@leelynds said:
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.
I completely agree. There’s no way one could call 720x306 a “576p” format. If it was a cropped 720 x 576 screen (e.g. a PAL 16:9 movie letterboxed for 4:3 screens) it should have a different resolution and an anamorphic setting to correct the pixel aspect ratio. Let’s be clear, what Plex is misunderstanding here is that no 576p with square pixel exists. It never was, it never will. So if you have a 720 x something that has a storage aspect ratio of 16:9 and a display aspect ratio of 16:9 that’s not 576p.
@leelynds said:
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.
I was made to derail threads. It’s in my genetic makeup.
The reason your SD rip isn’t correctly being identified as SD is all mixed up in this magic pancake batter that Plex has sprayed all over the kitchen. The entire shebang is currently completely broken. Once they fix some things everything will start coming back into whack from it’s current out of whack condition.
We hope.
SD, as you know already, is how Plex identified anything that didn’t quite make it to 480 or 576. Stuff that didn’t quite age long enough to become the real McCoy. They’re squirting something out of can and putting it on a cracker, but it ain’t cheese.
@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.
‘Letterboxed’ is short - bars atop and below.
‘Pillarboxed’ is skinny - bars left and right.
‘Knotholed’ - bars all around - is a screwed up encode. Back to the drawing board with ye!
LOL
There are different ‘flavors’ of widescreen material that require a little bit of fiddling in the Width setting, but most of the time a good crop-job will sort it all out automatically.
’
Television signals are transmitted in digitally encoded form, and the lines are scaled to fit SMPTE SDI bandwidth requirements, as opposed to unrestricted uses such as when lines are rendered or overlaid to a modern computer monitor and modern SMPTE implementations of HDTV. The table below summarizes pixel aspect ratios for the scaling of various kinds of SDTV video lines. Note that the actual image (be it 4:3 or 16:9) is always contained in the center 704 horizontal pixels of the digital frame, regardless of how many horizontal pixels (704 or 720) are used. In case of digital video line having 720 horizontal pixels, only the center 704 pixels contain actual 4:3 or 16:9 image, and the 8 pixel wide stripes from either side are called nominal analogue blanking for horizontal blanking and should be discarded before displaying the image. Nominal analogue blanking should not be confused with overscan, as overscan areas are part of the actual 4:3 or 16:9 image.
Video format Display aspect ratio (DAR) Resolution Pixel aspect ratio (PAR) After horizontal scaling
576i 4:3 704×576
(horizontal blanking cropped) 12:11 768×576
720×576 (full frame) 786×576
The pixel aspect ratio is always the same for corresponding 720 and 704 pixel resolutions because the center part of a 720 pixels wide image is equal to the corresponding 704 pixels wide image.
@JuiceWSA said:
There are different ‘flavors’ of widescreen material that require a little bit of fiddling in the Width setting, but most of the time a good crop-job will sort it all out automatically.
What I mean is, are there any DVD that store in a 720x576 frame the full image of a 1.85 or 2.35 movie, squeezed without letterboxing, or are 1.85 and 2.85 movies (or other aspects) just letterboxed to a 16:9 screen size before being squeezed horizontally to the usual 720x576 frame?
Edit: To answer my own question: http://www.mpeg.org/MPEG/DVD/Book_B/Video.html “aspect ratio is the display aspect ratio. Only 16:9 and 4:3 are permitted” that is: 1.85:1 or 2.35:1 original material will be letterboxed with black bars to be displayed as full screen on a 16:9 screen
@Gdr56 said:
The pixel aspect ratio is always the same for corresponding 720 and 704 pixel resolutions because the center part of a 720 pixels wide image is equal to the corresponding 704 pixels wide image.
And you can see the 16 black pixels when you look at a DVD frame in the encoding software. But I was always confused by the fact that, for example, having worked with Lightwave 3D a lot the default resolution for “D1:- PAL Widescreen” was 720x576 with a pixel aspect ratio of 1.4222…
@JuiceWSA said:
There are different ‘flavors’ of widescreen material that require a little bit of fiddling in the Width setting, but most of the time a good crop-job will sort it all out automatically.
