Hardware Transcoding stopped working

numetaler · 2025-08-12T09:53:24+00:00

Hello everyone, for some time now, I have been experiencing issues with hardware transcoding. I am uncertain if this is the appropriate forum, as I am using...

numetaler

back again from testing.

i startet a container with this commit: 730718c. H265 and H264 transcoding work just fine here.

numetaler

testet with Build: 4.3-2430_gda9fa6032 and it worked just fine on this version

ukn_unknown

If this commit was working:

is good news ... because the big changes are before.
I was wrong on my estimation ... (time fly ... ): Commits on May 19, 2025 --> this is the major change.
The usual suspects:

make sure that container and user has access rights to access hw accelerator.
make sure tvh was compiled with the proper components selected (BTW: you didn't sent me:

can you copy the text from right side of build number from About page, after you click 'Toggle details'?

let's recap the changes that I think are affecting transcoding:

There is a setting: Hardware Acceleration Details --> can you check how many options you have available? that will tell me indirectly if vaapi was compiled.

Regarding a new HW ... we need to discuss more on what is your goal for transcoding. Why do you want to transcode ?How many concurrent transcoding streams? What resolution (IN and OUT) and frame rate? Are you picky on quality of the transcoding 🙂 (this makes a big difference)? Are you constrained in bandwidth ? how much bit rate can you achieve?

numetaler

sorry i got you wrong. thougt you just need the build number 🙂

BTW: you didn't sent me:

Configure arguments:
--disable-ffmpeg_static --disable-libfdkaac_static --disable-libtheora_static --disable-libopus_static --disable-libvorbis_static --disable-libvpx_static --disable-libx264_static --disable-libx265_static --disable-libfdkaac --enable-libopus --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --disable-avahi --disable-dbus_1 --disable-bintray_cache --disable-execinfo --disable-hdhomerun_static --enable-hdhomerun_client --enable-libav --enable-pngquant --enable-trace --enable-vaapi --infodir=/usr/share/info --localstatedir=/var --mandir=/usr/share/man --prefix=/usr --python=python3 --sysconfdir=/config

Compiler:
Using C compiler: cc
Using LD flags: -lhdhomerun -ldvbcsa
Build for arch: x86_64

Binaries:
Using PYTHON: python3
Using GZIP: gzip
Using BZIP2: bzip2

Options:
pie yes
ccdebug no
cardclient yes
cwc yes
cccam yes
capmt yes
constcw yes
linuxdvb yes
satip_server yes
satip_client yes
hdhomerun_client yes
hdhomerun_server yes
hdhomerun_static no
iptv yes
tsfile yes
dvbscan yes
timeshift yes
trace yes
avahi no
zlib yes
libav yes
ffmpeg_static no
libx264 yes
libx264_static no
libx265 yes
libx265_static no
libvpx yes
libvpx_static no
libtheora yes
libtheora_static no
libvorbis yes
libvorbis_static no
libfdkaac no
libfdkaac_static no
libopus yes
libopus_static no
nvenc no
vaapi yes
mmal no
omx no
inotify yes
epoll yes
pcre no
pcre2 yes
uriparser yes
ccache no
tvhcsa yes
bundle no
pngquant yes
kqueue no
dbus_1 no
android no
gtimer_check no
slow_memoryinfo no
libsystemd_daemon no
pcloud_cache yes
ddci yes
cclang_threadsan no
gperftools no
execinfo no
mmx yes
sse2 yes
W_unused_result yes
f_stack_protector yes
f_stack_protector_strong yes
f_stack_check yes
f_PIE yes
strlcat yes
strlcpy yes
fdatasync yes
getloadavg yes
atomic32 yes
atomic64 yes
atomic_time_t yes
atomic_ptr yes
bitops64 yes
qsort_r yes
time_ld yes
stime yes
gmtoff yes
recvmmsg yes
sendmmsg yes
gnu_libiconv yes
libiconv yes
ifnames yes
py_gzip yes
bin_pkg_config yes
bin_xgettext yes
bin_msgmerge yes
bin_gzip yes
bin_bzip2 yes
ssl yes
linuxdvbapi yes
linuxdvb_ca yes
libhdhomerun yes
upnp yes
hwaccels yes
inotify_h yes
inotify_init1 yes
dvbcsa yes
epoll_create1 yes
mpegts yes
mpegts_dvb yes

