BD3D2MK3D v1.17: Convert 3D BDs or MKV to 3D SBS, T&B or Frame-sequential MKV

[r0lZ]

OK, I did some Full-TAB tests and everything works as expected, at least here.

But I've also played with the settings of the players, and I have managed to get something identical to what you have shown in your TAB screenshot above. So, now, I suspect that your player doesn't have the correct settings to play 3D movies with the correct aspect ratio.

What player do you use ? Have you tried to play the movie with a 3D TV ?

Anyway, try to change the aspect ratio settings of your player. It should be possible to display the movie correctly, in 2D or 3D.

Also, can you open the movie in a good player, and ask for information about the video stream. With MPC, just select the Properties menu item. You should see something like this:
Video: MPEG4 Video (H264) 1920x2160 (16:9) 23.976fps [...]
With PotPlayer, select the Playback/System Info option, and look for the width and height fields in the File Info tab:
Width : 1 920 pixels
Height : 2 160 pixels
Note the resolution (in red). It's the correct resolution for Full-TAB. If you have the same resolution, that means almost certainly that the video is correct, and you have just to either change the aspect ratio and/or 3D settings of your player, or use a better player. (Personally, I recommend PotPlayer.)

Let me know if you need some help to configure your player.
Good luck!

[albur]

OK, I did some Full-TAB tests and everything works as expected, at least here.

But I've also played with the settings of the players, and I have managed to get something identical to what you have shown in your TAB screenshot above. So, now, I suspect that your player doesn't have the correct settings to play 3D movies with the correct aspect ratio.

What player do you use ? Have you tried to play the movie with a 3D TV ?

Anyway, try to change the aspect ratio settings of your player. It should be possible to display the movie correctly, in 2D or 3D.

Also, can you open the movie in a good player, and ask for information about the video stream. With MPC, just select the Properties menu item. You should see something like this:
Video: MPEG4 Video (H264) 1920x2160 (16:9) 23.976fps [...]
With PotPlayer, select the Playback/System Info option, and look for the width and height fields in the File Info tab:
Width : 1 920 pixels
Height : 2 160 pixels
Note the resolution (in red). It's the correct resolution for Full-TAB. If you have the same resolution, that means almost certainly that the video is correct, and you have just to either change the aspect ratio and/or 3D settings of your player, or use a better player. (Personally, I recommend PotPlayer.)

Let me know if you need some help to configure your player.
Good luck!

Thank you, i've tried in MPC-HC, VLC, PowerDVD and Kodi 18 Player, in everyone i get the same except PowerDVD that only shows 2D, i don't really know why.

I will pot player a try, could be that i have a 1080p Resolution and it cant show the image (2160p) keeping the aspect ratio?

[r0lZ]

I will pot player a try, could be that i have a 1080p Resolution and it cant show the image (2160p) keeping the aspect ratio?I don't think it's the problem. If the player can load the file and has enough RAM for its buffers, it should be able to display it with the right aspect ratio.

Note also that AFAIK MPC is not able to play 3D-video files. It's certainly not the right player to test your encodings. Pot Player can, but it is relatively difficult to configure. I don't use VLC, PowerDVD and Kodi, so I can't help to configure them.

BTW, there are also some settings related to the aspect ratio in BD3D2MK3D. It seems that the required aspect ratio when encoding in Full-SBS or Full-TAB is not always necessarily coherent for some TVs (notably LG). That problem is not present when you encode in Half-SBS or Half-TAB, but since you prefer the hard way, you may want to experiment with these settings too, although the software players are normally powerful enough to let the user change the aspect ratio manually.

[albur]

I don't think it's the problem. If the player can load the file and has enough RAM for its buffers, it should be able to display it with the right aspect ratio.

BTW, there are also some settings related to the aspect ratio in BD3D2MK3D. It seems that the required aspect ratio when encoding in Full-SBS or Full-TAB is not always necessarily coherent for some TVs (notably LG). That problem is not present when you encode in Half-SBS or Half-TAB, but since you prefer the hard way, you may want to experiment with these settings too, although the software players are normally powerful enough to let the user change the aspect ratio manually.


With potplayer by default it doesn't work, but in this one if i chage the ratio in the player to 16:9 it works. I will try in the projector.

Thx

[konikpolny]

r0lZ,
Regarding the Flat 3D problem, many thanks for your suggestions.
First, the machine in question is AMD, so not the intel issue. Second, my original Avisynth script was using FRIMSource as the decoder.
Now, the tests you suggested:
The results for FRIMSource with platform = "sw" are exactly the same as before.
However, the change to DGMVCSource decoder did fix the problem.
Note that as with FRIMSource the change in the mode between "auto" and "sw" did not make any difference.
Below the 4 configurations and results with DGMVCSource:
1a)
left = SelectEven(interleaved)
right = SelectOdd(interleaved)
StackHorizontal(Left, Right)
= inverted 3D

1b)
left = SelectEven(interleaved)
right = SelectOdd(interleaved)
StackHorizontal(Right, Left)
= correct 3D!

2a)
right = SelectEven(interleaved)
left = SelectOdd(interleaved)
StackHorizontal(Right, Left)
= inverted 3D

2b)
right = SelectEven(interleaved)
left = SelectOdd(interleaved)
StackHorizontal(Left, Right)
= correct 3D!

I recently had 3 of such BD3Ds, all animated titles: the Boss Baby, Shrek the Third, Epic.
Now I know it, I will look at each avisynth script before encoding but it would be good BD3D2MK3D pop up the message, or even change the script accordingly.
Many thanks again :thanks:

[r0lZ]

With potplayer by default it doesn't work, but in this one if i chage the ratio in the player to 16:9 it works. I will try in the projector.

ThxThat means at least that there are no black borders. What you have seen are borders around the picture, added by the player when you play the movie full-screen.

End of story. :-)

[r0lZ]

r0lZ,
Regarding the Flat 3D problem, many thanks for your suggestions.
First, the machine in question is AMD, so not the intel issue. Second, my original Avisynth script was using FRIMSource as the decoder.
Now, the tests you suggested:
The results for FRIMSource with platform = "sw" are exactly the same as before.
Note that as with FRIMSource the change in the mode between "auto" and "sw" did not make any difference.If you don't have a CPU compatible with the hardware acceleration, "auto" uses the software mode, and it is therefore exactly equivalent to "sw". And don't try to force "hw", as the script will crash. It's normal. Anyway, the hardware mode is not terribly efficient. Just a little bit faster, but it has also a lot of problems, due to the bugs in the Intel libraries. Personally, I'm happy with the software mode.


