HD 23.97P to 50i?

[FrameConverter]

Similar to my other post (25P to 59.94i which I now have working btw, thanks) I would now like to go from 23.97 to 50i. Can someone suggest a good script to make a smooth cadence? Keep in mind I do not want to make any speed changes so my audio will match. The source footage is progressive 23.976fps HD (1920x1080) and I am looking for a 1920x1080 interlaced 50i result.

Thanks!
FC

[scharfis_brain]

encode as progressive 23.976p and set field repetition flags.

[FrameConverter]

No, this is not for DVD playback, I am looking to actually create new fields with the duplicated material. This has to be output back to an HDCAM tape for 50i playback.

Thanks, any other ideas?

FC

[IanB]

AssumeFPS(24000, 1001) # Reset rational values exactly!
ChangeFPS(50, 1) # Make it 50fps repeated Frame
SeparateFields()
SelectEvery(4, 0, 3) # BFF or (4, 1, 2) # TFF
Weave()This will use exactly 480 input frames per 1001 output fields.

As with setting field repetition flags, there will be a 1 field jitter every 12 to 13 frames i.e.
0 0 1 ... 11 12 12 12 13 ... 22 23 23 23 24 ... This ~2Hz jitter may be quite noticable for some pragram material.

Using ConvertFPS() instead will use field level blending :devil: of input frames which may be more visually acceptable than the jitter.

The choice is somewhat material dependant. Are you sure you would not rather just reclock the audio and video +4% to 25fps and interlace from there.

[scharfis_brain]

@Ianb:

SeparateFields()
SelectEvery(4, 0, 3) # or (4, 1, 2) TFF/BFF
Weave()

needs to be:

Assumetff(0 #or Assumebff()
SeparateFields()
SelectEvery(4, 0, 3)
Weave()

because 4,1,2 and previouslt assumed TFF will result in BFF.

[FrameConverter]

...Are you sure you would not rather just reclock the audio and video +4% to 25fps and interlace from there.
Definately. This is for broadcast material and the running length has to be the same.

Thanks for the code, I havent had a chance to try it yet.
FC

[Mug Funky]

if it's for broadcast, field-blending is probably fine, so if the jitter bothers you give convertfps a try :). however, blended fields hurt compression quite badly in motion scenes. this is probably an issue for broadcast HD, as there most probably will not be enough data rate to absorb that, and it could easily look fine on the tape but crap when broadcast.

mvflowfps is _not quite_ ready for public consumption yet.

it's performing somewhere between the cheaper motion-compensated converters and motionperfect/twixtor. artefact protection is the last hurdle for it to overcome in my opinion. it's nearly there (when it is i think it'll be showing up in some r4 DVD extras to see if anyone notices :)).