Analogue video digitization: what happens to the signal between tape and file

What “analogue” video means

VHS, S-VHS, VHS-C, Video8 and Hi8 store the picture as a continuous magnetic signal rather than as numbers. During playback that signal is read off the tape, and every imperfection, whether stretched tape, a worn head or uneven speed, becomes a picture fault. In the analogue world, what you play the tape on really matters.

Mini DV and Digital8, by contrast, are already digital: we copy them as data, so this article applies to them only in part.

The signal path in our lab

Serviced player

A deck or camcorder with clean heads and checked mechanics. Noise from a worn head cannot be fixed afterwards.

TBC

Time base corrector. It evens out the small timing errors caused by tape stretch and removes jitter, skewed edges and “flagging” at the top or bottom of the frame.

S-Video (Y/C)

A connection that carries brightness and colour on separate wires. Compared with the yellow composite lead it gives a cleaner picture with less colour bleed.

Capture card

The device that turns the analogue signal into numbers at full PAL resolution (720 × 576). Cheap USB grabbers often drop frames and drift the sound.

Check

We review the recording, confirm that sound matches picture and trim the blank tail of the tape.

Interlacing: why old video looks “combed” on a new screen

Analogue TV drew each picture in halves: first all the odd lines, then all the even ones, 50 times a second. This is called interlacing. On an old CRT you never noticed, but on a modern screen moving objects show a comb effect, with jagged edges.

So when we create the MP4 we deinterlace the picture properly, giving smooth motion and clean edges. If you want the original interlaced file for editing, mention it in your request.

What we deliberately do not do

We do not invent detail that is not in the recording, and we do not alter the original content. Our job is to get everything that has survived on the tape and hand it to you in a dependable file. If a tape is damaged, we repair or clean it first (€9 per tape), because only then is the start of the chain good enough.

And cine film?

8 mm and Super 8 film is not magnetic: it is a strip of tiny photographs, digitized frame by frame with a scanner or camera. That service costs €2.90 per minute; see the price list.

What it costs

All analogue tapes are priced per cassette: VHS €15; VHS-C, S-VHS, Video8 and Hi8 €9. Running time does not change the price. Ship the tapes by Omniva, SmartPosti or DPD parcel locker to Tallinn, and pay by invoice after the work, as a private person or a company.