I'm actually aiming at a different goal. What I want to develop is a system that can be used in multiple ways, the two most interesting of which being the unlimited-way conference calling that I was talking about and also for streaming audio broadcasts. I want something that can carry high-quality sound, not specific to voice compression.
What makes this different from a shoutcast-type system is that the client gets to select both the audio format (MP3, Ogg, SHN, wav) and bitrate that they want to use. The client can do this for both their up-stream as well as their down-stream.
The server (in a conference calling set-up) accepts each incoming stream from the net, decodes your selected format into raw audio, mixes all the other decoded incoming streams together (excluding your own), encodes the mixdown to your selected format, and sends it back to you over the net.
In a broadcast session, the client and server agree on the client's download stream and start moving data (only one client uploads in a broadcast... all others are download only.)
One major drawbacks of this system is the amount of bandwidth that the central server must have. It has to establish "N * 2" data streams, where N is the number of clients connected. If you just want lo-fi speech, this isn't a terrible problem.
(Even on my crappy DSL, I could handle 12-16 people in a conference call, each one getting an 8kbps feed from my server.)
The other drawback is processing power. The server (in addition to the bandwidth load it is handling) also must decode "N" streams of audio, mix together "N" unique streams of audio, and then encode "N" mixdowns.
The mixing doesn't take much CPU power, but the MP3/OGG decoding and encoding might be problem.
This is exactly the basis of what I am working on, except that the client can define what kind of audio stream they want to send to the server, and what type of audio stream that want to get back from the server.
This allows each user to use as much bandwidth as they can afford for conference calling. Allow stereo mixes to be made of the individual incoming streams, and you can add spacial placement for each voice in the mix, making it easier to tell who is speaking.
i'm just snagged up right now in the process of trying to understand the MPG123 codec sources to get a good grasp on the MP3 aspect of this project.
The client/server stuff is easy... it's the encoding and decoding that I'm having trouble with.
I've been toying around with a streaming MP3 system that would allow for unlimited conference sessions to take place, even if the client is on a modem. great for team games, and you can use as low as 16kbps of your total bandwidth to do it.
The central server has to have some pretty processing power and bandwidth, but it'd work.
I can write the linux server and client, but I don't know anything about programming witht he soundcard in windows.
Plenty of companies have laid of employees. Redhat was one. Are they dead in the "Linux-business" arena?
Not quite yet, but they're getting there.
Out of the, oh... 30 or so immediate friends/co-workers that I can think of that use Linux, exactly 1 of them uses RedHat... and that's just because one co-worker gave it away to another co-worker one day. The original owner didn't like it.
Maybe it's just something strange about my circle of friends, but I don't see much RedHat on any boxen nowadays.
I had a friend working at Eazel, and he absolutely hated the place from day one. His stay only lasted about 6 or 7 months, and he bolted.
Let's see that's:
Not a pleasant place to work
laying off 50% of workforce
I guess the dotcom plague is everywhere.
SirPoopsalot
Re:Wouldn't it be easier to use The Bible
on
Anticryptography
·
· Score: 1
Plus... if we sent them a Bible, they would quickly judge our entire race as weak minded and commence plans to take over our beautiful planet, strip it of all natural resources, kill all the humans, and leave the planet a mere empty shell.
I am a hardware engineer. Moreover, I am a logic design engineer. I sit in front of my computer and write Verilog RTL all day.
Writing a verilog model of a piece of hardware in an open source style with a community of designers is completely possible. In fact, it would be very easy, but there are issues that have prevented this from actually taking off in any type of widespread fashion.
Getting the model and code together is not the problem. Organizing that code into a CVS structure for the open source community is also not a problem. It works just like software.
ISSUE NUMBER 1
I have worked with FPGAs from both Xilinx and Altera, and I don't think you are considering the drawbacks of these systems.
The main one of these is memory. Most FPGA design kits do not have any type of off-chip storage. (ie, no SRAM on the FPGA board.) This means that you are forced to store any variables and data either
in FPGA-based RAM arrays
in the host system's (ie, PC) memory
Anyone who has worked with FPGAs knows that you begin to lose a lot of your available resources as soon as you try to implement any kind of RAM in the gate array. This makes it not an attractive option.
