Rendered Video Plays Choppy

[Weeination]

I have two MP4 files which I am joining together. The first is 5.6 GB and I am using all of the video (except for the first few seconds) from a transfer of an old one-hour Betamax recording. The second is 5.3 GB and I am using half of the video from that transfer of another one-hour Betamax recording. Basically, I am joining up the two parts of the same recording into one file. I am trying to keep the new video file to within 4 to 5 GB in size.

Near the latter part of the new video file, I noticed that it didn’t play smoothly. Movement seems choppy. Also, when I click over to that part of the video file it freezes up. The source file from the transfer does not play that way.

I created the new video file with the setting MPEG-4 AVC (720 x 480, 30p, 2.5 Mbps). That video file is 2.5 GB.

Is there a custom profile anyone can recommend to avoid the issues I am seeing with the new video file?

The properties of both files created from the transfers of the two Betamax tapes are

H.264 Main Profile Video
24 bits, 720 x 480
60,000 frames/sec
3474 kbps

MPEG AAC Audio
48000 Hz. 16 Bit, Stereo
1 Kbps

Is it advisable to lower the high frame rate? What would be the drawback in doing so?

[lata]

The details of your video look a little unusual, 60,000fps, is that a typo for 60i.
If you right click the video on the timeline and choose properties, what are they?
You could create an image of that panel to attach to your post.
Your project properties should also match the video properties, can you check that.

When you render, Share – Same as first video clip.
Option top left, tick the box to activate then change option.
This will use the same properties as your video,

[Ken Berry]

Another thought I had was the Field Order: are the videos using Upper Field First when, being old, they might originally have been Lower Field First. But then again, since the choppy playback only affects a part of the rendered video, I can't think how this might have occurred unless the first video uses the correct field order but the second has a different field order...

As for the 60,000 I suspect this might have come from Properties given in another European language. We in the English-speaking countries would normally write 60.00 (though that would be unusual with reference to frame rates). However, in another European language our zero becomes a comma and three zeros are used for our two... Just a thought...

[Weeination]

Sorry guys, that’s a typo. The frame rate is actually 60.000 frames/sec

I am editing several of these transfers of old recordings ranging from the late 60s to the early 70s.
In project properties I have the video data rate set at 4000 kbps which is the maximum allowed for Mobile. I did that because the data rate for these transfers as shown in properties are different for each. For example, one is 13972 kbps, another is 3215 and two others are 1418 and 844. I noticed for the one with the lowest data rate it affected video quality of the rendered file when using 844 kbps. Therefore, I stopped matching the project properties with the video file properties.

However, when Ken mentioned then field order, I noticed for at least one of these videos I am editing that the field order is frame based. They probably all are. In my project properties I didn’t change the field order. Is the default setting Upper Field First? Whatever the default setting is that is probably what I used. If I did use a different frame type in project properties than what are the properties in the source videos then would that affect playback of the rendered files in any way? I didn’t notice any problems on playback for all of the other rendered files created from those source videos. The only difference with this latest attempt at creating a new video file after editing is because I am trying to keep it at around 4 GB.

I rendered a video file with same as first clip. Then I jumped ahead to the second half of that video with VLC. It freezes up.

[Ken Berry]

If the whole thing is Frame Based, that would be a good thing, and if the project properties are also set to produce a frame based video, that too would good. Frame based essentially means that a video is made up of a succession of whole frames. Upper or Lower Field First videos, on the other hand, are made up of a succession of partial frames, with UFF ones -- as the name suggestions -- starting with a partial image consisting of the first, third, fifth, seventh etc lines coming first and followed by another partial image containing the second, fourth, sixth, eighth etc lines. LFF, as its name suggests, would start with the second, fourth etc and followed by the first, third etc.

If a video is made using LFF, but is then processed with UFF, the lines would be confused and the video would be choppy. Same if it was originally UFF but processed as LFF. So that's the reason why its important to make sure you haven't got UFF video mixed with LFF and with rendering set to produce one or the other. But fine if set to produce Frame Based since any UFF or LFF video will be converted to whole frames, thus avoiding any problem.