Interlaced video can carry progressive scan signal, and deinterlacing process should consider this as well.
Typical movie material is shot on 24 frames/s film; when converting film to interlaced video using telecine, each film frame can be presented by two progressive segmented frames (PSF). This format does not require complex deinterlacing algorithm because each field contains a part of the very same progressive frame. However to match 50 field interlaced PAL/SECAM or 59.94/60 field interlaced NTSC signal, frame rate conversion should be performed using various “pulldown” techniques; most advanced TV sets can restore the original 24 frame/s signal using an inverse telecine process. Another option is to speed up 24-frame film by 4% (to 25 frames/s) for PAL/SECAM conversion; this method is still vastly used for DVDs, as well as television broadcasts (SD & HD) in the PAL markets.
Some 1080i HDV camcorders also offer PSF mode with cinema-like frame rates of 24 or 25 frame/s. The TV production can also use special film cameras which operate at 25 or 30 frame/s; such material does not need frame rate conversion for broadcasting in the intended video system format.
“Just got a C100 - first import into FCP X of the AVCHD files shows me that FCP X sees the codec as H.264 (has it converted / transcoded the AVCHD ?) – but it also still sees the files as 1080i. Is there a simple workflow solution to make the files progressive on import? I haven’t found one having searched forums.”
AVCHD is an H.264 format so FCP X hasn’t done anything to the file. Of course, you may want to tell FCP X to transcode to something more edit friendly on import. I don’t have a C100 but from memory it only records true progressive at 24p, everything else is recorded progressive segmented frame (PSF) which will show as interlaced on import. Your clip says 25fps so it’s PSF file. Even so, FCP X should play it back properly as a progressive clip, or it does when I give it PSF footage from my ATOMOS Ninja. At worst, after import select all the clips in the event library and use the info panel to set field dominance to none/progressive, or tick the deinterlace checkbox if you want FCP X to actually deinterlace the clips. You can totally depend on Pavtube MTS/M2TS Converter for Mac to achieve your goal.
How to get PSF AVCHD files to progressive?
Step 1: Import files to Mac MTS Converter. Run it as the best Mac MTS Converter, and click the “Add video” button to load your original files. You may also directly drag and drop files to application UI for importing files.
Step 2: Click the “Format” option and navigate the mouse cursor to “Final Cut Pro>>Apple ProRes 422 (*.mov)” as output format.
Step 3: Select the video and then click “Edit” button, it’ll pop up a “Video Editor” window. Move the cursor to “Effect” and tick off the “Deinterlacing”.
Step 4: When everything is ready, click “Convert” to start finishing the job.
Conclusion: After converting, you can get the generated files by clicking “Open” button. Now, you can get PSF AVCHD files to progressive.