Encoding Video8 with Megui and QTGMC

[ackboo]

hello, I am digitizing old video8 home videos. The capture part is done. For the encoding part I tried handbrake and it was good. But I also wanted to try the famed QTGMC. So far the results are excellent, I would just need some insight on how to do it properly.

I installed megui with qaac and qtgmc. There is indeed a difference in quality. Megui is a bit different from what I am used to. Can someone tell me the best way to do batch processing with megui. Do I have to generate a script for each file?

Also, I use lanczos to upscale the frames, there are many options, should I try something else?

As for the resolution I tried to resize to 736x552, 746x560, 768x576. I couldn't see a difference in quality between any of them.

sample code with a dv-avi source 720x576 cropped to 700x560 resized to 736x552

AVISource("C:\myfile", audio=false).AssumeFPS(25,1)
#deinterlace
QTGMC( Preset="Slower", EZDenoise=1,   NoisePreset="Slow"   )
crop(6, 4, -14, -12)
LanczosResize(736,552) # Lanczos (Sharp)
#denoise

sample dv-avi video
sample beach.avi

[newpball]

What are you trying to achieve with resizing?

[ackboo]

The source is interlaced anamorphic dv-avi 720x576, I considered keeping it anamorphic but now that I have more control thanks to avisynth I believe I will convert everything to square pixels. I am not done testing though, maybe keeping it anamorphic can retain more quality.

I'm concerned with the vertical upscaling, does it make sense to convert 560i to 576p?

[LMotlow]

I don't see the point. Two lossy re-encodes from a lossy original? What's wrong with the originals?

Also, I use lanczos to upscale the frames, there are many options, should I try something else?

Lanczos = oversharpening artifacts. Notably, DCT ringing.

As for the resolution I tried to resize to 736x552, 746x560, 768x576. I couldn't see a difference in quality between any of them.

I'd look again. Two lossy encodes aren't better than one, especially starting with noisy analog to noisy DV. The laws of physics are against you.

[ackboo]

I am new to this, but how do you convert 720x576 to 768x576 without resizing? Is it better to deinterlace and keep it anamorphic then?

[newpball]

I am new to this, but how do you convert 720x576 to 768x576 without resizing?

Second time, same question, what are you trying to achieve with resizing?

[ackboo]

To get a display aspect ratio of 4:3?

[LMotlow]

You miss the point. Resizing is a quality loss, no matter what you use, but Spline36 is usually preferred over others (fewer artifacts). Deinterlacing is another loss, although it's minimized doing it the right way (QTGMC). Analog to DV is another slight loss, but with compression artifacts. A second lossy encode is even more loss, and more compression problems.

Don't resize interlaced video. Deinterlace first. If you don't reinterlace, the result doubles the frame rate. Some players can handle it, some will falter.

You can do whatever you want, but you won't get 100% of what you started with. Work carefully.

To get a display aspect ratio of 4:3?

Isn't your original AR already 4:3 on playback?

I get the idea that you have some noisy borders (no tbc on capture?),head switching noise along the bottom of the original frame, and some black side border. I can understand getting rid of the big side border and the switching noise, but why resize? You can crop off the bad stuff, add pixels to restore the frame to 704x576, and encode for 4:3 DAR without resizing problems. You can't get away from the original noisy DV compression you started with, but QTGMC can clean up a lot of it. Then reinterlace and encode for 4:3 playback. You'll still be DVD\BluRay compliant at a frame size of 704x576, providing you resample the DV audio for those formats. That would work on a PC, a DVD player, a BuRay player, and TV.

[ackboo]

Isn't your original AR already 4:3 on playback?

Yes the dv-avi is anamorphic and vlc will display it with a 4:3 DAR. But I was advised here that not all players do it right. So converting from anamorphic to square pixels was to be considered. Using handbrake this meant downsizing the displayed frames from 768x576 to about 720x544. Because handbrake doesn't allow to resize up.

Don't resize interlaced video. Deinterlace first.

The script I provided should deinterlace first then resize. Unless the operations are not procedural, I don't know much about avisynth.

you won't get 100% of what you started with. Work carefully.

Well, to bring this old analog footage into the 21st century I need to deinterlace. I'd like to minimize the quality loss though.

[LMotlow]

Why are you using players that don't recognize display aspect ratios? Those same players likely don't recognize any anamorphic video correctly. That includes standard definition DVD as well as standard definition BluRay/AVCHD.

