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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: klx300r on December 14, 2010, 03:42:13 PM
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I hope this goes for all Sam owners, but the recent updates by ACube have totally removed all slight glitches and audio timing issues from my system..actually there were only a few DVD's that had this issue before but now they are completely ok...thanks ACube (http://amigaworld.net/images/smilies/icon_drink.gif)
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I hope this goes for all Sam owners, but the recent updates by ACube have totally removed all slight glitches and audio timing issues from my system..actually there were only a few DVD's that had this issue before but now they are completely ok...thanks ACube
Good news for Sam owners! :)
But isn't the Sam CPU too weak to play all DVD streams without frame skipping anyways?
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@ takemehomegrandma
I think that's the case with early Sam's (non flex) @533 Mhz and 667 Mhz as I'ver never had such frame skipping issues with my Samflex@800
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Good news for Sam owners! :)
But isn't the Sam CPU too weak to play all DVD streams without frame skipping anyways?
I don't see why. I believe I was watching DVDs on an Athlon 650Mhz way back in the day... Clearly it seems like the PCI bus r/w speeds were the issue here.
Good news for all.
Perhaps new benchmarks will be posted when comparing speeds of various OS' and applications.
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"I'ver never had such frame skipping issues with my Samflex@800 "
Yeah just don't try doing anything else, especially not anything really high tech, cutting edge and cpu intensive, like a text editor :)
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I too would have thought this problem was related to limited CPU power. X86 PCs benefit from GPU assisted decoding, but Amiga related systems do all video encoding/decoding with the CPU alone.
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I don't see why.
Well, it would be because the Sam CPU is a very low performing and weak "G2" class CPU, never really intended for desktop or media usage.
Nice to see Acube releasing bug fixes though! :)
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Well, it would be because the Sam CPU is a very low performing and weak "G2" class CPU, never really intended for desktop or media usage.
Nice to see Acube releasing bug fixes though! :)
Hmmm I doubt a Trident video card with a mere 16MB of RAM had alot of acceleration going on. :)
Even the Gamebube (G3) @ 487MHz could do it. ;-)
http://en.wikipedia.org/wiki/Panasonic_Q
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Hmmm I doubt a Trident video card with a mere 16MB of RAM had alot of acceleration going on. :)
Even the Gamebube (G3) @ 487MHz could do it. ;-)
http://en.wikipedia.org/wiki/Panasonic_Q
No, I don't remember Trident video cards offering video encoding/decoding acceleration either. But who uses these cards anymore?
I think the oldest common cards are probably the Voodoo3s (unless you count legacy Amiga RTG cards).
What's your point?
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Hmmm I doubt a Trident video card with a mere 16MB of RAM had alot of acceleration going on. :)
Even the Gamebube (G3) @ 487MHz could do it. ;-)
http://en.wikipedia.org/wiki/Panasonic_Q
Point is you are comparing apples and oranges, and maybe you are also putting too much attention to clock frequencies? And who was speaking about HW acceleration in video cards?
A G3 is usually faster than a "G2", for some application more than others. AFAIK a Pegasos 2 G3 is faster than any Sam. And a G4 is even faster, especially the newer ones, and especially for applications where Altivec make sense. As a result, MorphOS on a Mac Mini 1.42GHz plays x.264 720p streams better than a Sam plays DVD streams. A difference in work task that is a magnitude greater than the difference in clock frequency (of course other things affects the results as well, such as bus speed, etc).
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As a result, MorphOS on a Mac Mini 1.42GHz plays x.264 720p streams better than a Sam plays DVD streams. A difference in work task that is a magnitude greater than the difference in clock frequency (of course other things affects the results as well, such as bus speed, etc).
Since you are bringing different hardware in for comparison, I see your puny mac mini and raise you my (now not so hot) Q9450 with fully hardware-accelerated video decoding courtesy of nVidia's proprietary X drivers, which handles multiple 1080p streams no sweat at all :lol:
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Point is you are comparing apples and oranges, and maybe you are also putting too much attention to clock frequencies? And who was speaking about HW acceleration in video cards?
