From AVI to DVD - Upper or Lower Field First problem

[FrankDrebin]

Hello everybody.

During the past few days I've been attempting to capture some old VHSs of mine and convert them to DVD format. First of all, these VHSs were recorded in PAL format, the VCR I'm using uses PAL standard, I live in a PAL based area and the device I'm using is the TerraTec AV Grabster 250 (I know it's not a professional tool, but it does a decent job for my purposes). As far as I know, the TerraTec device features "auto field-order detection", so there's no way I can manually check or set this while capturing. Now, I've got a series of interlaced AVI files (captured in MJPEG format) which I'm willing to burn in DVD format. Here's where my problems start: what I typically do is apply all the filters in VirtualDub, start its frameserver mode and convert the AVI file in MPEG-2 via TMPGEnc. When TMPGEnc analyzes the video, it automatically detects "Bottom Field First" sequence. In order to double check this, I tried a method which I found on this forum: go to the "Advanced" tab within the "MPEG Setting" menu of TMPGEnc and test the Deinterlace "Even-Odd field (Field)" filter. If I leave the "Bottom Field First" option activated, the playback of the video is fine, whereas it shows severe stuttering if I were to change the field order to "Top Field First". At this point, I must assume that the TerraTec device captures videos in "Bottom Field First" mode.

After my AVI file has been converted to MPEG-2, I try burning it to DVD: the software I'm using (Corel Video Studio Pro X5) asks me if I want the video to be burned using either Top or Bottom Field First. I've tried both ways and here's the strange outcome:

- Top Field First: the video is affected by severe stuttering. Ok, I kind of expected this to happen, so no big surprise.
- Bottom Field First: the video is no longer affected from stuttering but there are some areas of each frame which still show some "deinterlacing". Check the image attached to this post to see what I mean. Look at the tie of the man standing on the right, the poster behind him and the red can on the right, on top of the shelf.

Another strange thing: these "deinterlaced areas" do not appear in the MPEG-2 file generated by TMPGEnc. If I open the video file, let's say, with VLC and apply some deinterlacing filters to it, everything is fine.

What am I doing wrong?

Thanks in advance for your help.

[DB83]

I don't quite understand when you say "I've got a series of deinterlaced avi files". Your captures will be interlaced - it seems to be bottom-field first which is usual for avi (top-field for mpeg2). If you have deinterlaced the captures and then re-interlaced them when encoding to mpeg (for the dvd) it is possible that field order has been swapped or even screwed up.

Just keep the avis interlaced and process as interlaced.

[FrankDrebin]

I don't quite understand when you say "I've got a series of deinterlaced avi files". Your captures will be interlaced - it seems to be bottom-field first which is usual for avi (top-field for mpeg2). If you have deinterlaced the captures and then re-interlaced them when encoding to mpeg (for the dvd) it is possible that field order has been swapped or even screwed up.

Just keep the avis interlaced and process as interlaced.

I'm sorry, I miswrote that part: I capture the AVIs as interlaced.
I've just corrected my first post.

[DB83]

Might I suggest one step less.

You are editing in vdub so export from that to a lossless avi - lagarith or huffuv. Import the avi in to Corel and let that just encode to mpeg2 once.

[FrankDrebin]

Might I suggest one step less.

You are editing in vdub so export from that to a lossless avi - lagarith or huffuv. Import the avi in to Corel and let that just encode to mpeg2 once.

I've just tried encoding the video using Huffyuv and then importing the AVI file into Corel VS in order to get the final DVD ISO file. I tried creating the final disc image file using both upper field first and lower field first: now both of them cause stuttering!

[DB83]

Well if both are causing stuttering it is not a field-order issue. Well, at least is should not be.

I do not see your PC specs so I wonder if your system is fast enough to process lossless video.

