More deinterlacing issues

[Hypersonic1]

I just bought a professional S-VHS VCR. Unfortunately, a couple tapes are so bad, that they will not play well like they used to. The tapes were converted about a year ago by a company iMemories to a digital format, but I only have the 30p versions from their web site. I was told that it is best to keep them interlaced, so now I don't know how to capture those couple bad tapes.

I am thinking about keeping all of my videos at 30p. If I decide to keep everything interlaced, can I deinterlace to Bob first, edit it, and then reinterlace without losing quality?

[newpball]

I am thinking about keeping all of my videos at 30p. If I decide to keep everything interlaced, can I deinterlace to Bob first, edit it, and then reinterlace without losing quality?

That depends how you deinterlace and what you edit.

Deinterlacing a source can be lossless but it is most often not. And of course if you edit by using filters on frames information related to the interlaced source may be destroyed.

[Hypersonic1]

Wow. Interlacing is a nightmare to work with. I am pulling my hair out right now just trying to figure out what to do. I wish interlacing was never invented.

I am about ready to say screw it, and leave it at 30p. Then I will wait for AI to be at human levels, so there will be far more sophisticated tools in the future.

[sophisticles]

Deinterlacing a source can be lossless but it is most often not. And of course if you edit by using filters on frames information related to the interlaced source may be destroyed.

How can you "losslessly" deinterlace a source? I have never seen any method that is capable of doing that, hell I would say that once something is interlaced you are better off leaving it that way because I have never found a truly high quality way off doing it, not even with such much hyped tools like QTGMC.

[johnmeyer]

1. You cannot losslessly deinterlace a source. That is incorrect. Deinterlacing always degrades the video and that degradation is permanent. Therefore, IMHO, you should never deinterlace unless you are posting video to a web site (although for some sites, like YouTube, this is optional); or unless you are resizing, in which case deinterlacing is mandatory.

You certainly do not want to deinterlace video that you've already captured as interlaced.

2. Deinterlaced video is not "better" then interlaced video. This is a common misconception.

3. Interlaced video can be easily handled by TV sets, and 1080i is a common broadcast format.

Why do you want to deinterlace? If you are not re-sizing the video and are not posting on a web site, I would recommend you keep it interlaced.

[Hypersonic1]

How could I retain it as interlaced? Premiere Pro always exports as progressive.

[poisondeathray]

Premiere can export interlaced. If your asset(s) are interlaced, project settings are interlaced, export settings are interlaced, then the output will be interlaced

But if you started out with 30p versions from the web site - then you cannot produce standard interlaced content . Because 1/2 the data had been already discarded

[manono]

1. You cannot losslessly deinterlace a source.

You can if it's to be followed by reinterlacing it which is what the original question was, and if you save to a lossless codec. You use a bob deinterlacer that keeps one of the fields unchanged (not QTGMC). Later on you'll reencode to a final format and that'll be lossy, which is maybe what you meant by your statement. And, as pdr said, if the source is 30p then there's no point in either bobbing or reinterlacing.

[Hypersonic1]

Thanks. Now it is exporting. However, there is a freeze frame every 13 frames. Also, it seems like the field order is reversed, but upper and lower are both returning the same results.

[poisondeathray]

Thanks. Now it is exporting. However, there is a freeze frame every 13 frames. Also, it seems like the field order is reversed, but upper and lower are both returning the same results.

If there is a "freeze frame" every 13 frames in the source, obviously there will be in the export as well

Not enough information.

You need to provide more details about the source. Where is it from , what type of content etc...Start with mediainfo (view=>text) , copy & paste

Also, your sequence settings, export settings

[Hypersonic1]

ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L3.1
Format settings, CABAC : Yes
Format settings, ReFrames : 3 frames
Format settings, GOP : M=4, N=29
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 20s 20ms
Bit rate mode : Variable
Bit rate : 4 309 Kbps
Maximum bit rate : 6 000 Kbps
Width : 704 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate mode : Constant
Frame rate : 29.970 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Bottom Field First
Bits/(Pixel*Frame) : 0.425
Stream size : 10.3 MiB (96%)
Language : English
Encoded date : UTC 2015-03-29 22:41:42
Tagged date : UTC 2015-03-29 22:41:42
Color range : Limited

..