Packages:
openssl 3.3.4
zlib 1.3.1
libpcre2-8 10.43
liburiparser 0.9.8
libavfilter 7.110.100
libswresample 3.9.100
libswscale 5.9.100
libavformat 58.76.100
libavcodec 58.134.100
libavutil 56.70.100
libva 1.21.0
libva-drm 1.21.0

Installation paths:
Prefix: /usr
Binaries: ${prefix}/bin
Libraries: ${prefix}/lib
Data files: ${prefix}/share
Man pages: /usr/share/man

As i understand docker containers, someone builds them and changes the "app" inside the container, so that i just have to switch the container image and the whole "app" is updated. I have the container running with high priority what means it has root acces... (i know, shame on me)
so imho either the one who builds the app in the container (linuxservers.io) made some mistake or something in the new 3 commits is not compatible with my setup, i'm thinking.

The goal of the whole transcoding is that i sometimes work offshore and like to watch german tv in my spare time. bandwith is a problem in this case. so i always reduce resolution until i can watch somehow fluid.

the second goal is my father in law has some trouble with his own dish related to some strange interference. so he connects from time to time to my network via tailscale and can access my dish 🙂 in this cas im not to limited with bandwith. usually it works without transcoding, but i set his account to 720 wich works pretty much all the time

maximum streams i have is 2, but normal its just one

numetaler

forgot to mention: Resolution IN is up to 1080 what HD providers transmit and OUT is depending on my use case. either its 720 or i play with resolution and bitrate etc. until it works on that specific place. framerate isn't something i'd thougt of a lot, so it would normaly be 25 frames?

on the hardware acceleration details option i have auto (recommended) and prioritize vaapi. i tried both and both were not working

ukn_unknown

numetaler
tvh is compiled with vaapi and libav ... so it should work.

Now I have the big picture. I have some recommendation related to settings ... that should be discussed at some point.
Related to PC I don't think N100 is the best option ... in my opinion. Of course this is my personal opinion ... I will try to provide the information and you can decide for your self.
Let's start with some documentation:
https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video --> here is a good starting point to give you a big picture
Note: VAAPI is implemented using a subset of features from QSV (Intel Quick Sync Video).
Try to stick with ****lake that you see in that list ... all the others are refresh (low cost) versions.
Newer generations have better implementation and will generate better quality (for the same bitrate).
I recommend you to check the CPU (before buying) on https://www.cpu-monkey.com/en/ to see the GPU characteristics.
My personal observation was that CUs / Shader are a good indication of the quality of the video encoding (especially with QSV); higher is better.
If you search in Intel site: as example https://www.intel.com/content/www/us/en/products/sku/231803/intel-processor-n100-6m-cache-up-to-3-40-ghz/specifications.html you can look at GPU Specifications / Execution Units
Another important parameter that I found that correlate with quality is frequency range for iGPU: higher is better.

The lowest level of CPU I played with (I am going to skip raspberry pi 4) was https://www.intel.com/content/www/us/en/products/sku/93361/intel-atom-x5z8350-processor-2m-cache-up-to-1-92-ghz/specifications.html
Note: max GPU freq 500M and E.U. 12
The middle level is J4125 https://www.intel.com/content/www/us/en/products/sku/197305/intel-celeron-processor-j4125-4m-cache-up-to-2-70-ghz/specifications.html
Note: max GPU freq 750M and E.U. 12
J series is significantly better (has support for HEVC encoding).
The middle upper is Celeron 6305: https://www.intel.com/content/www/us/en/products/sku/208646/intel-celeron-6305-processor-4m-cache-1-80-ghz-with-ipu/specifications.html
Note: max GPU freq 1250M and E.U. 48
This option has a biffed up GPU ... CPU not so much. But if your target is HW encoding CPU is not required (AAC encoding is not a problem for any CPU this days). --> recommended for good quality/price
upper is i5-1240P: https://www.intel.com/content/www/us/en/products/sku/132221/intel-core-i51240p-processor-12m-cache-up-to-4-40-ghz/specifications.html
Note: max GPU freq 1300M and E.U. 80
This option is strong on GPU and CPU. Is at the boundary of being able to convert 2 stream 1080p -> 1080p H264 --> HEVC with B frame support in real time. I test it with QSV ... not VAAPI; but I am sure the comparison is close.

