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The Daredevil Camera

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Re: The Daredevil Camera

#61

Post by jdietrich »

Qworg wrote: post #36
nxzero wrote: post #21

Earlier quoted context omitted.

Isn't this exactly what sonar does? SOund Navigation And Ranging: https://en.m.wikipedia.org/wiki/Sonar

There ARE sonars that deliver an image. http://blueprintsubsea.com/starfish/images/sonar/452/sf452_s... That's just one example - look for side scan sonars for the earliest stuff ( https://en.wikipedia.org/wiki/Side-scan_sonar ) or sonar imaging for the latest stuff ( http://www.tritech.co.uk/product/gemini-720i-300m-multibeam-... )

Such systems are ubiquitous on commercial fishing vessels.

https://en.wikipedia.org/wiki/Fishfinder

Re: The Daredevil Camera

#62

Post by rasz_pl »

Artlav wrote: post #53
rasz_pl wrote: post #52

>Unfortunately, we are still talking about a total of 64 Mbps of data. That needs a USB 2.0 sampling board that would pull the data out of the cells over the bulk interface you mean a $10 EZ-USB FX2LP dongle? You might be interested in this https://sourceforge.net/p/manyears/wiki/Main_Page/ Im sure you know about SeeSV-S205, its basically the same thing, but polished and packaged neatly for FAT commercial customers (…

Interesting. Can it take 16 simultaneous SPI-like channels of data going at 40-ish MHz, and pack it into a USB uplink?

not 16, but 8 '40-ish MHz' should be no problem as long as you sync them. FX2LP gives you raw 8/16bit wide datapump in GPIF Mode mode, or a nice FPGA friendly fifo in Slave FIFO mode, you can sort your 'spi like' data streams out on the pc side later/in real time. and since modern PCs have at least 2 usb hosts you could use two FX2LPs for all 16 streams.

Modern i7 cpu has surprising amount of flops and could handle this no problem (not to mention modern gpus). Consider modifying one of your boards, instead, or in addition to doing fft on fpga try pumping raw data over usb to a PC, 64 3MHz PDM streams should be 25MB/s? comfortably within usb 2.0 limits. FX2LP breaks no sweat while pumping ~40MB/s

top ebay link $6 http://www.ebay.com/itm/CY7C68013A-56-EZ-USB-FX2LP-USB2-0-De... application: http://www.cypress.com/documentation/application-notes/an613...

Re: The Daredevil Camera

#63

Post by dharma1 »

bcherny wrote: post #30

This would be pretty powerful if you combine it with speech recognition. If you put this array in the middle of a crowded room, can you better tease apart different audio sources?

You can use the phase/timing information between different mics to separate sources, yes.

Interestingly it's also doable with a single mic - previously with algorithms like NMF and ICA, more recently with neural networks. Our brains do it very well so there is probably more to discover.

Google blind source separation or cocktail party problem if you want to find out more.

Re: The Daredevil Camera

#64

Post by dharma1 »

bcherny wrote: post #30

This would be pretty powerful if you combine it with speech recognition. If you put this array in the middle of a crowded room, can you better tease apart different audio sources?

You can use the phase/timing information between different mics to separate sources, yes.

Interestingly it's also doable with a single mic - previously with algorithms like NMF and ICA, more recently with neural networks. Our brains do it very well so there is probably more to discover.

Re: The Daredevil Camera

#65

Post by Artlav »

rasz_pl wrote: post #62
Artlav wrote: post #53

Earlier quoted context omitted.

Interesting. Can it take 16 simultaneous SPI-like channels of data going at 40-ish MHz, and pack it into a USB uplink?

not 16, but 8 '40-ish MHz' should be no problem as long as you sync them. FX2LP gives you raw 8/16bit wide datapump in GPIF Mode mode, or a nice FPGA friendly fifo in Slave FIFO mode, you can sort your 'spi like' data streams out on the pc side later/in real time. and since modern PCs have at least 2 usb hosts you could use two FX2LPs for all 16 streams. Modern i7 cpu has surprising amount of flops and could handle t…

> 64 3MHz PDM

That's "64 3MHz PDM" per cell, of which there should be 16. And, they have to be synced to a sub-microsecond precision.

Re: The Daredevil Camera

#66

Post by pizza »

kamaal wrote: post #43
visakanv wrote: post #17

Earlier quoted context omitted.

Right on. Reminds me of Richard Feynman or Steve Wozniak, the way they just casually talk about taking things apart and putting things together while following a curiosity on an adventure. This is representative of the sort of ethos that drew everyone here in the first place, I think.

Unfortunately once you touch this sort of high, the normal day job starts to looking boring.

But you inch closer towards a reality where there are alternatives to the boring normal day job

Re: The Daredevil Camera

#68

Post by rasz_pl »

Artlav wrote: post #65
rasz_pl wrote: post #62

Earlier quoted context omitted.

not 16, but 8 '40-ish MHz' should be no problem as long as you sync them. FX2LP gives you raw 8/16bit wide datapump in GPIF Mode mode, or a nice FPGA friendly fifo in Slave FIFO mode, you can sort your 'spi like' data streams out on the pc side later/in real time. and since modern PCs have at least 2 usb hosts you could use two FX2LPs for all 16 streams. Modern i7 cpu has surprising amount of flops and could handle t…

> 64 3MHz PDM That's "64 3MHz PDM" per cell, of which there should be 16. And, they have to be synced to a sub-microsecond precision.

hence 'modifying one of your boards', as an experiment. if it works to your liking then you could move to FX3, that one can pump 400MB/s of raw bytes over usb 3.0. and that is for processing raw stream all on PC side.

If all you want is the current setup then above is valid with 2x $6 modules.

Re: The Daredevil Camera

#70

Post by dmitrygr »

soheil wrote: post #40

I think the whole thing could be done pretty much all in software. Setup a bunch of phone numbers in Twilio, using a bunch of your friends iPhones, strategically located, call the numbers and process the data using Twilio API. Whatsapp or other real-time voice communication apps with an API may work too.

You'll never be able to collect phase shift info from such a setup. Not only will each phone's DSP algos delay the data, but the jitter in transmission and reception will just kill any chance of it working properly.
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