Feature Request: Support DTS/TrueHD local Transcoding

[Rofocale11]

Hallo, My TV is patched with dts_restore_plus, but on plxnative the patch doesnt work even with force directplay enabled, on plex official app the patch works, so i was hoping it can be fix or add transcoding audio on the client as a feature, thanks.

[GLinnik21]

Hey, thanks for the report. With Force Direct Play on, DTS should be passed to the TV even if the TV doesn't declare it, so this one shouldn't be getting blocked by us. I'd like to see what actually happens on your set.

Could you send:

• your TV model and webOS version
• the audio track of the file you tried: in Plex, Get Info > View XML, and the audio stream's codec, profile and channels (plus whether the file has other audio tracks)
• what the player shows when it fails (a photo of the error screen with the small line at the bottom is perfect), or whether it plays with no sound
• the app log from right after a failed attempt: /tmp/plxnative-events.log on the TV (you have ssh since you're rooted). Skim it before posting and blank out anything private like server addresses or tokens
• the output of grep avdec_dca /etc/gst/gstcool.conf on the TV, if you can

Also, as far as I can tell dts_restore only gives stereo PCM from DTS, so don't expect multichannel or passthrough out of it.

[grole]

Here’s the requested information:

LG C2 (OLED65C26LD)
33.31.68 webOS 25
PlxNative 0.9.0

grep avdec_dca /etc/gst/gstcool.conf
avdec_dca=0

Plex XML info: audioChannels="6" audioCodec="dca" audioProfile="dts"
The file also has a secondary ac3 track.

plxnative-events.log

Error with direct play forced:

Error with direct play auto:

[froleo]

I'm experiencing the same issue.
DTS Direct Play works in the official Plex app with force direct play after patch, but PlxNative fails with similar errors listed above.

O24_DVB * BOARD_DV_1ST * playback_policy

TV: LG G5 77 (OLED77G54LW.DEUQLJP)
webOS: 26 (11.2.0-3706)
Firmware: 43.21.77
Root: Yes, Homebrew Channel 0.8.0
PlxNative: 0.9.0
DTS Restore Plus: Enabled (experimental mode / unverified tv)
Soundbar: Samsung HW-Q950T via eARC

Enabling "Show DTS tracks in apps" in DTS restore didn't help either.

[GLinnik21]

Thanks both, this helps a lot. It looks like two different failures, so I'll take them separately.

@grole: with Force Direct Play on, the app sends the DTS track to the TV's player as DTS. The player refuses the Load before any picture: type=18 num=601 "Resource Allocation Error", right after it reports audio/x-dts. That error is the pipeline refusing to allocate what the Load asked for. We've seen it before for an over-sized video declaration, but the video declaration in your log is the one we've measured working, so the DTS audio is my next suspect. I haven't confirmed that. Auto shows the same failure screen, but I don't have its log yet.

@froleo: your screen ends in playback_policy, which is Force Direct Play refusing the track before anything is sent to the TV. That usually means the TV's codec table has no DTS entry, so it's a different problem from grole's. I need your log to confirm it.

Could you send:

• @grole: the events log from an Auto-mode attempt, and (you have ssh) the full /etc/gst/gstcool.conf plus what dts_restore_plus installed on your set (its hook under /var/lib/webosbrew/init.d/ and any files it changed). Blank out anything private.
• @froleo: the events log from a failed attempt, and your gstcool.conf.
• Both: does the file play if you pick the AC3 track?

I'm tracking this in #915.

[froleo]

@GLinnik21

After further investigation, I also get a TV pipeline error with a different file containing only one DTS audio track.

The original issue occurred when switching from Dolby Digital 5.1 to TrueHD during playback. Dolby Digital 5.1 works. The log shows that TrueHD selections are rejected by playback_policy, while the latest DTS attempt reaches the native pipeline and fails with 601: Resource Allocation Error.

The DTS attempt also logs DTS core extraction on (DTS-HD extensions discarded).

The attached events log includes earlier playback attempts; the latest DTS test starts around line 9956. A summary and my /etc/gst/gstcool.conf contents are below.

plxnative-events.txt

Attempt	Audio	Result
Film with five audio tracks, played three times	AC3 selected	Native load succeeds
TrueHD selection, twice	TrueHD	Rejected by playback_policy
Two trailer/preview attempts	AAC	Native loads succeed; previews later stopped
Latest film with one audio track	DTS	TV pipeline rejects it with 601: Resource Allocation Error

cat /etc/gst/gstcool.conf

[buffering]
max-size-buffers=0
max-size-bytes=25165824
max-size-time=20000000000
low-percent=10
high-percent=99
ring-buffer-max-size=0
use-rate-estimate=1

[rank]
mpegpsdemux=310
decproxy=300
omx_lxvideosink=256
omx_lxvideodec=290
alsasink=0
mediainfo=64
aac_audiodec=290
ac3_audiodec=290
ac4_audiodec=290
adpcm_audiodec=290
amr_audiodec=290
dts_audiodec=290
flac_audiodec=290
mpegh_audiodec=290
pcm_audiodec=290
vorbis_audiodec=290
wma_audiodec=290
avenc_ac3=0
avenc_eac3=0

[sw_decoder]
avdec_truehd=310
avdec_mlp=310
avdec_mp3=0
avdec_aac=0
avdec_ac3=0
avdec_alac=0
avdec_amrnb=0
avdec_amrwb=0
avdec_eac3=0
wavpackdec=0
avdec_wmapro=0
avdec_wmav1=0
avdec_wmav2=0
avdec_wmavoice=0
alawdec=0
mulawdec=0
avdec_flac=0
adpcmdec=0
dvdlpcmdec=0
vorbisdec=0

[sw_video_decoder]
avdec_h264=0
avdec_vp8=0
avdec_vp9=0

[default_sink]
video=omx_lxvideosink
audio=audiosink

[decode]
in_size=128
out_size=128

[debug]
GST_TRACERS=
PMLOG_DEBUG_KLASS=Decoder&Codec,Audio&Sink,Video&Sink
PMLOG_DEBUG_ELEMENT=streamsynchronizer,multiqueue,decproxy,decbridge
PMLOG_DEBUG_EVENT=stream-start,caps,flush-start,flush-stop,seek,stream-collection
DEBUG_MODE=disable
GST_DEBUG=5
GST_DEBUG_FILE=/tmp/gst.log
GST_DEBUG_FILE_MAX_COUNT=2
GST_DEBUG_FILE_OVERWRITE=disable
GST_DEBUG_DUMP_DOT_DIR=/tmp
GST_DEBUG_NO_COLOR=1
DOT_GRAPH_TIMEOUT=0