Now going to your actual CPU: https://www.intel.com/content/www/us/en/products/sku/95594/intel-celeron-processor-j3455-2m-cache-up-to-2-30-ghz/specifications.html
Note: max GPU freq 750M and E.U. 12
It is in the same category with other Jxxxx above; and I am tempted to say is in the same ballpark number with N100.
Note a small detail: N100 is alterlake-n (not alderlake): https://www.google.com/search?q=what+is+difference+from+alder+lake+and+alder+lake-N
I hope I didn't confuse you even more 🙂 ... let me know if you have any particular questions (or if you want my opinion on a particular CPU).

Now going back to your problem: Do you have the ability to test other containers in between? would help to narrow down ever further. Not being able to compile will hard for use to figure out what is the actual problem.
Can you copy the output of command vainfo -a in a text file and attached to your response?

numetaler

thank for your detailed detailed informations. i will work myself trough in the next time. thats a lot of work you put in there 👍️

i go on trying those containers one by one and tell you when the problem occurs

ukn_unknown

numetaler
Can you copy the output of command vainfo -a in a text file and attached to your response?

numetaler

if i connect with ssh to my synology the command gives me an error:

Trying display: drm
error: failed to initialize display

Makes sense, since there is no Display connected. i try to check inside the container

edit:
inside the container i cannot use this command

numetaler

i checked if my gpu is available in the container, and i looks like it is:

Alex@DiskStation:~$ sudo docker exec -it tvheadend_transcode ls -l /dev/dri
total 0
crw------- 1 root root 2445901728, 32552 Aug 14 05:46 card0
crw-rw---- 1 root videoe8bjvu11 2445901728, 32552 Aug 14 05:46 renderD128

numetaler

the next container i can test includes the commits b9d34f9 and 0af87f1 wich results in:
Build: 4.3-2432_g0af87f13f (2025-07-26T15:51:23+0000)

and here it stopped working... so it could be either one of those commits
VLC says the format i set (1280:720) but image is frozen from the start and i don't even have sound.

ukn_unknown

numetaler
To narrow down fully you need a container that includes the commits b9d34f9 --> frankly is hard for me to foreseen that changes from this commit might generate that behavior.
Can you remove (for testing only) the resize (instead of "Down (only)" select "Up & Down") ?

Trying display: drm
error: failed to initialize display

This is expected if you don't have monitor ... I need the rest of the text. Is strange that is trying to use 'drm' 🙁 . Should be something like ... Check if your versions of libva, vaapi and driver version are close to mine.

Trying display: wayland Trying display: x11 error: can't connect to X server! Trying display: drm libva info: VA-API version 1.18.0 libva info: Trying to open /usr/lib/x86_64-linux-gnu/dri/iHD_drv_video.so libva info: Found init function __vaDriverInit_1_18 libva info: va_openDriver() returns 0 vainfo: VA-API version: 1.18 (libva 2.18.0) vainfo: Driver version: Intel iHD driver for Intel(R) Gen Graphics - 23.2.1 () vainfo: Supported profile and entrypoints

numetaler

I think idon't get vainfo output because my synology is a nas without display connector. I think i can't get more information.

Regarding the docker i test one with the commit you said

numetaler

ok, so i can just download the container wich includes the two commits b9d34f9 and 0af87f1. unfortunately linuxserver did no update inbetween this two commits...
i try to install vaainfo inside the container. maybe this works.

edit:

it did 🙂
here is the output:

root@tvheadend:/#vainfo
Trying display: wayland
error: XDG_RUNTIME_DIR is invalid or not set in the environment.
Trying display: x11
error: can't connect to X server!
Trying display: drm
libva info: VA-API version 1.21.0
libva info: Trying to open /usr/lib/dri/iHD_drv_video.so
libva info: Found init function __vaDriverInit_1_21
libva info: va_openDriver() returns 0
vainfo: VA-API version: 1.21 (libva 2.21.0)
vainfo: Driver version: Intel iHD driver for Intel(R) Gen Graphics - 23.4.3 ()
vainfo: Supported profile and entrypoints
VAProfileNone : VAEntrypointVideoProc
VAProfileNone : VAEntrypointStats
VAProfileMPEG2Simple : VAEntrypointVLD
VAProfileMPEG2Main : VAEntrypointVLD
VAProfileH264Main : VAEntrypointVLD
VAProfileH264Main : VAEntrypointEncSlice
VAProfileH264Main : VAEntrypointFEI
VAProfileH264Main : VAEntrypointEncSliceLP
VAProfileH264High : VAEntrypointVLD
VAProfileH264High : VAEntrypointEncSlice
VAProfileH264High : VAEntrypointFEI
VAProfileH264High : VAEntrypointEncSliceLP
VAProfileVC1Simple : VAEntrypointVLD
VAProfileVC1Main : VAEntrypointVLD
VAProfileVC1Advanced : VAEntrypointVLD
VAProfileJPEGBaseline : VAEntrypointVLD
VAProfileJPEGBaseline : VAEntrypointEncPicture
VAProfileH264ConstrainedBaseline: VAEntrypointVLD
VAProfileH264ConstrainedBaseline: VAEntrypointEncSlice
VAProfileH264ConstrainedBaseline: VAEntrypointFEI
VAProfileH264ConstrainedBaseline: VAEntrypointEncSliceLP
VAProfileVP8Version0_3 : VAEntrypointVLD
VAProfileVP8Version0_3 : VAEntrypointEncSlice
VAProfileHEVCMain : VAEntrypointVLD
VAProfileHEVCMain : VAEntrypointEncSlice
VAProfileHEVCMain : VAEntrypointFEI
VAProfileHEVCMain10 : VAEntrypointVLD
VAProfileVP9Profile0 : VAEntrypointVLD

