I was wondering how Plex agents are determining the resolution that is shown for a movie.
I would have assumed that http://en.wikipedia.org/wiki/List_of_common_resolutions#Digital_TV_standards
would be a reference of sorts. So I expected the scan lines to be the determining factor.
Looking at width, height and the resolution Plex has derived for a couple of movies shows a slightly different picture:
width height resolution
1920 1088 1080p
1912 792 1080p
1280 674 720p
1280 534 720p
720 576 576p
720 544 576p
720 424 480p
624 400 480p
608 352 SD
Generally, the resolution Plex is showing is often one category better, than what I would have assigned.
I don't have any real preference for the algorithm used to derive the resolution, but i'd like to understand it.
Could anyone shed some light on this?
i am guessing he blue ones are the ones you think are wrong.
i think you need to think of 720p as a marketing term representing quality rather than a strict rule that it must be that many lines high
1280x720 is 720p
1280x674 is also 720p because the density of the pixels is still the same even though there are black bars at the top and bottom
imagine if you took a 1280x720 image on a 720p tv but took two pieces of long black paper and covered up 23 pixels at the top and 23pixels at the bottom. the image quality is still the same even though the aspect ratio is different
this is how i have always understood it anyway.
some of the ones are i think "close enough". like the 1912x792 1080p is probably just because of a bit a cropping some ripping apps are set to do. but the original was probably 1920 wide.
admittedly i cannot explain the reasoning for the ones that are 720 wide
( i understand you may be asking how exactly it is programed to do so and not my reasoning above, but i think that is done via analysis on the server not via an agent/scanner)