The only other option then is to store the data used by the custom hardware in the system memory/disks. This will work, but it will means a hell of a lot of system CPUFPGA transactions. Slow and cumbersome, but workable.
Lets back off of the whole FPGA thing for now, because we don't really need any FPGA to come up with the design for some hardware.
It is possible to build the model only in Verilog (or VHDL). This can be simulated and debugged on a computer with the right tools. (There are free tools available out there for Linux for all of this.)
But... even though we could do this... what then? The project would have to be useful anough and draw enough interest for someone to foot the manufacturing bill. Either that, or it gets sold as a non-efficient FPGA-based design that the user has to compile and upload to the FPGA board.
The performance of this hardware would suck. It would need to built as an ASIC to work optimally.
ISSUE NUMBER 2
Even if someone does foot the bill for manufacturing, the performance would be horrible. The major reason for this is that the project is going to built on some type of silicon. What type? That all depends on who does the manufacturing.
Anyone who works in hardware design knows that many pieces of circuitry have to be tweaked depending on the electrical characteristics of the silicon. This would be a hinderance to an open source hardware project for which the contributers don't know anything about the silicon that will eventually house this device.
ISSUE NUMBER 3
Hardware clocking? Obviously, this thing will need some sort of clock in it to push it along and make it operate. What kind of clock? How fast?
This (again) is something that will depend on:
silicon characteristics
system architecture
If you don't know how much time you have to accomplish (for example) a binary comparison of two values, then you don't know how to build this comparator. Do you have enough time to do it all in one clock cycle? Does it need to accomplish the task across four clock cycles? I don't know. Neither will anybody else.
SUMMARY
Opensource designs are possible, but not easy, and not likely. There are so many aspects of the design that are directly influenced by the final materials, packaging, and system board, that it becomes too problematic with trying to develop a useful, stable, robust device.
A piece of software is not affected by the type of disk that it is stored on. A piece of hardware is influenced dramatically by the type of silicon it will be stored on.
Opensource hardware will never be.
SirPoopsalot To send me an email, remove the SPAM's and replace the -at- with @.
Wait a second... now that I see that you want to spend $1500 on just the audio system for you home theater, this receiver is exactlywhat you should buy.
As far a speakers are concerned, my roomate uses Klipsh for center, front, and rear speakers.
The sub that he has is from a company whose name eludes me at the moment.
Sir Poopsalot To send me an email, remove the SPAM's and replace the -at- with @.
Outlaw Aduio is the name of the company, and they make a VERY high quality (yes also relatively cheap) receiver that is totally perfect for home theater.
Here's their website... They only have a couple of products so far, and the receiver I'm talking about it on their main page. (These things have gone into back-order twice already... and they are getting outstanding reviews on several home theater discussion forums.)
This little puppy they're selling will blow the doors off of probably any top-of-the-line "big name" receiver out there.
My roommate pointed me to it because I wanted to pick up a really good receiver without spending the $1000 like he did on his receiver. My roommate is a SERIOUS audiophile, and has proven to me time after time that low-end professional audio equipment is always better than high-end comsumer brands.
This thing costs $600, and while this may be out of/.'s price window, I still wanted to point the community to one of the best deals out there.
Stay away from the major names. Major name = major price.
Sir Poopsalot To send me an email, remove the SPAM's and replace the -at- with @.
The very reason that so many plants are off line right now for maintenance is that they were used and
abused so heavily this summer. Many plants set records for consecutive days running, and this kind of
use takes its toll.
Also, during this time of year, we can normally count on about 3,000 MW of power to be imported
from the Midwest. However, this power is not currently available because of the very cold weather that
part of the country is experiencing.
Umm... so now you are agreeing with me that there *is* a power shortage? Thanks.... that's all I was trying to say in the first place.
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
God has nothing personal against Florida. Hell, that's where he gets most of his new tennants from.
I think that God hates George W. Bush and his whole family. That's why He chose Florida as the center of controversy. Take Georgie's presidency away from him in a legal battle in the state that is run by Georgie's brother Jebb. It makes the whole family look bad.
