AirPlay and Fast Forward

So I’ve been digging into as many of the forum threads as I can find, as well as reviews and such, but I can’t seem to find the answer to one basic question. I use Apple TV in the house to 3 TVs. If I am using AirPlay from Tablo and do a standard fast forward or rewind, will I see the actual video on screen as the fast forward moves along, or does the screen go black? My understanding is that the “live fast forward” is a function of including HLS IFRAME coding in the HLS manifest, and given that Tablo now supports thumbs for Roku FFW, it seems like this should work on Apple TV without an issue and without requiring a “custom third party native app”. I can see the video preview during FFW and RW when watching a standard MP4 over the network… and Netflix can do “live FFW” as well. Any luck here?

What device are you using to AirPlay to your Apple TV? iPad or iPhone?

I’m an Apple developer. I can use either. I haven’t received my Tablo yet. I have several iPhones (of various models) and iPads (of various models).

From Apple’s documentation, all that is required for FFW and RW scrubbing is an IFRAME only playlist available in the master HLS manifest ->
“The #EXT-X-I-FRAMES-ONLY playlist can be used for preview images while scrubbing through the content.”

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I am an Apple developer as well and have the 4 tuner Tablo. There are separate apps for the iPhone and the iPad. The iPhone app was recently updated and has a scrub bar offering 4 seeds of scrubbing, Full, Half, Qtr and Fine. As you scrub the picture will jump along with your progress but the picture but will not produce the smooth scrolling that I have seen available in other apps. With the older iPad app there is one scrolling speed and it will show the picture where you started your scrub until such time as you lift your finger at which time it will jump to the new location.

I used a iPhone 6+ running iOS 8.4.1 and a iPad Air running iOS 8.4.1 to run the above test. I was scrubbing through the same 3 hour sports video for both tests.

Bob

Bob,

Thanks for the update… it sounds like you ran your tests with scrubbing in the apps themselves? How about the scrubbing via AirPlay, which is a slightly different experience? What I’m most interested in doing is starting the AirPlay and then putting down the device, then using the Apple TV remote to scrub directly on the TV.

Thanks,
-Josh

I wanted to add that my favorite implementation of video scrubbing is what is done on Air Video HD where the main screen stops where you start the scrub and a smaller screen shows you video as you scrub through the video until such time as you lift your finger then the main screen starts at the new location. I am currently pulling my videos off of Table with a Python script called Tablo2go and moving them to a NAS where I access them using Air Video HD to stream wherever they are needed.

Bob

I will run a test for you Josh.
Bob

Josh,

OK, with the iPhone you can only use mirrored Air Play so there is no interaction with the Apple TV remote. With the iPad app you have Air Play available from the app but when you use the remote to scrub it turns the screen black while scrubbing.

With Air Video HD you can see the screen fast forwarding as you use the remote.

Bob

Alas, that is sad news. The “blind fast forward” is one of the things my family dislikes most about the cord cutting experience. Maybe @TabloTV can look at fixing this for future? It doesn’t look like generating IFRAME playlists onboard should be a big issue.

Here’s a thought… what format does your Python script export the videos in? It there’s a back-end API that provides access to an MP4 stream, I might be able to hook a custom app up to that and get a better experience.

The python script pulls the raw .ts files stored in Tablo and glues them into a mp4 using FFMPEG

Okay… so a little more digging done, and here’s the skinny. Given that the Tablo hardware is already transcoding the video on-board the box, generating an IFRAMES playlist should be trivial. Here’s the documentation on how PBS did it, and a python script that will generate an updated master playlist which includes IFRAMES to allow Apple’s “trick play” (proper scrubbing) to work:

http://open.pbs.org/blogs/open-pbs/how-pbs-is-enabling-apples-trick-play-mode/

I’d really love to hear from @TabloTV about whether they could get this into a firmware update and what kind of timeline might be involved. It would be a game changer for those of us AppleTV and AirPlay users, and would probably be something they’d need to look at for the (rumored) new Apple TV App Store.

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I’ve got a back-end Apple server hosting a web server and my iTunes share. I’ll bet I could update the PBS scripts to generate updated playlists hosted on my server and use those and a custom native app to get the job done… hrm… because I didn’t have enough side projects already…

Here is the link to the Python script tablo2go.py https://sites.google.com/a/moboard.com/tablo/home

I am holding off all Video projects until next month where I am hoping to see what direction Apple is going with on Apple TV.

I will not hold my breath though.

Nice meeting you,
Bob

Bob,

Likewise. After next month’s Apple announcement and some feedback from Tablo, I’ll see where this is going. I haven’t even gotten my Tablo yet, and I’m already liking it better than Simple.TV. The community alone appears to be worth the change in platform.

If Apple does announce an app store for Apple TV we would LOVE to have a native app for it which would eliminate the need for AirPlay.

The main problem with AirPlay is that the app doesn’t have a lot of control over the video once it’s released into AirPlay mode.

@TabloTV,

It’s not just eliminating AirPlay that’s the issue. Your HLS encoding engine has to support generating IFRAME only playlists to support “trick play mode”. This requires inspection of each HLS segment to identify the byte offset where particular image frames are, and including that information as part of the HLS manifest. If you did that with your current software, then Apple “trick play” (visual scrubbing) would work with the current software.

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@thanatos0801 - Our engineers took a look at this quickly this morning. It should be doable in theory but there may be a few unknown pitfalls. We’ll be taking a closer look at this in the fall.

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@TabloTV - GREAT to hear it! I have a full time job, but I’d be happy to help with iOS or encoding features in my spare time. I’d be happy to sign an NDA or whatever you’d like.

As a side note in case other people like me are searching through the forums, the latest version of the iPhone app DOES NOT require Airplay mirror mode. I just setup my Tablo and linked the video playback to my Apple TV directly, minus mirroring, and I do have Apple TV remote functions. So that part is great.

Now if we can get those IFRAME manifests, my Apple-centric TV experience will be perfect.

I went back and retested my iPhone 6+ and you are correct on it working with Apple TV without needing to use the Mirror Mode. Apparently when I tested it for you yesterday I did not wait long enough to see if it connected before I selected mirror mode. It did kind of throw me off track when I had to select Apple TV from outside the app instead of inside the app like on the Tablo iPad app. They really need to take the time to code this app as a iOS Universal app. In the long run it will save coding time and will ensure that the look and feel will be the same across iOS devices. Also the versions will not get out of sync between the two devices as they are now.