[poisondeathray]

Is that mediainfo report of the SOURCE video ? or OUTPUT video ?

Can you post a sample of the unprocessed SOURCE video? You can upload it directly here

As mentioned earlier, if you start with a progressive 29.97 video, you cannot make a true interlaced (in terms of standard interlaced content) video . Upper or lower field won't make a difference on progressive content.

Not trying to confuse you , but you can have interlaced encoding, yet progressive content . It's the content that matters most.

[Hypersonic1]

It is definitely interlaced because the interlacing options have an effect in VLC. It can discard frames.

[poisondeathray]

Yes, it is interlaced content, but it's TOP field first, not bottom

Where is Sequence.mp4 from ? How did you get it? What is the workflow history ?

Yuu didn't post your sequence settings.

If you match sequence settings in premiere and AME, the input should be similar as the output (no duplicate frames or fields) .

[Hypersonic1]

I tried switching it to upper first, but no difference.

[poisondeathray]

Did you try adjusting the sequence settings as well ? Upper for sequence settings, upper for export settings (both), and interpret the file as Upper as well (right click the clip) . Premiere might be "guessing" the wrong field order because it's encoded Bottom field first, but the content is Upper field first

[Hypersonic1]

That solved the problem. I forgot to change the sequence settings. Actually, I couldn't change the sequence settings; I had to create a new sequence.

How does this work with multiple video tracks, a clip on top of another?

[poisondeathray]

How does this work with multiple video tracks, a clip on top of another?

When you place a clip on top of another (and they are both the same dimensions, and AR), and you don't do anything else, only the "top" clip will show. You won't "see" the lower clip because it's "covered up" by the top clip

But I have a feeling that wasn't what you wanted to ask ?

Can you be more specific or clarify your question ?

[newpball]

1. You cannot losslessly deinterlace a source.

You can if it's to be followed by reinterlacing it which is what the original question was, and if you save to a lossless codec. You use a bob deinterlacer that keeps one of the fields unchanged (not QTGMC).

Correct.

[Hypersonic1]

Let's say the opacity of the top video clip is 50%, the bottom video clip should obviously show through. I just tried it, and it is. How is the interlaced preserved?

The main reason why I initially wanted to deinterlace was because I want to overlay multiple captures by using multiple video tracks. This would average the pixel values, which would reduce the amount of noise in a logarithmic fashion for each capture. I just thought I had to convert to progressive in order to do this.

[johnmeyer]

I agree that it would be useful to know more about your capture setup. Is your capture setup creating an MP4? That seems to me to be an even poorer choice for a capture format than MPEG-2. I already described what I would prefer. Most SD material is BFF, and most HD is TFF, but those are not hard and fast rules. What IS a hard and fast rule is that you need to know whether your source video is bottom or top field first, and your scripts and workflow need to be adjusted, if necessary, to conform to that field order.

[poisondeathray]

Let's say the opacity of the top video clip is 50%, the bottom video clip should obviously show through. I just tried it, and it is. How is the interlaced preserved?

The main reason why I initially wanted to deinterlace was because I want to overlay multiple captures by using multiple video tracks. This would average the pixel values, which would reduce the amount of noise in a logarithmic fashion for each capture. I just thought I had to convert to progressive in order to do this.

Yes, interlace is preserved within premiere if you have it setup properly

Yes, you can average multiple captures - and you don't need to convert to progressive. This technique is discussed in several threads here and doom9. There are some avs scripts and functions that can do this for your as well . It's critical, however, that you have no dropped frames and everything is aligned

And as john suggested, you should provide more info about your capture setup, and even the "damaged" tapes - there might be some things you can do about those

[Hypersonic1]

I agree that it would be useful to know more about your capture setup. Is your capture setup creating an MP4? That seems to me to be an even poorer choice for a capture format than MPEG-2. I already described what I would prefer.

My capture setup is creating an MPEG-2, but then I have to use Handbrake to convert to a constant frame rate because variable frame rate + Premiere Pro results in audio sync problems.