What I will suggest is that you upload a short sample of unprocessed mjpeg capture. I have an older version of Corel (when it was Ulead). I also have Ulead DVD Movie Factory. Some Ulead programs would create a dvd from dvd-compliant mpeg2 without re-encoding but Movie Factory, as far as I could tell, always re-encoded which is why I suggested one step less. But if you also upload the same capture but now encoded as mpeg2 using your current tools I can also test this in other Ulead software which I know does not re-encode if it is dvd-compliant

[FrankDrebin]

Here is a short segment of one of my captures in MJPEG format: https://forum.videohelp.com/attachment.php?attachmentid=19286&d=1376141541

How would you like me to make the MPEG-2 attachment? Via TMPGEnc? Corel VS?

[DB83]

Thanks. Via TmpGenc just as you did before.

It's getting late now and I'm trying to debug a php script so if you care to upload I will check them out tomorrow.

[DB83]

There seems to be an error with the rar file. Just upload here as an attachment - no rar.

Edit: You appear to have posted the link to the attachment and not the actual attachment. Select 'Advanced Reply' and click on the PaperClip to upload the attachment.

[FrankDrebin]

Got it. Ok, I'll upload the videos tomorrow. Thanks for your help.

[jagabo]

What am I doing wrong?

The image is showing an interlaced frame that has been resized without taking into account it is interlaced. The two fields that make up two separate images have been partially blended together so that they are no longer two separate images.

Note that interlaced analog video is neither top field first nor bottom field first. It is just an alternating sequence of top and bottom fields. It's not until those fields are digitized and woven into frames that the acquire a field order. The capture device/software can start with a top field, then add the next (bottom) field, creating a TFF frame, or it can start with a bottom field then add the next (top) field creating a BFF frame. The player needs to know the field order in order to display the two fields in the correct order.

[DB83]

I did not consider resizing since I could see the 'usual suspects' on the bottom of the frame.

You may well be correct as the OP did not state what filtering he did - I was gonna consider that after seeing some samples.

[FrankDrebin]

Here are the two sample clips which DB83 asked me:

- Captured AVI file compressed in M-JPEG (no filtering whatsoever): http://db.tt/d2hw4PMx
- AVI file compressed via TMPGEnc in MPEG-2 (lower field first, no filtering whatsoever): http://db.tt/6pd9dSce

The technical details of the computer I'm using are here (HP Pavilion g6-2212sl): http://h10025.www1.hp.com/ewfrf/wc/document?docname=c03531622&cc=us&dlc=en&lc=en&jumpi...01_title_r0001

The first screenshot I posted is misleading, you're right: the screenshot itself was taken from DVBViewer, I just took it and posted the image here with no resizing.

[DB83]

Thanks for the clips.

According to mediainfo the avi is top-field first whereas the mpeg is bottom field first.

I will take a closer look at them this afternoon but one thing occured to me this morning. Ulead products had their own way of describing field-order. They used the terms Field-Order A and Field-Order B. Now you would think that A is top but not in Ulead parliance. It is actually bottom. I just wonder if this kookiness carried on with Corel.

[sanlyn]

Both samples play properly as bottom field first. Besides being damaged and tracking without the help of a line-level tbc (note how the edges of doors and walls have a constant "wiggle"), some rather severe dot crawl adds a lot of noise to motion. The avi capture shows signs of dropped frames, which were apparently replaced by duplicate frames (duplicated frames I noticed were 70-71, 82-83, 106-107).

Frame 76 has a bad frame hop and top border flash (green). Using SeparateFields(), it's the Odd field that hops and flashes, with the Even field steady. Another oddity is that odd and even fields appear alternately displaced or "leaning" a few pixels to the left or right.

The same problems are in the mpeg, which has lost detail by undergoing a second encode (the high constant bitrate is a waste of data bits, but having started with a lossy capture to begin with I guess you're stuck with it). The same duplicate frames appear, but watching them deintelaced reveals that fields have been swapped somehow in those areas and motion is reversed for a couple of fields. The second encode is softer and has lost detail, contrast, and saturation. You can still see interlace effects on a PC screen.