What you'll have is 4:3 PAL video at 50fps progressive and square-pixel frames. So forget about DVD players. You could encode for high bitrate BluRay instead of DVD, but at square pixel frame sizes and 50fps, DVD and SD-BluRay are out. Your playback options will be limited in some circumstances. So it's up to you.

[newpball]

But I was advised here that not all players do it right. So converting from anamorphic to square pixels was to be considered.

Well not all advice is necessarily good and written in stone.....

Some people here advice things because they love standards or think everybody only wants to view videos on DVDs.

With respect to cropping, if you crop an anamorphic source and want to maintain the correct aspect ratio you need your calculator at hand for obvious reasons.

[ackboo]

I didn't take into account dvd and blu ray players, good point. I only really cared about computer playback, hence the deinterlacing and square pixels.

English is a second language to me, I meant that since some players (that I do not use) do not recognize anamorphic it makes sense to convert to square pixels (the final files will be shared across the family).

add pixels to restore the frame to 704x576, and encode for 4:3 DAR

If I understand this right you are advising to keep it anamorphic?

Then reinterlace and encode for 4:3 playback

No loss in quality?

[newpball]

I meant that since some players (that I do not use) do not recognize anamorphic...?

Never use crappy software, it wastes your time and it annoys the engineers who made it!

[LMotlow]

The only element of quality loss with that method is re-encoding, but you can use high bitrates or go to high-quality high bitrates with h264 or even MPEG. The crop can be done without resizing or deinterlacing. Since your video is YV12 interlaced, you have to remember to crop vertically by 4's and horizontally by 2's. Say your 720x576 4:3 video has 16 pixels of side border and 8 pixels of switching noise at the bottom. I don't know what the dimensions of this video are, but you can do it this way in an Avisynth script in MeGUI to get a 704x576 frame:

Crop(0,0,-16,-8).AddBorders(0,4,0,4)

Encode that for 4:3 display aspect ratio. The only borders you'll see are 4 pixels at the top and 4 at the bottom (big deal, there will be much bigger pillarbox bars on a 16:9 display anyway no matter how big you make your 4:3 video). Yes, that video will be anamorphic.

It's pretty difficult deinterlacing and re-interlacing analog-to-DV video cleanly anyway. After deinterlacing, the fields never seem to go back together again without severe combing and fuzzy edges.

But if PC playback is your desired option, go ahead and resize to square pixel. I'd use Spline36, though, not Lanczos and avoid some artifacts. To minimize resizing artifacts, resize in only one direction (horizontally) to 768x576 -- or, if you have to crop off bad pixels as you say, leave the resulting height as-is and figure out the width. For the sake of better encoding, keep your frame dimensions mod-8. With some QTGMC deinterlacing and cleanup, you can get double frame rates, use a decently small GOP size for better motion handling (25 frames would work well), and encode to very high bitrates. You're pretty much limited to PC playback most of the time, though. Some higher-end BD players might be able to handle it OK off a USB hard drive connection. I don't know about the latter, I usually keep to standards for set top players. Not that I "love" standards. Like everyone else (except newpball) I just live with them because I don't need more problems and I hate watching movies designed for TV and the silver screen on a PC, which isn't what they were designed for. Home video8, well, you can make it anything you want.

[_Al_]

For batch encoding use this DVavi helper.zip and "make progressive MP4.bat"
If you want to modify QTGMC settings QTGMC( Preset="Slower", EZDenoise=1, NoisePreset="Slow" ) or add crop, you'd need to get into:
...\tools\subroutines\encode_progressive_mp4.BAT
and change it in proper place in there,...., placebo or very slow preset do not work, also some advanced settings, your would work I think, but I think you have QTGMC properly set in PC so it would work with whatever setting

or if you need your custom x264 command line, you can modify it in that very same BAT.

If you encode interlace , you can do it with "make interlace MP4.bat" there also, but I would not. There is always player that cannot deinterlace properly.

Your archive is those DVavi's, you store it, you keep it, not sure why guys here are at you here about not resizing etc.

[mammo1789]

But if PC playback is your desired option, go ahead and resize to square pixel. I'd use Spline36, though, not Lanczos and avoid some artifacts. To minimize resizing artifacts, resize in only one direction (horizontally) to 768x576 -- or, if you have to crop off bad pixels as you say, leave the resulting height as-is and figure out the width

He can try super resolution resizer like http://www.infognition.com/ it gave me more "clear" upsize than spline36. Newer devices ( like tablets and media players) handle 50p/60p h264 videos with ease, although they are not "standard" like DVD or blyray wich I think are less and less used especially with the flood of new smart TV's almost all off them have media players that can play pretty much any mp4 mkv vob files.

