Why is Plex identifying SD video as 576p?

General Discussions
21

@Elijah_Baley said:
I, too, do not see why this matters. If Plex plays the media correctly then what it says about the media is ultimately meaningless. I watch media I do not obsess over it.

I agree that it doesn’t matter with respect to playback but it does matter. First, it’s incorrect. When users are presented with data they know are incorrect they begin to lose trust in the application. If you want a real world use case, how about this:

I’m looking for a list of movies I ripped from DVD because I’m considering buying a blu ray version to replace it. My instinct would be to search for 480p videos since they are encoded as 480p. If I do that I won’t find any. Instead I have to know to go look under 576p. Now, if I didn’t know about this bug, why would I know to do that? I’d be confused as to why my videos weren’t showing up. If I then went looking for a specific video I already knew was 480p and saw it as 576p I’d wonder what was going on. Is my database messed up? Is Plex misinterpreting my content? Is something else going on?

Ultimately, plex is getting it wrong and while perhaps it isn’t the most severe bug it is a very visible one and so deserves some attention, especially since it is a regression. Plex used to get this correct.

22

@ac4lt said: …
Ultimately, plex is getting it wrong and while perhaps it isn’t the most severe bug it is a very visible one and so deserves some attention, especially since it is a regression. Plex used to get this correct.

I do not agree that it is “very visible.” Rather it is “invisible.” It only becomes visible if you actually look for it and i do not.

If a movie/TV show looks good to me that is good enough. If it does not look good then I either re-encode it or acquire another copy. I only even look at the resolution Plex, or any other agency, reports if there is a problem and, even then, I rarely look at the resolution but rather I am looking at other things that might cause an actual problem.

Others are perfectly welcome to use Plex’s reporting about their videos any way they wish and, if it is an easy fix, Plex should fix it. However if it involves any real amount of time on the part of the developers to fix then the should not bother as there are many, much more important from an operational stand point, issues that exist in the Plexiverse and those should be addressed well before any basically cosmetic issues are addressed.

Importance is always personal but I really fail to see how mis-reporting resolutions is in any way truly important in Plex’s overall scheme.

23

Broadcast standards have been in place for a long time for what 480i/p and 576 i/p must be. 480 = 704x480 or 720x480, and 576 is 704x576 or 720x576. Anything other than those resolutions do not meet the broadcast standard - and that’s what we’re talking about, right? Plex should stick with the standards for all of the broadcast resolutions (480/720/1080), and if media doesn’t fall into the standard it doesn’t get the cute little icon - just put the dimensions there instead.

24

Respectfully, @Elijah_Baley, you seem to be arguing that because it isn’t important to you then it isn’t important to others. I, for one, do find it important.

25

@ac4lt said:
Respectfully, @Elijah_Baley, you seem to be arguing that because it isn’t important to you then it isn’t important to others. I, for one, do find it important.

And you are arguing that because it is important to you then it must be important to everyone else. That is exactly what people do on forums like this. Present their views in the best way possible and as politely as possible. (For the most part when forums are at their best.)

I am saying that I believe it is unimportant to most people and therefore no special effort should be expended.

However this argument is less than moot due to the fact that Plex does not listen to users unless the the users agree with what Plex wants.

To be clear this functionality would not impact me one way or the other. My only real objection is that I do not see the value of knowing exactly what resolution a video is in. For me it either looks good or it does not and the details are meaningless.

Could I be wrong or could you be wrong? Of course it could even be that in many ways we are both wrong.

But regardless of my opinion or yours or anybody’s if they don’t work for Plex then Plex will ignore them so the only important view is that of Plex and it appears that Plex system is doing exactly what Plex wants it to do.

26

@Elijah_Baley said:
But regardless of my opinion or yours or anybody’s if they don’t work for Plex then Plex will ignore them so the only important view is that of Plex and it appears that Plex system is doing exactly what Plex wants it to do.

Unfortunately, that statement is the awful truth.

There are basically two user groups generally comprised of:

  1. Users that don’t really care what Plex does, so long as when the Play button is pressed something plays.
    and
  2. Users that wish Plex would pay more attention to details.

Of those there are two subsets:
a) Plex Passers
b) Non-Plex Passers

More from subset ‘b’ would gleefully move to subset ‘a’ if Plex would do #2 (which is what a lot of users feel Plex is already doing to users in general).

Plex, demonstrated by their actions, doesn’t seem too concerned about growing the ‘a’ subset by doing #2 which is a very strange business model and isn’t very good for Plex or any users.