Applying filters in VirtualDub to intelaced video is sometimes OK, sometimes not, depending on what you're trying to fix. The horizontal rip across the top, duplicate frames or fields, frame hopping, border noise, and excessive interlace combing can't be fixed in VirtualDub. VDub has a dot crawl filter, but it's one of the more destructive filters you'll find that simply blurs everything in sight.

You lose more definition by allowing Corel's so-so encoder to re-encode your entire video for the third time.

[jagabo]

The source was shot with a video camera, not film, so it is fully interlaced video. Both files are bottom field first and correctly encoded. DVD players and TVs are designed to handle interlaced video so there's no need to deinterlace for DVD. The MPG file has a bitrate of 9800 kbps with peaks over 10700. Those peaks are too high for DVD. And 9800 kbps average is right at the borderline (too high if the audio is over ~250 kbps).

After my AVI file has been converted to MPEG-2, I try burning it to DVD: the software I'm using (Corel Video Studio Pro X5

It's not clear to me if you are giving CVSP5 the AVI file or the MPG file here. If the MPG file, Corel Video Studio may be recompressing the file because of too high bitrate. I don't know why it would ask you for the field order because the field order is flagged in the MPG file. The implication is you are giving it the AVI file. AVI doesn't really have a mechanism to flag a video as interlaced, the field order, or the pixel/display aspect ratio. That would explain why the program asked you about the field order and why it resized improperly.

[FrankDrebin]

Both samples play properly as bottom field first.

Thanks for your reply. They do play fine as bottom field first, but the MPEG-2 sample, for whatever reason, doesn't play fine after bein turned into DVD format. Top field first causes stuttering, Lower field first doesn't cause stuttering but there still are some "interlaced" areas visible.

Besides being damaged and tracking without the help of a line-level tbc (note how the edges of doors and walls have a constant "wiggle"), some rather severe dot crawl adds a lot of noise to motion. The avi capture shows signs of dropped frames, which were apparently replaced by duplicate frames (duplicated frames I noticed were 70-71, 82-83, 106-107). Frame 76 has a bad frame hop and top border flash (green). Using SeparateFields(), it's the Odd field that hops and flashes, with the Even field steady. Another oddity is that odd and even fields appear alternately displaced or "leaning" a few pixels to the left or right. The same problems are in the mpeg, which has lost detail by undergoing a second encode (the high constant bitrate is a waste of data bits, but having started with a lossy capture to begin with I guess you're stuck with it). The same duplicate frames appear, but watching them deintelaced reveals that fields have been swapped somehow in those areas and motion is reversed for a couple of fields. The second encode is softer and has lost detail, contrast, and saturation. You can still see interlace effects on a PC screen.

I could start all over again and do a second capture using Huffyuv. Would that be a better decision as far as the lossy coding is concerned? Unfortunately, I don't have neither a TBC nor a professional VCR. As you probably have guessed already, I'm trying to do a "homemade conversion" from VHS to DVD. I know that the results cannot be tremendously great, but I'm happy with what I can get just with these tools.

Applying filters in VirtualDub to intelaced video is sometimes OK, sometimes not, depending on what you're trying to fix. The horizontal rip across the top, duplicate frames or fields, frame hopping, border noise, and excessive interlace combing can't be fixed in VirtualDub. VDub has a dot crawl filter, but it's one of the more destructive filters you'll find that simply blurs everything in sight.
You lose more definition by allowing Corel's so-so encoder to re-encode your entire video for the third time. Those losses include several unmanaged, back-and-forth colorspace changes.

The tapes I'm using are very old, in different parts the tapes were eaten by bad VCRs and they've been watched over and over again extensively. Unfortunately, the source material isn't in very good condition as you can tell...

[jagabo]

The tapes I'm using are very old

Is this Are You Being Served? Why bother doing this yourself? It's available on DVD. Presumably with much better quality than you're ever going to get with damaged tapes and a bad VHS deck.

