In some cases, direct play is not performed due to subtitles, and transcoding is required, despite playback as original.
But many people who use Plex often only care about the Plex server but don’t think about the device that plays the Plex. Although Plex is heavily influenced by server settings, plex clients and devices are much more important.
Plex Not Finding Subtitles
First, the subtitle formats supported by Plex are as follows.
- Plex is famous for the convenience of accessing multiple media database. It is also called Plex Media Server; you can see many PMS on computers or some NAS devices. While it is being a client-server media player suite, most people use it simply as an organizing tool for their media content libraries.
- BDSup2Sub is a converter from Blu-Ray PGS SUP to DVD SUB/IDX (VobSub) or SUP(DVD SUP). You can also add a delay and/or change the time stamps to e.g. Perform a PAL speedup.
- Therefore, Leawo Video Converter was born with the purpose of fixing Plex subtitles out of sync issues. It implants all the necessary media codecs to support Plex movies even in 4K MP4, MKV. The external subtitle files are available in the formats of SRT, ASS, SSA. On top of that, the extraneous audio soundtrack is addable to Plex movies as well.
Plex's trailer feature also supports displaying trailers from a URL - the metadata agent just needs to add the relevant URL at which Plex can reach the trailer. If we added support for this, it'd mean that user who don't have the trailer as a file can also benefit from having the trailer available.
Basic support: SRT, SMI, ASS, SSA, WebVTT
Device specific support: PGS, VOBSUB
However, if the playback device does not support the caption even if Plex supports, Plex will transcode it.
Two major devices are devices for most of Plex users. (1) TV, (2) smartphone.
For TVs, there are many different types of subtitles that can be played. Google search using keyword like “the supported subtitle format for LG Smart TV”Antonio lopez artwork. shows the default subtitle format supported by LG Smart TVs. (See the manufacturer’s website for the most accurate information)
For LG Smart TVs, the supported subtitles are SMI, SRT, SUB, ASS, SSA, TXT, and PSB formats. Most of Koraen are using SMI Subtitles format and LG TVs support that.
Therefore, SMI subtitles are “basically supported” on the Plex run by LG TV. If your plex application on LG TV transcode your videos, it is likely to be a different problem, not a subtitle. (It is likely to be an video format or audio format not supported by TV)
Plex Srt Subtitles
For Samsung H-series TVs, the supported subtitles are TTXT, SMI, SRT, SUB, TXT, SSA, ASS, PSB and XML. Therefore, SMI, SRT, ASS, and SSA subtitles are working without transcoding in the Plex for Samsung TV.
(2) Smartphone (Android)
I couldn’t test the Apple devices because I don’t have any. So, here’s a description of the Android device.
The Plex app on Android uses the EXO Player. The format of subtitles that can be played in the EXO Player is as follows:
WebVTT, TTML, SMPTE-TT, SRT, SSA, ASS
In other words, only WebVTT, SRT, SAA, and ASS formats can be played directly on the Plex Android app. Therefore, your device always transcode SMI subtitle files.
Note: As I mentioned above, “SMI files are unconditionally transcoded in Plex application” is not true. It depends on the device you use.
In conclusion, it will be inconvenient for the people who use Plex for both TV and smartphone to use SMI subtitle format. In this cases, those people need to convert SMI to SRT. However, if you are a TV lover, you don’t have to convert SMI to SRT. (If your TV supports that.)
De nuptiis Philologiae et Mercurii et de septem artibus liberalibus. Author: Martianus Minneus Felix Capella (a native of Madaura, floruit 5th century AD in Carthage) Editor: Ulrich Friedrich Kopp (Cassel [now Kassel], 18 March 1762 – 27 March 1834,..More
De nuptiis Philologiae et Mercurii et de septem artibus liberalibus. Author: Martianus Minneus Felix Capella (a native of Madaura, floruit 5th century AD in Carthage) Editor: Ulrich Friedrich Kopp (Cassel [now Kassel], 18 March 1762 – 27 March 1834, Marburg) Publication Data: Frankfurt-am-Main, 1836 Note: Kopp died while visiting Carl Friedrich Hermann (Frankfurt-am-Main, 4 August 1805 – 31 December 1855, Göttingen) in Marburg. It was Hermann who finished this volume and who saw it through the press. For best viewing, download PDF.LessRead the publication