Comparing CPU requirements for CODECs

[rhsmith]

Greetings!

I must prepare some video stuff for use across a variety of laptops, some of which were purchased with the optional coal chute and auxiliary boiler. I am discovering that many modern video Codecs, i.e., MPeG2 or IV5 require a modern (PII or equiv) CPU to run better than 1 frame per month as I'm seeing on the aforementioned antiques.

Has anyone heard of a chart showing the requirements for hardware/software for the various codecs available? Or am I making one ?

(On a side note does any know the MSRP for the RT2000?)

Merci buckets,

Richard Smith

------------------
BH6/300a@450/128MB
Maxtor 17.2GB/
GXP 10GB/Fireball KA on
FastTrack66/Marvel G200/
MX300

[Grigory]

For laptops, there are three major problems:
1. Hard drive speed.
2. CPU speed.
3. Video card speed.

#1 is of most importance for the codec that produce high data rate video. Note, this video may be not CPU demanding. Indeo 5 is an example. You may encounter playback problems just because your old energy-saving laptop hard drive cannot retrieve data at >600 Kb/sec sustained data rate. Indeo files must play well on P200 MMX cpu. MMX is a MUST. Remember - Indeo is Intel codec.

#2. Modern codecs like Mpeg 2 and 4 are very CPU demanding. Mpeg 2 is not for old notebooks at all. Mpeg 4 can easily drop frames on PII 350 with only 352x288@25 fps, if the data rate exceeds 3000 kbit/sec. Limiting it at 1000 kbit/sec gives better results, but you have to check on the slowest notebook and, of course, accept lower quality.

#3 is important for any codec and any video of large frame size in pixels by FPS multiple. Some codecs are optimized for DirectDraw data transfers in one of YUV formats. If the card does not support this format, CPU power is used for transcoding into RGB or another acceptable format. This may take a lot of CPU power.

So, for each PC you may have different reasons of low fps.
In general:
1. Find a codec that has the lowest CPU utilization at acceptable quality, regardless of data rate. Try to check it with old video card, say S3 Trio 64 or Trident 9440 on desktop PC. You can probably buy these cards for $10. Make tests at the highest possible color depth, and better with 1MB video RAM cards. This ensures that your video has the lowest demand for CPU and video hardware.

ISA video cards are even better for tests.

2. Try to play video over slow data transfer channel - network or ancient 200 MB hard drive. Samsung is the "best" choice. You must also try this drive in PIO 0 mode. Internal IDE or even LPT ZIP drive is good for tests, too.

Finally you can probably find the best codec - MPEG1.
I remember the time when MPEG1 played well on P100 from ZIP drive on S3 TRIO 64 PCI video card in full screen 800x600 hi-color.

Forget about 486.

Grigory

[rhsmith]

Thank you Grigory!

Hmmm, off a Zip drive eh? And probably a parallel port at that!

I'll have to give MPeg1 a try.

Any recommendations on a (cheap) encoder?

Thanks again,

Richard Smith