2:3 pulldown & inverse telecine

Four pictures, five video frames.

Conventional 2:3 pulldown, also called 3:2 pulldown, represents a progressive picture sequence in an interlaced video signal. Alternating source pictures contribute two or three fields. Four source pictures become ten fields, grouped into five video frames. Some video frames therefore contain fields from different source pictures.

For the fractional-rate workflow here, the source is 24000/1001 pictures per second, usually called 23.976 or 23.98. The output is 30000/1001 interlaced frames per second, usually called 29.97, with 60000/1001 fields per second. “59.94i” commonly counts fields; it does not mean 59.94 complete frames per second.

Read one complete cadence.

Label four source pictures A, B, C and D. One illustrative phase distributes them in temporal field order as A A B B B C C D D D. Pairing consecutive fields produces AA BB BC CD DD.

“Earlier” and “later” describe time, not upper or lower raster fields. Confirm the actual field order and cadence phase before interpreting a file. A clip can begin elsewhere in this cycle; do not apply the table’s starting phase universally. Adobe’s fields and pulldown reference explains why both phase and field order matter.

The duration agrees on both sides:

For a longer example, 1,440 progressive pictures at 24000/1001 last 60.060 seconds. A complete 2:3 transfer contains 1440 × 5/4 = 1800 interlaced frames at 30000/1001, also 60.060 seconds. The 360 additional video frames do not represent 360 newly photographed moments.

Those same 1,440 pictures at integer 24 fps last 60.000 seconds. The 0.060-second difference belongs to the prior rate conform, not to the field cadence. Keep sound treatment and any speed change documented separately.

Recover pictures before choosing a new rate.

Inverse telecine, or reverse telecine, identifies the repeated-field pattern and reconstructs the underlying progressive pictures. In the example, the intended result is A, B, C, D at 24000/1001, retaining the telecined programme’s elapsed duration.

Generic deinterlacing addresses interlaced fields without necessarily recovering that original sequence. A clean-looking still frame alone does not establish successful cadence removal. Check movement frame by frame, the resulting picture count, scan type and playback rate. Do not simply discard every fifth video frame: this phase includes mixed-picture frames that need proper field reconstruction.

Choose the operation in the media tool after identifying the source. Apple documents reverse telecine in Compressor. Final Cut Pro’s documented Remove Pulldown import option has a specific tape-camera/device limitation; a similarly named feature is not a promise that every file-import path supports it.

Progressive sources need a source check.

A native 23.976 or 24 fps progressive recording may contain no pulldown to remove. A progressive scan or image sequence also does not become telecined merely because it came from film. Start with acquisition records and actual pictures, rather than inferring a cadence from a cinema-rate label.

For a modern progressive master, agree the destination rate and whether to preserve duration or source frames. Adding interlaced pulldown is appropriate only when the receiving workflow calls for it. See film to digital for scan and conform decisions, and frame-rate conversion for mixed-rate delivery.

Inspect the joins and the processing history.

Editing telecined material can break its cadence at cuts. Apple’s Compressor guide describes this distinction between continuous and broken cadence. Review joins, dissolves, titles and mixed-source sections in the processed result; a successful test on one uninterrupted shot does not validate a complete programme.

1. Retain the original and record its exact rate, field order and any known transfer history.
2. Test a moving section and a cut before processing the complete asset.
3. Check whether ingest or an earlier transcode already removed pulldown. Repeating removal can damage a correct progressive sequence.
4. Verify the recovered count and duration against a complete-cadence example, allowing for partial cycles at clip boundaries.
5. Check audio sync and preserve the relationship between source identifiers and the new progressive sequence.

Drop-frame timecode changes numbering, not this picture pattern. Selecting DF cannot add, remove or repair pulldown. The drop-frame guide explains that separate counting decision.

Use the arithmetic to check a handoff.

Use Timecode Pro for timecode, frame-count and footage arithmetic around the job. Keep the exact source rate and the assumed 4:5 relationship beside your calculation. Its format conversions follow the app’s presets; the physical-duration equations above state their own assumptions.

Timecode Pro does not inspect fields, remove pulldown or process media. Perform those operations and picture checks in the appropriate media application. A useful turnover includes both the calculation and the verified media properties.