However, the change to DGMVCSource decoder did fix the problem. Good to know. Unfortunately, none of these decoders is perfect. I have already changed the default decoder (currently FRIMSource), but perhaps I will have to change it again. :-(

Below the 4 configurations and results with DGMVCSource:

[...]

2b)
right = SelectEven(interleaved)
left = SelectOdd(interleaved)
StackHorizontal(Left, Right)
= correct 3D!

I recently had 3 of such BD3Ds, all animated titles: the Boss Baby, Shrek the Third, Epic.
Now I know it, I will look at each avisynth script before encoding but it would be good BD3D2MK3D pop up the message, or even change the script accordingly.
Many thanks again :thanks:
The 2b script is the one that has been created by BD3D2MK3D, right? So, without the FRIMSource bug, BD3D2MK3D does its work correctly, right ? So, IMO, there is nothing to change in BD3D2MK3D. And I don't understand what you suggest. What message should I show ? Except explaining that in case of bug, it might be useful to try the other decoder, I can't do much more.

Of course, I will contact VideoFan3D, the author of FRIM, in the hope that he will be able to fix the bug. [EDIT] Done. See here (https://forum.doom9.org/showthread.php?p=1870049#post1870049).

[konikpolny]

The 2b script is the one that has been created by BD3D2MK3D, right? So, without the FRIMSource bug, BD3D2MK3D does its work correctly, right ? So, IMO, there is nothing to change in BD3D2MK3D. And I don't understand what you suggest. What message should I show ? Except explaining that in case of bug, it might be useful to try the other decoder, I can't do much more.


Yes, the 2b script is the one BD3D2MK3D created. I agree we can wait to see what the FRIM's author says and possibly for the bug to be fixed.

[albur]

That means at least that there are no black borders. What you have seen are borders around the picture, added by the player when you play the movie full-screen.

End of story. :-)

Thank you, ok at least it can be played changing aspec ratio, i will dig into the muxing. When i show info into potplayer it shows:

1920x2160 (1:1.13/1:1.13)

And in mph-hc
Width : 1 920 pixels
Height : 2 160 pixels
Display aspect ratio : 0.889

[r0lZ]

However this setting for me output identical 2 views - there is no 3D, the left and right views have exactly the same image/frame.
I did some tests here, and indeed, I can confirm that FRIM bug. It happens only when the two views are in the unusual order (AVC base view = right eye, MVC dependent view = left eye).

Note that you don't have to examine the AVS script to see the order of the views. In the first tab of BD3D2MK3D, you can see what eye is associated with the AVC and MVC streams. And anyway, currently, I suggest to select DGMVCSource anyway.

And I understand now what you have suggested. I could add a warning when FRIM is defined as the MVC decoder and the two views are inverted. However, I would prefer a fix from Videofan3D...

Thanks for having discovered and reported this important bug !

[r0lZ]

Thank you, ok at least it can be played changing aspec ratio, i will dig into the muxing. When i show info into potplayer it shows:

1920x2160 (1:1.13/1:1.13)

And in mph-hc
Width : 1 920 pixels
Height : 2 160 pixels
Display aspect ratio : 0.889

The sample aspect ratio is normally 1:1 for a 2D BD and the display aspect ratio must be 16:9. But things are more complicated for the 3D SBS or T&B movies, as there are two images stacked together. The question is therefore: should I specify the AR for a single image, or for the two at the same time ? It seems that the answer depends of the TV used to play the movie, hence the difficulty. It's why it's a setting in BD3D2MK3D.

However, when you play the movie on a PC with a software player, the aspect ratio on fhe MKV file can easily be overwritten by the user. That means that you can play the movie without problem with any good 3D player, regardless of the AR in the file. But if you want to play it on a TV, be sure to test what you really need before you encode your entire collection of 3D BDs!

[konikpolny]

Note that you don't have to examine the AVS script to see the order of the views. In the first tab of BD3D2MK3D, you can see what eye is associated with the AVC and MVC streams. And anyway, currently, I suggest to select DGMVCSource anyway.

Indeed I can :)
Thanks for the info

[r0lZ]

Videofan3D will fix the FRIMSource bug with the inverted views soon (https://forum.doom9.org/showthread.php?p=1870434#post1870434). When the update will be available, I'll release a new version of BD3D2MK3D...

[r0lZ]

OK, Videofan3D has released a new beta with a fixed FrimSource. He wants to integrate the new Intel libraries before releasing it officially, but I have tested the 32-bit DLL and it works as expected. So, if you want to test it too, or if you prefer FrimSource rather than DGMvcSource, you can download the package (https://forum.doom9.org/showthread.php?p=1871006#post1871006), extract FRIMSource32.dll, rename it FRIMSource.dll, and overwrite the original DLL in the BD3D2MK3D's toolset folder.

I will release the new version of BD3D2MK3D when the final version of FRIMSource will be available...

[albur]

The sample aspect ratio is normally 1:1 for a 2D BD and the display aspect ratio must be 16:9. But things are more complicated for the 3D SBS or T&B movies, as there are two images stacked together. The question is therefore: should I specify the AR for a single image, or for the two at the same time ? It seems that the answer depends of the TV used to play the movie, hence the difficulty. It's why it's a setting in BD3D2MK3D.

However, when you play the movie on a PC with a software player, the aspect ratio on fhe MKV file can easily be overwritten by the user. That means that you can play the movie without problem with any good 3D player, regardless of the AR in the file. But if you want to play it on a TV, be sure to test what you really need before you encode your entire collection of 3D BDs!

Ok, i've found my issue, the result file is 3840x1080p, players doesn't deal fine with it, that's why height is half of it's size. Changing it to 3840x2160p in mkvmerge works fine in all players. But... if i play this in a 1080p screen i'm getting the same that if i play in half sbs?

[r0lZ]

The official release of the new version of FRIMSource is not available yet, but I have decided to release this version (with the bugfix test release of FRIMSource) because I think that it is important to fix the bug of the bad views occurring with the BD with the inverted views (right view first) as soon as possible. So, here is v1.9.