[LMotlow]

True. Why buy a professional product like DVD or BluRay? Many new forms of video are around these days. Digital video started out as higher quality alternatives to VHS. Today's users are quickly finding new ways to make digital video look worse than VHS ever did.

[newpball]

He can try super resolution resizer like http://www.infognition.com/ it gave me more "clear" upsize than spline36.

On a video 8 source?

That does not make any sense whatsoever.

Super resolution certainly could work on very high quality video sources using a (near) lossless codec. Most run of the mill codecs basically work on motion compensated residue images with either DCT or wavelet type algorithms applied to it, this unfortunately runs completely counter to getting anything from super resolution.

[ackboo]

I added a sample video in the first post.

I ran some tests, managed to find slight differences between lanczos and spline36. The spline36 frames are a bit softer and maybe more accurate but you don't really see it while playing the video. I'll use that instead of lanczos anyway.

The differences between a 746x560 resize and 768x576 resize are negligible in my opinion. You can spot slight variations here and there but the resize has an effect anyway.

I tried an anamorphic encode but it was less clear than the rest, I guess I failed it.

VLC gives me the following information :

746x560 : resolution 752x578 - display resolution 746x560

768x576 : resolution 768x578 - display resolution 768x576

700x560 anamorphic : resolution 704x578 - display resolution 700x560

The differences are due to the encoder right?

[_Al_]

Did you crop that anamorphic video?
Resolution should be 720x576, VLC in CODEC tab should inform about that resolution and proportion should be alright on screen if encoded with --SAR 16:15,

if you decide to crop anamorphic video, horizontal resolution , SAR is not changing, think of SAR as a coefficient that stretches horizontal resolution for any differential (math. expression) of horizontal resolution, any part of horizontal resolution, but, it could be even quite confusing if anybody looks at video closely or tries to work with video later, you might expect anamorphic video with regular 720x576 resolution, but with different resolution who would expect anamorphic video, it is kind of weird... cropping vertical resolution makes it even more weird, possible and legal, players should handle that (or maybe not, your case) , but weird

[ackboo]

I cropped the original video to 700x560 and added the 4:3 flag in megui the result wasn't pleasing to the eye.
VLC gives me those weird info, I don't know what to make of it.

I need to crop because of the black bars around the frame, see first post for a video sample.

I'll try anamorphic again in megui, there are many options.

[ackboo]

I checked with mediainfo, no sign of those weird resolutions. I guess my version of vlc (2.2.1) is buggy.

for the anamorphic one :
Width : 700 pixels
Height : 560 pixels
Display aspect ratio : 4:3
Original display aspect ratio : 4:3

Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.1
Format settings, CABAC : Yes

[_Al_]

I tried that beach sample, using:

Avisource("sample beach.avi")
QTGMC( Preset="Slower", EZDenoise=1,   NoisePreset="Slow"   )
crop(6, 4, -14, -12)

then x264 cmd line:

x264.exe --crf 17 --sar 16:15 --ref 6 --tune film --vbv-bufsize 25000 --vbv-maxrate 23000 --output out.h264  input.avs

and I got this, all seems to be ok in VLC:

[_Al_]

I have VLC 2.1.3

[ackboo]

It looks good, I'll try to copy your parameters and make some comparisons. Thanks a lot.

[LMotlow]

The DV sample has typical analog to DV problems: sloppy interlace, line twitter, aliasing, DCT ringing, mosquito noise. Otherwise some colors exceed RGB 255, there's some right-hand chroma ghosting (especially red), and there's an ugly stain on the right border. Like many such captures , once you separate fields or deinterlace, it never goes back together the same way again. So for any cleanup work, looks like you're stuck with progressive.

I thought you said you didn't want anamorphic because you were warned that most players don't render aspect ratios correctly from anamorphic video? (wonder where you heard that).

[ackboo]

I thought you said you didn't want anamorphic because you were warned that most players don't render aspect ratios correctly from anamorphic video?

It was suggested by some members in this thread :
https://forum.videohelp.com/threads/370064-Preserving-anamorphic-aspect-ratio-while-cropping

If you absolutely need a square pixel equivlent (target player doesn't work with non-square, etc)...

I resize to square pixels as then there's no need to rely on a player displaying the video with the correct aspect ratio. Not all players display anamorphic MKVs/MP4s correctly and will just display it as though it consists of square pixels anyway.

But I never said most, I said some, since the files will be used by non techies I thought it would be safer.

[ackboo]

Hello,

The encoding is in progress. I settled for 700x560 anamorphic because it made more sense in the end.

Thanks for your help everyone.