CD Burning Problems

BurnProof & Buffer Underrun

The buffer underrun – the classic problem in CD burning. If the data flow to the recorder stalled and the recorder's buffer ran empty, the CD used to become a coaster.

What was attempted before BurnProof

Sony initially tried to make ruined CDs reusable. Then came packet-writing programs: Instead of writing many megabytes at once, they limited themselves to smaller packets the size of the buffer. It worked – but only with data CDs, and not every drive could read such discs.

Burn-Proof by Sanyo

A combination of hardware and updatable firmware. The recorder constantly monitors the buffer status. Before the buffer runs empty, it stops the writing process at an appropriate point within the EFM pattern, the buffer refills, the data is synchronized – and the writing process resumes immediately after the last point.

Today, practically every manufacturer has a similar technology – under various brand names.

Overburning

Overburning means: utilizing a blank disc's capacity beyond its specification – through the tolerance range that every blank disc inherently possesses. This is usually 2 minutes – but can vary between just under one and 5–6 minutes.

Overburning vs. Extended Length

Not to be confused with burning extended-length blanks (e.g., 80 instead of 74 minutes): In that case, the pregroove tracks are simply laid closer together. This is far less problematic than true overburning.

The actual tolerance values are constantly changing – even within the same brand, when new production series begin. So you are reliant on your own experimentation. CDRWIN can overburn, by the way. 🙂

Jitter Correction

Audio tracks have no headers with address information in the sectors – the laser cannot precisely "land" at a desired position. If the read process is interrupted and resumed, the laser has difficulty finding the point of interruption again.

The consequence: a few blocks are read twice – or some are skipped. Both cause audible crackles or dropouts in the track.

What Jitter Correction Does

The software reads a few blocks before and after the interruption and compares them with the most recently written data – this way, the exact connection point is found. Advantage: clean audio files. Disadvantage: longer read time.

Other Read Modes

• Audio Resynchronization (no jitter correction): Relies completely on the hardware. Fastest method, but requires a good drive.
• Overlapping Resynchronization: Repeats reading the last blocks and compares them. A good compromise between speed and accuracy.
• Redundant Resynchronization: Adds statistical correction patterns for highest accuracy. Can provoke buffer underruns with direct copies.

RawCopy – The Effective Copy Mode

The RAW Copy Mode is the write and read method for copy-protected CDs. "RAW" means: as 1:1 as possible, without modification. The problem: Not every drive can read raw, not every burner can write raw – and there are different RAW modes with varying efficiency.

The Historical RAW Modes

Copy Protection Methods – A Historical Overview

Today, copy protection methods on CDs/DVDs are hardly used anymore – most games rely on online license verification. But for historical purposes:

What is Legally Permitted

According to § 69d para. 2 UrhG (German Copyright Act), the buyer may create a backup copy if it is necessary for future use. However, not for copy-protected CDs. The question of "self-made or not?" is also not conclusively clarified – it depends on the license terms.

Definitely permitted:

• Copying one's own audio collection to a hard drive and creating compilations
• Copying self-purchased CDs and gifting them to family / closest friends
• Burning royalty-free / author-approved MP3s from the internet to CD

Definitely forbidden:

• Creating pirated copies, making multiple backup copies
• Patching copy-protected CDs to make them run
• Copying borrowed software CDs
• Selling copied audio CDs
• Indiscriminate copying among friends

The Historical Copy Protection Methods