27

@MovieFan.Plex said:
When US DVD movies started using widescreen, 720x480 was created, along with a new EDTV category but didn’t specify if this should be considered 480p (to fit the vertical resolution) or 576p (to fit the horizontal). So which box would you put this in? Plex chose to keep 640x480 for 480p and 768x576 for 576p, so this video fits into the 576p category.

576p and 480p refer to vertical resolution, full stop. There’s no misunderstanding at all. Even wikipedia reports “The 480 denotes a vertical resolution of 480 pixels, usually with a horizontal resolution of 640 pixels and 4:3 aspect ratio (480 ×  4⁄3 = 640) or a horizontal resolution of 854 or less (848 should be used for mod16 compatibility)[1] pixels for an approximate 16:9 aspect ratio (480 ×  16⁄9 = 853.3).”

The same argument can be made for extremely high aspect ratio videos such as 1920x720.

No, it’s not the same: 1920x720 is crearly a cropped 1080p frame. 1080p is not anamorphic (while 480p can be) and that 1920x720 is just a 1920x1080 cropped of black bars.

To be more precise, 480p and 576p should be used only for video that retains the full TV or DVD frame, black bars included. A 16:9 anamorphic DVD, for example, has a full picture of 720x576 pixels that is stretched to 16:9. If the movie displayed is 1.85:1 it will have hard black bars in the frame. If you encode this cropping black bars, although the data is basically the same it is incorrect to call it 576p because it’s nothing like that, it’s another resolution, although equivalent. 576p is a “standard” and anything not adhering to the standard should not be called 576p. So if I hard stretch a 720x576 frame from a 16:9 DVD to have it in non anamorphic resolution, that’s not 576p anymore.

28

@MovieFan.Plex said:
What if someone took a PAL DVD and cropped it to 480 vertical lines but kept the horizontal, so you got a 768x480 video?

That’s not 576p anymore. Simple. If you crop the frame, even to remove black bars, or if you stretch the frame, even to remove anamorphic, that’s not 576p anymore.

29

I’d say Plex should use “standards” naming like 720p, 1080p, 576p, 480p for what is completely adhering to the standard, that is the picture resolution and output aspect ratio (eventually anamorphic) are compliant with the specs of the standard. For all other options, including hard stretched anamorphic, cropped etc there are “generic” names like “SD”, “HD”, or simply list the resolution.

Another approach, more forgiving, is to reconstruct the “story” of the rip, don’t tell me it’s complicated because it’s not. Just take the actual resolution and the output aspect ratio and you can easily tell what the original format was and if the overall resolution of the standard has been respected or not.

30

@zpaolo11x said:
To be more precise, 480p and 576p should be used only for video that retains the full TV or DVD frame, black bars included. A 16:9 anamorphic DVD, for example, has a full picture of 720x576 pixels that is stretched to 16:9. If the movie displayed is 1.85:1 it will have hard black bars in the frame. If you encode this cropping black bars, although the data is basically the same it is incorrect to call it 576p because it’s nothing like that, it’s another resolution, although equivalent. 576p is a “standard” and anything not adhering to the standard should not be called 576p. So if I hard stretch a 720x576 frame from a 16:9 DVD to have it in non anamorphic resolution, that’s not 576p anymore.

Actually, that is not entirely correct:
https://forums.plex.tv/discussion/comment/1335697/#Comment_1335697

480p and 576p do describe the vertical resolution. The Former NTSC, the Latter PAL.

Correctly encoded NTSC DVD material always has a ‘Storage’ resolution of either 720x480 (Disc) or 704x480 (Mostly Broadcast). Proper Anamorphic settings tell the player how to display this content during playback. Cropping during a proper encode plays no part in it’s ‘Storage’. Widescreen ‘Letterboxed’ material will still be stored at one of the base ‘Storage’ resolutions described above as will properly encoded 4:3 material. It’s all properly ‘Stored’ as above. Properly encoded 4:3 material will have a ‘Display Width’ setting of 640p resulting in a final displayed resolution during playback of 640x480. 640x480 can be hard set without Anamorphic Width settings, but a Commercially Produced DVD will Store 640x480 at 720x480 and tell the player what to do with it when it’s displayed. Properly encoded 16:9 (for your standard NTSC widescreen display) will have a Width setting of 854. Cropping sets the ultimate vertical resolution during playback, but generally a full 16:9 properly encoded item will display at 854x480 and will fill a 16:9 display. Plex can’t read this ‘ultimate’ displayed resolution - I get that. Plex can only look at the ‘Storage’ res during it’s inspection when it’s identified. That is correct and proper. It’s how it’s always worked - until recently.