As far as California is concerned... God loves it. We're not sinking into the ocean, as most people think. The Earth's plates are moving in such a fashion that CA is actually movie up the coastline.
Pretty soon, we'll be next door neighbors to Oregon and Washington, which is a hell of a lot better than being neighbors with Nevada. God's doing Clifornia a favor.
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
Actually, the shutdown of these power plants is anything but mysterious. It's all over the papers, and has been for a few weeks.
What's happening in CA is that a large number of power plants have been temporarily shut down for massive revamping and improvements. This is to allow these power plants to operate more efficiently and to deal with the large demand for power in California (in particular, here in Silicon Valley.)
So... to put it rather bluntly... you were completely wrong. There is a power shortage right now, and it's actually worse than the summer time due to the non-mysterious shutdown of several power plants.
SirPoopsalot To send me an email, remove the SPAM's and replace the -at- with @.
Does this mean that I might get a little time off work?
I work in Campbell, CA (just a tad south of San Jose), and the power grid here sucks a big one anyway. In the summer, all of the AC units in the valley get turned on and...
BANG!
... the lights go out in Campbell, the generator comes on at work, and my UPS starts screaming at me to hurry up and stop whatever the hell I thought I was going to get done that day.
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
I already get my electricity from Greenmountain.Com, because they use renewable energy sources.... mostly.
Sometimes I feel guilty about the amount of juice I use up with my LAN at home, especially since the computers outnumber the people in my house by a ratio of 3:1.
But, if I'm getting my electricity from something like this (ie, 100% renewable and very abundant), then maybe that annoying voice in my mind will BACK THE HELL OFF and let me sleep better.
Great.... this is exactly what we need. Humans that live hundreds of years.
Our population problem is big enough now, and that's with most people never getting to really know their great-grandparents.
Imagine the over-crowding problem that we would have if everyone from the previous 12 generations in your family were still around.
No thanks... I'd rather live in a less populated world than have a beer in an extremely overflowing bar with my great-great-great-great-great-great-great-great-gr eat-great-great-grandfather.
According to/.'s article, when the subscription runs out, I can no longer create new documents.
So, what's to stop me from making a copy of an existing document, opening the original, wiping the contents clean, and creating a new document with different contents, and resaving it?
Like this:
I just create a document called GENERIC.DOC while my sunscription is still good. Open it, write something, save it. Copy GENRIC.DOC to FOO.DOC. Then I re-open GENERIC.DOC, wipe it clean, put in new contents, save it, and then copy GENRIC.DOC to FOO2.doc. GENERIC.DOC remains my valid, temporary, subscription-compatible document.
Later, rinse, repeat....
Now that it really matters, though. I use Linux, and last I checked, MS Office didn't run on that OS without using WINE or plex86.
(Some, such as Alpha, go to Herculean extremes with a
gigantic reorder buffer and a cache which allows four or five outstanding misses to pend while still allowing hits in
the cache.)
You want to hear Herculean?
The processor I am helping design allows this:
The 512kB L2-Data cache can have 16 outstanding misses while still servicing HITs and non-cacheable transactions.
The 512kB L2-Instruction cache can have 8 outstanding misses wile still servicing HITs and noncacheables.
The 64MB (!!) L3-Unified cache can have all 24 of the L2 misses also outstanding, while still servicing HITs, victims from the L2D cache, as well as copy-backs non-cacheables, system controller requests, and non-cacheable transactions.
Request order is not maintained, but rather we services the requests as soon as it is possible.
Sound like overkill? Maybe... but schemes like this explain why my company's 350MHz chips out-perform Sun's 450MHz equivalent. We spend a hell of lot less time accessing memory on the UPA interface, and we can more outstanding misses on that interface as well.
Latency and bandwidth go hand-in-hand. They affect one another directly.
If something is hogging the bandwidth of the RAM bus, this means that other requests for RAM access must be delayed until the hog is finished. This directly causes the latency of the of other request(s) to increase.
Developing an architecture that minimizes bandwidth usage and latency is really tricky, and you can end up with all kinds of crazy mechanisms and whacky access protocols to facillitate this.
SuSE Linux is your solid middle ground. They typically release right about the same time (as just as frequently) as RedHat, but their distros are sh*t-tons more stable.