What I mean is, are there any DVD that store in a 720x576 frame the full image of a 1.85 or 2.35 movie, squeezed without letterboxing, or are 1.85 and 2.85 movies (or other aspects) just letterboxed to a 16:9 screen size before being squeezed horizontally to the usual 720x576 frame?
Edit: To answer my own question: http://www.mpeg.org/MPEG/DVD/Book_B/Video.html “aspect ratio is the display aspect ratio. Only 16:9 and 4:3 are permitted” that is: 1.85:1 or 2.35:1 original material will be letterboxed with black bars to be displayed as full screen on a 16:9 screen
If you don’t encode the black bars your TV will add those in at playback.
DVD storage is DVD storage. Storage size DOES NOT equal Final Displayed size. Anamorphic settings tell the player what to do with the stored size when it’s blown up to it’s full size for display on your TV. If the full size is letterboxed - say, 854x420, like some form of letterboxing, that’s the size of the picture sent to your TV and the TV adds black bars where necessary.
Storage remains storage. Anamorphic settings tell the player/TV how to display the stored resolution to it’s full glory.
Using proper Anamorphic Settings…
Here is a 640x480 final displayed product as it’s shown on the TV. It will be Pillarboxed. It is 4:3. All back bars have been cropped out and will be added back in on the TV at playback time:
Here is the Expanded Super-Duper Widescreen Letterboxed version of “Bus Stop (1956)” as it’s displayed on the TV - all black bars above and below have been cropped out. The TV will add those black bars back in at playback time:
Here is the same as it looks in storage at 720x480:
Storage has nothing to do with final products after proper anamorphic settings have worked their magic.
All Plex has to do is look at the Storage res and report that correctly. Proper encoding handles it from there.
Note: That above is the super-duper original widescreen “Bus Stop (1956)” in 480p, properly encoded from DVD. I have had an opportunity to upgrade my Bus Stop (1956) to a 1080p version, but every time I see one, some mouth-breathing Executive Idiot has decided that punching a hole in the original 2.35:1 (or whatever) and making it 1.85:1 16:9 (or whatever) is a ‘good idea’ and every time I have said: No Thanks.
There is nothing wrong with a good 480p encode at it’s original aspect ratio.
@“MovieFan.Plex” said:
… Plex chose to keep 640x480 for 480p and 768x576 for 576p, so this video fits into the 576p category… The same argument can be made for extremely high aspect ratio videos such as 1920x720. Would this be 720p to fit the vertical or 1080p to fit the horizontal. Plex uses 1920x1080 and 1280x720p boxes and since it won’t fit in the 1280x720, this would be 1080p.
and
Can you give me a table of the resolution ranges that should be used for the various labels?
If I understand the above statements, Plex chose basically to use a standard 16X9 aspect ratio, and anything that fits into that “box” both vertically and horizontally is given that resolution. If either is greater, the reported resolution is bumped up until it fits in a “box”
Working on that assumption, I came up with this table, that might work. I think it takes into account videos encoded with or without the anamorphic flag for DVD rips. I’ve given examples of several common resolutions/ aspect ratios, from super widescreen to 4X3. In each case, if either the horizontal or vertical size doesn’t fit into the 16X9 box, it should be bumped up to the next resolution, and I think reported cirrectly and acceptable to most.
