Interlaving

Interlaving is a method of arranging or transmitting data, images, or events by alternating elements from different parts of a sequence. The goal is to place consecutive items at non-consecutive positions in the arranged order, often to improve resilience to errors, balance resource usage, or accommodate hardware constraints. The term derives from inter- “between” and lacing.

In video and television, interlacing refers to interlaced scanning, where a frame is split into two fields: the odd lines and the even lines, captured and displayed separately. This doubles perceived temporal resolution without increasing bandwidth. It originated with analog television and was common in standard-definition broadcasts. Modern high-definition video tends to use progressive scanning, which reduces motion artifacts.

In computing and data transmission, interleaving distributes data across multiple channels, time slots, or memory banks to mitigate burst errors or contention. Memory interleaving uses several memory modules to parallelize accesses. Data interleaving rearranges symbol order, enabling error-correcting codes to correct longer bursts. In streaming and storage, interleaving protects against data loss when some paths fail.

In textiles, interlacing describes weaving patterns where threads cross over and under each other to form fabric; interleaving, more generally, denotes the act of combining or threading elements. The term is most common for weaving, while interleaving is used more broadly in other domains.