[mythtv] Possible playback scenarios for the iPhone

Chase Douglas chasedouglas.lists at gmail.com
Mon Jul 21 16:06:37 UTC 2008

On Jul 21, 2008, at 11:56 AM, Kevin Kuphal wrote:

> On Sun, Jul 20, 2008 at 2:13 PM, Chase Douglas <chasedouglas.lists at gmail.com 
> > wrote:
> On Jul 19, 2008, at 5:19 PM, Kevin Kuphal wrote:
>> On Fri, Jul 18, 2008 at 5:58 PM, Chase Douglas <chasedouglas.lists at gmail.com 
>> > wrote:
>> I am interested in developing a frontend for the iPhone with live tv
>> playback, but there are two hurdles along the way:
>> 1. Content is encoded in the format coming from the tuner device, and
>> as far as I am aware, no tuning device outputs an iPhone compatible
>> format
>> 2. The iPhone SDK (I'm trying to keep this under Apple's terms as
>> well) has no streaming video support. At best, it can take a static
>> file and stream that from a URL, but there's no support for streaming
>> mutable content like an rtsp:// stream. A further complication is
>> Apple's insistence that developers cannot access the framebuffer.
>> The first issue could be remedied through live transcoding before
>> streaming to the device. This isn't implemented yet, but is possible.
>> The second issue is a much higher hurdle. Without the ability to play
>> streaming content within the SDK, the only way this could work is
>> through software decoding and playback through either a quartz
>> graphics layer or an opengl layer. I've never written any rendering
>> software but I know it's possible. My question is: would the iPhone  
>> be
>> powerful enough for a reasonably encoded stream to be played back? By
>> reasonable, I'm thinking standard mpeg-2 or the mpeg-4 encoding, but
>> keeping in mind that I'll have no access to the hardware acceleration
>> already present on the iPhone.
>> Have you seen this?
>> http://code.google.com/p/mythtv-for-iphone/
>> Kevin
> That will only work with streaming static, recorded content. A live- 
> streaming implementation is needed to be able to watch live tv  
> playback.
> "Live" streaming is only streaming a recording in progress.  It  
> shouldn't be that hard to browse the guide, kick off a recording,  
> and then streaming that.

That's certainly a possibility, but it has some flaws. First, it will  
kick you out when the show is over, but the user may want to continue  
watching. This is even worse when you are watching a sports even which  
goes longer than the scheduled time frame. Channel changing would also  
be non-existent without starting the whole process over again,  
including the steps to cancel the original recording for the live tv  
you don't want to view anymore. Also, this still doesn't get around  
the issue of the iPhone OS wanting a static file it can read from at  
any point at any given time. It won't like not being able to read the  
end of the video file when you first start playback.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mythtv.org/pipermail/mythtv-dev/attachments/20080721/1bc83451/attachment.htm 

More information about the mythtv-dev mailing list