4K or 2160p (3840 X 2160)
3840 X 1392 (2.76 aspect ratio)
3840 X 1600 (2.4 aspect ratio)
3840 X 1634 (2.35 aspect ratio)
3840 X 2076 (1.85 aspect ratio)
3598 X 2160 (1.66 aspect ratio)
2880 X 2160 (1.33 aspect ratio)
1080p (1920 X 1080)
1920 X 696 (2.76 aspect ratio)
1920 X 800 (2.4 aspect ratio)
1920 X 816 (2.35 aspect ratio)
1920 X 1036 (1.85 aspect ratio)
1800 X 1080 (1.66 aspect ratio)
1440 X 1080 (1.33 aspect ratio)
720p (1280 X 720)
1280 X 464 (2.76 aspect ratio)
1280 X 532 (2.4 aspect ratio)
1280 X 544 (2.35 aspect ratio)
1280 X 692 (1.85 aspect ratio)
1200 X 720 (1.66 aspect ratio)
960 X 720 (1.33 aspect ratio)
576p (1024 X 576)
1024 X 372 (2.76 aspect ratio)
1024 X 428 (2.4 aspect ratio)
1024 X 436 (2.35 aspect ratio)
1024 X 552 (1.85 aspect ratio)
960 X 576 (1.66 aspect ratio)
768 X 576 (1.33 aspect ratio)
720 X 576 (PAL DVD with anamorphic flag of 4:3 or 16:9)
480p (854 X 480)
854 X 310 (2.76 aspect ratio)
854 X 356 (2.4 aspect ratio)
854 X 364 (2.35 aspect ratio)
854 X 362 (1.85 aspect ratio)
796 X 480 (1.66 aspect ratio)
640 X 480 (1.33 aspect ratio)
720 X 480 (NTSC DVD with anamorphic flag of 4:3 or 16:9)
SD (720 X 404)
720 X 260 (2.76 aspect ratio)
720 X 300 (2.4 aspect ratio)
720 X 306 (2.35 aspect ratio)
720 X 390 (1.85 aspect ratio)
672 X 404 (1.66 aspect ratio)
538 X 404 (1.33 aspect ratio)
360p (640 X 360)
640 X 232 (2.76 aspect ratio)
640 X 266 (2.4 aspect ratio)
640 X 272 (2.35 aspect ratio)
640 X 346 (1.85 aspect ratio)
598 X 360 (1.66 aspect ratio)
480 X 360 (1.33 aspect ratio)
I’m sure I’ve missed some oddball resolutions, and I’m sure this won’t please everyone. Maybe a new starting point to consider…
You forgot 704x480 - likely to be an NTSC Broadcast TV 480p res.
If my “guzintas” and “not times nots” were all ciphered properly, 704 X 480 fits nicely in the definition for 480p, because of the vertical resolution.
I’ve been wondering why Plex was telling me my recorded TV shows are 576p - was hoping this thread would provide the answer.
Now, after reading the entire thread, I’ve come to the conclusion that there isn’t a good reason that Plex is identifying 704x480 as 576p. In the scheme of things, it (probably) doesn’t matter - except it’s wrong.
You forgot 704x480 - likely to be an NTSC Broadcast TV 480p res.
If my “guzintas” and “not times nots” were all ciphered properly, 704 X 480 fits nicely in the definition for 480p, because of the vertical resolution.
But with the reasoning of some Plex employee throughout the thread, how do you know this is not a 704x576 DVD 16:9 anamorphic with 2.35:1 letterbox, that is a frame with a 720x436 image and 70 pixel black bars on top and bottom, cropped to 720x436 and then for no reason anamorphically stretched to a 480 pixel vertical resolution? Silly you say? I agree.
@JuiceWSA said:
Storage remains storage. Anamorphic settings tell the player/TV how to display the stored resolution to it’s full glory.
Exactly, but bear in mind that, to my knowledge, a DVD frame of 720x576 can ONLY be anamorphic to 4:3 or anamorphic to 16:9. There’s no “full frame 720x576” with anamorphic 2.35:1 for example. On a DVD 1.85:1 and 2.35:1 are always obtained letterboxing a 16:9 anamorphic 720x576. That’s the reason why a cropped 2.35:1 DVD rip won’t have a vertical resolution of 576 pixels
On the other hand if your source is a 1080p bluray, where there’s no anamorphic at all and you only have wider formats through letterboxing, it makes sense to use the anamorphic factor you prefer.
Note: That above is the super-duper original widescreen “Bus Stop (1956)” in 480p, properly encoded from DVD.
And is the storage frame image on the DVD in this case 480 pixel tall? In my experience it is not, because “wider than 16:9” movies has letterbox black bars in the storage.
Also, I’ve found it useful to reduce size to encode some media from 1080p to a “custom” resolution of 540p, with or without anamorphic: it’s exactly half the vertical resolution of a 1080p TV and scaling looks pretty good.
