mp4 video playback capabilities?
 

Nokia's website shows that the n810 has h.264 and mp4 video playback capabilities. Is the n810 fast enough watching videos (say, transcoded from tivo to an ipod friendly format, for example)? Or is it choppy?

I am torn between a few different devices, but keep coming back to the n810.

Thanks,

-jamie

Re: mp4 video playback capabilities?
 

I was watching 320 x 240 15fps streaming video over my EVDO verizon cellular link ..It was a bit hiccup like but most of the time it just streamed fine. I even had other programs like the web browers open and xchat
CJ

Re: mp4 video playback capabilities?
 

Oh Yeah Mpeg4 i believe.

Re: mp4 video playback capabilities?
 

Note that I am asking about the playback aspect, from a show stored on a microSD card, not just streaming.

Re: mp4 video playback capabilities?
 

I'm trying to watch some Google Techtalks in mp4 from Google Video (downloads for Video IPod/Sony PSP) on N800 with OS2008 Beta with default Media Player. It kinda works, but audio/video comes out of sync and video becomes choppy after a short time, and some of these videos fail to start playing from the beginning - you need to move time slider to skip first few minutes. Overall, pretty disappointing. Maybe OS2008 and/or MPlayer will do a better job.

Re: mp4 video playback capabilities?
 

^ what's the resolution and compression for those clips?

Re: mp4 video playback capabilities?
 

Mine are encoded at 320x176, or 320x240 for tv shows (basically using ipod settings), usually < 900k

(839.88 kbits/s)

I have a couple of movies which seem to be mostly around here:
Apple MPEG4 Decompressor, 640 x 272, Millions
AAC, Stereo (L R), 48.000 kHz
1012.50 kbits/s

Which, on the ipod, plays fine.

Thanks...

Re: mp4 video playback capabilities?
 

If MPEG4 is choking, I can just imagine what an h.264 encode will do. As someone who does encoding for a living, I don't mind converting video files to a formate that the 810 likes. Has anyone been able to get any video file to play with a resolution of 640X480 at 29.97 fps with smooth playback? What flavor of video does the 810 like the most?

Yes I know most of you on here don't really care about video as you have bigger fish to fry with this device. I just still can't help trying to justify my purchase of an 810. :)

Re: mp4 video playback capabilities?
 

Well, yes, video on the n800 is quite disappointing (considering that on a psp I can play with no issues h264 encoded videos at 480x272).

Re: mp4 video playback capabilities?
 

jamiepda: This has been covered a couple times before on this forum, which is why you aren't seeing many people chime in. I'll try and answer this in hopes that people searching in the future find this post.
Executive summary: The bandwidth between the CPU and LCD controller on the N800 is the absolute limiting factor of what's theoretically possible. IIRC, 640x480@24fps would be close to the theoretical limit of that bandwidth. (See here for more info.) the N810 is almost exactly the same hardware, with the only real internal changes being some more flash memory, miniSD vs 2x SD, and a GPS, so it shares the same limitation.
Now onto, the good news: The LCD controller can do pixel "doubling" with no performance impact (arbitrary scaling, really). If you're going to transcode anyways, xvid/divx video with mp3 audio works great. 400x240 @ 800Kb/s or so is bulletproof. It looks great on the screen and plays flawlessly even with lots of fast motion. The builtin media player is decent and mplayer is available as well thanks to the excellent work of a forum member named Serge. Mplayer supports a couple of formats the builtin player doesn't and vice versa. AFAICT, one of the big things that might affect playback is actually the audio encoding. MP3 decoding usually happens on the DSP on the N800. Even if it's done in user space there are more than one fixed-point, ARM optimized mp3 codecs available. The situation for other codecs varies but I could definitely see AAC decoding taking siginificantly more CPU power. Anyways, that's someplace to start at least. Hopefully I don't have anything too horribly wrong in there. I'm sure someone will correct me if I do.

-John

Re: mp4 video playback capabilities?
 

Many thanks for the detailed information!

Re: mp4 video playback capabilities?
 

Most encouraging news I've heard all day.

Re: mp4 video playback capabilities?
 

I'm particularly interested in how the n810 plays with Tivo2go. Anyone using this setup? I haven't purchased a Tivo, but I'm strongly considering the new HD box and being able to play the Tivo2go recordings on the 810 without additional transcoding.

Re: mp4 video playback capabilities?
 

How about H.264 instead of xvid? With everything else being equal (400x240, 800Kb/s, MP3 audio etc) could one still expect good results? In that situation it would just be a bump in CPU usage and not video bandwidth per se. Or would I not likely notice the difference between the two encodes?

I know I could just try it myself, but I'm hoping to start transcoding in advance of my N810 delivery sometime at the end of the month. I have a few hundred movies and TV episodes in full-res xvid and I thought I would get my mythtv box to slowly chew through them all. But I don't want to start that and find out the resulting files are sub-optimal.

I've searched the forum for a "definitive" answer to H.264 playback but can't seem to find one. I do realize that Nokia's manual states support for H.264 at "320x240" but others have suggested larger sizes will work.

Re: mp4 video playback capabilities?
 

I'd like to hear experiences with H.264 as well, both in the built in player or mplayer.

H.264 is supposed to give smaller file sizes with the same visual quality, right? :)

Has anyone done extensive testing?

Re: mp4 video playback capabilities?
 

Hello, what are you using to transcode? I've tried Dr. Divx (original) and Divx Converter, neither worked. Thanks!

Re: mp4 video playback capabilities?
 