Correctly encoded PAL DVD material is stored at 720x576 (Disc) or, I assume 704x576 (Broadcast). I’ll admit to not knowing a lot about PAL and even less about what’s pumped into the air, but that’s not important right now. For PAL a properly encoded item at 16:9 will have a Width setting of 1024 resulting in a final displayed resolution of 1024x576 filling a 16:9 display. Again, Plex can’t extrapolate this final displayed resolution during inspection - but it doesn’t have to - it need only look at the Stored resolution to determine what it is.

DVD material for both PAL and NTSC should correctly be ‘Stored’ at one of the base resolutions described above and encoded with proper Anamorphic Width settings also described above for the proper final displayed resolutions - that Plex can’t determine on it’s brief initial inspection. It doesn’t have to. Properly encoded material is always Stored at one of it’s two possible Storage resolutions and it’s flat easy for Plex to see what that is and correctly report it.

In Handbrake, for instance, if you look at a ‘Static Preview’ of a Stored Frame it’s going to look all out of whack because you are looking at the ‘Stored’ resolution - not the final displayed image that’s only visible while the player is dealing with it displaying it on your screen. If you do some serious cropping for Widescreen Letterbox it’s REALLY going to look out of whack in a Static Preview, but that doesn’t matter. You’re only looking at the Static Preview to crop out the black stuff. All normal. Don’t give it another thought.

Every player on Earth knows how to deal with Anamorphic settings for DVD material because it’s the Industry Standard - in use for Decades and will be in use until DVDs are abolished… about the time the Sun eats the Earth I imagine.

I think what is happening is the Plex Developers are trying to ‘Overthink’ this whole thing - messing it up for everybody, but mostly for NTSC peeps who really got the ‘dirty’ end of the stick because Plex decided to call all properly Stored resolutions 576p and that’s just wrong.

31

@JuiceWSA said:
480p and 576p do describe the vertical resolution. The Former NTSC, the Latter PAL.

Correctly encoded NTSC DVD material always has a ‘Storage’ resolution of either 720x480 (Disc) or 704x480 (Mostly Broadcast). Proper Anamorphic settings tell the player how to display this content during playback. Cropping during a proper encode plays no part in it’s ‘Storage’. Widescreen ‘Letterboxed’ material will still be stored at one of the base ‘Storage’ resolutions described above as will properly encoded 4:3 material.

Yes but AFAIK the anamorphic setting is only to switch between 4:3 and 16:9, I might be wrong but, on DVD for example, a 1.85:1 movie is encoded in a 720x576 frame with balck bars that, once expanded to 16:9 to fill the TV screen, leaves the movie at 1.85:1 aspect ratio. I don’t think you can have a 720x576 frame expanded to 1.85:1 directly, at least on DVD, because the basics of the format are that you’re going to use a 16:9 or 4:3 TV with 576 lines.

but generally a full 16:9 properly encoded item will display at 854x480 and will fill a 16:9 display. Plex can’t read this ‘ultimate’ displayed resolution - I get that. Plex can only look at the ‘Storage’ res during it’s inspection when it’s identified. That is correct and proper. It’s how it’s always worked - until recently.

I’m not sure Plex can’t read that: I have a DVD rip which is 720x576 anamorphic and the info box in Plex shows the correct 16:9 aspect ratio, so Plex already has a way to tell the “display” AR. Of course it can’t tell the AR when black bars are hard coded in the frame data. But that’s not a problem: a whatever x 576 pixel frame with a display aspect ratio of 16:9 is 576p even if it has black bars.

I think what is happening is the Plex Developers are trying to ‘Overthink’ this whole thing - messing it up for everybody, but mostly for NTSC peeps who really got the ‘dirty’ end of the stick because Plex decided to call all properly Stored resolutions 576p and that’s just wrong.

I think the developers are reasoning more like computer geeks than TV geeks. A TV geek knows that the hard number, the only number that matter is VERTICAL resolution, because at the times of CRT you could not change it in any way, while horizontal resolution is “stretchable” in the analog realm :slight_smile:

32

@jjrjr1 said:
Anyone tell me why I should care about this in the real world and or usability of Plex??

Absolutely no reason whatsoever.
On the other hand I have no media with such low resolutions either so it will never be a problem for me.

