View Full Version : HD video playback
According to the specifications mentioned on the main page, the HD resolution (1280x720) will be only possible with MPEG-1. It makes sense, because MPEG-1 is the least demanding format. For other formats the CPU probably won't be able to decode them realtime.
Could someone confirm this? I think many people here are expecting the device will be able to handle h.264 1280x720 video. I'm afraid it won't.
Actually I think that the specs mentions 720p support for all the video codecs along with mpeg1, as hd video is more likely to be used with codecs like wmv, mpeg2 or h.264 rather than mpeg1, for instance where on the net or on which media could you find 720p mpeg1 ?
Fo HD video the used formats (not codecs, codec is a SW) are VC-1, MPEG-2 and MPEG-4 AVC (H.264). The last one is used in 99% of movies I've seen. But imagine how much processing power you need for this format. In my A64 3500+ MPEG-4 AVC 720p decoding eats 50-80%.
MPEG-1 is the least demanding format for decoding. So it makes sense that only in MPEG-1 the HD playback will be supported. And from the published specs it looks so.
I guess we'll have to wait for someone to actually test it.
Yup my mistake about confusing codecs with formats and wmv with VC1.
Another thing I'm wondering :
A2 hard disk is in FAT32, but will A3 use this File System too? This would prevent us from storing 720p hd movies having a size of more than 4GB, especially those encoded in MPEG1, as this format being the oldest, it has the lowest file size/movie quality ratio.
I hope that the windows logo on the back of the A3 would allow it to use NTFS to remove the file size limit...
I hope there will be a Linux logo and Ext3 filesystem. ;-)
I think we already have answers to most of our questions with the product details at the end of the english manual, section applications:
http://www.cowon-germany.com/A3/A3_EN_manual_1%200E.pdf
As the note 1 says 720p isn't supported with all the the formats it accepts, then it is unlikely to support h.264 as you were thinking...
the FS is still FAT32, so if you wanna play hd movies having a size of more than 4GB, you'll have to split it...
After those disappointements now I have to wait for accurate reviews of A3 on its 720p compatibility, to make me believe again that upgrading my A2 is really worth it...
I don't think the A3 will use FAT32 (at least on the 60GB version) because it would not allow you to use all of the hard drive.
The X5 60 gigs is FAT32 and AFAIK works fine. You just need to get a little unconventional if you want to reformat it.
and my 400gb HDD is also in FAT32 :D
and my 400gb HDD is also in FAT32 :D
Good gravy! Multiple-boot need?
- wader
siilverrr
12-08-2007, 16:20
According to the specifications mentioned on the main page, the HD resolution (1280x720) will be only possible with MPEG-1. It makes sense, because MPEG-1 is the least demanding format. For other formats the CPU probably won't be able to decode them realtime.
Could someone confirm this? I think many people here are expecting the device will be able to handle h.264 1280x720 video. I'm afraid it won't.
I received my A3 today, and have tested it with a couple of 1280x720 files (episodes of "One Piece", in case anyone is interested [biggrin]).
Forgive my lack of technical knowledge.
Using the information against the file from within the player's own browser, the first example is as follows: 1280x720, H.264, 23.98fps, 1374kbps, MP3 48khz, 192kbps, Stereo, .avi container.
I confirmed this is H.264 using VLC media player.
Result? Plays, but the video is choppy and has visible artifacts. It does not appear to go out of sync with the sound (which, incidentally, is flawless), but this is not something you'd want to watch over and over.
The second 1280x720 example uses the avc1 codec for video (the A3 recognises it as H.264 again, but there must be a subtle distinction I've failed to grasp in my ignorance). The file extension is .mp4. On this occasion there is no picture at first, and then a lot of garbled information as the player attempts to decode a codec it clearly isn't happy with. The AAC audio stream plays effortlessly all the while.
Perhaps someone who fully appreciates the intricacies of the H.264 format won't be surprised by these results, and I hope this information is useful.
FYI, I am using firmware 1.14A. I also tested these files with 1.11A, which came preloaded with the device, and the results were the same.
The A3 is indeed FAT32 and Windows states it has 55.8GB free space to start with (60GB version).
hmmm siilverrr thats disappointing, did you can a chance to test it with an mpeg1 hd file ?
Here is a Sample
http://www.digigami.com/megapeg/samples/Least_Likely_PSA.mpg
siilverrr
12-09-2007, 01:41
hmmm siilverrr thats disappointing, did you can a chance to test it with an mpeg1 hd file ?
Here is a Sample
http://www.digigami.com/megapeg/samples/Least_Likely_PSA.mpg
Plays more smoothly than my test samples above, but it's far from perfect.
Some noticeable slowdown, esp. in the scene where they are all roundhouse kicking each other. At least there are no artifacts.
Lip-syncing is a definite issue throughout, caused by the video being ever so slightly behind the audio from practically the offset. Oddly, it catches up for one scene (When Maggie Q says "Eighteen to Twenty-Five").
The AV Out only appears to go up to 480p (when set to Component (p) - confirming austinv's comment in his review thread), however, so hopefully this isn't too disappointing. (Setup>Display>Av Out>Composite/S-Video/Component (i)/Component (p).)
These are the results I was expecting. I was afraid that a mobile chip can't decode a h.264 HD video. Maybe in 1 or 2 years. Let's wait for Cowon A4. :-)
Btw. MPEG-4 AVC is equal to H.264. Different names, same format. Just like FireWire, IEEE 1394, DV Link, i.Link etc. So it is no mystery that the player recognizes both videos as H.264.
I believe the specific CPU used in the A3 is the TMS320DM6441.
