CineForm Inverse Telecine

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Inverse Telecine

Inverse Telecine Processing - Sony HVR-V1U, Canon HV20, and Other HD Camcorders
Want to see camera-specific HDLink capture settings? See our Tech Note HDLink Capture Settings Tech Note. Want to see HDLink file-conversion settings? See our Tech Note HDLink File Conversion Techniques Many HD camcorders - such as Sony's HVR-V1U and Canon's HV20 - now offer the ability to record 24p (24-frame progressive) to emulate the visual "feel" of film recording. But before it is recorded to HDV tape, 24p material captured by the image sensor is often inserted into an interlaced 60i (60 fields per second) HDV stream - a process called "telecine". Background To maintain the visual benefits of 24p through post production, it is necessary to extract the original 24p signal from its encapsulation in 60i. This is done using a technique called "inverse telecine" or "pulldown removal". After inverse telecine processing the resulting file is again 24p (23.976), and is now ready for a 24p editing workflow. Depending on many parameters, removing telecine is not always straightforward, so many capture applications and non-linear editors do not include the feature. All CineForm products provide inverse telecine processing in the HDLink utility. In addition, Aspect HD and Prospect HD/2K include inverse telecine processing using the Premiere Pro capture interface. For improved visual fidelity, also consider this: All CineForm products offer real-time inverse telecine processing when capturing live 24p material (embedded in 60i) through an HDMI interface as included on Sony's HVR-V1U and Canon's HV20. In this mode, the 60i signal output by the camcorder (through HDMI) is prior to MPEG compression. When HDMI sources are captured direct-to-disk into CineForm Intermediate with "inverse telecine" selected, the resulting files have much higher visual fidelity than those recorded to HDV tape. This is because CineForm Intermediate offers lighter compression, twice the chroma fidelity, and higher bit-depth precision than MPEG recording. This visual fidelity benefit is especially important for projects in which substantial post processing (keying, compositing, color correction, etc) is being applied. See our HDMI Tech Note for more details. NOTE: HDMI recording requires use of the Blackmagic Intensity card.
To Extract 24p Using HDLink:
In the HDLink Prefs window (above), select the Frame Rate Change option that says "Remove 3-2 Pulldown". Then click 'OK' and begin capturing (or converting your files if already on disk).
To Extract 24p Using Premiere Pro (via Firewire)
Make sure your camera is plugged in, turned on, and set to VCR mode. Then load the Capture Window (F5) to see the screen below and go to the Settings Tab. Make sure that CineForm HDV Device Control is selected in the Device Control drop-down list. In the Capture Settings dialog, click on the 'Edit...' button.

From the Project settings dialog box, click on the 'CineForm HDV Settings...' button as shown below. (If you can't see that button, then your camera is not connected properly).

From the CineForm HDV Capture Settings window, select the Frame Rate Change option to "Remove 3-2 pulldown" as shown. Then Click 'OK' to close the CineForm HDV Capture Settings window and then click 'OK' again to close the Project Settings window. Then capture your footage into a 23.976 project.