Questions about PGS and ASS subs (changing position and alpha level) [Archive]

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Mounter81

27th September 2020, 11:02

Hello!

I have a few different question, in hope that some may able to answer here:

PGS sup:

Is there a way to be able to change the subtitle position (vertically mostly) of PGS sup's in MPCHC? Tried with "Position override" but it's not working with (external) PGS subs.

Could be hotkeys programmed for vertical (up/down) subtitle position changing in MPCHC somehow? I have run through the Options->Keys section, but there's no entry regarding.

Maybe some of the above with using some kind of external filter or third party program?

ASS and SSA:

Is there a subtitle editor program, or any other way to add and change 'Alpha level" parameter for these subtitles? I guess SSA files have the value of "Alpha", but it's missing from (the more advanced) ASS?

Thanks!

jlw_4049

27th September 2020, 15:16

Mounter81

27th September 2020, 15:51

Check out SubtitleEdit

Sent from my SM-G986U1 using Tapatalk

Sorry, but you have may quite misunderstand my questions. I know SubtitleEdit, I use it frequently to create PGS subtitles and that has nothing to do with that after how can, or cannot these be positioned in MPCHC during playback. I also know it's ASS and SSA creator part and no such an option regrading the Alpha settings is present within at all.

jlw_4049

27th September 2020, 16:10

Yes. I'll Google and look around shortly.

Sent from my SM-G986U1 using Tapatalk

Mounter81

28th September 2020, 11:54

BTW, I have googled a lot regarding these questions and could not find any even nearly relevant info.
So still waiting for...

Nikse555

28th September 2020, 13:34

About ASS and SSA:
As far as I know ASS supports alpha channel (opacity), and the older SSA does not.
Be sure to set alpha for both "Primary", "Outline" and "Shadow" - is possible in SE (and surely also in Aegi Sub)

https://www.nikse.dk/se-assa-tr.png

Mounter81

10th October 2020, 11:20

The main reason I want to use ASS instead of PGS, because it's much faster and uses much less space.
This is my PGS preset that i want to achieve also with ASS:
https://i.imgur.com/ZoVmgfm.png

And this is how it looks currently with ASS:
https://i.imgur.com/VmdyxGD.png

If you enlarge the images, than you can obviously see that the PGS has some more kind of "smoothness" in the shadows (and overall just looks more soft and pleasant), while the ASS shadows are plain black and rough on the edges. And changing the Alpha level of the shadows in SubEdit doesn't seem to affect the shadow smoothness at all or anything. As if it weren't working at al.

So what's the catch here?

Thanks!

mbcd

10th October 2020, 11:52

You compare two different types of subtitle.
PGS is basically a bitmap, while ASS is text.

Subtitle position of PGS is hardcoded into the stream, most players cant change this position while playback.
The color difference in black is because SubtitleEdit uses correct colorspace to generate the bitmaps. Black on TV is not the same black as on PC, because of its different levels.
I guess ASS-Station does not do the correct levels for TV.

Changing alpha in SubtitleEdit-Shadows does make a difference at my version.

Mounter81

10th October 2020, 13:36

The difference I made in the Shadows Alpha only visible after I've saved and loaded the subtitle with playback via video, and not at all in the SubEdit's Text box. ???

Also very confusing and cumbersome, that the font sizes of the ASS are hugely different for the same font type compared to PGS. For FHD videos I use 54 for PGS and that's equals to 16 for ASS (comparing them during video playback) and with that setting it's impossible to relevantly edit or fine-tune the ASS style as it appears so tiny in the text box:
https://i.imgur.com/Puy0mTs.png

So I can only see the changes I've made after loaded and played back via video.

I guess I will report these for the "maker" on Github...

mbcd

10th October 2020, 18:27

The difference I made in the Shadows Alpha only visible after I've saved and loaded the subtitle with playback via video, and not at all in the SubEdit's Text box. ???

In my version I can see the difference directly at preview, before I hit start to create the subtitle-file. I speak about SubtitleEdit and its actual version.

This is explicit preview with its colored background.
https://www.bildhost.com/images/2020/10/10/Alpha.png

Personally I dont have much knowledge about ASS, but with textsubtitle most player have a setting for the fontsize, so it depends which player you use for playback. Some players may use the defined fontsize included in the subtitle-file (if they have), and some might ignore them and use their own playersettings.

PGS with SubtitleEdit is accurat, what you see at preview is what you get at playback.

Preview with ASS is useless, fontsize is not changing at mine too, so this might be a bug in SubtitleEdit. I guess there is no preview for ASS, its still the unformated player-default-preview, you still have no realtime PGS-Preview too.

Mounter81

11th October 2020, 03:44

The preview is fine for PGS in SubEdit, I can see every changes I've made and the Font size is also fine for that. But not at all for ASS, the fine-tuning Alpha level changes aren't displayed correctly, but it's also impossible to see any of the changes with this tiny font size in the preview window anyway.

von Suppé

11th October 2020, 09:53

...changing the Alpha level of the shadows in SubEdit doesn't seem to affect the shadow smoothness at all or anything. As if it weren't working at al.
I think changing shadow alpha channel works.
Watch the checkered box in the "Choose color" box while you move the "Alpha" pointer. You can see the effect, but it is not directly shown in the text.

Mounter81

11th October 2020, 10:03

I think changing shadow alpha channel works.
Watch the checkered box in the "Choose color" box while you move the "Alpha" pointer. You can see the effect, but it is not directly shown in the text.

Yes, I have also wrote this in my previous post. So the difficulty here is the later, that it can't be checked in the preview Box, so it's an almost absolutely blind tipping, that how it would look actually.

Have tried AiegiSub, but it has the same deficiency with the font size of the text shown in the preview window as SubEdit.

Anyone knows another Editor program for ASS to try that doesn't have these problems with the preview option?