Mar 31, 2007
Mar 30, 2007
Apple - QuickTime - Technologies - MPEG-4
Apple - QuickTime - Technologies - MPEG-4
Still trying to sort out the different encoding settings to get my content over to the Apple TV. The baseline Quicktime export to Apple TV settings kind of suck IMHO, and they're not broken out/documented anywhere so you can tweak and or set them up on your own
Export To AppleTV specs - MacNN Forums
Export To AppleTV specs - MacNN Forums
Ok, I just tried the "Export to AppleTV" command in QuickTime Pro 7.1.5 and here are the specs of the resulting file:
.m4v extension
H.264 video codec, 640 x 480 (that was my source file), 24fps ( my source was 24fps)
AAC audio codec, 44.1kHz stereo
Overall file bitrate is 2.2Mbps
So we're at the low low end of DVD quality on the bit rate. I had no option to adjust any settings, so I have to wonder if MPEGStreamclip or Handbrake may offer an update soon to allow us to tinker with settings when we convert files.
Overall, good effort by Apple on the preset, but it would be nice to adjust the settings to get more bits for video, and par the audio down to something like 32kHz AAC at 96 or 128kbps.
I haven't tried HD video yet, I will tomorrow to see what it spits out.
Ok, I ran an HD test this morning on the Export to AppleTV command in QuickTime Pro.
My source file was a 19 second DVCPRO HD file, 720p, 23.98fps. DVCPRO HD stores files at a resolution of 960x720, and when you play them back, QuickTime Player shapes it at 1248x702 to get the aspect ratio correct.
I ran the exporter, and what I got was a .m4v file. Video was using H.264, at a size of 1248x702, at 23.98fps. Data rate on the video track is 4.85Mbps. Audio was AAC, 44kHz stereo, at 128kbps. That puts the whole file at 4.9Mbps, just under the maximum AppleTV spec data rate of 5Mbps (according to the Apple website)
So it appears that the basic QuickTime exporter does a great job of maximizing available data bandwidth for HD content, when it is given a high quality source such as DVCPRO HD. The resulting video was a bit soft, but most of the detail was there, and I think it would look good on an HD set through the AppleTV.
To update you on the SD test that I did, the video data rate is 2.15Mbps, and the audio was at 128kbps. Not bad, but just at the bottom end of DVD quality. It would be better if the exporter would give standard definition video a higher datarate, such as at least 3.5Mbps, so we could get DVD quality bitrates out of it.
HD results are promising. I'm fairly impressed there.
Let's hope that third parties tie into this exporter, and allow us to up the datarate on video so we can get some better results out of standard definition content.
Overall, I'm fairly impressed.
I was using a G4 MacMini for the exports. I would definitely get an Intel Mini or iMac for all exports. You will have much better export times.
Mar 29, 2007
Mar 28, 2007
Mar 27, 2007
Mar 26, 2007
Apple TVUpdate:
I got around to dumping some video, photos and screeshots of my latest toy. This definitely 'sucks less' than the Aiport Express! (old iTunes streaming solution that didnt work well)
I'm running a wrt54gl linksys router "g" and network speed for streaming is not an issue.
Initially, hooked the box up with no net connectivity as a freak March thunderstorm took out the VDSL router. It must do a lot of talking back and forth to the iTunes Music Store (iTMS) as there were lots of initial delays, and network waits, only to come back reporting the obvious.
At $100 these would sell like crazy.. at $299 it might be a bit steep for what it does. The biggest disappointment is the size of the internal drive. 40Gb is not much, heck an iPod is larger these days! Also, the remote could really use a scroll wheel. Getting through a long playlist is painful, the clicker will wear out in short order I'm thinking! No power switch either, to shut down you have to yank the cord. WTF? seems a bit atypical for an Apple design. Guess you're never supposed to turn it off!?
There is also some confusion about 'syncing' versus 'streaming'. For folks with a really large collection of music in iTunes, you want to stream the music, and only sync photos/video.
There also is no way to override the default prefs. of syncing priority. Movies, TV Shows, Music, Podcasts, Photos. In that order only, so if you fill up the HD you'll get only a portion of, or none of your Photos sent over. Not sure why they did not implement the iPhotos 'photocast' capability into the device.
Apple TV & iTunes - Flickr photoset
Unit runs really hot, so you need adequate space around it.
The HDMI connection, (cable not included) worked perfectly when paired to a 37" SCEPTRE LCD HDTV (the one from Costco last winter? 2005/2006)
iPhoto content/slideshows look stunning, early iTMS video downloads show pixelation. .mp4 rips from DVD using handbrake are okay, although you may want to step up to 2 pass H.264 encoding for files that you want to keep around a while!
One video (an .mp4 file) did lock it up.. ironically enough, it was Steve Jobs stanford commencment address from a few years back. Completely locked the unit up.. had to pull the power cord to reset.. DOH! :-)
Overall though, once the internet connection to the outside world was restored, the thing works prettly flawlessly, and is a great way to get the content from the upstairs office computer (a dual G5 2.7Ghz PPC PowerMac) to the famliy room downstairs!
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