2023-07-20, 13:45
Hi,
I wrote a Kodi addon to a local TV broadcaster. They have widevine/playready protected audio and video streams and they use MPEG-DASH to stream their livestreams. However there is often a subtitle track too (that's not DRM protected). From their web player that works fine. Kodi on the other hand recognizes the subtitle, I can even turn it on, but it won't render.
I did some digging so I let the official player start the playback and downloaded the init segment for the subtitle and the first chunk. I appended them together so you can take a look yourself. This is a single chunk of the sub: http://users.atw.hu/mrdini/secret/subtit...e_sstp.mp4
The manifest suggests its SSTP:
Which mediainfo also confirms on the downloaded file.
I have no idea how to extract the subs from this file even other than extracting the raw XML by seeking to the place where the raw xml starts in the file. It seems that its actually ttml format, but they use base64 encoded images. If I convert it manually, I get back the right subtitle chunk.
But I am unsure. I could probably create a method that converts the subtitles, but since its on the fly I am not sure what would be the best way to grab these subtitles, convert them into a format that kodi handles and feed it to the player. Any ideas?
I wrote a Kodi addon to a local TV broadcaster. They have widevine/playready protected audio and video streams and they use MPEG-DASH to stream their livestreams. However there is often a subtitle track too (that's not DRM protected). From their web player that works fine. Kodi on the other hand recognizes the subtitle, I can even turn it on, but it won't render.
I did some digging so I let the official player start the playback and downloaded the init segment for the subtitle and the first chunk. I appended them together so you can take a look yourself. This is a single chunk of the sub: http://users.atw.hu/mrdini/secret/subtit...e_sstp.mp4
The manifest suggests its SSTP:
Code:
<AdaptationSet id="3" group="3" contentType="text" lang="en" mimeType="application/mp4" codecs="stpp" startWithSAP="1">Which mediainfo also confirms on the downloaded file.
Code:
General
Format : iso6
Codec ID : iso6 (iso6/dash)
File size : 24.4 KiB
Duration : 2 s 0 ms
Overall bit rate : 99.9 kb/s
Text
ID : 1
Format : stpp
Codec ID : stpp
Duration : 2 s 0 ms
Bit rate : 96.4 kb/s
Frame rate : 0.500 FPS
Stream size : 23.5 KiB (97%)
Language : English
Forced : No
I have no idea how to extract the subs from this file even other than extracting the raw XML by seeking to the place where the raw xml starts in the file. It seems that its actually ttml format, but they use base64 encoded images. If I convert it manually, I get back the right subtitle chunk.
But I am unsure. I could probably create a method that converts the subtitles, but since its on the fly I am not sure what would be the best way to grab these subtitles, convert them into a format that kodi handles and feed it to the player. Any ideas?
