Problems with rkmpv UHD h264 video playback

[danboid]

I have installed bionic-lxde-rock64-0.6.44-239-arm64 on my rock64 4GB but when I try to play a UHD h264 mp4 file using rkmpv I get very jerky video playback (maybe 2/3 fps) with lots of green horizontal lines obscuring the video. These same videos play fine under LibreELEC on my rock64 and with mpv under bionic (Ubuntu 18.04) amd64.

Here is the mediainfo output from one such video:

$ mediainfo 20180223_223347.mp4 
General
Complete name                            : 20180223_223347.mp4
Format                                   : MPEG-4
Format profile                           : Base Media / Version 2
Codec ID                                 : mp42 (isom/mp42)
File size                                : 598 MiB
Duration                                 : 1 min 44 s
Overall bit rate                         : 48.0 Mb/s
Performer                                : LGE
Encoded date                             : UTC 2018-02-23 22:35:33
Tagged date                              : UTC 2018-02-23 22:35:33
com.android.version                      : 6.0

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L5.1
Format settings                          : CABAC / 1 Ref Frames
Format settings, CABAC                   : Yes
Format settings, ReFrames                : 1 frame
Format settings, GOP                     : M=1, N=31
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 1 min 44 s
Source duration                          : 1 min 44 s
Bit rate                                 : 48.0 Mb/s
Width                                    : 3 840 pixels
Height                                   : 2 160 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Variable
Frame rate                               : 29.937 FPS
Minimum frame rate                       : 29.183 FPS
Maximum frame rate                       : 30.706 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.193
Stream size                              : 596 MiB (100%)
Source stream size                       : 596 MiB (100%)
Title                                    : VideoHandle
Language                                 : English
Encoded date                             : UTC 2018-02-23 22:35:33
Tagged date                              : UTC 2018-02-23 22:35:33
mdhd_Duration                            : 104152

Audio
ID                                       : 2
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : LC
Codec ID                                 : mp4a-40-2
Duration                                 : 1 min 44 s
Source duration                          : 1 min 44 s
Source_Duration_FirstFrame               : 71 ms
Bit rate mode                            : Constant
Bit rate                                 : 156 kb/s
Nominal bit rate                         : 96.0 kb/s
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 46.875 FPS (1024 SPF)
Compression mode                         : Lossy
Stream size                              : 1.94 MiB (0%)
Source stream size                       : 1.94 MiB (0%)
Title                                    : SoundHandle
Language                                 : English
Encoded date                             : UTC 2018-02-23 22:35:33
Tagged date                              : UTC 2018-02-23 22:35:33
mdhd_Duration                            : 104446

[danboid]

I have now tried playing the same video with rkmpv under bionic-lxde-rock64-0.7.8-1061-arm64.img with exactly the same results.

[danboid]

I can upload a sample video if required?

[xantoz]

Have you tried playing with the options --drm-osd-plane-id and --drm-video-plane-id and --drm-osd-size?

I don't have any 4K TV or monitor, so I cannot test, but according to @LongChair for 4K to work the drmprime video plane needs to be the primary plane _{(note that the video plane is only used during hwdec)}, and the OSD plane _{(note: this actually displays the video when not doing hwdec)} should be an overlay plane. In addition the OSD plane should be downsized using --drm-osd-size to something like 1920x1080, because otherwise it will be too slow to render or even fail to render at all.

Try something like: --drm-osd-plane-id=1 --drm-video-plane-id=0 --drm-osd-size=1920x1080

UPDATE:
I did some basic testing and found that you need to use mpv 0.29.0 to have --drm-osd-size (Bionic still ships 0.28.0). Also it still has the old option to control which planes to use --drm-overlay.
There were also some other commits by LongChair inbetween v0.28.0 and v0.29.0 which might or might not affect your results.

[danboid]

So its still not possible to achieve true 4K playback on the rock64 via mpv? I don't want to downscale to 1080 - it wasn't why I bought the device.

[xantoz]

It is possible, it just isn't neatly packaged yet. (If you wanted a painless experience, you bought the wrong device, I'm afraid. Also HDR support is still a ways away with Linux.).

It seems you misinterpreted the meaning of --drm-osd-size. When playing the video hardware decoded (which you will. The rock64 can't even do 1080p H264 software decoded) it will render at 4K (rendered by the VPU), only the OSD (rendered on an overlay by the GPU) is rendered at 1080p. The VPU can handle 4K, the GPU can't. The compositing hardware then stitches the video and overlay together into a 4K picture by scaling the OSD overlay up to size.

