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-   -   New DIY HD Cinema Camera Project (https://www.dvinfo.net/forum/alternative-imaging-methods/96349-new-diy-hd-cinema-camera-project.html)

Bob Tasa October 16th, 2007 05:23 AM

Just a little about me.
I am a windows programmer by trade and been writting plugins for
video applications part time. Been wanting an HD camera for a long
time but the only one that seems to be worth having is the
RED which is WAY out of my price point. So I am very interested in
this project. What is the total cost you are trying to stay
under?

Thanks,
Bob

Alex Stewart October 18th, 2007 12:43 PM

Im trying to shoot for under $600 for this project.
That includes some nifty LCD's :-)

The JPEG2000 codec is what Im planning on using as a lossless compressor to squish this stream into something manageable.

David Delaney October 19th, 2007 03:08 PM

This will make things easier for swapping large files :
http://www.geekstuff4u.com/product_i...roducts_id=630

I can't wait to get one.

Bob Tasa October 19th, 2007 04:05 PM

First cool idea with the sata drive mounts. Wonder if you can use a battery?

> The JPEG2000 codec is what Im planning on using as
> a lossless compressor to squish this stream into
> something manageable

Dont squish the video too much. HD is ~166MB/sec raw.
If you squish it to much you artifact the data.
27MB/sec which is ~6 to 1 and considered almost loseless.

If would be interesting to have options open so that you
can reduce or increase the amount of compression if
thats at all possible.

Have you actually gotten an image from this sensor yet?

Bob

(PS. 600 WOW that cheap?? )

Take Vos October 20th, 2007 01:01 AM

Too bad that HDD stack thingy doesn't come in an eSATA model. That would have been perfect.

David Delaney October 20th, 2007 07:35 AM

I am sure it won't be long for the eSATA model. Or maybe someone will mod one of these things.

Alex Stewart October 23rd, 2007 10:06 AM

Quote:

Originally Posted by Bob Tasa (Post 761583)
First cool idea with the sata drive mounts. Wonder if you can use a battery?

> The JPEG2000 codec is what Im planning on using as
> a lossless compressor to squish this stream into
> something manageable

Dont squish the video too much. HD is ~166MB/sec raw.
If you squish it to much you artifact the data.
27MB/sec which is ~6 to 1 and considered almost loseless.

If would be interesting to have options open so that you
can reduce or increase the amount of compression if
thats at all possible.

Have you actually gotten an image from this sensor yet?

Bob

(PS. 600 WOW that cheap?? )

The Image sensor is going to output in Bayer format.
So at 720p we get:
1280x720 = 921600 pixels, which are 10bits each on this sensor so
x10 = 9216000 bits /8 to put it into bytes of 8 bits = 1152000 Bytes / 1024 bytes per k = 1125 KB per frame. At 24p we get 27000KB or ~ 27MBps
And that is raw video no compression at all. Ill admit that with bayer we are interpolating pixels, but with the proper conversion the law of averages says we'll get about the right color. And since the imager is 3MP and we can window were the 1280x720 is - we can center it, thus having pixels above and below and to the left and right so we can extract bayer pixels for the full image.

Also, I chose the imager because its obtainable (got mine from digikey). Also its a CMOS imager, not CCD. ~166MB/s raw is if you have 3 CCD's for each color.... which would also mean $1200 just for the imagers.

PS - I just got word from Hong Kong, the Head board PCB Im testing the imager out on that will hook to the Altera Dev kit is being Fabbed, should be here soon.

Bob Tasa October 23rd, 2007 02:17 PM

Thanks for the answers to the questions. Is this the way other cameras
do this? Like still cameras? Just curious. I read up on the Bayer pixel color pattern. If someone has not done this already you should be able to write
something to translate the raw bayer data straight to video because converting it to YUV or some other color format will actually increase
the size wont it?

Just thinking. Only 27MB/sec cool.. You might have to have a pair of
Sata drives to capture continuosly but it could be done.

I work a lot with 22MB/sec YUV 4:2:2 data mixing the streams as well
as reading and writting files.

I could see that with 3 sensors the entire project becomes much more complex and expensive. You have to split the image into RGB which makes
alignment and issue then time the reads of each sensor. Just
more complex.

Just some random thoughts.

Steven Mingam October 23rd, 2007 03:03 PM

Quote:

Originally Posted by Alex Stewart (Post 763308)
we can center it, thus having pixels above and below and to the left and right so we can extract bayer pixels for the full image.

PS - I just got word from Hong Kong, the Head board PCB Im testing the imager out on that will hook to the Altera Dev kit is being Fabbed, should be here soon.

Actually, CMOS sensors (at least my 1.3Mp Micron sensor) offer a slighty bigger image with 4 pixels more (2 on each side) for the interpolation.
(well yes it's irrevelant because the full sensor is too slow anyway)

Good news for your sensor board, if you don't mind, can you talk about the price ? I've absolutly no idea how much cost a prototype PCB (and i'll need one for my full camera)
By the way, I got my first picture today, w00t \o/

@Bob : we already discussed at length of debayering methods, try to look into this thread, and into Take Vos Mirage's thread ;)

Alex Stewart October 24th, 2007 11:18 AM

PCB cost will depend on how many layers you end up needing, and the square inch size of the board. My sensor head was simple (2 layers) and fairly small, so I got away with ordering 3 for ~$70

I would imagine however you will likely need at least 4 layers, and a fair bit of board space... so Id guess $200-300 for ~3-4 boards...

-Alex

Congrats on the first picture!
Hopefully Ill be at that stage soon too.

Anmol Mishra October 26th, 2007 09:33 AM

VGA to GigE Vision or IIDC converter ??
 
On the topic of Pleora boards and the like - there are tons of high quality VGA machine vision cameras lying around... Has anyone worked on a RGB to GigE Vision or IIDC converter ?
Just wondering what it would take - perhaps I could try attempt one myself..


Quote:

Originally Posted by Seth Kersey (Post 717307)
Isn't that 56 MB/s or am I calculating wrong?

Some 2.5" SATA drives can reach 56 MB/s, but only as burst not sustained write speeds.

I believe the best average write speed is about 44 MB/s, will that work with lossless compression so no RAID is needed?


That Pleora board only works with parallel data, maybe they have something else that uses serial... because the Micron is serial, I think?

EDIT: I tried browsing the Micron Datasheet, but I am still unsure if that Pleora will or will not interface.

Does anyone know how the Micron head board interfaces with the dev board?


Anmol Mishra October 27th, 2007 11:03 AM

Changing mouse settings on linux
 
FYI - Linux allows USB on steroids too :-)
http://www.linux-gamers.net/modules/...WTO+USBPolling

Windows utility is called USB Mouserate switcher.

David Delaney November 7th, 2007 06:13 PM

A very small PC - looks promising.

http://translate.google.com/translat...UTF-8&oe=UTF-8

Noah Yuan-Vogel November 8th, 2007 01:09 AM

maybe, but for what? geode cpus are very slow.

Alex Stewart November 20th, 2007 05:23 PM

So I just finished reflowing the camera chip on to my heard board PCB
http://goosetech.homelinux.com/photo.php?photoid=6

Looks good! I wont be able to get around to coding up the interface for a while (exam week doth approach)

But hopefully over Christmas we'll see the first pictures out of this puppy!

Also, for processors, Im looking at the BF537

Its a 500MHz Analog devices DSP with two built in MAC's which means Ill have a myriad of avenues for encoding.


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