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-   -   Interlacing artifacts issue in ISO image? (https://www.digitalfaq.com/forum/news/6089-interlacing-artifacts-issue.html)

merchantord 08-24-2014 12:08 AM

Interlacing artifacts issue in ISO image?
 
I have an Oppo BDP 93 and my question concerns interlacing artifacts. I receive DVD ISO images that I burn to DVD using ImgBurn. The ISO images are of content that is filmed with an HD Camcorder. The thing is when I view these on the Oppo after burning to disc, I can see interlacing artifacts. To be fair, the same thing occurs on my PC when viewing the ISO in VLC unless I select the deinterlace option. I've contacted Oppo and they are telling me that this is an issue I will have to address before burning the image to disc. What is the best way to go about doing this whilst at the same time minimising quality loss? Many thanks.

msgohan 08-24-2014 01:54 AM

You "receive" these ISOs? It's possible whoever created them encoded the interlaced content in progressive mode.

Post a MediaInfo text log of one of the VOBs from a DVD with this issue.

lordsmurf 08-24-2014 08:18 AM

Quote:

Originally Posted by msgohan (Post 34002)
You "receive" these ISOs? It's possible whoever created them encoded the interlaced content in progressive mode.
Post a MediaInfo text log of one of the VOBs from a DVD with this issue.

^ This. :congrats:

merchantord 08-24-2014 07:19 PM

Actually I download them directly from my church's ftp site. I will get a MediaInfo snapshot together later and post it.

sanlyn 08-24-2014 08:12 PM

You don't have to make a snapshot. Use Text View in MediaInfo and copy/paste the entire Text page. Or Export the report to a text file.

merchantord 08-29-2014 11:57 PM

1 Attachment(s)
The text file is attached. I hope this will be of some help.

lordsmurf 08-30-2014 03:50 PM

I actually prefer the snapshots. :)

I can view them on-forum that way.
- I recommend Greenshot for Windows.
- Mac has a built-in tool.
- You're on your own for Linux! Wrong tool for video anyway, worse than a Mac!

Or post it as code:
Code:

General
Complete name                            : C:\Users\Mark\Desktop\VIDEO_TS.VOB
Format                                  : MPEG-PS
File size                                : 8.00 KiB
Duration                                : 33ms
Overall bit rate                        : 1 986 Kbps

Video
ID                                      : 224 (0xE0)
Format                                  : MPEG Video
Format version                          : Version 2
Format profile                          : Main@Main
Format settings, BVOP                    : No
Format settings, Matrix                  : Custom
Duration                                : 33ms
Maximum bit rate                        : 9 000 Kbps
Width                                    : 720 pixels
Height                                  : 480 pixels
Display aspect ratio                    : 4:3
Frame rate                              : 29.970 fps
Standard                                : NTSC
Color space                              : YUV
Chroma subsampling                      : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Scan order                              : Top Field First
Compression mode                        : Lossy
Time code of first frame                : 00:00:00:00
Time code source                        : Group of pictures header

Menu

There's many ways to screw up interlaced video. This sounds like that's the case here. Your only option here is to (1) go back to source, and fix it, or (2) use a deinterlace filter in software, and then redo the DVD from this already-lossy source. If you do this second method, consider something like QTGMC in Avisynth. At least Yadif in VirtualDub.

msgohan 08-31-2014 12:15 PM

As predicted:
Code:

Scan type                                : Progressive
The interlacing in the original video was corrupted by being compressed in progressive mode, so artifacts will remain even if you deinterlace the video.

Your Blu-ray player is reading the flag, so it turns off its deinterlacer. One quick and very dirty workaround would be to temporarily set the player's output to 480i. Source Direct should also send the video to the TV as 480i, I think. This way your TV will be forced to parse the nature of the incoming video content and deinterlace it using its own processing.

merchantord 08-31-2014 04:11 PM

So based on the way they are saving out the ISO images I am stuck with DVDs that will be fraught with interlacing artifacts no matter what I do. Is that a correct assumption?

msgohan 08-31-2014 05:05 PM

If you do as we suggested, you shouldn't see combing all over the place like you are seeing now. The artifacts will be things like chroma ghosting.

sanlyn 08-31-2014 09:39 PM

The playback tips could make an improvement. All that one can gather is that the video has been improperly encoded -- but we haven't seen a sample of it, so no one can make firm conclusions.

merchantord 09-01-2014 06:27 AM

Not sure that chroma ghosting would be an acceptable or preferable alternative. You would think that in this age of digital wizardry that something could be done. Oh well, guess I will just live with it. Thanks anyway.