[DB83]

What worries me is the capture software and this "auto field-order detection". Field-order should AFAIK be a constant process so if the software thinks that field-order has changed we have problems. And that 'problem' may well have manifested itself it the incorrect report of field-order in the avi.

To echo the above, field-order aside, the mpeg2 encode should be variable bitrate. I would have thought that tmppenc can create dvd-complaint mpeg2. Whether Corel, in this disguise, can process it without re-encoding, is another matter. But do check for such parameters. Certainly some Ulead products can do this without breaking into a sweat.

[DB83]

The tapes I'm using are very old

Is this Are You Being Served? Why bother doing this yourself? It's available on DVD. Presumably with much better quality than you're ever going to get with damaged tapes and a bad VHS deck.

No.

I half recognise it and this is Italian tv so the OP way well want the dubbing.

[DB83]

One more question.

What software , apart from capture, comes with the device. Does that make dvds so does not then involve Corel.

You may even try avstodvd which, naturally, will re-encode the avi whether it is mjpeg or anything else.

[sanlyn]

Capturing to lossless huffyuv or Lagarith would retain more data, if your capture setup will allow it. However, capturing to lossy MJPEG first and then decoding to huffyuv/Lagarith wouldn't offer the same advantages. As it is, cleaning some of the horizontal streaks and other noisy stuff would require working with lossless media anyway in Avisynth. Capturing lossless is cleaner, since you'd have to clean in lossless and will be going to a different encode anyway; it doesn't solve problems that require a line tbc of some kind. DVD recorders can be used as pass-thru devices to exploit their built-in line and frame sync circuits -- but not all DVD-R's can be used in that manner, and older products are better at it than new ones. Rather than record with the machine, it's used to simply "play through" without recording, using VCR as input and feeding the DVD-R's output directly to a capture setup. Several recent threads discuss this technique.

Yes, everyone is familiar with old, damaged, faded tape. All too common and troublesome. This forum has seen worse, believe me.

The MJPEG is at least workable at its high bitrate. Between the MJPEG phase and intermediate cleaning you want to avoid lossy encoding. That would lead to a good encoder, for which I'd suggest the popular TMPGenc or HCenc as superior to Corel. Follow that with authoring and burning; many excellent free tools are available that won't re-encode.

[FrankDrebin]

@jagabo: no, the videos I am trying to capture aren't from "Are You Being Served?". They're from an old and quite rare Italian sit-com which has never been released on DVD. I enjoyed the series when I was a kid, so my parents recorded some episodes for me on VHS. I am responsible for watching the tapes over and over again, almost destroying them! Unfortunately, this tv series has never been broadcast again, so I've never been able to re-record it properly via DVB.

@DB83: I will try re-encoding an AVI sample in MPEG-2 using TMPGEnc, this time trying to respect DVD standards.

Concerning your second question, I capture via VirtualDub (latest version) using the M-JPEG codec set at the highest quality possible (20). The software which came along with the TerraTec capture device is called "Ulead DVD Movie Factory 3" but I've never used it so far.

@sanlyn: I've just remembered that, when I capture via VirtualDub, I always activate the Noise Reduction option, manually setting the treshold. Higher values generate more blending and unnatural pictures, of course. I usually tend to use little values. May this also be the cause for some of the noise you detected in my video sample?
I think that VirtualDub allows you to capture via Huffyuv. I've never used Huffyuv before, yesterday I noticed it requires a lot of hard disk space! Each episode of the tv series I'm trying to capture is approximately 20-25 minutes long. How much hard disk space should I need in your opinion?
I am familiar with the "VCR->DVD-R" combination, but, unfortunately, I don't have a DVD recorder available.
So, if I properly understood your suggestions, I should try doing the following:

- Capture videos using Huffyuv.
- Doing all the filtering and cleaning up with VirtualDub filters/AVISynth scripts still leaving the videos in Huffyuv format.
- Convert the videos in MPEG-2 format using TMPGEnc, for instance.
- Burn everything on DVD using some programs other than Corel.