SuSE rocks. My Website and LAN all runs SuSE... and it always will.
It's really not possible to do this anymore. With all of the advances that have been made, and all the variations that are available, the "standardized" name might very well be flat out hard to understand, or impossible to remember.
Inevitably, someone would nickname the thing, and we'd all be calling it by that nickname.
Remember 486/DX and 486/SX? Sure... it was simple then. One meant that it had a math co-processor, one meant that it didn't have the co-processor.
Heck.. even at that time, the use of the first digit in the processor number didn't mean all that much except "generation number". All that was important was the use of the "86" to denote architecture.
Then we tacked on the MMX to the name. Or 3dNow!. If this would have kept up, we would have horribly long processor names.
hmmm..... I'd rather just say "1GHz Thunderbird, please". I mean... if you really want to know all the nity-grity details, go to the manufacturer's website and look at the specs of the chip.
Slashdot Mirror
I'm actually aiming at a different goal. What I want to develop is a system that can be used in multiple ways, the two most interesting of which being the unlimited-way conference calling that I was talking about and also for streaming audio broadcasts. I want something that can carry high-quality sound, not specific to voice compression.
What makes this different from a shoutcast-type system is that the client gets to select both the audio format (MP3, Ogg, SHN, wav) and bitrate that they want to use. The client can do this for both their up-stream as well as their down-stream.
The server (in a conference calling set-up) accepts each incoming stream from the net, decodes your selected format into raw audio, mixes all the other decoded incoming streams together (excluding your own), encodes the mixdown to your selected format, and sends it back to you over the net.
In a broadcast session, the client and server agree on the client's download stream and start moving data (only one client uploads in a broadcast... all others are download only.)
One major drawbacks of this system is the amount of bandwidth that the central server must have. It has to establish "N * 2" data streams, where N is the number of clients connected. If you just want lo-fi speech, this isn't a terrible problem.
(Even on my crappy DSL, I could handle 12-16 people in a conference call, each one getting an 8kbps feed from my server.)
The other drawback is processing power. The server (in addition to the bandwidth load it is handling) also must decode "N" streams of audio, mix together "N" unique streams of audio, and then encode "N" mixdowns.
The mixing doesn't take much CPU power, but the MP3/OGG decoding and encoding might be problem.
-Sir Poopsalot
This is exactly the basis of what I am working on, except that the client can define what kind of audio stream they want to send to the server, and what type of audio stream that want to get back from the server.
This allows each user to use as much bandwidth as they can afford for conference calling. Allow stereo mixes to be made of the individual incoming streams, and you can add spacial placement for each voice in the mix, making it easier to tell who is speaking.
i'm just snagged up right now in the process of trying to understand the MPG123 codec sources to get a good grasp on the MP3 aspect of this project.
The client/server stuff is easy... it's the encoding and decoding that I'm having trouble with.
I've been toying around with a streaming MP3 system that would allow for unlimited conference sessions to take place, even if the client is on a modem. great for team games, and you can use as low as 16kbps of your total bandwidth to do it.
The central server has to have some pretty processing power and bandwidth, but it'd work.
I can write the linux server and client, but I don't know anything about programming witht he soundcard in windows.
Not quite yet, but they're getting there.
Out of the, oh... 30 or so immediate friends/co-workers that I can think of that use Linux, exactly 1 of them uses RedHat... and that's just because one co-worker gave it away to another co-worker one day. The original owner didn't like it.
Maybe it's just something strange about my circle of friends, but I don't see much RedHat on any boxen nowadays.
SirPoopsalot
Let's see that's:
I guess the dotcom plague is everywhere.
SirPoopsalot
Ummmm... wait....
I guess we beat them to that stuff already.
SirPoopsalot
Writing a verilog model of a piece of hardware in an open source style with a community of designers is completely possible. In fact, it would be very easy, but there are issues that have prevented this from actually taking off in any type of widespread fashion.
Getting the model and code together is not the problem. Organizing that code into a CVS structure for the open source community is also not a problem. It works just like software.
ISSUE NUMBER 1
I have worked with FPGAs from both Xilinx and Altera, and I don't think you are considering the drawbacks of these systems.
