Playing 320x240 video on a VGA PPC ?

[timmer]

Considering the VGA devices have to do pixel doubling for 320x240 displays, would be correct to assume that a QVGA device will always outperform a VGA device when playing video at 320x240 ? (assuming same processor speed)

I have a Ipaq 4150 and hate the screen on it and after reading glowing reviews of the Asus A730 screen, I was considering switching to it. However, due to storage size, I would probably still encode my videos at 320x240 and am concerned by the performance hit of doing this.

Admittedly the Asus A730 has a slightly faster processor but is it enough to compensate ? Also if the A730 had the same speed processor, would the extra graphics chip be able to compensate ?

[Sven Johannsen]

from what I have read the VGA PPCs display the 320x480 in 1/4 of the screen . They don't double to fill the screen

[powerbook17]

from what I have read the VGA PPCs display the 320x480 in 1/4 of the screen . They don't double to fill the screen
Yes this is true but you mean 1/2 of the screen...1/4 would be 320x240

[wocket]

Betaplayer (http://betaplayer.corecodec.org/) works great in VGA. Also scales up your movies if you want (so many options) 8) .

[powerbook17]

bottom line wmp doesn't but there are third party ones that fill the screen

[Kati Compton]

Betaplayer (http://betaplayer.corecodec.org/) works great in VGA. Also scales up your movies if you want (so many options) 8) .
Right, the question is, is Betaplayer with a 320x240 movie significantly faster with a QVGA screen than when it is scaled up to fill a VGA screen?

[timmer]

Betaplayer (http://betaplayer.corecodec.org/) works great in VGA. Also scales up your movies if you want (so many options) 8) .
Right, the question is, is Betaplayer with a 320x240 movie significantly faster with a QVGA screen than when it is scaled up to fill a VGA screen?

I'd like to know this too. From a storage point of view, encoding videos at VGA res isnt going to be feasible for me as I am assuming quite a large increase in file size. But if I encode at 320x240 and it really slows Betaplayer down then I may be better of getting a QVGA device even though VGA would be nice for other things.

[wocket]

Betaplayer (http://betaplayer.corecodec.org/) works great in VGA. Also scales up your movies if you want (so many options) 8) .
Right, the question is, is Betaplayer with a 320x240 movie significantly faster with a QVGA screen than when it is scaled up to fill a VGA screen?

I've never noticed any performance problems at all and i'm just after checking. Both animation and live action movies all stored on a microdrive. Very good in either 640 x 480 portrait or scaled up to fullscreen landscape . I did'nt even pre-rotate the movies when I encoded them. I had the movies playing on a HP iPAq2210 and the Tosh E800 and the tosh does perform better.

As far as I am aware Picard the guy that wrote Betaplayer does all the decoding in software so I can't see a performance hit with the newer processors.

[timmer]

The scaling must be having some performance hit no matter how small. If you dont notice the difference its because, for example, without having to scale, it is using 80% of the CPU whereas with scaling its using 90% of the CPU.

So it wont make any noticeable difference to video playback but will be having a performance hit on the battery. More CPU power needed means more drain on the battery.

But it will be making a difference to the highest bitrate that can be used without skipping frames. As there will be very slightly less cycles per second available to decoding.

[picard]

There is a big difference between the scaling on the E800 and on the new VGA devices. E800 has ATI Imageon 3200 graphic chip which will do the scaling quite fast (with bilinear filter). On the other hand the new VGA devices don't have that kind of hardware acceleration. Still it can be quite fast to write 4x times more pixels, but there would a performace difference for sure. EXCEPT when someone (hopefully the OEM's) found a way to switch to true QVGA mode (and i don't mean reseting the device, but only for the time while the video player or game is in fullscreen). I think this would be best solution, no performance loss at all (maybe still not X30's speed, but close)

ps: the same goes for QVGA games.

[powerbook17]

There is a big difference between the scaling on the E800 and on the new VGA devices. E800 has ATI Imageon 3200 graphic chip which will do the scaling quite fast (with bilinear filter). On the other hand the new VGA devices don't have that kind of hardware acceleration. Still it can be quite fast to write 4x times more pixels, but there would a performace difference for sure. EXCEPT when someone (hopefully the OEM's) found a way to switch to true QVGA mode (and i don't mean reseting the device, but only for the time while the video player or game is in fullscreen). I think this would be best solution, no performance loss at all (maybe still not X30's speed, but close)

ps: the same goes for QVGA games.
im not sure about the ati graphics chip on the e800. My opinion is that they only put it on there so people can use it with a projector. The reason i say this is because the pdagold review benchmarks had the e800 at the bottom of the list

[picard]

im not sure about the ati graphics chip on the e800. My opinion is that they only put it on there so people can use it with a projector. The reason i say this is because the pdagold review benchmarks had the e800 at the bottom of the list
This is different. The benchmark was intended for QVGA. On VGA devices WM2003 SecondEdition zooms 200% the QVGA applications by an unoptimized very slow code by MS ( checkout this thread: http://www.pocketpcthoughts.com/forums/viewtopic.php?t=30934 or pre-production Asus A730 benchmarks ).

Movie playback is a different matter. BetaPlayer, PocketTV and PocketMVP are all using the ATI Imageon capabilites (hardware accelerated movie decoding and scaling to fullscreen).

I think the external display uses a different chip. This is why no movie playback acceleration possible on it.

[timmer]

If I'm going to encode my video at 320x240 regardless of whether I have a QVGA or VGA device would I be better off with a QVGA device ?

I wanted a VGA screen but if its going to have a large performance hit then maybe I wont. If it does then the Axim X30 suddenly seems like a good bet rather than getting a VGA device.

I was considering either the Asus A730 or Ipaq hx4705 but if these arent going to play video as well then thats a major disadvantage for me.

[picard]

I think the performance will be very much acceptable. Example i'am certain it will be faster to watch QVGA movies on the new VGA devices as on a QVGA Ipaq h2210 and it will be slower as on X30 High (but the difference is not known yet). With divx/xvid movies X30 High is way much faster as the required speed for rational bitrate QVGA movies (and the players are not WMMX optimized yet...) VGA has many other advantages, example browsing or worksheets or document reading and such.

[The PocketTV Team]

Movie playback is a different matter. BetaPlayer, PocketTV and PocketMVP are all using the ATI Imageon capabilites (hardware accelerated movie decoding and scaling to fullscreen).

I think the external display uses a different chip. This is why no movie playback acceleration possible on it.
That's correct, external display on the e800 series does not use the ATI Chip, it uses another video controler with no acceleration.

I think that Picard is correct. Personally I would also recommend getting a VGA device. Video players will certainely get acceptable performances when playing QVGA video on those devices. Whether they just do pixel-doubling or some more advanced interpolation will certainely change the performance, but there are many other factors, i.e. whether optimized WMMX libraries can be used etc.

Software will get better on the new devices, so I would go for VGA, it makes a big difference for web browsing and document reading, too.

[jeffmd]

pixle doubling to vga should take very little cpu since it is the simplist of math equasions to do. That combined with the fact most vga PPC's have a faster cpu then most QVGA ppc's, and you should allways get better playback performance reguardless on VGA pocket pc's.

[The PocketTV Team]

pixle doubling to vga should take very little cpu since it is the simplist of math equasions to do. That combined with the fact most vga PPC's have a faster cpu then most QVGA ppc's, and you should allways get better playback performance reguardless on VGA pocket pc's.The problem is not the compexity of the math, but rather the memory bandwidth. But apparently the memory bandwidth of the video frame buffer is high enough on the new VGA devices, so it should not be a problem.