A G3 is usually faster than a "G2", for some application more than others. AFAIK a Pegasos 2 G3 is faster than any Sam. And a G4 is even faster, especially the newer ones, and especially for applications where Altivec make sense. As a result, MorphOS on a Mac Mini 1.42GHz plays x.264 720p streams better than a Sam plays DVD streams. A difference in work task that is a magnitude greater than the difference in clock frequency (of course other things affects the results as well, such as bus speed, etc).
Is a SAM considered a G2? I don't think so. It has something like 6 years of newer tech and faster(and much more) main memory than a Gamecube which was a G3. http://www.anandtech.com/show/858/2
The GC did have an incredibly fast memory interface for it's time. Here ACUBE has fixed issues with moving memory hence the improved performance in DVD playback. And besides my point is that SAM does have enough cpu performance to do it and not to compare x86 to PPC.
The memory interface was clearly the problem here. SAM has a DDR(266) interface and my old PC was using SDR(100). SAM should be able to outperform an Athlon 650 on large memory intensive tasks such as DVD playback ... but it wasn't. I don't believe cpu performance has anything to do with it. Even a P2 can decode Divx(@ SD resultions which is what resolution DVD is)...
Interesting: I see here that A1 used PC-133 memory...
http://www.memoryx.net/amigaonexe.html
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Is a SAM considered a G2? I don't think so. It has something like 6 years of newer tech and faster(and much more) main memory than a Gamecube which was a G3.
Gekko has L2 cache and some SIMD instructions, both missing from the AMCC PPC440EP. While AMCC PPC440EP has some multimedia instructions they have little practical importance, while Gekko's SIMD is subset of altivec.
AMCC PPC440EP core is from 1999, same year as Gekko.
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Where does a first-generation Athlon 500MHz with a 16MB Voodoo 3 and Windows XP (on 128MB of RAM!) fit into this comparison? If that old system of mine could multitask and play DVDs, I think the Sam hardware can manage it. Any problems have to be software-/firmware-related.
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Since you are bringing different hardware in for comparison, I see your puny mac mini and raise you my (now not so hot) Q9450 with fully hardware-accelerated video decoding courtesy of nVidia's proprietary X drivers, which handles multiple 1080p streams no sweat at all :lol:
I'm sure it was also cheaper than the Sam, I know my PC was! One of the many strenghts with x86. But my Mac Mini was ahelluvalot cheaper than my PC, and it runs MorphOS! Not using it for 1080p movies though... :)
Anyway, I'm not the one using the "I was watching DVDs on an Athlon 650Mhz way back in the day ... Even the Gamebube (G3) @ 487MHz could do it ... Even a P2 can decode ... so surely the Sam can do it as well" logic in this discussion. Apples and oranges!
http://amigaworld.net/modules/newbb/viewtopic.php?topic_id=32872&forum=33
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Gekko has L2 cache and some SIMD instructions, both missing from the AMCC PPC440EP. While AMCC PPC440EP has some multimedia instructions they have little practical importance, while Gekko's SIMD is subset of altivec.
AMCC PPC440EP core is from 1999, same year as Gekko.
Yes, but I'll have to check with the Wii/GC community to see if they actually use that for their homebrew DVD player software, I'm sure the Panasonic Q was fully optimized. Parralelism does help but if you can't feed the cpu fast enough (as was the case with SAM) then it's all for naught. Improving the speed at which the cpu received data improved the performance here.
There were some performance benchmarks posted a while back regarding performance of the various PPC Amiga platforms and SAM(s) took a beating. Perhaps now, those need to be re-run. Many people have pointed out that MorphOS feels faster(than OS4) and this issue could be a major factor. Now that it has been resolved, perhaps MorphOS team will be satisfied with the performance of SAM and issue a port.
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The earliest computer I have that can play DVDs is my PowerMac G3 @ 350mhz, which I overclocked to 400mhz within a few months of buying the system in 1999.
DVDs played well under Mac OS 9 using with the assistance of whatever video card was in the Mac (I forget what). But I remember when I upgraded to the earliest version of Mac OS X, DVD hardware acceleration was not yet written for OS X and DVD playback was choppy. At some point OS X started supporting this feature and DVDs started playing without frame skips again.
