Is it possible to convert a 60fps DTV stream to 30fps for DVD authoring?

[Xoanon]

I recently got a DVR and did a few test recordings. On an HD channel, a 720p broadcast was playing. I captured a few minutes of the .MTS stream and demuxed it with ProjectX onto my PC. I assumed it would be 30fps but it is actually 60fps.

If I wanted to capture a program on TV and convert it to DVD (downscaling the picture to SD aside), what is the best way to reduce the frame rate to 30fps for the DVD standard? Surely reducing the frame rate would cause sync issues with the audio stream?

[pandy]

Generally yes but perhaps it is already DVD compliant (60 fps can be outcome of deinterlacing) - if this is true 60fps then i would suggest to interlace.

[Xoanon]

EDIT: Apologies, I get it now

[usually_quiet]

I recently got a DVR and did a few test recordings. On an HD channel, a 720p broadcast was playing. I captured a few minutes of the .MTS stream and demuxed it with ProjectX onto my PC. I assumed it would be 30fps but it is actually 60fps.

If I wanted to capture a program on TV and convert it to DVD (downscaling the picture to SD aside), what is the best way to reduce the frame rate to 30fps for the DVD standard? Surely reducing the frame rate would cause sync issues with the audio stream?

There are a couple of ways to do it. Normally the video would be resized to 720x480 and interlaced using 29.97 fps with 16:9 display aspect ratio to preserve the temporal resolution. It is the best way to go in situations where each frame is unique. I have used AVStoDVD to do this.

TV shows that are shot on film could be frame decimated to 24 fps (discarding repeated frames) and re-sized to 720x480, to be used for 16:9 DVD video at 23.976 fps with 3:2 pulldown. (The DVD video is progressive, encoded as interlaced.) I have never tried this.

[Xoanon]

Generally yes but perhaps it is already DVD compliant (60 fps can be outcome of deinterlacing) - if this is true 60fps then i would suggest to interlace.

If I interlace it with VirtualDub, do I choose odd or even field first in the options? And do you recommend leaving it interlaced before encoding to MPEG-2 for DVD authoring?

[manono]

And do you recommend leaving it interlaced before encoding to MPEG-2 for DVD authoring?

If it's film-based and 23.976fps originally, then you'd want to remove the duplicate frames to get it back to 23.976 again before encoding as progressive with 3:2 pulldown. You seemed to ignore half of usually_quiet's helpful reply. If you don't know what you have then make available a 10-second portion, one with steady movement.

If it's from an interlaced source then, yes you might want to reinterlace it before encoding.

[pandy]

Generally yes but perhaps it is already DVD compliant (60 fps can be outcome of deinterlacing) - if this is true 60fps then i would suggest to interlace.

If I interlace it with VirtualDub, do I choose odd or even field first in the options? And do you recommend leaving it interlaced before encoding to MPEG-2 for DVD authoring?

My fault - overlooked 720p info - follow usually quiet advise (check if source is progressive and less than 60fps for example cinema movie can be 24 fps), interlacing can be done in multiple ways - for example i use Avisynth or ffmpeg - both working fine - this is purely up to personal preferences.

Field should be correct and consistent i.e. if video is BFF then codec should be configured as BFF - generally US area is BFF where Europe is TFF.

Audio should be in sync if video length stays same as before conversion.

[Xoanon]

Thank you very much

[theewizard]

i run the mts video thru video redo, do a quick fix, edit out the commercials, save as mpeg2, at the captured 59.xx fps

then load that file into avstodvd, and create the DVD

i did this for NBC's live Sound of music broadcast
and again for the recent broadcast of "Jurassic Park", done before the release of the new Jurassic World movie

[Xoanon]

VideoRedo allows frame by frame cutting, not just I-frames?

[KarMa]

In the US on 720p HD channels, the only thing that is truly 60fps (59.94) are sports and maybe the nightly news broadcast. For most other things they just duplicate frames to fit a 29.97fps or 23.976fps program on 59.94fps broadcasts.

VideoRedo allows frame by frame cutting, not just I-frames?

Yes but it will re-encode parts or all of the GOP that you are cutting into.

[Xoanon]

Yes but it will re-encode parts or all of the GOP that you are cutting into.

Thanks for that. Is there noticeable quality loss? And can you cut the AC3 audio stream at the same time and demux this edited stream without reencoding?

[KarMa]

Yes but it will re-encode parts or all of the GOP that you are cutting into.

Thanks for that. Is there noticeable quality loss? And can you cut the AC3 audio stream at the same time and demux this edited stream without reencoding?

There is a small loss but nothing horrible. I even use it to cut up H.264 broadcasts, which it re-encodes a few frames of the GOP. It's not always perfect with cutting H.264, considering how complicated the GOPs can get but with MPEG2 broadcasts, Videoredo does great. It will cut and resync the AC3 audio along the cuts too.

[Xoanon]

I might see if I can get this, then. Thanks again.