TMS320DM6441 Product Homepage
http://focus.ti.com/docs/prod/folders/print/tms320dm6441.html
TMS320DM6441 Product Bulletin (Overview)
http://focus.ti.com/lit/ml/sprt402/sprt402.pdf
DaVinci for PMPs
http://focus.ti.com/lit/ml/sprt394/sprt394.pdf
Video Benchmarks
http://focus.ti.com/lit/ml/sprt379a/sprt379a.pdf
That last one may give us some idea of DaVinci's playback capability, but note that it only references TMS320DM6443 and TMS320DM6446 which are higher-end parts. For both, h.264 playback is limited to D1 resolution (720x480). They both support 720p playback using VC1/WMV9, MPEG-4 SP, or MPEG-2 MP.
TMS320DM6441 - 4104 million instructions per second (MIPS) at a clock rate of 513 MHz
TMS320DM6443/TMS320DM6446 - 4752 million instructions per second (MIPS) at a clock rate of 594 MHz
These are the results I was expecting. I was afraid that a mobile chip can't decode a h.264 HD video. Maybe in 1 or 2 years. Let's wait for Cowon A4. :-)
Btw. MPEG-4 AVC is equal to H.264. Different names, same format. Just like FireWire, IEEE 1394, DV Link, i.Link etc. So it is no mystery that the player recognizes both videos as H.264.
I don't know about the one used in the A3, but the latest version of DaVinci can, the TMS320DM6467, according to Ti: "...multi-format HD encode, decode and transcoding up to H.264 HP@L4 (1080p 30fps, 1080i 60fps, 720p 60fps). For more information see www.ti.com/dm6467pr." And it's rated at the same core voltage as the TMS320DM6441.
hopefully firmware updates will fix these problems. does it support mkv in 720p ?
I've a bunch of 720p MKV episodes of Heroes, Dexter and Pushing Daisies. Both Heroes and Pushing Daisies seem to be encoded with H.264 HP and so don't play. However Dexter was encoded with H.264 MP so did play but was unwatchably jerky. Hopefully that'll be fixed in new firmware... or maybe it's just too much for the little gizmo to cope with. I wouldn't be suprised as those files do require a lot of processing power, even my desktop PC struggles sometimes :P
rcr0412, Wootz
You didn't read the previous posts? The A3 will NEVER be able to play H.264 720p videos. It's processor just isn't powerful enough to make it work. Even with a bilion of firmware upgrades.
rcr0412
MKV is just a container, it doesn't say anything about video compression. But the video compression is very likely to be H.264, so it won't play.
austinv
Do you know about any device which uses the new TI DaVinci TMS320DM6467? It would be really great to have these video playback capabilities in a portable player.
Btw. if I woud like to have a PMP/PDA combination (something like Q5) with H.264 HD playback, I'm afraid such device would need 2 CPUs - one for PDA and the other one for PMP functionality. Am I right?
that's too bad. However I can't imagine anyone would need to look at hi-def video on the go. If you really need hi-def then get a 46 - 60 inch TV at home. You would really get the full feeling of hi-def there. on a 4inch screen....I am not sure what kind of experience one can expect. Anyway.....cheers.[laugh]
Starchild
12-11-2007, 06:58
Is there any reason I should use 720P HD movies instead of "normal" movies if I'm planning to watch them on the A3 itself and not on an HD TV?
Is there any reason I should use 720P HD movies instead of "normal" movies if I'm planning to watch them on the A3 itself and not on an HD TV?
Absolutely not. The screen size of A3 is 800x480, so you'll get best picture if you can fit this resolution (be aware it's above NTSC resolution). But hopefully with MPEG-4 ASP compression the player can play 800x480 videos.
that's too bad. However I can't imagine anyone would need to look at hi-def video on the go. If you really need hi-def then get a 46 - 60 inch TV at home. You would really get the full feeling of hi-def there. on a 4inch screen....I am not sure what kind of experience one can expect. Anyway.....cheers.[laugh]
It's not so much that we need to view HD video on the A3 itself, but for those of use that collect video at HD resolutions, it would be nice to be able to use the same files at home and on the go - without having to do any video conversion for use on a portable player.
It's not so much that we need to view HD video on the A3 itself, but for those of use that collect video at HD resolutions, it would be nice to be able to use the same files at home and on the go - without having to do any video conversion for use on a portable player.
Im going to have to keep two files for every movie, H264 High profile is going to be used on my pop corn hour/tvix machine.
Also I do plan to use A3 as a video player connected to a TV. And the A3 supports HD TV-OUT.
Search for threads on this site showing the poor performance of HD (Component out) from the A3.
ZetastreaM
12-19-2007, 21:11
that's too bad. However I can't imagine anyone would need to look at hi-def video on the go. If you really need hi-def then get a 46 - 60 inch TV at home. You would really get the full feeling of hi-def there. on a 4inch screen....I am not sure what kind of experience one can expect. Anyway.....cheers.[laugh]
Heh, I was gonna mention the same thing. HD on a 4" screen seems only for bragging rights only...well..unless you want to output that to a larger screen that is.
Heh, I was gonna mention the same thing. HD on a 4" screen seems only for bragging rights only...well..unless you want to output that to a larger screen that is.
no point at 4" since the video has to be scaled down anyway.
Heh, I was gonna mention the same thing. HD on a 4" screen seems only for bragging rights only...well..unless you want to output that to a larger screen that is.
Nail on head [yes]
is the component out locked at 480p for the moment ?
is the component out locked at 480p for the moment ?
yes it is
vBulletin® v3.7.2, Copyright ©2000-2009, Jelsoft Enterprises Ltd.