Errors extracting video from MakeMKV DVD rips

[paulster]

I've got a number of NTSC DVDs which are actually 480p with pulldown flags so they display at 60Hz even though they are actually encoded on the DVD itself at 24fps (/1.001).

Since I can playback 480p/24 material I figured I'd extract the video files and remove the pulldown flags, exactly as I've had to do with the few HD-DVDs I have.

Pretty much every DVD file I've fired eac3to at has given me the message 'The format of the source file could not be detected.' when I try to catalogue the tracks before choosing the video track to export, and the few that have worked have given me errors like 'v01 Video has a gap of 7 frames at playtime 0:04:42.'

Anyone have any thoughts on what's going on and how best to remove the pulldown to get a genuine 480p/24 file without re-encoding?

[BlackDragon24]

I've got a number of NTSC DVDs which are actually 480p with pulldown flags so they display at 60Hz even though they are actually encoded on the DVD itself at 24fps (/1.001).

Since I can playback 480p/24 material I figured I'd extract the video files and remove the pulldown flags, exactly as I've had to do with the few HD-DVDs I have.

Pretty much every DVD file I've fired eac3to at has given me the message 'The format of the source file could not be detected.' when I try to catalogue the tracks before choosing the video track to export, and the few that have worked have given me errors like 'v01 Video has a gap of 7 frames at playtime 0:04:42.'

Anyone have any thoughts on what's going on and how best to remove the pulldown to get a genuine 480p/24 file without re-encoding?

I don't think this is possible to do. The only way to convert NTSC encoded DVD's (29.970 fps) to 24p (23.976 fps) is to IVTC or Tdecimate them and both of those functions require re-encoding. Have you analyzed the video frame by frame to confirm it is indeed 24p and does not contain hard-coded duplicate frames and or telecined content?

[paulster]

I don't think this is possible to do. The only way to convert NTSC encoded DVD's (29.970 fps) to 24p (23.976 fps) is to IVTC or Tdecimate them and both of those functions require re-encoding. Have you analyzed the video frame by frame to confirm it is indeed 24p and does not contain hard-coded duplicate frames and or telecined content?

NTSC DVDs can actually be encoded in 24p or 60i framerates and for 24p there are pulldown flags to tell the player which fields to duplicate to generate 60i output. Removal of the pulldown from a genuine 24p source doesn't require re-encoding (since the mpeg encoding is done on the 24p source and then the flags are put in the file), whereas those files which have had the pulldown burned-in, so to speak (i.e. applied prior to mpeg encoding), and have a 60i-encoded stream on the disc would require re-encoding.

The difference in the process is as follows:
24p -> mpeg encode -> add pulldown flags -> 60i
24p -> apply pulldown to source -> mpeg encode -> 60i

You'll see that in the first instance if you remove the pulldown flags you are left with an mpeg-encoded 24p stream, which won't have the jerkiness on panning that pulldown creates.

If you take a look at a few MKVs created from NTSC DVDs with eac3to you'll see that some list the content as 60i and some as 24p. I'm only interested in the ones with genuine 24p content and getting them into 24p MKVs so I can at least make the most of the original source material without introducing any further losses by re-encoding.

The problem seems to be that eac3to doesn't like a lot of DVD MKVs created with MakeMKV and seems to find errors in those that it will actually process.

[crowfax]

I'm pretty sure you can do what you want with DVD Patcher. Just create the MKV as normal, then extract the MPEG stream using MKVextract, then open it in DVD Patcher and save the stream as 23.94fps. Once you have the newly saved MPEG stream you need to remux the newly saved stream back into the MKV using mmg, unticking the old MPEG stream and putting the new one in its place.

[paulster]

Cool, thanks. I'll give that a try.

[BlackDragon24]

Cool, thanks. I'll give that a try.

If you are able to accomplish this, please report back .

[paulster]

DVDPatcher didn't work. The file afterwards still showed as '24p with pulldown flags' so the MKV played at a 60Hz refresh rather than 24Hz.

[BlackDragon24]

DVDPatcher didn't work. The file afterwards still showed as '24p with pulldown flags' so the MKV played at a 60Hz refresh rather than 24Hz.

Bummer. Thanks for reporting back.

[crowfax]

Sorry to hear that. I'm out of ideas.

[setarip_old]

@paulster

Hi!

You might want to look into "PGCEdit" at:

http://download.videohelp.com/r0lZ/pgcedit/

[paulster]

Thanks for the suggestion; I'll give that a look.

It probably won't be for a little while as I've got a mountain of stuff to go through first but I'll post my findings here as soon as I've had the chance to try this.