It fixes also a few other minor bugs, and as usual, I have updated the third-party exe files.

v1.9 (May 5, 2019)
- Workaround for the libDcaDec error when converting audio from DTS-HD/MA due to a change in numbers of channels. (Fix for Incredibles 2)
- When available, the alias of the Power Plans set before and restored after the encoding is now used instead of the GUID. Thanks Frank!
- Little bugs fixed
- Updated the FRIMSource MVC decoder to the bugfix version 1.29_20190406. Thanks konikpolny!
- Updated x264 to the latest version (0.157.2969)
- Updated x265 to the latest version (3.0_Au+18)
- Updated Mkvtoolnix to the latest version (33.1.0 'Primrose')

Download: BD3D2MK3D.7z (http://download.videohelp.com/r0lZ/BD3D2AVS/BD3D2MK3D.7z)

[Spaded21]

This software is great and I find the SBS mkv files to be much better than the actual disc. There is no blur when watching the SBS files. I have converted 16 movies so far and almost all came out great. However there are 2 movies, Life of Pi and Edge of Tomorrow, that have no offset between the 2 halves. When I put the glasses on, it's combines the images, but it's only 2D. I ran Life of Pi through twice just to see if it was a bad conversion or something, but the results are the same. Has anyone had this issue before?

In any case, thank you r0lZ for this great software. I can finally import my 3D library into Plex and even add the Atmos tracks when available.

[konikpolny]

Hi Spaded21,
regarding your encodes resulting in 2D, check your __ENCODE_3D_MOVIE.avs file if the views are inverted:

# Current base view: right eye!
# The views are inverted: AVC stream = right view, MVC stream = left view.
right = SelectEven(interleaved)
left = SelectOdd(interleaved)

if that's the case it's probably the bug with FRIMSource MVC decoder to blame. I suggest downloading the latest version of BD3D2MK3D as it's got a newer version of this 3rd party library and have another go.

You can also read more about the bug quite recently reported
here (http://forum.doom9.org/showthread.php?p=1869965#post1869965) and here (http://forum.doom9.org/showthread.php?p=1870025#post1870025)

[Spaded21]

Hi Spaded21,
regarding your encodes resulting in 2D, check your __ENCODE_3D_MOVIE.avs file if the views are inverted:

# Current base view: right eye!
# The views are inverted: AVC stream = right view, MVC stream = left view.
right = SelectEven(interleaved)
left = SelectOdd(interleaved)

if that's the case it's probably the bug with FRIMSource MVC decoder to blame. I suggest downloading the latest version of BD3D2MK3D as it's got a newer version of this 3rd party library and have another go.

You can also read more about the bug quite recently reported
here (http://forum.doom9.org/showthread.php?p=1869965#post1869965) and here (http://forum.doom9.org/showthread.php?p=1870025#post1870025)

I just tried with the new version and this is what's in the .avs file


# Current base view: right eye!
# The views are inverted: AVC stream = right view, MVC stream = left view.
right = SelectEven(interleaved)
left = SelectOdd(interleaved)

# Build Side-by-Side stream
StackHorizontal(HorizontalReduceBy2(Left), HorizontalReduceBy2(Right))
AssumeFPS("ntsc_film")

Does that mean it's still incorrect?

I registered for this forum a week or so ago and had to wait at least 5 days to post. I guess I should have caught up on the thread before asking my question. Thanks again.

[konikpolny]

Does that mean it's still incorrect?


It's OK, provided you use the latest BD3D2MK3D version. The old version would not work with the inverted views as the FRIMSource MVC decoder used in the previous BD3D2MK3D version was buggy. With the old version 1.8 you could still use the alternative MVC decoder DGMVCSource. You can read about this solution in the recent posts (links in my previous post).

r0lZ has recently posted this new version with an updated FRIMSource MVC decoder.

[Spaded21]

It's OK, provided you use the latest BD3D2MK3D version. The old version would not work with the inverted views as the FRIMSource MVC decoder used in the previous BD3D2MK3D version was buggy. With the old version 1.8 you could still use the alternative MVC decoder DGMVCSource. You can read about this solution in the recent posts (links in my previous post).

r0lZ has recently posted this new version with an updated FRIMSource MVC decoder.

Thanks again for your help. I did read through them but some of it was over my head. It's starting to make sense to me though.

Edit: Just want to confirm it's working for me now. Life of Pi looks amazing in 3D!

[Spaded21]

I have another question. Currently, some movies require me to use the 3D sync invert option on my projector and some do not. I would prefer not to have to use it at all. Is there a setting I can change to prevent this? And is this something I can only do prior to encoding?

[konikpolny]

And is this something I can only do prior to encoding?
Yes this is the setting I mentioned earlier in the __ENCODE_3D_MOVIE.avs file with the inverted views.
This is something that can only be set before the encoding starts. BD3D2MK3D however recognises such inverted stream views and swaps them to get the proper left base view when it creates the project, so you should always be OK with BD3D2MK3D.

The bug in the FRIMSource MVC decoder was causing problems here resulting in flat 3D movie for movies with inverted views which BD3D2MK3D tried to correct.
Normally if you swap the views there you get the inverted 3D effect.

[konikpolny]

r0lZ,
When I convert SRT 2D to ASS 3D with the 2D guide file temp_2D.xml (grabbed from the project's png subs directory) vertical placement is made correctly according to the guide but for the horizontal positioning none of the subs is correctly taken from the guide. THis is something I observed a long time ago but didn't have time to let you know.
Could you please have a look at this when you have time.

Also, I think someone already asked a similar request in the past - It would be really great if there was a choice to select whether we want both horizontal and vertical guides to be used or selectively horizontal or vertical only.

What I really care about is some adjustment to the vertical placement. This could be done by forcing the manual "Bottom margin" setting, or some additional adjustment option which would be added to the guide's vertical value. Ideally having both of these options available would be useful, but forcing the "Bottom margin" setting seems more important.
The reason why I am asking for this is that, whenever I can, I place my subtitles some way down half below the bottom edge of the video to get the subtitles out of the picture as much as possible, but at the same time still making them easy for the eyes to read.

Is that something that you could do in future?

[dejoro]

Hello everyone,

I discovered this forum finally, such a forum that I had been looking for quite some time.

I converted a 3D Bluray 3D MVC with Makemkv and from there I enter it directly into BD3D2MK3D to create a 3D SBS Full HD of 3840x1080p but I can not read it. This is the first time I use BD3D2MK3D.

Reading it with MPC-HC I get a stretched tape genre 2.40 while my film is in original 16/9. I have 3D but the format is wrong.

