PI4 and instant record.ts file problems
- maxi
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October 30, 2019 at 12:54 PM - Thread is Resolved
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It is mpeg-2 4:2:2. It will not be hardware decoded. I'm not sure pi4 is fast enough to software decode this.
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- Official Post
Download "handbrake" and transcode it to H264/H265 on the desktop machine. Time to transcode will be shorter than time looking for a Pi based solution that doesn't exist.
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That's a broadcaster uplink feed (31Mbs 4:2:2 h.264 video with 384k MP2 stereo audio) not aimed at consumers.
Consumer video (DVB/ATSC/ISDB, DVD, Blu-ray and UHD Blu-ray) is 4:2:0 - and that's what consumer devices have hardware acceleration for. As a result consumer devices - set top boxes, PC GPUs (**), ARM SoCs designed for consumer media playback etc. don't support it in hardware.
4:2:2 is only used in the broadcast/professional environment - and you need a broadcast/professional device to decode it with hardware acceleration (*).
For h.264 4:2:2 decode on a consumer device you need something with the CPU power to support software decoding (and probably software deinterlacing if the source material is 1080i25) This puts you in the Intel/AMD camp for realtime playback - not consumer ARM SoCs.
If you want to watch this stuff on a Pi - you will need to transcode to 4:2:0. If you want to retain chroma resolution then 4:2:2 1080i25 -> 4:2:0 1080p50 may be your best route. (ffmpeg with a -vf "w3fdif=complex:all" deinterlace is my go to for that when converting broadcast 4:2:2 sources - h.264/ProRes/DNX/AVCi100 etc. to h.264 or h.265 4:2:0 consumer video)
Personally I usually do this from the command line rather than in handbrake as I found handbrake would often deinterlace 1080i25 to 1080p25 not 1080p50 (and thus threw away 50% of the temporal - i.e. motion - resolution)
(*) When MPEG2 4:2:2 was used for satellite uplink, a couple of oddball consumer devices did have unadvertised 4:2:2 MPEG2 decoding (one version of the WDTV Live did it I discovered). However I've yet to find any consumer devices with unadvertised 4:2:2 h.264 decode.
(**) Some Non linear editors like FCPX, Prem Pro etc. will support GPU accelerated decode within their workflow - but this is bespoke within those packages.
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h.264 video
That sample is mpeg2
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Sorry - yes - people are absolutely right - it is MPEG2 not h.264 4:2:2. I can't think why I jumped to that conclusion as I opened it in MediaInfo. It's probably because I assumed it was recent - and I don't know of anyone in broadcast in the UK still using MPEG2 rather than h.264 for broadcast uplinks (as it's basically a waste of bandwidth to use MPEG2 these days)
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Hello,
Is it possible to improve the performance in order to be able to reproduce the type of video that I will put the link, I already talked about it in the post above.
Thanks
If you are talking about decoding and deinterlacing high bitrate 4:2:2 1080i25 MPEG2 (or h.264) on a Pi 4B - then no - I don't think it is currently possible.
The only ARM platform I know that can currently handle software decode and deinterlace of 4:2:2 1080i stuff is the Apple TV 4K. I've not seen any other ARM SoC handle it. (As an added benefit the ATV 4K has hardware accelerated decode of 4:2:2 and 4:4:4 HEVC/h.265 - as a side-effect of that codec being used for Mac Airplay desktop mirroring, though 4:2:2 MPEG2 and AVC/h.264 is done in software.)
It may be possible for the MPEG2 decode and deinterlace to be further optimised for the Pi to allow for it using techniques like GPU-assisted decode (rather than VPU hardware acceleration) - but for such a niche codec I'm not sure that the developers will have the inclination to do so.
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If you are talking about decoding and deinterlacing high bitrate 4:2:2 1080i25 MPEG2 (or h.264) on a Pi 4B - then no - I don't think it is currently possible.
The only ARM platform I know that can currently handle software decode and deinterlace of 4:2:2 1080i stuff is the Apple TV 4K. I've not seen any other ARM SoC handle it. (As an added benefit the ATV 4K has hardware accelerated decode of 4:2:2 and 4:4:4 HEVC/h.265 - as a side-effect of that codec being used for Mac Airplay desktop mirroring, though 4:2:2 MPEG2 and AVC/h.264 is done in software.)
It may be possible for the MPEG2 decode and deinterlace to be further optimised for the Pi to allow for it using techniques like GPU-assisted decode (rather than VPU hardware acceleration) - but for such a niche codec I'm not sure that the developers will have the inclination to do so.
Hello,
I noticed that you already have the new RPi5, is it possible for your friend to test the file to see how it behaves. At the moment the RPi4 can play this type of file, but it lacks fluidity, I think is a lack of processing power and there is no shortage of that in the new RPi5.
Thanks.
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That linked file was already asked about in another thread and it played fine on RPi5.
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That linked file was already asked about in another thread and it played fine on RPi5.
Yes, I mentioned it in another thread, but I think you ignored it, at least I didn't notice it.
Anyway, thank you.
