telecined

Telecine is the process of converting film, typically shot at 24 frames per second, into video by applying a cadence that matches the target video frame rate. The term can refer to the process itself, the equipment used, or the resulting video. Telecine is commonly used to make film content compatible with broadcast or consumer video formats.

In practice, the most widely seen form is converting 24 fps film to the standard video rate used in NTSC systems, about 29.97 frames per second, through a method known as 3:2 pulldown. This pattern repeats film frames across multiple video frames to preserve motion continuity. For PAL regions, 24 fps film can be transferred by speeding up to 25 fps or by alternative mapping methods. The result often involves interlaced video, where each frame is composed of two fields.

Telecine is distinct from inverse telecine, the process used to recover the original 24 fps (or 23.976 fps) sequence from telecined video. This reversal is common in modern digital workflows where archival or post-production work requires frame-accurate access to the original film content.

Applications of telecine include broadcast distribution, on-air video production, and physical media transfers where real-time conversion was advantageous. With the rise of digital distribution and native 24p/23.976 workflows, the reliance on telecine has diminished in some contexts, but it remains a part of legacy pipelines and certain formats.

Limitations of telecine include the introduction of a consistent cadence that can complicate editing, improper deinterlacing, and potential motion artifacts if the source or playback conditions are inconsistent. Understanding telecine is important for workflows involving film-to-video conversion and for managing downstream processing such as IVTC and deinterlacing.