352x240 23.976fps Problem

[Xesdeeni]

I'm trying to burn some 352x240 @ 23.976fps MPEG-2 videos created with CCE onto a DVD. The videos (and audio) seem fine on the PC, but I'm having problems in my actual DVD player.

DVD Maestro wouldn't let me use the videos until I ran pulldown.exe on them, which makes sense. But I'm not sure this works the same for 352x240 as 720/352x480.

When I view the video that resulted after running pulldown.exe with the defaults on the PC, it bobs up and down. So I tried setting the -tff flag to ODD on one run and EVEN on another.

Then I went to author them with DVD Maestro. The program accepted them OK, but the frames were all white on the timeline (using the chapter selector) in all three cases.

When I viewed the burned DVD on my stand-alone DVD player, the first video (default) one was really screwed up. It was only on the left half of the screen and alternated between white and a vertically stretched version of the video. I couldn't see any difference between the second and third videos, but they both played back too fast, outrunning the audio track.

Anything obvious that I did wrong?

Xesdeeni

[j1d10t]

My first thought would be that for that resolution, 352x240, you needed to make the file MPEG1, not MPEG2. For DVD format, that resolution needs to be MPEG1, unless you are making a non-standard DVD. And since the file would then be encoded in MPEG1, you shouldn't need to run pulldown on the file, your DVD player should do the pulldown for you.
Just a thought...

[Xesdeeni]

According to http://www.dvddemystified.com/dvdfaq.html#3.4, 352x240 in MPEG-2 is legal. I would have just used MPEG-1, but I was under the impression that there were a few quality advantages to MPEG-2. Plus, I didn't know if MPEG-1 supported anamorphic video, which these videos are.

Xesdeeni

[j1d10t]

I was going by what it says on this site, over on the left...

Quote from https://www.videohelp.com/dvd
"Video:
Up to 9.8 Mbit/sec MPEG2 or up to 1.856 MBit/sec MPEG1 video
720 x 480 pixels MPEG2
704 x 480 pixels MPEG2
352 x 480 pixels MPEG2 (Same as the CVD Standard)
352 x 240 pixels MPEG1 (Same as the VCD Standard)
29,97 frames/second
24 frames/second with 3:2 pulldown (NTSC Film, this is only supported by MPEG2 video)"

And I think you are right, that MPEG1 doesn't support annmorphic video.

[adam]

Until very recently DVD Demystified specificallys said that 352x240/288 was only valid in the DVD standard when using mpeg1. It was changed when the faq was last updated, and I think this is probably the definitive source for DVD specification, at least as far as what us non-industry folk have access to. So it seems that 352x240 mpeg2 is perfectly valid.

However, if you keep reading that faq you will see that anamorphic encoding is NOT supported in 352x480/576 or 352x240/288 regardless of whether you are using mpeg1 or mpeg2.

Xesdeeni, this is most likely the cause of your problem, and the fact that only presents itself on your hardware player probably confirms this.

[j1d10t]

Very interesting. Thanks for clearing that up Adam. Do you know if there are any plans to up-date the DVD specs here?

[Xesdeeni]

However, if you keep reading that faq you will see that anamorphic encoding is NOT supported in 352x480/576 or 352x240/288 regardless of whether you are using mpeg1 or mpeg2.

Section 3.5 (http://www.dvddemystified.com/dvdfaq.html#3.5) implies that 352x480 can be used for anamorphic in the table near the bottom. I don't see anywhere that indicates that 352x480/240 cannot be used. Where do you see this?

Also, the playback of the 352x240 video, once I've done pulldown (with either -tff EVEN or -tff ODD) is too fast, but the image is not screwed up. The scaling is done correctly. Also, I'm pretty sure that several DVD extras of outtakes done at 352x240 (presumably to save space) that I've seen were anamorphic.

Xesdeeni

[pijetro]

I also have played with changing the Tff and Rff flags, but it never worked for me. I found when field orders needed to be changed, Restream was the best. I simply unchecked the current field and saved. Very simple and always worked (it needs to be in it's elementary stream, not .mpg though)....As far as Pulldown.exe is concerned, all the options were unchecked ready to go....

It seems an oddball resolution for DVD (although legal). Perhaps the Maestro doesn't support that resolution properly??
Just a thought.......

[adam]

Sorry, I could have sworn it was in DVD Demystified, but I was thinking of mpeg.org's site instead... http://www.mpeg.org/MPEG/DVD/Book_B/Video.html

Under supported aspect ratio's it says, "16:9 (all formats except 352 pixels/line)" So this includes both 352x480/576 and 352x240/288.

As far as the chart on DVD Demystified, I agree its misleading. I think he was just trying to show the ratio you get with 16:9 and he needed more than just 2 examples, ie: 720x480 + 704x480.

I'm quite certain that 16:9 is not supported in 352 pixel/line resolutions, so if you saw any such DVDs than its not out of the question that they were just authored incorrectly, it happens more often than you would think. But what DVDs were they if they used 352x240 resolution even on extras? I have never heard of a commercial DVD using anything other than 720x480/576 or in very very rare instances, 352x480/576. The support for 352x240 resolutions was really only included in the DVD standard to make it more supportive of VCDs, so that one could easily transfer a VCD to DVD without having to re-encode the video. This resolution is just not suitable for commercial releases when higher resolutions are supported, and especially not for DVD extra's which are almost always interlaced because this resolution doesn't even support interlacing.

@j1d10t, I'll bring it to Baldrick's attention regarding the support for 1/4th D1 res and mpeg2 in the DVD standard and see if he wants to update this site to match DVD Demystified.

