04-16-2013, 01:16 PM
Then buy an Broadcom CrystalHD card. Its cheaper and need much less W/h
Originally Posted by brosis
04-16-2013, 01:18 PM
04-16-2013, 05:59 PM
04-18-2013, 12:12 PM
Lets be a little bit nicer and explain the units rather than just screaming "WRONG".
Originally Posted by stqn
Energy is measured in a unit called JOULES (J).
A WATT (W) is the RATE of energy transfer (because energy can be neither created nor destroyed, you can do nothing besides transfer it).
1 W = 1 J/s <--- that is Joule per SECOND, clearly the rate of transfer of energy.
We can play with the time unit a bit to bring it to HOUR....
1 W = 60 J/m
1 W = 3600 J/h <--- now we can see what a watt is in terms of HOURS.
To picture this best, imagine a boat that has been sitting in the rain. It is partly full of water (Joules).
So you can think of JOULES in similar terms as "gallons of water".
Now you have a bucket, you need to empty that water out, so you hop in the boat and start bailing. You scoop up that water and pour it over the side of the boat.
How much time does it take you to bail out all of the water from the boat? That's WATTS. How fast you transfer that water out of the boat.
Moving those units around a little bit to give another familiar unit, we can see something like this;
1 W x 1 h = (3600 J / h) x 1h
1 W.h = 3600 J <--- 1 WATT-HOUR = 3600 JOULES.
When you pay for electricity delivered to your home, it is usually charged per KILOWATT-HOUR. kWh. This is just a convention to make the units look more familiar with respect to things like light bulbs and stove burners, which are described in watts, than it would be if measured in Joules.
1 kWh = 3,600,000 J <--- 1 kWh equals 3.6 million JOULES.
NOW, the inapplicable unit in question... W/h.....
W/h would be J/h/h <--- Joules per hour, per hour. This would be a RATE OF CHANGE OF RATE.
So for example, you have a rain barrel that drives a turbine. The deeper the water is in the rain barrel, the more pressure it outputs, and therefore the more energy you can transfer out of the turbine. Starting with an empty barrel, your transfer rate is 0 W. But it is raining, and filling your barrel at a rate that you measure to increase your energy transfer rate by 2 W/h.
After it has been raining for 1 h, the water is deep enough to transfer 0 W + (1 h x 2 W/h) = 2 W.
After it has been raining for 2 h, the water is deep enough to transfer 0 W + (2 h x 2 W/h) = 4 W, ****OR**** 2 W + (1 h x 2 W/h) = 4 W, depending on whether you are adding one incremental hour, or calculating from the start.
3 h --> 6 W,
4 h --> 8 W,
If you want to run a 60 watt light bulb off that, you're going to need a pretty tall barrel, and wait 30 hours for it to fill deep enough to generate enough pressure.
Last edited by droidhacker; 04-18-2013 at 12:17 PM.
04-18-2013, 12:49 PM
Just for my own edification, um How then would you describe voltage and current. wattage is equal to voltage x current if 1W = 1J/s then how does currrent and voltage work its way in? Is voltage x current just simply a different way of stating J/s?
Originally Posted by droidhacker
04-18-2013, 01:12 PM
Originally Posted by duby229
Joule is a unit of energy. You can move charge over a difference in electric potential (electrical definition with Volts and Coulombs), or you can move weight over a difference of (say) height potential (physical definition with kgs and metres). Both require energy.
04-18-2013, 01:41 PM
AMD marketing materials usally include or reference a quality guarantee. IOW, we don't guarantee quality above 1HD + 1SD (for a particular configuration of hardware, OS, and driver). You can decode more streams but we don't make any quality gurarantees so you may experience dropped frames, jitter, etc. For some applications (security cameras, pure decoding/transcoding to a file), quality is not important so you may not care. Of course, we don't make any guarantees witjh respect to the open source implementation so YMMV but the marketing materials are a useful guide for what you can reasonably expect.
Originally Posted by chithanh
04-18-2013, 02:23 PM
Hi Tim. I can think of one example where hi quality encodes will matter. I have a camera pointed down at the cash register drawer. Whenever i get 50s or 100s I flip through them in front of the camera in a way for it to see the serial number. Plus I have lower resolution camera pointed at the counter and another pointed at the entrance. Of course all that encoding is being done in software right now.
Originally Posted by twriter
04-18-2013, 03:52 PM
He didn't say that NO security applications require high quality, but suggested that SOME DON'T.
Originally Posted by duby229
04-18-2013, 04:14 PM
I believe Tim was also talking about decode, not encode.