You'll have to build mpv 0.29 (check out https://github.com/avih/mpv-build) and then try using the command line options above. You'll need to make sure to have the right -dev packages and pass --enable-rkmpp in ffmpeg_options + a few other options I can't remember right now (I am away from home right now. I can create a mini-walkthrough of the entire process for you later if you want)

P.S. There actually exists a hack to do HDR passthrough using rockchip-specific (non-mainline) API:s on one of @LongChair's branches: https://github.com/LongChair/mpv/tree/rockchip-hdr?files=1 I haven't tested it for obvious reasons. It's a bit old however, you might want to rebase it. D.S.

P.P.S. If you want semi-painless 4K HDR passthrough playback currently the best, and much more expensive, device is a recent (previous to current-gen) Intel x86_64 with HDMI 2.0 support (varies with mobo) with Windows 10 (bound to work on mainline Linux eventually, though). Unfortunately that is the reality right now. D.D.S.

[danboid]

I'm not so much bothered about HDR support as I don't have a HDR display but I would be interested in building the latest mpv if that option will fix 4K playback so please do post your full mpv configure / compile time options please.

[danboid]

@xantoz

Which distro have you used to build mpv from git? I have tried under both ayufan's bionic and his stretch distros but in both cases I am unable to install the required packages due to clashes over libEGL.so.1 / libmali or, in the case of Ubuntu, I am unable to install the xorg dev packages due to a clash with libglvnd.

It would also be good to know exactly which ffmpeg options you use.

Thanks

[fcoulombe]

hi everyone, i'm also trying to playback a 4k video using latest bionic.

I installed the mali driver and using rkmpp, i seem to be able to get hardware decoding on 720p and i get the green lines mentioned by OP on the 4k videos.

i've managed to compile mpv 0.29 using mpv-build with ffmpeg_options
--enable-rkmpp
--enable-gpl
--enable-libx265
--enable-omx
--enable-libx264
--enable-libvpx
--enable-openal
--enable-version3
--enable-libdrm
--enable-ffplay

the thing i realized is that whether i use my custom built mpv 0.29 or the built in 0.28... i get software decoding for both 720p and 4k.

i'm guessing that i need to build rkmvp with my 0.29 mpv?

[fcoulombe]

also running rkmpv --drm-mode=21 your_4k_video.mp4 seems to work for 4k 30fps videos but is rather jerky on 60fps.

i don't yet understand what drm-mode 21 means but at least you don't get the green lines

[fcoulombe]

@danboid for the EGL clash, this is what i ended up understanding.

you get software rendering using mesa (libglvnd) by default but you can install the mali driver.
bother implementation (mali and mesa) provide an implementation of EGL and to get acceleration, you want to use the mali version.

to fix apt-get, i uninstalled mali (via dpkg purge). then i installed all the packages that i needed using mesa.
once i had everything, i force installed mali so that it overwrites the libEGL and then hardware acceleration seems to "work"

[danboid]

@fcoulombe

Thanks for sharing your build process / ffmpeg options.

I've not tried or seen anyone suggest using --drm-mode=21 yet - does this fix the green lines with the regular bionic 0.28 mpv build I wonder?

rkmpv is just a short shell script that calls mpv with a few specific (video output) options, its not a separate app.

I've not yet tried Armbian but I'm led to believe their kernel has some rockchip VPU support or at least it can be added on later.

[fcoulombe]

`cat /usr/local/bin/rkmpv
#!/bin/bash

export LD_LIBRARY_PATH=/usr/lib/aarch64-linux-gnu/gbm:/usr/lib/arm-linux-gnueabihf/gbm

exec mpv --vo=gpu --gpu-context=drm --hwdec=rkmpp "$@"
`

so running this on my built 0.29, i get:
`./mpv --vo=gpu --gpu-context=drm --hwdec=rkmpp ~/Downloads/burn4k.mp4
Error parsing option gpu-context (option parameter could not be parsed)
Setting commandline option --gpu-context=drm failed.

Exiting... (Fatal error)
`

using --drm-osd-plane-id=1 --drm-video-plane-id=0 --drm-osd-size=1920x1080 gives the same result

I found the --drm-mode tip here: https://forum.pine64.org/showthread.php?tid=6305

[danboid]

As per the script, you need to export that library path before you run mpv.

[fcoulombe]

i did, i just didn't put it in the snipet