So my question, is there a specific player to read this file from BD3D2MK3D or any player, MPC-HC, VLC or Potplayer can read it? Or changes in the settings to make?

I have a passive 3D system with 2 Epson Full HD projectors, a Geobox G-303, Omega filters in the projectors and Omega glasses.

I can not find a tutorial to use BD3D2MK3D correctly because given the number of parameters to enter, I am lost.

Could you put me on the trail of a tutorial?

Thanks for your help. Excuse me for my english translated with Google Translator.

Denis

[konikpolny]

Hi dejoro,


Reading it with MPC-HC I get a stretched tape genre 2.40 while my film is in original 16/9. I have 3D but the format is wrong.


When you play your 3D Full-SBS movie in MPC-HC on your PC before you display it on your projector, are your left and right images squeezed vertically/horizontally being distorted or do they have proper dimensions side-by-side full frame pictures but just smaller to fit in screen?

So my question, is there a specific player to read this file from BD3D2MK3D or any player, MPC-HC, VLC or Potplayer can read it? Or changes in the settings to make?
All the 3 can play 3D Full-SBS for your projector with appropriate settings made in the player

[r0lZ]

Sorry for replying so late. For whatever reason, I have not been noticed of the new posts in this forum. Luckily, konikpolny has replied to most questions, and I have just to add that I agree totally with what he wrote.

Thanks Spaded21 for your positive feedback. Much appreciated ! And welcome to the Doom 9 forums.

Yes, the last version fixes the problem of the flat 3D when converting a movie with the inverted views with the FRIM decoder. The bug is fixed in the new FRIM decoder, and has never been present with the DGMVCSource decoder. So, just be sure to use the latest version, with whatever decoder you prefer.

I have another question. Currently, some movies require me to use the 3D sync invert option on my projector and some do not. I would prefer not to have to use it at all. Is there a setting I can change to prevent this? And is this something I can only do prior to encoding?
As explained by konikpolny, BD3D2MK3D is smart enough to encode the movie with always the left view first, regardless of the order of the views in the original BD. Of course, if the info about the orders of the views in the BD is wrong, BD3D2MK3D will fail too, but AFAIK that case has happened only once, with an obscure Chinese movie.
So, I guess that you have to swap the views manually only when you play some original BDs (and that means that your equipment ignores the "left view first" flag, not a good point!), or you have played MKV files not created by BD3D2MK3D, or downloaded from YouTube or other sources. Currently, all movies converted with BD3D2MK3D should never need to manually invert the views. Again, konikpolny was right.

[r0lZ]

r0lZ,
When I convert SRT 2D to ASS 3D with the 2D guide file temp_2D.xml (grabbed from the project's png subs directory) vertical placement is made correctly according to the guide but for the horizontal positioning none of the subs is correctly taken from the guide. THis is something I observed a long time ago but didn't have time to let you know.
Could you please have a look at this when you have time.
Sure, but I wonder if the problem is not just due to the difference with the single and double-line subtitles. If the subtitle is on a single line in the guide and split on 2 lines in the SRT, the result will be a bit too low, because it will be globally centered around the centre of the guide's subtitle, and not above its baseline. The opposite gives of course the opposite effect. Of course, I can't fix that easily, because BD3D2MK3D knows only the "bounding box" of the subtitle of the guide, and not the position of its baseline. Furthermore, even with 2 subtitles sharing the same number of lines, the placement is not always perfect, because the font size may be different, and the subtitles may contain some letters with "extensions" above or below the normal letters, and the other subtitle not. This causes some little Y displacements, difficult to avoid completely.

I agree that a solution could be an option to force the Y position, and to grab the X position from the guide only. That cannot be forced anyway, as many subtitles are placed on screen at different heights (like in Avatar) to avoid entering in the objects of the foreground. Some other examples use subtitles always at the same Y position, except for some of them, that are placed above the image (in the sky). It's also something that must be handled.

Also, I think someone already asked a similar request in the past - It would be really great if there was a choice to select whether we want both horizontal and vertical guides to be used or selectively horizontal or vertical only.
I agree and I'll try to do it.

What I really care about is some adjustment to the vertical placement. This could be done by forcing the manual "Bottom margin" setting, or some additional adjustment option which would be added to the guide's vertical value. Ideally having both of these options available would be useful, but forcing the "Bottom margin" setting seems more important.
The reason why I am asking for this is that, whenever I can, I place my subtitles some way down half below the bottom edge of the video to get the subtitles out of the picture as much as possible, but at the same time still making them easy for the eyes to read.
I see, but what you do is dangerous. Often, the subtitle's depth is computed so that it appears just above the ground. If you place it below its normal position, chances are that it will enter in the ground. So, IMO, you should first analyse the guide, and force the Y position of all subtitles only if the analyse deduces that all subtitles are placed approximately at the same Y position, and to avoid problems, you should use that position, and not force them below (or above) that position.

Is that something that you could do in future?
I will have to analyse the problem of the wrong placement. If you have good examples of the first problem you have reported, please send me the guide (XML file only) and the SRT, and the number of one or two misplaced subtitles. It will be easier for me to fixd the bug, if any.

I can also add an option to "freeze" the X position on the center of the screen, and another to force the Y position to either the average Y position of the subtitles of the guide, or another Y position specified by the user. Perhaps also with an option to ignore that setting for all subtitles appearing in the upper half of the screen.

However, I'm going in holidays this weekend for 4 weeks, so don't expect that soon.

[r0lZ]

Hello everyone,

I discovered this forum finally, such a forum that I had been looking for quite some time.

I converted a 3D Bluray 3D MVC with Makemkv and from there I enter it directly into BD3D2MK3D to create a 3D SBS Full HD of 3840x1080p but I can not read it. This is the first time I use BD3D2MK3D.

Reading it with MPC-HC I get a stretched tape genre 2.40 while my film is in original 16/9. I have 3D but the format is wrong.

So my question, is there a specific player to read this file from BD3D2MK3D or any player, MPC-HC, VLC or Potplayer can read it? Or changes in the settings to make?

I have a passive 3D system with 2 Epson Full HD projectors, a Geobox G-303, Omega filters in the projectors and Omega glasses.

I can not find a tutorial to use BD3D2MK3D correctly because given the number of parameters to enter, I am lost.

Could you put me on the trail of a tutorial?

Thanks for your help. Excuse me for my english translated with Google Translator.

Denis
Welcome to the Doom 9 forums, dejoro !