33

@Elijah_Baley said:

@ac4lt said:
Respectfully, @Elijah_Baley, you seem to be arguing that because it isn’t important to you then it isn’t important to others. I, for one, do find it important.

And you are arguing that because it is important to you then it must be important to everyone else. That is exactly what people do on forums like this. Present their views in the best way possible and as politely as possible. (For the most part when forums are at their best.)

I am saying that I believe it is unimportant to most people and therefore no special effort should be expended.

I was simply trying to counter the argument that it was unimportant to most people by giving the point of view of one who does care about the bug.

34

My original post was regarding a video encoded at 720 X 404. It’s a pretty common resolution meant for a 16:9 display, at what I would consider SD or 480p.

It’s a simple, straight forward reduction in size, from a 1280 X 720 video encoded at ridiculously low rates for one user I share with who has the world’s slowest internet connection. I like to avoid on-the-fly transcoding whenever possible, even though the server is more than capable of doing so.

Since the original video does not have the anamorphic flag set, I don’t see the need to encode it as a 16:9 DVD rip at 720 X 480 and set the anamorphic flag so it displays correctly. I don’t use the “optimize” feature of Plex, but I can’t imagine it would convert the video using the anamorphic flag on a simple conversion like this.

As I stated originally, this particular resolution (720 X 404) used to be reported as SD. It made sense to me - the vertical resolution wasn’t quite 480p, definitely not 576p, but the horizontal resolution of 720 fit into both NTSC and PAL standards for the old 4:3 standard definition displays.

I was surprised that all of a sudden all of the SD versions had been “up-graded” (as @JuiceWSA said) to 576p. That’s a big jump from SD, leap-frogging over 480p, up to 576p.

I’m not losing too much sleep over this mis-reporting of resolutions, but the old method seemed somewhat more accurate as far as I’m concerned. Since I live in the NTSC part of the world, I don’t know how the old method effected PAL users, but I’m pretty sure my original example is SD no matter where you live.

Just my 2 cents worth…

35

I don´t understand this discussion!?
If I purchase a black Car then I want a black Car and not a Grey one!
It is like a Quality Thing to me. Do Things the right way and not half right, half wrong!
This is wrong. Fullstop. No discussion about it if someone care or it will effect someone. Wrong is wrong and Need a correction.
Case Close.

36

@zpaolo11x said:
Yes but AFAIK the anamorphic setting is only to switch between 4:3 and 16:9, I might be wrong but, on DVD for example, a 1.85:1 movie is encoded in a 720x576 frame with balck bars that, once expanded to 16:9 to fill the TV screen, leaves the movie at 1.85:1 aspect ratio. I don’t think you can have a 720x576 frame expanded to 1.85:1 directly, at least on DVD, because the basics of the format are that you’re going to use a 16:9 or 4:3 TV with 576 lines.

Nope. Even if you crop out the black bars the item will still be stored at 720x576. Cropping determines the final vertical display resolution the player will dutifully display, for widescreen letterbox and 4:3 providing you use a correct ‘Width’ setting, but no matter what you do the item will still be stored at 720x576. 4:3 material is also stored at 720x576. A proper Anamorphic ‘Width’ setting for 4:3 will be - I think - 768 resulting in the final displayed resolution of 768x576. If I lived in PAL-Land I would know what a 4:3 image should be, but I do not. Anamorphic was invented when 16:9 displays came around, but DVDs can’t hold the full resolution - so an Industry Wide Work Around was invented. That is now the Industry Standard On Planet Earth. That’s the long and the short of it.

BluRay discs can store the full sized material so no Anamorphic is required. DVDs can only hold 720x480 or 720x576. 720 being the limiting number.

It’s complicated - until you get your head wrapped around it.

Hopefully, Plex is now trying to get their head wrapped around it - or continue spinning in circles like a puppy with duct tape on it’s tail and just call everything 576p for the easy way out.

37

Somehow, the intent of my original post, which was “Why is Plex identifying SD video as 576p?” has been slightly sidetracked. Don’t get me wrong, the discussion is definitely interesting.

What I really wanted to know was, why has the video resolutions that Plex use to report as “SD” been removed.

Here’s a screen shot of the “Get info” content from a server that is shared with me. Obviously not upgraded to the new method because it shows the Video resolution as SD with a 720 X 400 resolution.

Identified correctly, I think, as an SD video. Not 480p. Not 576p.