The main one of these is memory. Most FPGA design kits do not have any type of off-chip storage. (ie, no SRAM on the FPGA board.) This means that you are forced to store any variables and data either
Anyone who has worked with FPGAs knows that you begin to lose a lot of your available resources as soon as you try to implement any kind of RAM in the gate array. This makes it not an attractive option.
The only other option then is to store the data used by the custom hardware in the system memory/disks. This will work, but it will means a hell of a lot of system CPUFPGA transactions. Slow and cumbersome, but workable.
Lets back off of the whole FPGA thing for now, because we don't really need any FPGA to come up with the design for some hardware.
It is possible to build the model only in Verilog (or VHDL). This can be simulated and debugged on a computer with the right tools. (There are free tools available out there for Linux for all of this.)
But... even though we could do this... what then? The project would have to be useful anough and draw enough interest for someone to foot the manufacturing bill. Either that, or it gets sold as a non-efficient FPGA-based design that the user has to compile and upload to the FPGA board.
The performance of this hardware would suck. It would need to built as an ASIC to work optimally.
ISSUE NUMBER 2
Even if someone does foot the bill for manufacturing, the performance would be horrible. The major reason for this is that the project is going to built on some type of silicon. What type? That all depends on who does the manufacturing.
Anyone who works in hardware design knows that many pieces of circuitry have to be tweaked depending on the electrical characteristics of the silicon. This would be a hinderance to an open source hardware project for which the contributers don't know anything about the silicon that will eventually house this device.
ISSUE NUMBER 3
Hardware clocking? Obviously, this thing will need some sort of clock in it to push it along and make it operate. What kind of clock? How fast?
This (again) is something that will depend on:
- silicon characteristics
- system architecture
If you don't know how much time you have to accomplish (for example) a binary comparison of two values, then you don't know how to build this comparator. Do you have enough time to do it all in one clock cycle? Does it need to accomplish the task across four clock cycles? I don't know. Neither will anybody else.SUMMARY
Opensource designs are possible, but not easy, and not likely. There are so many aspects of the design that are directly influenced by the final materials, packaging, and system board, that it becomes too problematic with trying to develop a useful, stable, robust device.
A piece of software is not affected by the type of disk that it is stored on. A piece of hardware is influenced dramatically by the type of silicon it will be stored on.
Opensource hardware will never be.
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
As far a speakers are concerned, my roomate uses Klipsh for center, front, and rear speakers.
The sub that he has is from a company whose name eludes me at the moment.
Sir Poopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
Here's their website... They only have a couple of products so far, and the receiver I'm talking about it on their main page. (These things have gone into back-order twice already... and they are getting outstanding reviews on several home theater discussion forums.)
This little puppy they're selling will blow the doors off of probably any top-of-the-line "big name" receiver out there.
My roommate pointed me to it because I wanted to pick up a really good receiver without spending the $1000 like he did on his receiver. My roommate is a SERIOUS audiophile, and has proven to me time after time that low-end professional audio equipment is always better than high-end comsumer brands.
This thing costs $600, and while this may be out of /.'s price window, I still wanted to point the community to one of the best deals out there.
Stay away from the major names. Major name = major price.
Sir Poopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
Also, during this time of year, we can normally count on about 3,000 MW of power to be imported from the Midwest. However, this power is not currently available because of the very cold weather that part of the country is experiencing.
Umm... so now you are agreeing with me that there *is* a power shortage? Thanks.... that's all I was trying to say in the first place.
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
I think you meant to say "Last time I checked, California WAS next door to Oregon."
Wait! Was that comment from George W. Bush himself?! It looks exactly like his grammar style!
"Rarely is the question asked, are our children learning?" - George Bush
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
I think that God hates George W. Bush and his whole family. That's why He chose Florida as the center of controversy. Take Georgie's presidency away from him in a legal battle in the state that is run by Georgie's brother Jebb. It makes the whole family look bad.
As far as California is concerned... God loves it. We're not sinking into the ocean, as most people think. The Earth's plates are moving in such a fashion that CA is actually movie up the coastline.