You can probably use a player that can force the aspect ratio of the movie (like PotPlayer), but IMO it's not the right solution.

The problem with the SBS and TAB 3D movies is that the aspect ratio must be specified either for the whole image (with the 2 views), or for a single view (after the division to 2 equal views, and the required resize). It seems that it's not a problem with Half-SBS and Half-TAB, but for Full-SBS or Full-TAB, the de-facto standard is not well established. So, the right aspect ratio to include in the file depends of your 3D equipment. Furthermore, two different aspect ratios must be specified, one in the video stream, and one in the MKV header. Since I can't know in advance on what equipment the final MKV will be played, it is your responsibility to provide the right aspect ratios.

See the menu Settings -> Full-SBS/T&B aspect ratio. Change the two settings one at a time, and try to encode a short clip, to determine what combination works best with your equipment or software player. It's a pity, but I cannot help you more.

Note also that Full-SBS is a non-standard format. If you want to avoid most problems (with the aspect ratios or the 3D subtitles for example), I recommend to encode in Half-SBS. The price to pay is of course the half-resolution, but it's much more simple, and you will probably never have bad surprises, especially when you buy a new TV or video player.

[albesp77]

just a stupid question, if i generate a full sbs or full ou video files (instead of half ones) to see them on a fullhd tv that not support natively this format (works good on half files) which kind of external player i need ?

[konikpolny]

just a stupid question, if i generate a full sbs or full ou video files (instead of half ones) to see them on a fullhd tv that not support natively this format (works good on half files) which kind of external player i need ?

any player on PC will do: MPC-HC, VLC or Potplayer. For full-SBS / OU you just need to change video Aspect Ratio to 16:9

[donpoku]

Hi guys, I'm trying to MUX 3d ISO to m2ts, I keep getting this using BD3 work my laptop, I read here it could be a sleep mode problem but I have changed my battery settings to never sleep.
Here's the CMD report

Encoding movie in 3D
Movie: Captain Marvel (2019)
Encoding started 23/06/2019 18:12:18.93

C:\Users\.....\Documents\Captain Marvel (2019)\MKV3D>"D:\S\New folder\Recovered data 10-06 06_45_31\Deep Scan result\More Lost Files(RAW)\Rich Text Document\BD3D2MK3D (2)\BD3D2MK3D\toolset\x264_x86.exe" --output-depth 8 --crf 23 --preset medium --sar 2:1 --range tv --colormatrix bt709 --frame-packing 4 --qpfile chapters_3D.qpfile --frames 177957 --fps 24000/1001 --output "MKV3D_3D.264" "__ENCODE_3D_MOVIE.avs"
avs [error]: ERROR: Cannot initiate Intel Media Decoder.

(__ENCODE_3D_MOVIE.avs, line 20)
x264 [error]: could not open input file `__ENCODE_3D_MOVIE.avs'
Encoding finished 23/06/2019 18:12:19.44

C:\Users\....\Documents\Captain Marvel (2019)\MKV3D>"D:\S\New folder\Recovered data 10-06 06_45_31\Deep Scan result\More Lost Files(RAW)\Rich Text Document\BD3D2MK3D (2)\BD3D2MK3D\toolset\mkvmerge.exe" @__MUX_3D_OPTIONS.json | "D:\S\New folder\Recovered data 10-06 06_45_31\Deep Scan result\More Lost Files(RAW)\Rich Text Document\BD3D2MK3D (2)\BD3D2MK3D\toolset\tee.exe" "MKV3D_3D.mkvmerge.log"
mkvmerge v33.1.0 ('Primrose') 32-bit
Error: The type of file 'MKV3D_3D.264' could not be recognized.

[supa2001]

I have some interesting information to share after I tried a lot of different formats with my android TV. I wanted to use a native android app (in my case Movian) to play 3D content on the tv and since no external HDMI-connected-player is involved I cannot use the HDMI 1.4+ 1920x2205 frame-packing format. I had to chose from one of the HALF SBS/TAB formats, because I had some weird issues with the FULL SBS/TAB.

Anyway, my TV is Sony Bravia 4k 2015 (KD-55S8505C) with active 3D, running Android TV 7 and it supports H264/AVC Level 5.2 3840x2160 so I decided to encode 4K SBS :) which is 1920x2160 for each eye (vertically stretching each frame). During playback the TV stretches each frame to 3840x2160 (or shrinks it to 1920x1080) and this gives me back two full 1920x1080p frames in 3D. It is kind of a hybrid version of Half/Full SBS/TAB. :)


Anyone else able to do this on a Sony 3D TV?
I tried it, but my Sony Z9D won't play 3D for any film that has resolution greater than 1080p.
Sony's site says it also "An Android TV that supports 3D format
If you have a 4K TV, a 3D signal won't display if the TV receives a 4K signal."
https://www.sony.com/electronics/support/articles/00172421

Any idea how to get around this limitation?

[konikpolny]

Hi r0lZ,
I hope you had great holidays!

Regarding the X positioning from the guide problem:
Sure, but I wonder if the problem is not just due to the difference with the single and double-line subtitles.
By horizontal I mean X placement. The double/single lines difference does not apply here as it would only affect the Y plane, which works fine for me. What you are describing here is possible minor differences but for Y axis.
I also do the subtitles OCR myself. They have original number of lines and lines length.
I did check it carefully - selected subtitles position on original BD3D movie, the temp_2D.xml guide, and also studying the subtitles placement through your tool SRT 2D to ASS 3D > Analyse the subtitle Guide > BDSup2Sub. The latter clearly confirms the original BD guides have the correct position for the selected subtitles showing them at left / right sides rather than in the exact center X axis! And I don't mean here subtle differences they just come in the very center of X placement!


I see, but what you do is dangerous. Often, the subtitle's depth is computed so that it appears just above the ground. [...] So, IMO, you should first analyse the guide, and force the Y position of all subtitles only if the analyse deduces that all subtitles are placed approximately at the same Y position, and to avoid problems, you should use that position, and not force them below (or above) that position.
In extreme cases (which in my experience are rare) i can manually replace the lines in the subtitles with the ones with the original Y position. Also what you suggest for an option to ignore Y user custom position if sub lines are in the upper half would resolve most cases. I just don't like subtitles to be covering the video, pushing them slightly down works fine for me 90%. If the X guide worked it would be even better!


