Video playback? speed problems

S.L.P. image questions, stereoscopic video livestream and recording, stereoscopic photo capture etc.
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peterfiabigron
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Joined: Fri Sep 16, 2022 8:19 am

Video playback? speed problems

Post by peterfiabigron »

Hello,

I have some problems with video capturing.
My stereo videos are faster in playback than normal, something between 1,5x - 2x speed. Could you help with it? What could have caused this?

Thanks!
Gábor

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Realizator
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Re: Video playback? speed problems

Post by Realizator »

Hello Gábor,

This usually happens when you are trying to play the raw h264 video, but not the video packed to the container (like mp4).

Could you please share your video settings with me? The resolution, frame rate, and video format.

Also, could you please clarify the version of the SLP2 you are using?
Eugene a.k.a. Realizator

peterfiabigron
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Joined: Fri Sep 16, 2022 8:19 am

Re: Video playback? speed problems

Post by peterfiabigron »

Dear Eugene,

I am using firmware version 0.15.3
RPI CM4 Rev1

My video settings:
1920x1080
30fps
5000000bitrate
H264 settings are empty
Transport: udp
Mjpeg streem on host enabled (i disabled it because it made preview disappear on phone, which is connected as wifi router, via stereopi's ip address)

Currently, i am using mkv format, but it was the same with mp4 as well. From SDcard DCIM folder i download the ...h264.mkv file from the two (not the ...h264 version)
But as i have checked, for mkv my phone adds the following ending when i download the file: h264.mkv.webm. it is not present for mp4 videos but the phenomenon is the same

In image settings everything is auto except EV=0, image effect and metering mode is empty.

Thank you for your time on this!
Gábor

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Re: Video playback? speed problems

Post by Realizator »

Hi Gábor,

Thank you for the details!

I will be pleased if you can record a tiny test video (like 10 seconds) and share it with me for analysis. I'm curious to find the issue!
Eugene a.k.a. Realizator

peterfiabigron
Posts: 14
Joined: Fri Sep 16, 2022 8:19 am

Re: Video playback? speed problems

Post by peterfiabigron »

Dear Eugene,

Thank you for your tireless support!
https://drive.google.com/file/d/1uRvbyn ... sp=sharing
On the above link I shared a test video.

Unfortunately, since then I realised that on the upper right corner I sometimes have "WLAN ~50-64C health bad" warning. Sometimes health is ok. I usually use my smartphone as wifirouter to control the device, and connect the phone also as power source through type-c usb. I have the issue that sometimes both the device and the control panel froze, sometimes only the control panel on phone e.g. during recording. Other times it records and works fine. Do you have any idea what can be wrong? As far as I am aware, I followed the wiki instructions.

Thank you!
Gábor

peterfiabigron
Posts: 14
Joined: Fri Sep 16, 2022 8:19 am

Re: Video playback? speed problems

Post by peterfiabigron »

Dear Realizator,

Did you manage to check the video speed problem?
I made the setup as it is described in wiki and I have this problem, that the video speed is not normal. Sometimes the device even freeze during video recording (maybe especially when I increase bitrate from 100000 to 300000) or when I go to device settings. The latest update does not work at all for me*.
I share another video which might better suited to show problem:
https://drive.google.com/file/d/1FKZdIh ... sp=sharing
Is it caused by lack of processing power/memory or something else?
I generally use my android smartphone's hotspot to control stereopiV2

An other interesting thing is that when I access MicroSD data to download pictures and videos and I return to the starting screen, I see some playback of the last video or of the time while I was in MicroSD download window.

*stereopi.local dice
Probabily a network error, is the server down?
Faild to fetch

Could you help me, I would really like to use this device. Thansk!

Blinky
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Joined: Wed May 01, 2019 11:18 pm

Re: Video playback? speed problems

Post by Blinky »

The stereopi needs a lot of power. Are you powering it from your phone while your phone manages a few other things? If so, a separate power bank for the stereopi might solve your problem.

Regards

peterfiabigron
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Joined: Fri Sep 16, 2022 8:19 am

Re: Video playback? speed problems

Post by peterfiabigron »

Hi Blinky,

Thanks for the hint. I tried it out (I powered it from electric socket with a 3A phone charger) and it improved the freezing situation, it is much better now, but not perfect (meaning that after a while it freezes yet sometimes, but I think I can live with that for now).
Meanwhile, I've found that the speed problem disappears when I use the factory resolution and framerate settings (1280x720, 30fps), but if I change any of them the recording speed changes. Interestingly, e.g. if I increase the framerate to 40fps, the video speed increases and the file size becomes smaller.
I use generally the most recent beta SLP2 version, but the same problems were there, when I used the out of the box version on SDcard.
Regarding the SLP2 update files, the wifi connection (AP and/or WLAN) works on the earliest version, but does not work for me with the newest update. Do anyone have all the versions of update files (from oldest to most recent one)? Is it just me, who have these kind of problems? Should I worry that maybe the problem is on my side, am I doing somthing in a wrong way?

Blinky
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Joined: Wed May 01, 2019 11:18 pm

Re: Video playback? speed problems

Post by Blinky »

My guess to the changing the resolution would be to also change the bitrate. But it is just a guess.

As to the latest SLP2 version not working, my latest adventures in that area led me to ditch the RPi imager and use Balena Etcher, and then go change the cosmos.conf file in the boot directory using rpiboot for the wireless configuration.

Good luck.

Blinky

peterfiabigron
Posts: 14
Joined: Fri Sep 16, 2022 8:19 am

Re: Video playback? speed problems

Post by peterfiabigron »

Hello,

THIS TIME I HAVE SOLUTIONS, not problems. ;)
I have been experimenting with the device powering it from an Adata 10000mAh powerbank. I found that it works quite well with the 0.15.3 slp2 update, without freezing. For now, i have not been checking in the checkbox of some additional possibilities, like video stab, decimate. Wireless connection is also working fine.
Regarding video speed problem i think changing bitrate has no effect on playback speed. I think that it is caused by the limited max capability of camera modul v2. It is capable only of 25fps on 1080p. If we try to go beyond 25fps the system compensates with playback speed. By increasing speed the 25fps will seems like e.g 30fps, but actually it remains 25fps, only the playback speed was increased which results in a 30 frame per "playback second".
If i use lower fps or higher fps with lower resolution than playback speed will be normal (if the camera module v2 can cope with the actual combination)
I will do more tests, but i hope that this solves the issues.
I hope there will be update soon which will let us be able to use camera module 3 with AF and HDR ( and hopefully it will be just the beginning)
I hope this report helps other users and Realisator as well.

Gábor

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Re: Video playback? speed problems

Post by Realizator »

Gábor thank you very much for this catch!

As for V3 - we are working on this. It's not that simple, since V3 camera is not supported by MMAL video subsystem we are using in SLP. It requires new libcamera-based video stack, which has no stereoscopic out of the box...
Eugene a.k.a. Realizator

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