Pretty soon, we'll be next door neighbors to Oregon and Washington, which is a hell of a lot better than being neighbors with Nevada. God's doing Clifornia a favor.
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
What's happening in CA is that a large number of power plants have been temporarily shut down for massive revamping and improvements. This is to allow these power plants to operate more efficiently and to deal with the large demand for power in California (in particular, here in Silicon Valley.)
So... to put it rather bluntly... you were completely wrong. There is a power shortage right now, and it's actually worse than the summer time due to the non-mysterious shutdown of several power plants.
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
I work in Campbell, CA (just a tad south of San Jose), and the power grid here sucks a big one anyway. In the summer, all of the AC units in the valley get turned on and...
BANG!
SirPoopsalot
To send me an email, remove the SPAM's and replace the -at- with @.
I wrote a research paper waaaaaaaay back in highschool (circa 1990) about sleep and dreams.
All of the information in that article was readily available 10 years ago in textbooks that were printed 30 years ago.
I'd hardly call this news.
SirPoopsalot
One really big one.
Sometimes I feel guilty about the amount of juice I use up with my LAN at home, especially since the computers outnumber the people in my house by a ratio of 3:1.
But, if I'm getting my electricity from something like this (ie, 100% renewable and very abundant), then maybe that annoying voice in my mind will BACK THE HELL OFF and let me sleep better.
SirPoopsalot
PS: first *real* post?
Our population problem is big enough now, and that's with most people never getting to really know their great-grandparents.
Imagine the over-crowding problem that we would have if everyone from the previous 12 generations in your family were still around.
No thanks... I'd rather live in a less populated world than have a beer in an extremely overflowing bar with my great-great-great-great-great-great-great-great-gr eat-great-great-grandfather.
So, what's to stop me from making a copy of an existing document, opening the original, wiping the contents clean, and creating a new document with different contents, and resaving it?
Like this:
I just create a document called GENERIC.DOC while my sunscription is still good. Open it, write something, save it. Copy GENRIC.DOC to FOO.DOC. Then I re-open GENERIC.DOC, wipe it clean, put in new contents, save it, and then copy GENRIC.DOC to FOO2.doc. GENERIC.DOC remains my valid, temporary, subscription-compatible document.
Later, rinse, repeat....
Now that it really matters, though. I use Linux, and last I checked, MS Office didn't run on that OS without using WINE or plex86.
But... wouldn't this work?
SirPoosalot
You better get busy.
You want to hear Herculean?
The processor I am helping design allows this:
Sound like overkill? Maybe... but schemes like this explain why my company's 350MHz chips out-perform Sun's 450MHz equivalent. We spend a hell of lot less time accessing memory on the UPA interface, and we can more outstanding misses on that interface as well.
SirPoopsalot
HAL Computer Systems
If something is hogging the bandwidth of the RAM bus, this means that other requests for RAM access must be delayed until the hog is finished. This directly causes the latency of the of other request(s) to increase.
Developing an architecture that minimizes bandwidth usage and latency is really tricky, and you can end up with all kinds of crazy mechanisms and whacky access protocols to facillitate this.
SirPoopsalot
SPARC64 L3 Cache Architect
HAL Computer Systems
SuSE rocks. My Website and LAN all runs SuSE... and it always will.
-SirPoopsalot
With systems as fast as these (or with anything over 600 MHz), fps won't really tell you much.
Sir Poopsalot
Inevitably, someone would nickname the thing, and we'd all be calling it by that nickname.
Remember 486/DX and 486/SX? Sure... it was simple then. One meant that it had a math co-processor, one meant that it didn't have the co-processor.
Heck.. even at that time, the use of the first digit in the processor number didn't mean all that much except "generation number". All that was important was the use of the "86" to denote architecture.
Then we tacked on the MMX to the name. Or 3dNow!. If this would have kept up, we would have horribly long processor names.
For example, a Tbird would now be called a:
x86-3dnow/MMX-l1u$128k_1:1-l2u$256_1:1k-200Mhzfsb- SDR-1GHz
Which means:
hmmm..... I'd rather just say "1GHz Thunderbird, please". I mean... if you really want to know all the nity-grity details, go to the manufacturer's website and look at the specs of the chip.
Sir Poopsalot