Here is a BluRay rip I made a couple of days ago, intended to be an SD version, black bars cropped to 720 X 306 resolution. The vertical resolution is 270 pixels away from being 576p, but that’s how Plex reports it. Even if I had left the black bars in, it would only have been 720 X 404, not even all the way to 480p.

Repeating myself, but the old method was more accurate.

38

@JuiceWSA said:
Nope. Even if you crop out the black bars the item will still be stored at 720x576. Cropping determines the final vertical display resolution the player will dutifully display, for widescreen letterbox and 4:3 providing you use a correct ‘Width’ setting, but no matter what you do the item will still be stored at 720x576. 4:3 material is also stored at 720x576. A proper Anamorphic ‘Width’ setting for 4:3 will be - I think - 768 resulting in the final displayed resolution of 768x576. If I lived in PAL-Land I would know what a 4:3 image should be, but I do not. Anamorphic was invented when 16:9 displays came around, but DVDs can’t hold the full resolution - so an Industry Wide Work Around was invented. That is now the Industry Standard On Planet Earth. That’s the long and the short of it.

I know the frame is always stored at 720x576, and for 4:3 or 16:9 the pixel aspect ratio is changed accordingly so the 4:3 image can fill a 4:3 screen, and the 16:9 image can fill the 16:9 screen. This formats were developed with analog TV in mind therefore “non square pixel” were the norm to adapt the stored resolution to the display width (which was “analog”, that is there was not the concept of horizontal pixel size, while there was the concept of vertical “line size” since the number of rows was always the same.

So, the only doubt I have is, let’s assume there’s a movie with a “wider than 16:9” aspect ratio, say 1.85:1, how will it be stored on the disk? Is it just a 720x576 frame with horizontal black bars displayed at 16:9 in full screen, using the whole vertical resolution but actually wasting some resolution (both on screen and on disk) for the black bars, or is it a 720x576 frame with 1.85:1 anamorphic settings, that’s stretched to 16:9 and added black bars to maintain the displayed aspect ratio of 1.85:1 on a 16:9 screen? That would mean that the resolution stored on disk is actually higher (576 lines) than the one shown on display (576 minus the black bars).

39

@leelynds said:
My original post was regarding a video encoded at 720 X 404. It’s a pretty common resolution meant for a 16:9 display, at what I would consider SD or 480p.

It’s a simple, straight forward reduction in size, from a 1280 X 720 video encoded at ridiculously low rates for one user I share with who has the world’s slowest internet connection. I like to avoid on-the-fly transcoding whenever possible, even though the server is more than capable of doing so.

I get your point, my suggestion would be to encode it in 720x480 anamorphic, you’ll have much better vertical resolution, a “true” 480p format, and not a big hit on bandwidth. We are less sensitive to horizontal resolution so once stretched to fill the screen 720x480 will look pretty good.

Since the original video does not have the anamorphic flag set, I don’t see the need to encode it as a 16:9 DVD rip at 720 X 480 and set the anamorphic flag so it displays correctly.

You mean the original video is 720x480 letterboxed? Then your solution is obviously the best and no need to use anamorphic.

As I stated originally, this particular resolution (720 X 404) used to be reported as SD. It made sense to me - the vertical resolution wasn’t quite 480p, definitely not 576p, but the horizontal resolution of 720 fit into both NTSC and PAL standards for the old 4:3 standard definition displays.

I was surprised that all of a sudden all of the SD versions had been “up-graded” (as @JuiceWSA said) to 576p. That’s a big jump from SD, leap-frogging over 480p, up to 576p.

I suspect Plex is thinking that 720x404 is a cropped 720x576 frame, devoid of black bars. That of course doesn’t qualify this as 576p on any planet of the solar system: 16:9 576p is a frame of 720x576 with 16:9 anamorphic output and no black bars at all. The issue that might arise for wider than 16:9 aspects (the one I’m discussing above) doesn’t apply here at all, so there’s no ambiguity. Also, 576p is usually 25fps or 50fps, and your is probably 30fps, right? To close the discussion, it could be a 720x576 frame with letterbox to 16:9, but then the width/height ratio of the cropped one should NOT be 16:9 exactly, because even in 4:3 the pixels are not “square”

40

@JuiceWSA said:
Nope. Even if you crop out the black bars the item will still be stored at 720x576.

I read somewhere that, for example, DVDs can only do anamorphic to 16:9, therefore they need to letterbox “wider” formats to 16:9. But I read somewhere else that this is not true and every aspect ratio can be used for anamorphic widescreen on DVD. That’s nice, I didn’t know that.