What about these crazy field order problems I'm having?

I've got another question for you: so far I captured each individual episode into a single AVI file. I was planning to convert each individual file to MPEG-2 format and then burn them on DVD. Would it be better to capture all of them into a single AVI file, instead?
What bitrate should I use to encode the episodes on DVD (I will probably use Dual Layer disks)? How can I know this in advance?

[jagabo]

@jagabo: no, the videos I am trying to capture aren't from "Are You Being Served?".

Sorry, my mistake.

What about these crazy field order problems I'm having?

You're not having any field order problems.

What bitrate should I use to encode the episodes on DVD (I will probably use Dual Layer disks)? How can I know this in advance?

It depends on how much running time you plan to put on each DVD. Use a bitrate calculator. Just as a rough guide: at max bitrate (~9600 kbps video, plus audio) you can put one hour on a single layer DVD. If you want to put 2 hours on a DVD use half that amount.

[DB83]

Ulead DVD Movie Factory three would probably not work for capture. It is quite ancient and the old stuff was not guaranteed to do analogue capture beyond XP. If it did work then capture would be straight to mpeg2. Your Corel program can do that anyway.

I noticed vdub as the writing utility for the avi but I really did not think you were capturing to mjpeg with that. Lossless codecs huffyuv and lagarith do take a lot of disk space - 30 to 60 gig per hour - but if you can manage it then it is worth it.

These crazy field issues are, err humm crazy which I put down to the capture sofware. It may now be down to the codec.

Personally, I would capture them as single episodes. You can always do a menu with a 'play all' option. If they are all as one then you would do it as chapters.

Bitrate is an easy one to answer. One hour on a single layer disk is 8000 kbps so 3 30 minute episodes would be 5,500 - 6000 kbps and still an acceptable picture. You can not exceed 8000 (or atleast by much - the rest is for audio) so if you are using dual layer then you just get more episodes.

One thing tho. When using dual-layer you are quite limited to media, even less than with good quality single-layer.

[sanlyn]

- I have to agree with jagabo. The sample you posted is bottom field first. It should remain that way.

- A bitrate of 6200 VBR (target 6200, max 8000, 2-pass in TMPGenc or HCenc) should give you 90 minutes on a DVD-R. You might be able to push the target to 6500 VBR and get close to that time. If you want more on a disc or want a higher bitrate, use DVD+R dual layer. It's done all the time.

If you're using the Wizard in TMPGenc 2.5, stop using it. Try the Advanced interface in TMPGenc or HCGUI (for HCenc) to get the best from these encoders. You might have to read a little online Help or ask some questions here, but it's not that mysterious to know a little more about how to get better encodes.

[FrankDrebin]

You're not having any field order problems.

I've just tried the following: I took one of the AVI captures I did, converted it in MPEG-2 format with TMGEnc (bitrate: 8000 kbps, no audio track, lower field first) and played it on tv. Again, no stuttering, but there are still these "interlaced artifacts". I took a picture of the tv screen with my digital camera, take a look at the attachment to this post.

If I don't have any field order problems, what are those interlaced areas caused by? What am I doing wrong? No filtering or resizing was done to the video prior to its MPEG-2 conversion.

[jagabo]

You have interlaced video, there's no doubt about that. The field order is the order the fields are displayed in -- you're only supposed to see one field at a time. The problem you're having is that both fields are being displayed at the same time. And the video is being resized without keeping the two fields separate.

[FrankDrebin]

You have interlaced video, there's no doubt about that. The field order is the order the fields are displayed in -- you're only supposed to see one field at a time. The problem you're having is that both fields are being displayed at the same time. And the video is being resized without keeping the two fields separate.

So, how could I fix that?

[jagabo]

I don't know where the problem is happening. The original AVI file is fine. The TMPGEnc encoded file is fine. The problem is happening somewhere after that. Post the VOB file that Corel Video Studio made. You can use DgIndex or Mpeg2Cut2 to trim out a short piece if necessary.