I can also add an option to "freeze" the X position on the center of the screen, and another to force the Y position to either the average Y position of the subtitles of the guide, or another Y position specified by the user. Perhaps also with an option to ignore that setting for all subtitles appearing in the upper half of the screen.
As i said earlier the Option to ignore forced user's Y placement setting if the subtitle appear in the upper half of the screen is a great idea indeed!

Locking X position in center in my opinion is not very useful as it would be more like not using guide at all - which is already an available option. But you can add it if you think having a user customised Y placement option implies doing the same for the X position.

Summing up the options for custom user Y positioning worth considering are:
- ignore guide completely and use user Y value (this is most important in my opinion)
- add/deduct user value to guide Y value
- average Y position

Please have a look at the XML guide and SRT attached;
some lines to look at:
#21:right,#25:left,#26:right,#39:right,#65:left,#77:left,#95:up center (OK),#126:right,#127:left,#128:right,#129:right,#130:right,#131:left,#138:left,#139:left,#664:left,#665:left,#666:left

[donpoku]

Hi guys, I'm trying to MUX 3d ISO to m2ts, I keep getting this using BD3 work my laptop, I read here it could be a sleep mode problem but I have changed my battery settings to never sleep.
Here's the CMD report

Encoding movie in 3D
Movie: Captain Marvel (2019)
Encoding started 23/06/2019 18:12:18.93

C:\Users\.....\Documents\Captain Marvel (2019)\MKV3D>"D:\S\New folder\Recovered data 10-06 06_45_31\Deep Scan result\More Lost Files(RAW)\Rich Text Document\BD3D2MK3D (2)\BD3D2MK3D\toolset\x264_x86.exe" --output-depth 8 --crf 23 --preset medium --sar 2:1 --range tv --colormatrix bt709 --frame-packing 4 --qpfile chapters_3D.qpfile --frames 177957 --fps 24000/1001 --output "MKV3D_3D.264" "__ENCODE_3D_MOVIE.avs"
avs [error]: ERROR: Cannot initiate Intel Media Decoder.

(__ENCODE_3D_MOVIE.avs, line 20)
x264 [error]: could not open input file `__ENCODE_3D_MOVIE.avs'
Encoding finished 23/06/2019 18:12:19.44

C:\Users\....\Documents\Captain Marvel (2019)\MKV3D>"D:\S\New folder\Recovered data 10-06 06_45_31\Deep Scan result\More Lost Files(RAW)\Rich Text Document\BD3D2MK3D (2)\BD3D2MK3D\toolset\mkvmerge.exe" @__MUX_3D_OPTIONS.json | "D:\S\New folder\Recovered data 10-06 06_45_31\Deep Scan result\More Lost Files(RAW)\Rich Text Document\BD3D2MK3D (2)\BD3D2MK3D\toolset\tee.exe" "MKV3D_3D.mkvmerge.log"
mkvmerge v33.1.0 ('Primrose') 32-bit
Error: The type of file 'MKV3D_3D.264' could not be recognized.

Is nobody able to help us, this is not what the community is about?

[r0lZ]

Sorry for replying so late. I was in holidays.

avs [error]: ERROR: Cannot initiate Intel Media Decoder.
This problem can be caused by several things, but normally, that means that you have an Intel CPU compatible with the hardware acceleration for the MVC decoding, but the Intel drivers do not work correctly. Try to update the Intel drivers, or re-install them. Then, launch __ENCODE_3D_LAUNCHER.cmd again.

If that doesn't work, try to set the Settings -> MVC Decoder -> Hardware Acceleration option to Disabled. This will use the Intel decoder provided with BD3D2MK3D, and normally it works correctly. Then re-generate the whole project. (Alternatively, you can also edit the platform argument of the FRIMSource line or the mode argument of the DGMVCSource line in the avisynth script __ENCODE_3D_MOVIE.avs, and replace "" or "auto" with "sw", as explained elsewhere in this thread. If you do that, you don't need to re-generate the project.)

And if there is still a problem, try to swap the decoder (Settings -> MVC Decoder: FRIMSource <-> DGMVCSource).

Good luck!

[r0lZ]

Hi r0lZ,
I hope you had great holidays!
Yes, fine, although very hot !

I will have a look at the subtitles placement problems, but I still need some time. I am currently seeking for a house to move in France, and I have to continue searching. So, don't expect a new version soon.

[EDIT] Just had a look, and it seems that indeed, the X position of all subs is always the center of the screen when the SRT is converted to ASS 3D with the Margins option. However, with the option "{\pos(x,y)} commands", it seems that the X placement is correct. Can you verify ?

[konikpolny]

Hi r0lZ,
Yes I confirm X placement in SRT 2 ASS conversion with the guide using {\pos(x,y)} works as expected! Thanks for this hint.
I am perfectly OK to wait for the SRT 2 ASS bug fix (X guide with margin method) and enhancements whatever time it takes to accomplish. Please take care and time to sort out all your private matters.

[donpoku]

Sorry for replying so late. I was in holidays.


This problem can be caused by several things, but normally, that means that you have an Intel CPU compatible with the hardware acceleration for the MVC decoding, but the Intel drivers do not work correctly. Try to update the Intel drivers, or re-install them. Then, launch __ENCODE_3D_LAUNCHER.cmd again.

If that doesn't work, try to set the Settings -> MVC Decoder -> Hardware Acceleration option to Disabled. This will use the Intel decoder provided with BD3D2MK3D, and normally it works correctly. Then re-generate the whole project. (Alternatively, you can also edit the platform argument of the FRIMSource line or the mode argument of the DGMVCSource line in the avisynth script __ENCODE_3D_MOVIE.avs, and replace "" or "auto" with "sw", as explained elsewhere in this thread. If you do that, you don't need to re-generate the project.)

And if there is still a problem, try to swap the decoder (Settings -> MVC Decoder: FRIMSource <-> DGMVCSource).

Good luck!
Thanks the first option worked.

What is the best setting for 1:1 copy with no loss in quality,?

[donpoku]

Hi yday I did one from 40gig disc to 7gb using this, surely there's a loss in quality? If so what's the best way to get like for like with no loss in quality?

Many thanks

[TVI]

Dear r0lZ. First of all thank you for your program it's fantastic. I do have a question.

I use BD3D2MK3D to convert ripped 3D Blu-Rays to watch on the Ocolus Go and it works a treat. I'm not particularly tech-savvy...I download the ripped MKV and don't change any of the settings.