[Xesdeeni]

Actually several DVDs we've rented had extras at 352x240. Mostly deleted scenes. I can't recall the specific ones, but the video looked horrid (I could tell you some of the DVDs we rented, but I can't recall which ones had deleted scenes that looked horrible). Now that I think of it, I can't be absolutely certain the extras weren't encoded at 4:3 with letterboxing, since I didn't actually rip them.

The strange thing is that the video plays back OK as far as the picture, it's just too fast. Maybe I should set the frame rate to 23.976? But then I think Maestro would refuse them.

Xesdeeni

[adam]

If you encode at 23.976fps with mpeg2, then you must have 3:2 pulldown flags in the stream in order to comply with the spec, and in most cases in order to get proper playback on a hardware dvd player. I can't see how the addition of the pulldown flags could be causing the video to speed up. You may have some strange problem in your process somewhere that is causing your problem, but in any case, its always a good idea to ensure what you are doing is compliant first before trying to problem solve other issues, so make sure you are only using 4:3 with these resolutions.

Well, since the resolution does comply to DVD spec its obviously possible for commercial DVDs to use a resolution of 352x240 but I honestly just find it very hard to believe you would find such a DVD, especially multiple times. I've ripped at least 1000 separate DVDs over the years and I have never seen such resolutions used for anything on a mainstream DVD release, ie: something you'd find in a rental store. I'm curious though, how did you know what the resolution was of these DVDs if you didn't rip them?

[Xesdeeni]

If you encode at 23.976fps with mpeg2, then you must have 3:2 pulldown flags in the stream in order to comply with the spec, and in most cases in order to get proper playback on a hardware dvd player.

That was my understanding, although the one time I tried to use pulldown.exe on a 720x480@23.976fps video created with CCE, I didn't get proper video playback. The video appeared to repeat the wrong fields. The same video encoded with TMPGEnc with "3:2 pulldown on playback" selected played perfectly. In fact, the latter would show all 480 lines when paused on my stand-alone DVD player, while the former would show a single 240-line field replicated when paused.

I can't see how the addition of the pulldown flags could be causing the video to speed up.

My theory was that the flags were somehow being missed, perhaps due to the 352x240 video format, so the video was actually playback back at 29.97fps, but without replicating fields. But I'm not at home until next week to experiment.

You may have some strange problem in your process somewhere that is causing your problem, but in any case, its always a good idea to ensure what you are doing is compliant first before trying to problem solve other issues, so make sure you are only using 4:3 with these resolutions.

Well, you pointed out the mpeg.org page after I had referenced DVDDemystified.com

Well, since the resolution does comply to DVD spec its obviously possible for commercial DVDs to use a resolution of 352x240 but I honestly just find it very hard to believe you would find such a DVD, especially multiple times. I've ripped at least 1000 separate DVDs over the years and I have never seen such resolutions used for anything on a mainstream DVD release, ie: something you'd find in a rental store.

As I said, this was on the extras.

I'm curious though, how did you know what the resolution was of these DVDs if you didn't rip them?

Well, honestly I can't say that it was ENCODED at 352x240, only that it played that way.

For example, I have ripped a PAL DVD of a British sitcom called The Office. The videos are encoded at 720x576, but within each frame, the fields are replicated (not even interpolated). I have no idea why it was encoded this way, and not all the video is done that way. The title and credits have 576 lines of resolution, but not the main program (all in the same PGC). If I hadn't ripped it, I'd swear it was encoded at 352x288 (I thought 720x288 was also legal, but I see it's disappeared from DVDDemystified), due to the reduced veritical resolution.

The same thing was obvious with these extras. The vertical resolution was halved, but the image was letterboxed.

Of course now I'm wondering whether the video was encoded in letterbox on a 4:3, because scaling 240 lines up to 360 lines would not have been quite as bad as I recall seeing.

I'll try to recall which DVDs had this effect, and maybe we can find our for sure.

Xesdeeni

[tdogg4ya]

What resolution should I use to create my DVD-VCD with mpeg1? Should it be 352x480? For full screen higher quality? I made one at 352x240 and quality was low and there was alot of artifacting! Is there any quality loss when converting and preparing my 352x240 mpeg1 to higher resolution 352x480 mpeg1 in TMPGENc? Please advise!

[adam]

Well, honestly I can't say that it was ENCODED at 352x240, only that it played that way.

The same thing was obvious with these extras. The vertical resolution was halved, but the image was letterboxed.

You are confusing the film pixel resolution with the resolution itself. The actual viewable picture can be any size as long as it complies with a set resolution after the letterboxing is added. The picture may appear small on the screen, but trust me its still encoded at 720x480/576, it just has letterboxing. If you want to know the actual resolution that video is encoded at you would have to rip it and look at the file's properties or perhaps some dvd players can display that information by directly reading the flags embedded in the stream. Like I said, I have never heard of a commercial DVD which used 352x240/288 resolution. Regardless of how large the actual viewable picture is on the screen, almost all commercial DVDs are encoded at 720x480/576 and occasionally you may find some at 704/480/576 or 352x480/576. I seriously doubt that any studio would release a commercial DVD in 1/4 resolution (352x240) because it doesn't even support interlacing.

[adam]

What resolution should I use to create my DVD-VCD with mpeg1? Should it be 352x480? For full screen higher quality? I made one at 352x240 and quality was low and there was alot of artifacting! Is there any quality loss when converting and preparing my 352x240 mpeg1 to higher resolution 352x480 mpeg1 in TMPGENc? Please advise!

For mpeg1 video the DVD standard only supports 1/4 resolution, ie: 352x240/288. If you use any other resolution than your DVD will be non-compliant and may or may not play on any given dvd player. Taking a 352x240 source and increasing the resolution to 352x480 will only make the quality worse. Generally speaking, you should never increase resolution, only decrease it.

[garryheather]

Don't forget your DVD player will also be expecting audio at 48KHz (VideoCD's use 44.1KHz).