DNLA much better image quality than AirPlay

Discussion in 'Apple TV and Home Theater' started by hagar, Jan 29, 2016.

  1. hagar, Jan 29, 2016
    Last edited: Jan 29, 2016

    hagar macrumors 6502a

    Joined:
    Jan 19, 2008
    #1
    Hi, when I stream videos to my Samsung smart TV, the image quality is much better when I use DNLA rather than AirPlay. For instance: I shot a video with my iPhone 6S. Streaming it over Airplay from the iPhone to ATV was fine. Then, I installed some crappy Samsung app and used that to stream the same video over DNLA and the result blew me away. Much better image quality. However, the video stuttered.

    Should image quality be the same and is this possibly caused by other factors (such as the Wifi network, causing Airplay to downgrade image quality in favour if smooth playback) ?

    Or is Airplay technically inferior to DNLA and should it be avoided?

    (I previously had noticed this with the 2nd generation ATV, assuming this was caused by the lack of HD support. But now i have the 4th generation and image quality has not improved)
     
  2. Alrescha macrumors 68020

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    Jan 1, 2008
    #2
    It depends on what you are doing. If by Airplay you mean Airplay Display, then OS X is taking your video, decoding it for your display, then *re-encoding* it to send it to your Apple TV. It is not an optimal situation.

    For the best experience you would give the video to iTunes, and then either stream it from there to the Apple TV or let the Apple TV play it via Home Sharing. In that case you would get the most efficient processing and the best presentation - equal to or better than DNLA.

    A.
     
  3. hagar thread starter macrumors 6502a

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    Jan 19, 2008
    #3
    Hi, Alrescha, thanks for your reply. I'm just streaming video from my iPhone 6S. Not using mirroring to avoid the re-encoding problem.

    That's why I'm surprised by what I'm seeing: I would expect that streaming a HD-video over Airplay would playback the video in HD on Apple TV. If Samsung can do it with their iOS app, Apple should also be able to do it over Airplay?
     
  4. benjitek macrumors 6502a

    benjitek

    Joined:
    Sep 23, 2012
    #4
    I have a mixed bag of streaming options. iPhone 6S Plus, Microsoft Surface Pro 2, and MacBook Pro 13" Retina. If I need to 'cast' something (AirPlay not-mirrored), the iPhone 6S Plus works the best. Amazon Video is great that way, with my 6S+ being a seconds screen of 'X-Ray' info. If I AirPlay-cast from Netflix, Hulu, or Amazon from my iPhone, I get HD video and my iPhone turns in an ultra-deluxe remote. DLNA with my Surface Pro 2 (upgraded to Windows 10, clean install) is not as buttery-smooth as AirPlay casting. DLNA is a fussy option that offers nowhere near the feature-set of AirPlay-cast o_O

    It's always tempting to blame service or providers, but maybe look at your network setup -- what band are you connecting to your router on? Maybe it's a congested channel -- have you looked at that? There are some great apps for measuring channel utilization for your location, I use WiFi Explorer myself -- though I don't understand much of what it does, it tells me which channel(s) are best and I've got nothing near the issues you describe :)

    Screenshot of Google Chrome (1-29-16, 8-31-30 PM).png
     
  5. hagar thread starter macrumors 6502a

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    Jan 19, 2008
    #5
    Hi, Thanks, I already did something similar and use a good Wifi channel. But I just tried to connect with an Ethernet cable and then streamed some videos from my iPhone 6S:
    - plugged into the Smart TV: perfect image, smooth playback over DNLA with the Samsung Smart View app (whereas it was stuttering over Wifi)
    - plugged to the Apple TV: clearly a non-HD image but smooth playback with Airplay (no difference between Ethernet and Wifi)

    I just don't think Airplay is capable of HD when streaming from Mac or iOS in my scenario. Weird. Maybe it's a bug?
     
  6. benjitek macrumors 6502a

    benjitek

    Joined:
    Sep 23, 2012
    #6
    You never know, could be -- but if it is, it's one of those bugs that only effects 'a small number of users' -- doesn't happen to me, great HD via AirPlay casting and my iPhone 6S Plus. Just make sure you're AirPlay-casting and not using AirPlay Mirror...
     