The files will vary in size and quality. For example -
Terminator 2 - 7.22GB - Great picture
Gravity - 3.72GB - decent picture
Bladerunner 2049 - 1.63GB - okay picture but more "screen door" effect

I just wondered if there was a simple reason why the files vary in size/quality?

Thanks.

[tebasuna51]

I just wondered if there was a simple reason why the files vary in size/quality?

If you encode using CRF method you obtain the same quality always, but the size can vary because the images are more or less compressibles.

For instance Terminator 2 can have grain or noise and need more bitrate (size) than a modern movie Blade Runner 2049 (BTW 1.63 GB is very small, use a better CRF)

[mi3gai4rui4]

Hi,
I have a 4k OLED with a passive 3d filter that works with madVR set to "3D format: line alternative".

I'd like to convert from my 3d mvc file to an mkv file that is 3840x2160 in line alternative format so that I can play it on a player that doesn't know how to decode 3D at all and the TV will just play it like a regular 2160p file.

I tried following the directions below but I ended up with a 1920x1080 file.
Could anyone suggest how to get a 3840x2160 line alternative file?

Thanks!

@Shark: My PC doesn't have a 3D graphic card, so I suppose that options cannot be used. But thanks anyway.

@IanD:
I have modified the files of a short clip and I think I have something that should work. Can you test the modifications?
Use a short clip to begin (and, optionally, select the UltraFast x264 preset). Use T&B or SBS, that doesn't matter.
When the demux phase is finished, edit the following files.

_ENCODE_3D_MOVIE.avs:
You should replace the following lines:

left = SelectEven(interleaved)
right = SelectOdd(interleaved)

# Build combined Side-by-Side image
StackVertical(...) (or StackHorizontal)

with this:

left = SelectEven(interleaved).SeparateFields().SelectOdd()
right = SelectOdd(interleaved).SeparateFields().SelectEven()

# Build combined Row-interlaced image
Interleave(left, right).Weave()

The code above is for the left view in the top field. To place the right view in the top field, use this:

left = SelectEven(interleaved).SeparateFields().SelectEven()
right = SelectOdd(interleaved).SeparateFields().SelectOdd()

# Build combined Row-interlaced image
Interleave(right, left).Weave()

That should work, but I'm not sure. If you see inverted fields, experiment with the words in red above.

You should also modify _ENCODE.CMD and replace the option "--frame-packing 4" (or 3 for SBS) with "--frame-packing 2".

You should also edit the "3D Video stream" section of the _MUX_3D_OPTIONS.txt file, like this:

# 3D video stream

--track-name
0:3D Row interlaced (x264 CRF 22, preset ultrafast, level 4.1)
--stereo-mode
0:7
--aspect-ratio
0:16/9
--default-duration
0:24000/1001p
--default-track
0:yes
01000_mpls.264

The stereo mode 7 is for the left field on top. Use 6 for the right field on top.

When the edits are finished, encode normally, and watch the movie on your TV. Perhaps you'll see some flickering effects (especially with thin horizontal lines, or in the end credits). Please let me know if it's the case. It is perhaps possible to improve the image quality and avoid the flickering with a resize instead of the SeparateFields().SelectOdd/Even() code.

Let me know if it works fine. If your tests are conclusive, I may add that option in the next version...

[r0lZ]

Sorry again, for whatever reason, the forum do not send me the notifications for the new posts any more, hence my late replies.Hi yday I did one from 40gig disc to 7gb using this, surely there's a loss in quality? If so what's the best way to get like for like with no loss in quality?

Many thanks
When you re-encode a video file, there is always a loss in quality, except if you use specifically the lossless options. And re-encoding losslessly doesn't make much sense, as usually, the size of the final MKV file is greater than the original M2TS file ! So, the question is : what amount of loss of quality can I accept ? I can't reply for you, but usually, I consider that it's mainly a false problem. Of course, if you compress extremely, the quality loss will also be extreme, and therefore much visible, but most peoples cannot see the difference with the original BD (without using special tools) when the default option (CRF 23) is used. The decrease of the file size is NOT really an evidence of a visible quality loss, and it depends largely of the images of the original movie. Trust your eyes, and do not imagine that you can see a difference because you think that a small size means bad quality.

That being said, you can easily modify the quality (and the size) of the encoding. As noted by tebasuna51, the CRF mode is recommended, because it adapts itself so that you will always obtain more or less the same quality, but the file size may vary, especially for old films with much noise. The CRF parameter can be used to increase the quality and the file size. The default value for x264 (CRF 23) gives good results for a very small file size, but you can decrease it to, say, 20 or even 15 to obtain a much better quality, but take in mind that the file size of the video stream can be doubled when you decrease the CRF value by approximately 3.

BTW, to encode in lossless mode, use CRF 0, but buy a big hard disc, as you will obtain a huge file size !

[r0lZ]

Dear r0lZ. First of all thank you for your program it's fantastic. I do have a question.

I use BD3D2MK3D to convert ripped 3D Blu-Rays to watch on the Ocolus Go and it works a treat. I'm not particularly tech-savvy...I download the ripped MKV and don't change any of the settings.

The files will vary in size and quality. For example -
Terminator 2 - 7.22GB - Great picture
Gravity - 3.72GB - decent picture
Bladerunner 2049 - 1.63GB - okay picture but more "screen door" effect

I just wondered if there was a simple reason why the files vary in size/quality?

Thanks.
Thanks for your kind words.

As explained by tebasuna51, when you use the CRF encoding mode, the quality doesn't vary much, but the file size can vary, due to the difficulty to compress the images of the original movie. A CGI film like an animated Pixar movie can be compressed extremely well, because the image is very clean and without artifacts. In the other hand, old movies with much noise are very difficult to compress, because each frame is different from the previous one. So, differences in file size are not unusual, and you should not worry about them.

BTW, many peoples think that a specific bitrate is important to encode correctly, and prefer to encode in 2-pass mode for that reason, but it's totally wrong. Specifying the bitrate (in ABR or even 2-pass modes) imposes a constraint that the encoder must obey, and therefore, the quality is ALWAYS less good than the encoding in CRF mode (when it gives finally approximately the same file size, of course). The ONLY interest of 2-pass mode is therefore to control precisely the size of the final MKV file. That may be important if you need to copy it on a physical media like a DVD, but you should always avoid that mode if you don't care of the final file size.

See also my previous reply, just above this one.