Just out of curiosity, how should they encode the images to prevent this?

msgohan 09-01-2014 01:38 PM

They should encode in interlaced mode, and I don't know why that's "just out of curiosity" since having them do it properly to begin with is the correct solution.

I really don't think you understand what I'm saying. Our suggested workarounds are the equivalent to forcing deinterlacing in VLC, which you seemed to think was fine. Chroma ghosting is 100% preferable to viewing weaved fields, so much so that you didn't notice it before.

merchantord 09-01-2014 03:27 PM

"Just out of curiosity" was simply a turn of phrase but an altogether apt one as I'm fairly certain if I suggested they encode in interlaced mode they likely wouldn't as there are too many people involved with the image processing on that end.

As for the chroma ghosting when I glanced at photos of what it looked like online, it looked rather dreadful but perhaps these were just extreme examples. However, I am playing these back on a 65" plasma which tends to exaggerate even small flaws.

Is there a QTGMC in Avisynth MT guide anywhere?

sanlyn 09-13-2014 11:01 PM

Quote:

Originally Posted by merchantord (Post 34283)
I'm fairly certain if I suggested they encode in interlaced mode they likely wouldn't as there are too many people involved with the image processing on that end.

Mm, I don't find that argument convincing. More likely it's a matter of people who are clueless about video processing.

Quote:

Originally Posted by merchantord (Post 34283)
Is there a QTGMC in Avisynth MT guide anywhere?

There are no guides in Avisynth MT. Documentation for QTGMC comes with its download package and is in two forms, the .html that comes with the package and the text of the .avsi script itself. The first resource of choice is the html. More usage info and other details are in the Doom9 QTGMC discussion thread. The thread begins with a list of current QTGMC download links. http://forum.doom9.org/showthread.php?t=156028

We have scant information anyway and can't be of much help. The only info you've provided was text data about a "VIDEO_TS.VOB" file. VIDEO_TS.VOB is not a video file. It's a data file for a DVD menu screen.

merchantord 09-14-2014 11:06 PM

I appreciate the responses guys.

I am going to try and run some of these through Vegas when I get a chance and see how I fare there.

-- merged --

I posted the VOB file because that is what I was asked to post. What should I post?

I haven't had time to do anything in Vegas. Realistically though, am I looking at outrageous rendering times?

The playback suggestions above will not work on this particular player according to Oppo.

It looks like there should be a way to do this though and fairly quickly especially since VLC can do it on the fly.

sanlyn 09-27-2014 04:23 AM

Quote:

Originally Posted by merchantord (Post 34560)
I posted the VOB file because that is what I was asked to post. What should I post?

You did indeed post a MediaInfo text file, and thank you. However....perhaps you haven't been reading previous responses. You posted media data about a file called "VIDEO_TS.VOB". Did you notice that one of the top lines in that text report gives the duration of that VOB as "33ms"? 33ms means 33 milliseconds. That's 0.033 of a second to you and me. Why is it so short a video? Because it's not a video. It's data for the first item that plays on a DVD disc -- which in your case would likely be the menu or some sort of title screen. It's not part of the main video.

The main video content on a DVD disc would be a file sequence like
VTS_01_1.VOB
VTS_01_2.VOB
VTS_01_3.VOB
etc., each of these being 1024kb or less in size.

Note that if the VOB file name is the "zero" sequence file (i.e, VTS_01_0.VOB), it's not a video -- it's a menu. If you want to see what the DVD file structure looks like, try this page: http://www.videohelp.com/dvd#struct.

Therefore no one can say much about your actual video because we have no information about the video itself. However, we can say that the DVD has a 4:3 menu or title screen that is not encoded as 16x9. We could also make a pretty good guess that the video itself isn't HD because (a) DVD is not an HD medium, and (b) "VOB" files aren't found on HD discs. We would also guess that if the original event was photographed with an HD camcorder, as your first post says, it's no longer HD video and has likely been thoroughly screwed up in processing.

Quote:

Originally Posted by merchantord (Post 34560)
I haven't had time to do anything in Vegas.

If you don't have time to run the video thru Vegas, you won't have time for QTGMC and re-encoding.