  7. priitv8 macrumors 68020

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    Jan 13, 2011
    Location:
    Estonia
    #7
    Because iPhone produces video, whose bitrate exceeds aTV playback capabilities, I would not be surprised at all, if Apple decided to recode it on the fly while airplaying. Here is example from one FullHD and one 4K clip:
    Screen Shot 2016-01-30 at 11.20.25.PNG
     
  8. hagar thread starter macrumors 6502a

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    Jan 19, 2008
    #8
    @benjitek I have looked into this some more, and my image quality over Airplay is probably better dan 720p and most people probably assume they have "great" HD. I also did, as the image looks quite good. Until I experimented with DNLA. When I saw that image I was blown away by the vibrant colours and detail.

    @priitv8 I think you're right. Video is probably recoded on the fly. I just added my iPhone6S video to iTunes and accessed it via 'Computers' on ATV (both Mac and ATV connected by cable) and the results are the same as streaming directly from the iPhone. More 'washed out'.

    So yeah, better image over DNLA than Airplay. Pretty disappointing.
     
  9. waw74 macrumors 68030

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    May 27, 2008
    #9
    so anytime you watch from the aTV (either airplay or stream from iTunes) it's "washed out", but when you watch directly from the television using an app, it's fine?

    is it possible your TV has different picture modes for different sources? that automatically switch?
    or a setting on the HDMI port (either on the aTV or the television) that don't apply to something internal on the television.

    what's the resolution of your TV?
    4K? Anything the aTV plays will be downscaled to 1080, but the TV can play it in it's native 4K.
    1080? it's possible the scaler in your TV is just better than the one in the aTV.

    try changing the record quality on your iPhone to 1080, and see if you still see a difference between the 2 playback methods.
     
  10. hagar thread starter macrumors 6502a

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    Jan 19, 2008
    #10
    Hi, the video shot on the iPhone 6S is 1080. My TV is a Samsung Smart TV from 2014 (1080 HD)

    I checked the profiles, and you are right: the TV switches to far more "dynamic" profile and a higher backlight, which explains the bright colours. The weird thing is, I cannot choose that profile when switching to Apple TV. Maybe Samsung does not like Apple ;-)

    But the image is still less sharp. I think the videos are indeed re-encoded on the fly causing loss of sharpness.
     
  11. Alrescha macrumors 68020

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    Jan 1, 2008
    #11
    There is no re-encoding of video when you are watching video on your Apple TV using the Computers tab (the CPU usage required on the iTunes side would be a dead giveaway).

    A.
     
  12. hagar thread starter macrumors 6502a

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    Jan 19, 2008
    #12
    Why? Airplay Mirroring re-encoding is also done on-chip, no CPU spike there.
     
  13. Alrescha macrumors 68020

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    Jan 1, 2008
    #13
    Well, I'm not aware of hardware encoding assists on the Mac, but they might exist. In any case, it is easy to demonstrate - firing up Airplay mirroring and playing a movie visibly bumps up both kernel_task and WindowServer. No such event occurs when playing a movie via the Computers tab on the Apple TV.

    A.
     
  14. matrix07 macrumors 68040

    matrix07

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    Jun 24, 2010
    #14
    People normally think over-processed images to be sharper = superior quality when most of the time it's just not.
     
  15. hagar thread starter macrumors 6502a

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    Jan 19, 2008
    #15
    Never heard of that.

    I can clearly see much more detail in the videos streamed over DNLA. The fact that the video stutters, seems to be an indication the bit rate is much higher. When streaming over Airplay, the video does not stutter.
     
  16. benjitek macrumors 6502a

    benjitek

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    Sep 23, 2012
    #16
    Sorry it's not working out for you, on my system AirPlay picture quality mirrors DLNA. AirPlay is more consistent though, and adds a lot of functionality DLNA doesn't. Guess about all you can do is try again with each tvOS update and see if it all works better with the way you have things configured. Or, if the disappointment level is too high, return it :(
     
  17. matrix07 macrumors 68040

    matrix07

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    Jun 24, 2010
    #17
    Subjective evidence, which means nothing. The fact that you're fixated to prove the "superior quality" of DLNA will easily cloud your judgement. It's easy to prove Apple converting video on AirPlay or not though. Just install Beamer on your Mac. On Preference/Playback check h.264 passthrough then AirPlay the video through Beamer. If the quality is the same as AirPlay from iPhone, then there's no conversion, and the difference you saw is just the result of that "Dynamic" profile on your TV, which you seem to personally prefer. Nothing's wrong with that.
     

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