@zpaolo11x said:
But with the reasoning of some Plex employee throughout the thread, how do you know this is not a 704x576 DVD 16:9 anamorphic with 2.35:1 letterbox, that is a frame with a 720x436 image and 70 pixel black bars on top and bottom, cropped to 720x436 and then for no reason anamorphically stretched to a 480 pixel vertical resolution? Silly you say? I agree.
Clearly, you have not yet wrapped your head around the difference between ‘Storage’ and ‘Final Displayed’ resolutions for DVD material. I fear this is also the case over there at Plex HQ.
@zpaolo11x said:
Exactly, but bear in mind that, to my knowledge, a DVD frame of 720x576 can ONLY be anamorphic to 4:3 or anamorphic to 16:9. There’s no “full frame 720x576” with anamorphic 2.35:1 for example. On a DVD 1.85:1 and 2.35:1 are always obtained letterboxing a 16:9 anamorphic 720x576. That’s the reason why a cropped 2.35:1 DVD rip won’t have a vertical resolution of 576 pixels
The ‘Storage’ will be 720x576. The Storage is what Plex looks at to determine it’s resolution. That’s the way it’s always been and is the correct way. A DVD disc can NOT hold a large format. The DVD disc can only hold 720x480 (NTSC) or 720x576 (PAL)
On the other hand if your source is a 1080p bluray, where there’s no anamorphic at all and you only have wider formats through letterboxing, it makes sense to use the anamorphic factor you prefer.
No Anamorphic setting is required for HD material. The ‘Storage’ is the same as the end product. BluRay discs can hold large formats. DVDs can not.
Note: That above is the super-duper original widescreen “Bus Stop (1956)” in 480p, properly encoded from DVD.
And is the storage frame image on the DVD in this case 480 pixel tall? In my experience it is not, because “wider than 16:9” movies has letterbox black bars in the storage.
The Storage is 720x480 as you can see because it’s all out of whack with a destroyed aspect ratio while in ‘Storage’. Black Bars have been cropped out. The final 854x364 (per @leelynds most excellent post and scholarly ‘sifering’ above) is hammered into 720x480 storage, annihilating it’s aspect ratio - until playback when it’s anamorphic settings make the ‘ugly caterpillar’ hatch from it’s cocoon and become a beautiful butterfly at 854x364. Plex need only look at the storage (720x480) to identify it correctly.
Also, I’ve found it useful to reduce size to encode some media from 1080p to a “custom” resolution of 540p, with or without anamorphic: it’s exactly half the vertical resolution of a 1080p TV and scaling looks pretty good.
You can use Wombat Squad encoding techniques if you want to. Over here in Juicetown, HomeSlice plays by the rules laid down by ‘The Industry Standard’.
The correct way to encode something like that would be to use a custom anamorphic ‘Width’ setting of 1024 and store it at 720x576. The Industry Standard for DVD in PAL territory. https://forums.plex.tv/discussion/comment/1335697/#Comment_1335697
^Read all about it^.
I actually do that all the time when I record something from The Wombat Squad’s PBS tower 3 miles from here and ‘The Squad’ has upscaled SD material to 1920x1080. It actually looks better back down where it was originally. I store it at 720x480 and maintain it’s aspect ratio by correct, Non-Wombat encoding techniques.
If I wanted to ‘save some space’ I would never knock down a proper HD item to SD. I would simply reduce the bit rate of the original material to some degree. My eyeballs would tell me where to stop.
@zpaolo11x said:
But with the reasoning of some Plex employee throughout the thread, how do you know this is not a 704x576 DVD 16:9 anamorphic with 2.35:1 letterbox, that is a frame with a 720x436 image and 70 pixel black bars on top and bottom, cropped to 720x436 and then for no reason anamorphically stretched to a 480 pixel vertical resolution? Silly you say? I agree.
The PAL vs NTSC ripped DVD thing is obviously the problem.
From your example, I would imagine with the method previously used by Plex, your PAL videos were identified as 480p, which you could decide was not right. Worked perfectly for me, being an NTSC guy, and would be marked as either 480p or SD. With the current method, I’m pretty sure you would get the 576p identification, and therefore, think it’s labelled properly. I could argue that since you have cropped some pixels off it, it’s no longer 576p and should be identified as a something less than - sort of like in my examples above, that a 720X404 video is neither a 480p or 576p video, but an SD video. That might be considered sort of one sided on my part.