Quote:

Originally Posted by merchantord (Post 34560)
Realistically though, am I looking at outrageous rendering times?

I think "encoding" is the proper lingo here, but the encoding time should pretty well be "normal" for whatever kind of video you're dealing with. Fact is, we still don't know what kind of video you have, how long it plays, what it's frame size or original bitrate would be, etc. All we know about is a standard definition 4:3 VIDEO_TS.VOB startup file. So we can't even tell you how long it would take a filter like QTGMC or YADIF to help restore proper frame structure, assuming that those are the tools that would be required.

Quote:

Originally Posted by merchantord (Post 34560)
The playback suggestions above will not work on this particular player according to Oppo.

True. I don't think the suggested playback settings would be available on any retail-level set top player that I know of. PC media players are different animals.

Quote:

Originally Posted by merchantord (Post 34560)
It looks like there should be a way to do this though and fairly quickly especially since VLC can do it on the fly.

Playing on the fly and deinterlace/corrective-therapy/reinterlace/re-encode aren't done by any player on the fly. Not even in Vegas.

A MediaInfo report on an actual video VOB might be more helpful. But even MediaInfo loses some detail and can report confusing data about screwed-up video files. The best analysis tool would be a few seconds of sample video that can be posted here. A VOB video file can be opened and interpreted by a free utility called DGIndex, which is often used to cut samples from MPEG2 files for posting in forums. As far as cutting goes, Vegas should be able to open and read a VOB, cut out a few seconds, and save it with smart-rendering as a small mpg.

Otherwise, there's not much more that anyone could advise.

msgohan 09-28-2014 12:07 PM

Quote:

Originally Posted by merchantord (Post 34560)
The playback suggestions above will not work on this particular player according to Oppo.

The Oppo settings I suggested trying are directly from your player's manual.

By the way sanlyn, nice catch. I skimmed right past the duration and didn't stop to consider the filename either. :smack:

merchantord 09-28-2014 07:41 PM

sanlyn and msgohan thanks to you both for your very detailed and informative responses. I really appreciate it.

I am going to try and "mess about" with these files in Vegas but the last three weeks have been VERY busy and stressful ones for me.

I will post an update though.

merchantord 11-27-2014 11:38 PM

Well still looking for something that will work. Never dealt with anything so frustrating in my life!

I can get satisfactory results in VLC on playback selecting a deinterlace filter but if I try to convert/save the program crashes every time. Are there no programs out there that will do this that actually have guides?

BTW here is a Media Info post of one of the right VOB files:

Code:

General
Complete name                            : C:\Users\Mark\Desktop\VIDEO_TS\VTS_01_1.VOB
Format                                  : MPEG-PS
File size                                : 1 024 MiB
Duration                                : 17mn 29s
Overall bit rate mode                    : Variable
Overall bit rate                        : 8 187 Kbps

Video
ID                                      : 224 (0xE0)
Format                                  : MPEG Video
Format version                          : Version 2
Format profile                          : Main@Main
Format settings, BVOP                    : Yes
Format settings, Matrix                  : Default
Format settings, GOP                    : M=3, N=15
Duration                                : 17mn 29s
Bit rate mode                            : Variable
Bit rate                                : 7 832 Kbps
Maximum bit rate                        : 9 008 Kbps
Width                                    : 720 pixels
Height                                  : 480 pixels
Display aspect ratio                    : 4:3
Frame rate                              : 29.970 fps
Standard                                : NTSC
Color space                              : YUV
Chroma subsampling                      : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Compression mode                        : Lossy
Bits/(Pixel*Frame)                      : 0.756
Time code of first frame                : 00:00:00:00
Time code source                        : Group of pictures header
Stream size                              : 980 MiB (96%)

Audio
ID                                      : 189 (0xBD)-128 (0x80)
Format                                  : AC-3
Format/Info                              : Audio Coding 3
Mode extension                          : CM (complete main)
Format settings, Endianness              : Big
Muxing mode                              : DVD-Video
Duration                                : 17mn 28s
Bit rate mode                            : Constant
Bit rate                                : 192 Kbps
Channel(s)                              : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 KHz
Bit depth                                : 16 bits
Compression mode                        : Lossy
Delay relative to video                  : 34ms
Stream size                              : 24.0 MiB (2%)

Interesting that it sees it as progressive even though I have interlacing artifacts all over the place.


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