now against later, and the version that survives

The last trade is the one nobody is paid to make. A finished job leaves behind camera originals, a project file, a set of masters and a large amount of intermediate material, and the decision about what to keep is usually made by whoever needs the drive space back.

What matters later is rarely the intermediate work. It is the camera originals, the final project in a form that can be opened, the graded master in the highest quality version made, and a plain text note saying what the delivery specification was and which colour space the master sits in. That note costs ten minutes and is the difference between a straightforward revision in two years and an expensive reconstruction.

Versioning is the related discipline. A master named final is a master that will be superseded, and the second most common delivery failure after specification mismatch is sending the wrong cut. Dates in filenames are unglamorous and they work.

Loudness, which is a delivery constraint and not a taste

Audio delivery is specified as precisely as picture and is more often got wrong, because a mix that sounds right in the room can still fail an automated check. Broadcast and streaming platforms specify an integrated loudness target and a true peak ceiling, and a file outside those limits is either rejected or normalised by the platform in ways the mixer did not choose.

Mixing to the target from the start is easier than fixing it afterwards, because loudness correction applied late tends to squeeze the dynamic range the mix was built around.

Universality against specificity in delivery

A delivery specification exists so that a file plays correctly on equipment its maker never saw. It constrains codec, resolution, frame rate, colour, audio layout and loudness, and the constraints are usually not negotiable. Cinema packaging is the strictest example, with a defined structure and its own colour encoding, and it is unforgiving of anything approximate.

The failure here is almost never creative. It is a mismatch between what was graded and what was asked for, discovered at the point of handover when there is least time to fix it. Reading the specification at the start rather than the end is the cheapest possible insurance.

Vocabulary

Intraframe codec: Compresses each frame independently. Large files, responsive editing, and the format most post production actually wants.
Interframe codec: Stores occasional full frames and describes the differences between them. Efficient for delivery, awkward for editing.
Container: The wrapper holding compressed video, audio and timing together. Its name tells you little about the codec inside.
Proxy: A small stand in copy used for editing, relinked to the original before finishing. The risk is procedural, not technical.
Delivery specification: The set of constraints a finished file must satisfy to be accepted. Usually fixed, and best read before the grade rather than after.

Where the detail lives

This module carries the through line. The step by step work is in these guides.

Sources and confidence

Delivery specifications are published by the broadcaster, distributor or standards body concerned and change over time. Always work from the current specification supplied for the job rather than a remembered one.

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