[r0lZ]

Hi,
I have a 4k OLED with a passive 3d filter that works with madVR set to "3D format: line alternative".

I'd like to convert from my 3d mvc file to an mkv file that is 3840x2160 in line alternative format so that I can play it on a player that doesn't know how to decode 3D at all and the TV will just play it like a regular 2160p file.

I tried following the directions below but I ended up with a 1920x1080 file.
Could anyone suggest how to get a 3840x2160 line alternative file?

Thanks!
Unfortunately, it's not possible, at least automatically with BD3D2MK3D (and honestly, I don't think that other software exist to do what you want). Although line alternative is effectively a 3D format that exists officially, it is almost never used, and therefore I don't think someone will implement it.

IMO, for you, the best solution would be to buy a player that can convert SBS or TAB movies to line alternate. Not sure if they are easy to find.

However, you have revived an old post I wrote for someone having a similar question. I don't remember if he has replied that the method works, but I encourage you to try it.

I can't test the method right now, but try this:

left = SelectEven(interleaved)
right = SelectOdd(interleaved)

# Build combined Row-interlaced image
Interleave(left, right).Weave()
This will (probably!) produce a line alternative 1920x2160 stream. To be verified!

BTW, I don't understand why you want a "3840x2160 line alternative file". In line alternative mode, the lines of the two images are stacked together, one at a time. Therefore, the height of the final image is doubled. But the width doesn't change, since there is no need to duplicate each pixel horizontally. So, IMO, the final format must be 1920x2160. If you really need a 3840x2160 frame, you must add a resize operation in the modified AVS script, like this:

left = SelectEven(interleaved).LanczosResize(3840,1080)
right = SelectOdd(interleaved).LanczosResize(3840,1080)

# Build combined Row-interlaced image
Interleave(left, right).Weave()
Please let me know if one of these methods worked for you. Thanks in advance!

[r0lZ]

Hi r0lZ,
Yes I confirm X placement in SRT 2 ASS conversion with the guide using {\pos(x,y)} works as expected! Thanks for this hint.
I am perfectly OK to wait for the SRT 2 ASS bug fix (X guide with margin method) and enhancements whatever time it takes to accomplish. Please take care and time to sort out all your private matters.
I have a beta to test. I think I've fixed the X placement bug and I have implemented the option to ignore the Y placement from the guide, and use the bottom margin instead. There is also the possibility to still use the guide for the vertical positions of the subtitles appearing in the upper half of the screen. I have not implemented the idea to add a certain amount of pixels to the Y position of the guide, as IMO, it doesn't make much sense. Either you want all subtitles properly aligned near the bottom of the screen, or you use the position from the guide because it is supposed to be the best placement according to the foreground objects in the scene. OK ?

You can download the SRTtoASS3D.tcl file here (http://download.videohelp.com/r0lZ/BD3D2AVS/SRTtoASS3D_v0.6.7z). Just replace the original file in the toolset folder with the file from the archive, and restart BD3D2MK3D. Please test it carefully, and let me know if it works correctly. If it's the case, it will be integrated in the next official version...

[donpoku]

Sorry again, for whatever reason, the forum do not send me the notifications for the new posts any more, hence my late replies.
When you re-encode a video file, there is always a loss in quality, except if you use specifically the lossless options. And re-encoding losslessly doesn't make much sense, as usually, the size of the final MKV file is greater than the original M2TS file ! So, the question is : what amount of loss of quality can I accept ? I can't reply for you, but usually, I consider that it's mainly a false problem. Of course, if you compress extremely, the quality loss will also be extreme, and therefore much visible, but most peoples cannot see the difference with the original BD (without using special tools) when the default option (CRF 23) is used. The decrease of the file size is NOT really an evidence of a visible quality loss, and it depends largely of the images of the original movie. Trust your eyes, and do not imagine that you can see a difference because you think that a small size means bad quality.

That being said, you can easily modify the quality (and the size) of the encoding. As noted by tebasuna51, the CRF mode is recommended, because it adapts itself so that you will always obtain more or less the same quality, but the file size may vary, especially for old films with much noise. The CRF parameter can be used to increase the quality and the file size. The default value for x264 (CRF 23) gives good results for a very small file size, but you can decrease it to, say, 20 or even 15 to obtain a much better quality, but take in mind that the file size of the video stream can be doubled when you decrease the CRF value by approximately 3.

BTW, to encode in lossless mode, use CRF 0, but buy a big hard disc, as you will obtain a huge file size !

Thank you for the response I'll give it a try. Bless.

[mi3gai4rui4]

Unfortunately, it's not possible, at least automatically with BD3D2MK3D (and honestly, I don't think that other software exist to do what you want).


I wouldn't mind editing the files output by BD3D2MKV3D, and I appreciate you trying to help.


BTW, I don't understand why you want a "3840x2160 line alternative file".

I was thinking I wanted to reproduce the output of madVR in line alternative format, which I believe is a 3840x2160 image. I suppose if the player respects the aspect ratio metadata then a 1920x2160 file should work, and will definitely be faster to encode and smaller on disk.

Using this code you suggested didn't work:

left = SelectEven(interleaved)
right = SelectOdd(interleaved)

# Build combined Row-interlaced image
Interleave(left, right).Weave()

I got an error saying the fields needed to be separated.
So I changed to:

left = SelectEven(interleaved).SeparateFields()
right = SelectOdd(interleaved).SeparateFields()

# Build combined Row-interlaced image
Interleave(left, right).Weave()


With this in MUX_3D_OPTIONS.json:

"--track-name",
"0:3D Row interlaced (x264 high CRF 23 preset superfast)",
"--stereo-mode",
"0:7",


This resulted in a 3840x1080 file.
Any thoughts on what needs to change to get a 1920x2160 file?

[konikpolny]

I have a beta to test. I think I've fixed the X placement bug and I have implemented the option to ignore the Y placement from the guide, and use the bottom margin instead. [...] Please test it carefully, and let me know if it works correctly.

Thanks r0lZ, for this quick update
I have done a quick test without using my 3D projector.
The guide's X placement for margin method moves the subtitles correctly but of the 2 (left+right) subtitle lines the right subtitle line has a very narrow margin and appears in the left view. As it has a very narrow margin the subtitle is spread from top to bottom word by word. This needs fixing.

As far as overriding Y guide with user bottom margin setting the results seem OK for both methods (with and without exception to the rule for subtitles appearing in the upper part of screen).