-
Ideal rendering options for Motorola Xoom?
Has anyone come up with the best rendering settings for a video for the Motorola Xoom for 720p video? I.e. best balance between quality video, smooth playback, and smallest file size?
-
18 Replies
-
I would start with Sony AVC Internet 720-30p template and adjust the bit rate for the file size you desire. Start with 3.5Mps (which should be very good quality) and work your way down from there. Every 1Mbps in bit-rate is approximately an additional 8MB in file size per minute of video.
~jr
http://www.johnrofrano.com
http://www.vasst.com -
The Xoom should take videos up to 1920×1080/30p, but don’t use High Profile. John’s recommended Internet Profile is probably a good starting point… you don’t need anything beyond 720p for the tablet itself (maybe if you’re sending HDMI to an external screen).
I received a different tablet, based on the same Tegra 2 SOC, on Friday… have not had a chance to tweak video for it yet. But probably soon.
-Dave
-
Anything higher than 3Mbps on my Xoom will stutter and occasionally freeze when playing out over HDMI or internal view.
I’m with John. Higher bitrate 720p is more reliable (thus far) for me than lower bitrate 1080Douglas Spotted Eagle
VASSTCertified Sony Vegas Trainer
Aerial Camera/Instructor -
Not denying it… particularly if you’re viewing on the device. Apple so far only supports 720p, and I think they limit it to base profile, even on the iPad 2. Then again, those of us wise enough to go for Android at this point must demand more!
Probably not a consideration at 3Mb/s or so, but the speed of the flash may also be an issue. I guess the Xoom has a big chunk of NAND flash internally… any idea how fast it is?
Just for yucks, I tried a YouTube video from a few years back. This is 720/30p AVC, encoded at 6146kb/s (including 128kb/s AAC audio), something derived from the original “Internet” AVC profiles, I’m sure. Dropped this onto a plain old USB stick, put it in my “Adam” tablet… plays perectly well, not a hint of a skip or jitter. Same video, in 720/30p 6Mb/s WMV also played just as well.
I tried a 720/60p video I had lying around, also about 6Mb/s. It played with a tiny bit of jitter… and in slow motion. Tried a higher bitrate MPEG-2 HD file.. not dice. No surprise, either, mobile devices are really looking for MP4/AVC.
Now this is on Android 2.2, not 3.0. I got much the same results with three different video players (stock Android, ES File browser player, and a customized player that’s part of the table software bundle.. not sure what the difference is).
-Dave
-
I played a bit more with video on the Adam.
I found that, using Sony’s AVC encoder, I get perfect video at 720/24p@4Mb/s, on either baseline, main, or high profile. When I bump this up to 6Mb/s, I start having issues. And going to 1080/24p at 4Mb/s, same issues.
The issue here is de-sync, and it’s pretty clear what happens. The player isn’t quite keeping up with video decoding. But it doesn’t really do anything about that. So audio slowly walks away from video, and you wind up at the end with just the video playing. The proper action is to drop frames to keep up with the video, but none of the Android players I’ve tried will do this. This was kind of a 1980’s innovation, if not earlier, so I’m actually kind of shocked it’s not being done here.
But I had seen both WMV9 and MPEG-4/AVC play just dandy before at 6Mb/s, so I did a few more experiments. Seems that Main Concept, 720/24p, main profile, VBR, average 6Mb/s, peak 8Mb/s, plays just dandy on the Adam, no lost frames. We don’t have the controls over GOP we did with MPEG-2, so I really don’t have a good explanation of the difference here, but there it is. This also helps explain why some folks online have had more trouble with x264 encoded samples: the Tegra encoder must be sensitive in ways not yet fully qualified.
I tried 1080/24p at 4Mb/s from Sony and the same 6/8Mb/s with MainConcept. Neither plays without lag.
-Dave
-
Hi guys,
Are these suggestions still current?
If so can someone tell me how to adjust for these settings?
In the dropdown for Sony AVC (in V10)I’m not seeing a template for 720-30P and if I select the 1280×720 template the frame size is greyed out.
Thanks in advance for your help,
Randy -
[Randy Brown] “Are these suggestions still current?”
Yes.
[Randy Brown] “If so can someone tell me how to adjust for these settings? In the dropdown for Sony AVC (in V10)I’m not seeing a template for 720-30P”
Are you saying the you don’t see Internet 1280×720-30p listed as a template? You should it’s one of the default templates supplied by Sony.
[Randy Brown] “… and if I select the 1280×720 template the frame size is greyed out.”
It should be greyed out because 1280×720 can only be 1280 wide by 720 high. There is no need to change it.
~jr
http://www.johnrofrano.com
http://www.vasst.com -
Excuse my ignorance JR but is 1280×720 the same as 720p?
If so do I just change the default bit rate of 8,000,000 to 3,000,000?
Also, the footage is from XH-A1 set at their “progressive” 30 fps setting, should I leave the frame rate at 29.97?
Thanks very much,
Randy -
[Randy Brown] “Excuse my ignorance JR but is 1280×720 the same as 720p?”
No need to apologize. Yes, 720p and 1280×720 are the same thing. People are always looking for shortcuts for naming things so 720p means 1280×720 progressive and 1080i means 1920×1080 interlaced.
[Randy Brown] “If so do I just change the default bit rate of 8,000,000 to 3,000,000?”
Yes, just change the bit-rate to whatever you want.
[Randy Brown] “Also, the footage is from XH-A1 set at their “progressive” 30 fps setting, should I leave the frame rate at 29.97?”
Yes, this is another renaming that people do. 30p usually means 29.97fps progressive and 60i means 29.97fps interlaced (which is 59.94 interlaced fields). Confusing… i know. 😉
~jr
http://www.johnrofrano.com
http://www.vasst.com -
Thanks so much JR…just one more question; the default bit rate of 8,000,000 means 8mbps right?
You guys in that old thread were talking about 3mbps so I rendered out to 3,000,000 and it looked pretty bad (lots of blocking).
I’m having to send this guy clips to test over the internet so anything you can tell me could really help us out.
Thanks again so much,
Randy
Reply to this Discussion! Login or Sign Up