I took the advice and try out the other stream profile, and below are the summary of my testing, as you can see, the "only 1 subtitle" problem still exists. Is this the limitation of Tvheadend transcoding function, or are there any workarounds to fix this?
1. Kodi TVheadend HTSP PVR Client only accept these profile: empty, htsp, "Transcode/av-lib"; other than these it will just report "The streaming profile is not available".
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2. I think empty and htsp profile is the same, as default profile the pvr client used is htsp.
3. "Transcode/av-lib" means the custom profile(what ever name you gave it) created from "Transcode/av-lib"; I also found out that this is the only profile that I can try out "VAAPI transcoding with GPU" codec profile.
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4. Although htsp profile works, but it has these problems when viewing live tv /recordings on my tvbox kodi:
4.1. I cannot watch live tv/recordings in Kodi's mediacodec hw accelerated mode, unless I turns them off.
4.2. This is very annoying as I have to constantly turning on/off "Kodi's mediacodec hw accelerated mode" to watch live tv/recording and anythings else.
4.3. Besides annoying, without the hw accelerated mode, the cpu usage will be very high, had to turn off deinterlacing, to prevent the channel from stuttering.
5. Although "Transcode/av-lib" also works, but it has the problem that i am trying to solve now:
5.1. which is when viewing live tv /recordings on my tvbox kodi(via Kodi TVheadend HTSP PVR Client with the "Transcode/av-lib" streaming profile), the channel has only 1 subtitle, but the channel originally has more than 1 subtitles.
5.2. No matter what codec profile(including "VAAPI transcoding with GPU") I used in this streaming profile, the "only 1 subtitle" problem still exists.
5.3. I tried setting up Subtitle Stream Filters, the "only 1 subtitle" problem still exists.
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