What's wrong with mp4? Isn't it a container, and not a codec right?

[Hypersonic1]

I am using an Ezcap with composite cables. I have very little money to spend since I have a tight budget. I already convinced my parents to spent a lot of money sending my tapes to iMemories, which I only have the 30p videos to download from their cloud service. What are the chances that they have interlaced versions of those stored on their servers? I figure since they allow DVDs to be made, they would have interlaced format. There is no 30p DVD standard from what I read, although it would work on most DVD players.

[Hypersonic1]

I would like to add that I have about 10 VHS-C tapes. About half of them converted by iMemories have significant tracking issues, but they do not appear on my VCR. The 10 or so Hi8 tapes that I have turned out alright by iMemories.

[poisondeathray]

I agree that it would be useful to know more about your capture setup. Is your capture setup creating an MP4? That seems to me to be an even poorer choice for a capture format than MPEG-2. I already described what I would prefer.

My capture setup is creating an MPEG-2, but then I have to use Handbrake to convert to a constant frame rate because variable frame rate + Premiere Pro results in audio sync problems.

What's wrong with mp4? Isn't it a container, and not a codec right?

Nothing wrong with MP4 as a container, but you are re-encoding with a lossy format using handbrake. This means you incur avoidable quality loss

Handbrake cannot "rewrap" video by swapping containers . Rewrapping is lossless, re-encoding witha lossy format is NOT.

What's wrong with keeping the original MPEG2 format that you captured in? Why is it VFR in the first place ? Are you sure ? Most captures will be CFR, unless they are webcam variety

I already convinced my parents to spent a lot of money sending my tapes to iMemories, which I only have the 30p videos to download from their cloud service. What are the chances that they have interlaced versions of those stored on their servers? I figure since they allow DVDs to be made, they would have interlaced format.

That 's something you should ask them directly

[manono]

My capture setup is creating an MPEG-2, but then I have to use Handbrake to convert to a constant frame rate because variable frame rate + Premiere Pro results in audio sync problems.

A variable framerate MPEG-2 capture? Are you sure about that? Do you have a MediaInfo text file to confirm that? Are you sure you don't mean variable bitrate? You realize, don't you, that creating these intermediate MP4s is just degrading a video quality that wasn't so good to begin with? If you absolutely have to create an intermediate that works with Premiere Pro, can't it be a lossless AVI?

Edit: too slow, pdr beat me to it.

[Hypersonic1]

What's wrong with keeping the original MPEG2 format that you captured in? Why is it VFR in the first place ? Are you sure ? Most captures will be CFR, unless they are webcam variety

Oh, nevermind. I am thinking of the Elgato capture device I had. That was variable framerate. However, I had to get rid of it because it wasn't compatible with a lot of capture software. The software included with Elgato would deinterlace and apply filters automatically, with no manual controls.

The reason why I converted from MPEG-2 to some other format in Handbrake is because Premiere Pro CS6 doesn't work well with MPEG-2.


Premiere Pro CC is giving me problems with flickering lighting when I stack multiple effects on clips.

MPEG-2 is also lossy by the way.

[Hypersonic1]

If you absolutely have to create an intermediate that works with Premiere Pro, can't it be a lossless AVI?

What about lossless H.264? Set the quality slider to 0 in Handbrake.

[poisondeathray]

Premiere Pro CC is giving me problems with flickering lighting when I stack multiple effects on clips.

Are you sure they are aligned?

MPEG-2 is also lossy by the way.

Yes it's lossy. But that's considered your "original" , since you're not going to upgrade your capture setup.

The point is you're not incurring ADDITIONAL, AVOIDABLE quality loss .

What about lossless H.264? Set the quality slider to 0 in Handbrake.

You would have to set the profile as well, or handbrake will actually use "1" (not lossless). The filesize will be 5-10x the size as the original, and not be supported by premiere (PP doesn't support x264 lossless). So you should use the original if you can





Try re-wrapping the captures, either into another program stream (e.g. with ffmpeg) , or into a transport stream with tsmuxer



Are there any other settings in your capture setup ? Can you bump up the bitrate for example ?