I suppose, to complicate the decision, the frame rate could be considered in the PAL vs NTSC thing. I believe PAL videos are always 25FPS, and NTSC are either 23.976 or 29.97 FPS.
Note: That above is the super-duper original widescreen “Bus Stop (1956)” in 480p, properly encoded from DVD.
And is the storage frame image on the DVD in this case 480 pixel tall? In my experience it is not, because “wider than 16:9” movies has letterbox black bars in the storage.
The Storage is 720x480 as you can see because it’s all out of whack with a destroyed aspect ratio. Black Bars have been cropped out.
So the “storage” frame was 480 pixel tall with black bars. The “image frame” was 364 pixel tall, plus black bars. As I mentioned many times before, there’s no anamorphic 2.35:1 DVD format, therefore all widescreen formats (wider than 16:9) have a frame with black bars.
The final 854x364 (per @leelynds most excellent post and scholarly ‘sifering’ above) is hammered into 720x480 storage annihilating it’s aspect ratio - until playback when it’s anamorphic settings make the ‘ugly caterpillar’ hatch from it’s cocoon and become a beautiful butterfly at 854x364. Plex need only look at the storage (720x480) to identify it correctly.
This doesn’t make sense to me. If the storage format is 720x480 with black bars and the picture frame is 720x364 you either encode it as 720x364 (cropped black bars) with display AR of 2.35:1 or you leave the black bars and you encode to 720x480 with 16:9 anamorphic ratio (wasting some file data to encode useless black bars, but retaining a “full” 480p frame).
There’s no point in enlarging it to 854x364 unless you are really a fan of square pixel or you have a native display 854 pixel wide, which I doubt. And there’s no point in taking the image frame (720x364) and encode it as 720x480, actually stretching it vertically to fit a storage frame of 720x480. It’s an useless upscaling.
Also, I’ve found it useful to reduce size to encode some media from 1080p to a “custom” resolution of 540p, with or without anamorphic: it’s exactly half the vertical resolution of a 1080p TV and scaling looks pretty good.
You can use Wombat Squad encoding techniques if you want to. Over here in Juicetown, HomeSlice plays by the rules laid down by ‘The Industry Standard’.
The correct way to encode something like that would be to use a custom anamorphic ‘Width’ setting 1024 and store it at 720x576. The Industry Standard for DVD.
Sure, we all like and love industry standards, and we all like and love to not mess with resolution. Too bad that I’m not encoding DVDs but digital files to view in Plex on a 1080p screen with square pixels, and in my example the source is 1080p. What’s the point to scale it to 576 when there are other resolutions that much better fit the original material, therefore less scaling artifacts?
@leelynds said:
I suppose, to complicate the decision, the frame rate could be considered in the PAL vs NTSC thing. I believe PAL videos are always 25FPS, and NTSC are either 23.976 or 29.97 FPS.
What scares me is that a Plex employee asks what “resolutions” should be considered 576p or 480p. It’s not “resolution” in itself. If you want to use that definition you just need to analyze the storage resolution, the pixel aspect ratio and the frame rate. With that approach you can reconstruct the history of most rips, and only hardcoded black bars would fool you, but hardcoded black bars are ususally just in 480 or 576 pixel tall storage frames. It’s not difficult, it only requires knowledge of formats
@JuiceWSA said:
The Storage is 720x480 as you can see because it’s all out of whack with a destroyed aspect ratio while in ‘Storage’. Black Bars have been cropped out. The final 854x364 (per @leelynds most excellent post and scholarly ‘sifering’ above) is hammered into 720x480 storage, annihilating it’s aspect ratio - until playback when it’s anamorphic settings make the ‘ugly caterpillar’ hatch from it’s cocoon and become a beautiful butterfly at 854x364. Plex need only look at the storage (720x480) to identify it correctly.
Wait, are you telling me you take a 720x480 storage frame, with 720(probably 704)x364 image frame+black bars, crop the black bars and encode it to a storage frame of 720x480 anamorphic?!? Why not encode it to 720x364 instead, I mean, what’s the point to stretch the “useful” 364 lines to the full 480 line? It’s just artifacts.