I think this is where we are with the Sam440 and DVD playback. The CPU is having to do all the work without any assist from the video card. The best I've managed is 2% skipped frames with one version of DVPlayer and 5% with another on my Sam440ep-Flex @ 733mhz.
It's watchable but not not ideal. My Sam lives in a room full of computers capable of better DVD playback, so this feature is not going to see a lot of use anyhow.
I wonder how the Sam460ex will do with DVD playback.
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I'm sure it was also cheaper than the Sam, I know my PC was
Actually not. I built the system out of what was at the time rather high end parts and with an emphasis on durability; I didn't intend to upgrade for a few years.
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I'm sure it was also cheaper than the Sam, I know my PC was! One of the many strenghts with x86. But my Mac Mini was ahelluvalot cheaper than my PC, and it runs MorphOS! Not using it for 1080p movies though... :)
Anyway, I'm not the one using the "I was watching DVDs on an Athlon 650Mhz way back in the day ... Even the Gamebube (G3) @ 487MHz could do it ... Even a P2 can decode ... so surely the Sam can do it as well" logic in this discussion. Apples and oranges!
http://amigaworld.net/modules/newbb/viewtopic.php?topic_id=32872&forum=33
The issues with DVD on the SAM remaining are AC3 decoding and the graphics driver is not optimized for DVD playback. Onboard sound on PC's have been doing AC3 decoding for a long time now. SAM has a dsp but I doubt it's being taken advantage of. So it's not a lack of cpu power, it's a lack of proper drivers that take advantage of hardware.
I also rank an ATI 9600 > Gamecube Flipper gpu. So again, I don't believe SAM is lacking in anything but proper drivers.
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Gekko has L2 cache and some SIMD instructions, both missing from the AMCC PPC440EP. While AMCC PPC440EP has some multimedia instructions they have little practical importance, while Gekko's SIMD is subset of altivec.
AMCC PPC440EP core is from 1999, same year as Gekko.
Yes, the Peg, A1 and wait for it: Gamecube all used the 750CXe.
But remember, my idea was crazy. ;-)
Wii is rumored to use 750CL.
(yes, I know some models had a cpu socket for upgrades)
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The best I've managed is 2% skipped frames with one version of DVPlayer and 5% with another on my Sam440ep-Flex @ 733mhz.
It's watchable but not not ideal.
If you have a 2% frame drop at 50Hz this is slightly better than cinema (which is 24 fps). I have not measured my framedrops, but DVDs look fluid, even if I open OWB and some applications at 1280x1024x32 with compositing on. It seems however that DV-Player is taking about 70% CPU load on my Flex @ 800mhz.
And what is more: When DVPlayer is dropping frames it just continues without slowing down the system or becoming unresponsive. So I don´t see why some people gerealize this to: "You can´t watch DVDs on SAM." I can.
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If you have a 2% frame drop at 50Hz this is slightly better than cinema (which is 24 fps). I have not measured my framedrops, but DVDs look fluid, even if I open OWB and some applications at 1280x1024x32 with compositing on. It seems however that DV-Player is taking about 70% CPU load on my Flex @ 800mhz.
And what is more: When DVPlayer is dropping frames it just continues without slowing down the system or becoming unresponsive. So I don´t see why some people gerealize this to: "You can´t watch DVDs on SAM." I can.
Hey there... I've enjoyed your Samblog. :)
I can see the frame skipping when there is a lot of movement in the image, and it bothers me too much to use my Sam for DVD watching when I have other choices. But I can see how others would have different levels of tolerance. I wonder if it's really dropping only a frame at a time, because it seems I would not notice that. But it's very noticeable, as if several frames are being dropped at once.
I am watching Region 1 movies in NTSC @ 29.97 fps. Does that make a difference in performance? Do PAL DVDs play back smoother with DVPlayer?
My 2% percent fame drops are with the OEM version of DVPlayer that came with the OS. It's version .72. My registered version is .65 and suffers from 5% frame drops on my Sam. Is there a later version? I must contact the author.
By the way, I recently relocated my Sam440 board into a new case and in the process switched to a different brand of SATA optical drive. That made no difference.