codec 422 support

1st Official Post

    here i attached record sample 422 codec file, i'm using 007 s905, if i activate hw decoder, the screen is black, if i disable it, the picture stutter, maybe kszaq can do something

    Edited once, last by lrusak (October 1, 2016 at 6:30 PM).

    High 4:2:2 Profile - as an extension of Hi10p profile - is not supported by Amlogic HW decoder (nor any known cosumer HW decoder AFAIK), it has to be software-decoded. S905 may be not powerful enough to do software decoding of 1080p 4:2:2 video.

    Fallback to software decoding for High 4:2:2 profile is already covered in my development builds: projects/S*05: add more unsupported H264 encodings to HW decoding bla… · kszaq/LibreELEC.tv@448424a · GitHub

    To sum up, you are not able to play 1080p High 4:2:2 videos with S905.

    Quote from kszaq


    High 4:2:2 Profile - as an extension of Hi10p profile - is not supported by Amlogic HW decoder (nor any known cosumer HW decoder AFAIK), it has to be software-decoded. S905 may be not powerful enough to do software decoding of 1080p 4:2:2 video.

    Fallback to software decoding for High 4:2:2 profile is already covered in my development builds: projects/S*05: add more unsupported H264 encodings to HW decoding bla… · kszaq/LibreELEC.tv@448424a · GitHub

    To sum up, you are not able to play 1080p High 4:2:2 videos with S905.

    ok kszaq thank you for explanation,
    Klojum thanks for reminding me, i though by providing file instead of log, dev can see directly what's really happening not imagining what was happening

    4:2:2 H264 is software decode-only on pretty much every consumer platform (including x86). I have a Haswell i5 NUC that can do a reasonable job with 1080i25 (aka 1080/50i) 4:2:2 H264 at 38Mbs including a YADIF 2x deinterlace. (It used to struggle until ffmpeg improvements in H264 multithreading were made)

    Quote from noggin


    4:2:2 H264 is software decode-only on pretty much every consumer platform (including x86). I have a Haswell i5 NUC that can do a reasonable job with 1080i25 (aka 1080/50i) 4:2:2 H264 at 38Mbs including a YADIF 2x deinterlace. (It used to struggle until ffmpeg improvements in H264 multithreading were made)

    wow, so 422 > 4k? s905 could decode x265 pretty smooth, though it was born after 422 and hi10p, or maybe hardware producer just ignore it because not so popular among tv content standard

    Quoting Wiki:

    Quote


    High 4:2:2 Profile (Hi422P, 122) Primarily targeting professional applications that use interlaced video, this profile builds on top of the High 10 Profile, adding support for the 4:2:2 chroma subsampling format while using up to 10 bits per sample of decoded picture precision.

    That's why you don't see it in consumer-aimed devices.

    Quote from kszaq

    High 4:2:2 Profile - as an extension of Hi10p profile - is not supported by Amlogic HW decoder (nor any known cosumer HW decoder AFAIK), it has to be software-decoded. S905 may be not powerful enough to do software decoding of 1080p 4:2:2 video.

    Fallback to software decoding for High 4:2:2 profile is already covered in my development builds: projects/S*05: add more unsupported H264 encodings to HW decoding bla… · kszaq/LibreELEC.tv@448424a · GitHub

    To sum up, you are not able to play 1080p High 4:2:2 videos with S905.

    Which tv box with Amg soc currently supports 4: 2: 2 H264 or H265 videos either by hardware or software? S922x?

    i tried a rpi4 and it doesn't work with 4: 2: 2 H264 or H265 videos

    Quote from espaun206

    Which tv box with Amg soc currently supports 4: 2: 2 H264 or H265 videos either by hardware or software? S922x?

    i tried a rpi4 and it doesn't work with 4: 2: 2 H264 or H265 videos

    Very few boxes support 4:2:2 video as it isn't a consumer format (DVD, DVB TV broadcasts, Blu-ray, UHD Blu-ray, Netflix, Prime etc. are all 4:2:0) so there is no reason to implement it in chipsets aimed at consumer devices.

    4:2:2 h.264/h.265 is only used by broadcasters on contribution circuits - not final-leg distribution - so unless you are building a box for feed hunters (a small market) 4:2:2 isn't really a 'must have' feature.

    None of the AMLogic chipsets that I am aware of support 4:2:2 hardware decode for this reason - so you need a box fast enough to decode it (and if it's interlaced also YADIF or W3DIF 2x deinterlace it) with CPU power.

    The only ARM media player platform that I know that can currently do software decode (and deinterlace) of 1080i25 for MPEG2 and h.264 4:2:2 is the Apple TV 4K (the ARM SoC in that is a beast)

    The other BIG advantage of the Apple TV 4K is that it has hardware acceleration support for 4:4:4 and 4:2:2 h.265/HEVC decode - because Apple use that codec for their Airplay/Sidecar iPad dual display function which compresses desktop video to h.265 for carriage over WiFi or Lightning/USB Type-C connection (to avoid reducing the chroma res to 4:2:0 and it all going smeary when you use your iPad as a second display) The Apple TV also has that functionality. I've played 2160p50 4:2:2 h.265/HEVC on the Apple TV in mrMC with very low CPU (but it was still not perfect because of some A/V sync issues)

    If you want MPEG2 and h.264 4:2:2 with LibreElec then a decent Intel or AMD solution is probably your best bet - I used to use a Haswell i5 NUC to play 4:2:2 stuff and it coped - just - once multithreaded software decode of h.264 was implemented in ffmpeg. However the LibreElec implementation seemed to do a 4:2:2 to 4:2:0 conversion without interlaced aware chroma decode/conversion so you had saturated areas deinterlaced with p25 rather than p50 motion (a known issue in ffmpeg)

    Edited once, last by noggin (October 24, 2020 at 9:26 AM).