I have no idea about h.264 . If i get a chance, maybe I'll try encodimg something in that format and see how it plays.

I run linux on my desktop so i use a command-line program called tablet-encode to encode things. i also use mediaserv to do on-the-fly converting for when i'm at home watching videos over wireless. apparently nokia released something called media converter for windows that has a nice gui, but i've never tried it.

anyways, what problem are you having with dr. divx?

Re: mp4 video playback capabilities?
 

Thanks, both to jamiepda for the question and Johnx for the thorough answer.
I'm trying to get some tivo to my device, but the 'cleaned' mp4 is about 1Gb for a 30 min show. I saw a how to convert to ipod, but wasn't sure if I wanted the .5 scaling they suggested. The file doesn't list any details so I don't know the encoding or resoluton even. I'll let you know when I get something that works.

Re: mp4 video playback capabilities?
 

Prevent this from happening again: Take this information and put it in the Wiki for all to see.


}:^j~
YARR!

Capt'n Corrupt

Re: mp4 video playback capabilities?
 

Except that it doesn't work. Divx isn't a supported format. See the manual page 39.
I'm sure that JohnX's setup works for him, but not with the standard player.

p.s. found an encoder that works; https://garage.maemo.org/frs/?group_id=26
the only option there is bitrate. The rest of his information may still be useful to more advanced users.

Re: mp4 video playback capabilities?
 

As has been said, this has been covered many times.

The popular meaning of "DivX" is supported, with pretty much all the converters targetting what could be considered DivX files (although only certain FOURCCs are recognised), apart from Nokia's Internet Tablet Video Converter which targets MP4/AAC.

There are also many converters, such as Nokia's ITVC, my own tablet-encode and Urho's MediaConverter (which you linked to).

Re: mp4 video playback capabilities?
 

tablet-encode tells mencoder to use the lavc codec "mpeg4." In the mencoder man page the description next to that codec is: "MPEG-4 (DivX 4/5)"

I'll leave others to debate what "DivX" really means but I will say that video encoded in such a way works great in the built-in media player.

-John

Re: mp4 video playback capabilities?
 

Firstly i'd like to thank everyone on this thread for helping a total novice when it comes to the n810. i got mine yesterday and couldn't understand why it didn't play standard mp4 files. now I know and i'm using media converter osx and it works great.
another question though. i'm using etymotic headphones and the max volume is just about ok but i'd really like a bit more vol if possible. so, can anyone recommend a set of low impedance in ear headphones (i'm assuming lower impedance = higher volume???) or any other work around?
thanks

Re: mp4 video playback capabilities?
 

I own a Tivo

A Nokia N800 with 08 flash

Tivo Desktop 2.5 w/ 24.95 plus upgrade.

I downloaded a show through desktop, converted it with the mp4 compatible profile. Plugged in N800 via usb and trasnfered file. Now it is playing very nicely no video skipping with audio insynch. No problems seeing it with default media player.

Now the next time I need to distract my son I can hand him a 30 min episode of Power Rangers: Operation Overdrive "Behind the scenes" episode.

So if you own a Tivo and are willing to use all "the mans" software restrictions and fees it works well!

Re: mp4 video playback capabilities?
 

Thanks for the info and the size information I got from another thread.

Ultimately - after a few trials and errors this is what worked for me using just mencoder.

> mencoder input_movie.avi -ovc lavc -lavcopts vcodec=mpeg4 -oac mp3lame -vf scale=400:240 -o output_movie.mpeg

The movie now plays full screen on the N810 with sound matching correctly. I left out the bitrates - leaving it to the same as the source file though.

Re: mp4 video playback capabilities?
 

Mike,

I've not got completely to the bottom of this yet, but I've been trying out SUPER for video encoding for the N810. The only thing I've found to be consistent regardless of other settings is that if I use MEncoder, the volume is really really low, if I use ffmpeg, the volume is perfect (by that I mean in balance with audio, system sounds etc). I suspect there is a subtle problem with the transcoding that's being done and the volume level is being lost/decreased.

Anyone with more technical knowledge of this area able to suggest something?

Mark

Re: mp4 video playback capabilities?
 

Can you try with the official Nokia Video Converter application and tell us how it compares audio level/quality wise to the other apps you tried?

Official Nokia Internet Tablet Video Converter: http://www.nokia.com/betalabs/videoconverter

Re: mp4 video playback capabilities?
 

I just figured this out this week. The media player has separate volume from the main volume. Once media player is running, the zoom rockers control the media player volume, you need to change the master volume with the onscreen icon. It might not be your headphones.

Re: mp4 video playback capabilities?
 

Tivo to Go works great - converting to mp4 automatically via Tivo desktop, videos are great. No need to run them through Nokia's video converter.

Re: mp4 video playback capabilities?
 

I was wondering, since the limitation of video playback on the N8x0 is the LCD bandwidth, couldn't we get a player like mplayer to play a non-transcoded video by scaling down the uncompressed frames to 400x??? before sending to the LCD? That way, we could watch divx videos off the wifi network without having to transcode them :)

Re: mp4 video playback capabilities?
 

No, LCD bandwidth is not a limitation for low to medium resolution videos. There is no need to downscale them that much. In the worst case, if you hit LCD bandwidth limitation, you will just see tearing and have a noticeable amount of frames dropped, but nothing too critical that would make video completely unwatchable (for example, even dropping framerate to 15fps, video may remain watchable). But if CPU is the bottleneck, video playback will completely stall or regress to showing frames just occasionally, making watching video impossible.