From The latest Video editing article:

"For example: we often use an Intel Pentium 4/2000 clocked to 2300 MHz for MPEG-4 encoding, together with 512 MB of RAM and a fast Ultra-160-SCSI hard drive. That means that for full PAL resolution (720 x 576 dots) and sound with 128 KBit/s at 44 kHz, a frame rate of only about 19 images per second is reached, and the results should be similar for NTSC encoding too"

I assume this means that it's encoding at roughly 2/3 the speed it takes to play the video, is that correct?


In either case, i'm wondering what i can be cheap on and get comparable performance? ideally the SCSI drives would be first to go, but if that will knock down the performace by a LOT, then i wouldn't consider it. Advice?

Also would 1g ram be a big improvement over 512, or a waste of money?

1. your assumption is correct. the stated framerate means how many frames per second are proccessed. 25fps would means realtime for PAL.

2. the main, and more or less only, part that influences the conversion speed is the CPU. and there it is the FPU part that should be fast. the P4 looks good speedwise since there is a special version of Flask that makes use of the SSE2 instructions. but a P4 2Ghz is very expensive.
a newer Athlon XP with some DDR-ram should be much easier on the wallet and with the right version of Flask (to get at www.doom9.org) should give similar results speedwise.

3. the harddrive speed is not very important. just think how much data has to be written at 19fps? not that much. any modern IDE HD will do w/o any noticeable difference unless you have some harddrive heavy tasks running while running Flask. but than again you won't run any other apps or tasks when conversion speed is paramount.
a SCSI drive is definitely not neccessary.

4. 512MB ram should be enough. even 256MB should do nicely but why not 512 since it is so cheap. 1GB should show no speed improvement.
more important is the RAM type. fast DDR-Ram and a CPU bus speed of 133Mhz (in case of an Athlon or PIII) are speedier than SD-RAM and 100Mhz CPU bus speed.
RD-RAM has a good speed too but is expensive and can only be used in a P4 system.

if your are on a tight budget I would suggest you go with an Athlon XP system with DDR-Ram. even the fastet Athlon CPU is much cheaper than the fastet P4 and beats or scores even with the P4 in a lot of apps. add a fast IDE HD with 7,200 RPM and good capacity and you will do fine.

respect!

On the Athlon bit - I bought an Athlon 1400C. True, it doesn't have a Palomino core, but it's still a solid monster. I also gave it an Asus A7M266 mobo and 128MB DDR (I keep an eye on mem usage, I don't exceed 128M, so no swap is involved), which is the best chipset I managed to acquire at the time. All that gave me 11 FPS (without deinterlacing, WITH deinterlacing I drop to roughly 9).
So in this, I *THINK* a P4 is stronger, even with Athlon's own iDCT. My athlon solution cost around 140$CPU+170$Mobo+35$RAM. Compare that with either a low-end P4 that will cost you slightly more (~200+170+35) for the same frame rate, a high-end P4 (~500$CPU+170$MoBo+50$RDRAM) that will give you ~15-16. And you can overclock all the above for a ~3-4fps increase (Like THG did with the P42Gig to 2.3Gig), enspecially if you have a fast athlon and an industrial-sized nuclear-reactor-cooler.

Regarding the HD not being important bit, I also thought that until I realized something small but important. Yes, it has to WRITE OUT a 700MB file over the course of 5 hours encoding. you don't need a fast disk for that.
*BUT*
It needs to read 7 gigs of VOB during that time too. Now THAT takes some time. and a speedy disk *MIGHT* (I say might because ideally if you do good caching, the reading is done while the CPU is grinding bits and you don't take more time in the overall, but that's in an ideal world) improve performance.
Memory: I checked flask before buying RAM. It eats about 15-20 Megs while working. All you I-Need-A-Mountain-Of-Ram freaks calm down. Windows XP professional with Flask encoding AND CLAD Ripping at the same time don't take more than 128 Megs. So unless budget is not an issue, this is thrown-away money.

I Did notice a noticeable encoding speed difference between an Athlon850(SDR-SDRAM) and an Athlon1400C (DDR-SDRAM) that is more significant than the clock-speed ratio (some speed difference is also owed to a better chipset - the former is an old A7V, the latter is an A7M266). In short, since encoding DivX's is moving a bunch of numbers around, memory speed plays a crucial role. Don't settle for less than PC2100 or RDRAM. By the way, there's non-intel chipsets for P4. One (The SiS I think?) uses DDR333. And that might be both cheap and fast.

In short, If you're looking to buy THE FASTEST thing around, buy a P4/2Gig, put it in a 600$ AseTek case, vaporchill it to -20degrees celcius and run it at 2300-2500MHz like THG do with theirs. A similar Athlon solution (using the new Palomino-Core XP1800+ that runs at 1533MHz) and a heavy-duty MoBo chipset like the Via KT266A, should wield 90-100% the performance at roughly 50% the price.

Your call from here :-)

I would nix SCSI first. SCSI is nice but not really worth the extra $$. I've got a SCSI system and everything costs more. As far as DVDs go SCSI is a generation behind so IDE is actually faster.

AMD now has SSE as part of their 3dnow professional. The XP would be actually faster and cheaper then a p4. I have a p4 1.3GHZ with 128MB RD-800 and it does about 15fps with a 7200 rpm IDE drive. That spec is for wide screen movies at a resolution of 720 by around 350 so it is not a direct comparison to the review in Tom's. If you do the math you will find that even with the slower HD and less RAM I'm still at a good fraction as fast as Tom's system reletive to CPU speed.

Check out this review of AMD XPs doing Flask.<A HREF="http://www.anandtech.com/cpu/showdoc.html?i=1543&p=9" target="_new">link to test</A>

Remember if you ain't Muslim you ain't Shiite.

NermalDude

I got side tracked tonight and actually had to work at work so you posted while I was writing mine. Good advice as always.

Remember if you ain't Muslim you ain't Shiite.

The 11 fps without deinter seem a little low for me. I have a tbird 1.4 (o/c to 1500 (150x10)) in a MSI Pro2 (KT266A), 512 ram and i have 17-18 fps and 12-13 with deinter. I am using Flasmpeg 0.6 and DivX 4.02. Have you downloaded the latest divx codecs?

The fast hard drives only coming into concideration when you need a massive data rate. This is normaly require in the capturing and editing stages.
In the case of encoding material into Mpg4/DviX Hard drives the concideration is CPU and memory tech. Not much of the memory size after you are over the 256MB.