this is from the container with both commits. from where transcoding isn't working anymore

ukn_unknown

numetaler
Based on this info container is updated 🙁 let's try to capture some logs.
On the web interface: Configuration / Debugging / Configuration

I am not sure how container will affect the file system ... do you have /tmp folder? adjust that to fit the container.

For codec profile use the settings:

for stream profile use:

In order to acquire a small sample of logs, after you press Save button (on first picture with debug settings); you start playing imediately on Kodi one channel. After failure you need to delete the first settings from Debug "/tmp/tvheadend" and press Save again (that will stop the logging acquisition.
After that attach the file on this thread.

numetaler

hello, i testet now like you said with kodi... what can i say... with kodi it works. so the real problem must be in the android TVHclient-App, or android VLC or android itself... who knows... i am very sorry that i took your time.
There is just one minor problem. The sound is about 1 second out of sync with the image during transcoding. Can this be improved, or should I compensate for the delay in Kodi?

numetaler

couldn't edit my last post:

hello, i testet now like you said with kodi... what can i say... with kodi it works. so the real problem must be in the android TVHclient-App, or android VLC or android itself... who knows...
So i testet to open a transcoded stream directly with vlc on my pi5. Same problem like on TVHClient-App. Stream starts, picture frozen and no sound. if i use something else than matroska(mkv) built in it gets me immediately an error in vlc.
There is just one minor problem when using Kodi. The sound is about 1 second out of sync with the image during transcoding. Can this be improved, or should I compensate for the delay in Kodi?

i think it could be that my problem with not starting streams at my father in laws place with kodi, was related to bad/slow connection via tailscale... today i do some testing when i'm at his place.

to test things at home i set up an hotspot and connected my rpi5 with normal wireguard to my homenetwork and startet streaming in kodi. Except for the audio delay, it worked well, but direct in VLC its not working.

i tried to get logs as you said in /tmp. but i didn't find out yet how to achive this in a container. ill get back to you as soon as i managed to log something

numetaler

i testet again with the older container where everything was working fine and there is no sync problem in kodi. VLC is Working fine on this build as well

ukn_unknown

numetaler

The sound is about 1 second out of sync with the image during transcoding. Can this be improved, or should I compensate for the delay in Kodi?

i testet again with the older container where everything was working fine and there is no sync problem in kodi. VLC is Working fine on this build as well

Interesting ... I don't have this problem. Delay is constant? or is variable based on: how close are you from source, is accessed directly or through VPN? Can you perform some tests on local network (in order to remove the VPN from picture)? Another thing to look for is how much CPU is used when you start one container (that works) and second container (that doesn't work). I experienced this delay on RPI4 when I tried to transcode video with large resolution.
Another interesting test is to reduce the resolution (a lot) to confirm if the traffic of information is the problem. Instead of 720 can you set a small value ... like 240?
For RPI 5: can you flash something light like LibreELEC on the SDCard?

i think it could be that my problem with not starting streams at my father in laws place with kodi, was related to bad/slow connection via tailscale... today i do some testing when i'm at his place.

You can use iperf3 to test the throughput before testing video. If you have large variation in throughput this system is not intended to adjust dynamically (like Neflix) 🙁 ... so will fail.

numetaler

im busy today, maybe i have time tomorrow to do more testing. i have a up to date libreelec install on a pi4 and i already tested transcoding in my home network. had the same delay witch is constant the whole time