Decimation
 

Juan,


can you give me the name of the main chip in the DVX? I might be able to evaluate my estimations in the first place, whether it is still the old DV25 hardware codec with fixed decimation or a new, more versatile DSP. Call it a hunch, but I wouldn´t be astonished if the DVX uses the same DSP like the 900 for instance. In the last years, LSI developing significantly surpassed manufacturing in costs. It is simply more economic to have one chip design for all purposes. From my adventures with various editing suites and gearings, chroma compression can become really frustrating especially in matching real life shots and composed elements and is highly responsible for the video look. But don´t take me wrong, it´s definitely worth a try. Thank you again for your research and share of insight.

it is an Atmel microcontroller, so it is hard to know what it does without somehow downloading the code with which it was programmed.

DSP
 

Very nice, so at least it is not the old all-in-one codec. What´s the proper name? By the way, if you happen to have a scope you might be able to scan the carrier frequencies in the Y/C stage. These should be around 13,5 MHZ for 4:4:4 and 6,75 MHZ or 3,375 MHZ for 4:2:2 or 4:1:1 respectively.

Question...
 

Ok, this is a question to everyone who is interested in this idea.

I've gotten a ~lot~ of emails from people who are interested in doing this to their DVX's, asking how much it would cost. Now the reason I am writing this, is because I am at a stage were i have to make a choice, whether i purchase a last piece of equipment for test purposes, or to actually design this to be encased in the DVX itself.

So i guess my question is, how many of you would be interested in having this installed on your DVX, and how much would you pay? The assumptions are that it provides 4:4:4 12-bit uncompressed full CCD frame resolution video at at least 24fps (progressive of course). Also, that it is that the DVX will work as normal, completely assembled, with the only changes being a ribbon cable coming out the back and hooking up to a small box mounted on the camera itself.

Note that the $25,000(+lenses) SDX900, puts out 4:2:2 with 3:1 compression and standard frame size. The setup I am describing here would provide much better quality video, the only differences being the glass and the CCD size(correct me if i'm missing anything, i know there are extra gamma settings, etc but i've never used an SDX).

Juan

Juan,

If you can produce what your saying you think is possible, then money isn't (won't be) the issue. What is at issue, is whether or not it's possible.

I would therefor suggest you provide a working prototype or at least prove your theory with an actual working design, even if using bulky parts that would never sell as a prototype.

I would further suggest to those who desire this to work so much they are entertaining some form of financial support, be very cautious. This is at this point, this is only a concept and in no way a reality.

Again, I hope this is possible for you Juan and that you succeed in you quest and develop a working model or prototype.

-Rodger

I'd say the major problem is storing all of this. Even if you can
get a RAID array to store the information that fast you would
have to carry your PC with you on your shoots? And not to
mention how to edit it, but that's a more easily solved problem.

A working prototype would definitely be the way to go. Also
to see what the difference in qaulity would be. Put the camera
on a tripod and take a framegrab of the firewire stream from
a highly detailed scene and at the same time from the 4:4:4
12 bit out as well. That way you can easily see in any paint
program what the increases are.

What camera controls will be missing with such a system?
(gain & white balance at least I'd assume)

Juan:

I encourage you to move full speed ahead. Based on what people pay for increased rez on the DVX100 and other cams via anamorphic adaptors and/or software (Magic Bullet's deartifacting etc.), I would think $1000 would be an easy starting price point for a system.

I also think that with hard disc beginning to replace tape (the new 2.5" drives from Seagate would be ideal for this), that the DV codec days are numbered.

It's the early part of this change, so your timing is just right.

Plus, some people are willing to drop $8000 on a mini35 setup or rental rates approaching 16mm film cameras which I think is too much to spend for DV footage.

I understand why one person thinks that it is closer to concept than reality, but this is not true. it is very close to being reality and this is why:

Right now I have a digital capture system which captures at more than the speed necessary to take in all the data, and I am capturing sections of frames but with very reduced precision, because of the simple problem that in order to get the full signal, I have to probe around 36 tiny pins on a surface mount chip. I only have a few surface mount probes....thus the capture system IS capturing all 36+lines, but they are hooked up to a dummy signal because i don't have the probes.

This last part i am referring to is a chip-clip that snaps on the surface mount chip allowing me to probe all 200+ pins at the same time, and thus completeing the test setup. I know that the card captures this fast, once I have the clip it's just a matter of assembling frames from the R,G,B data, which is straightforward.

The reason why I ask, is that any clip of this kind is expensive, but the smaller kind that can be put on the chip and then close the camera is even more expensive. So, this is why I ask.

I think i'm going to go all out and even if I don't end up doing anything else with it, I can leave the setup on my own DVX.

Rob: i HIGHLY doubt you need a RAID array or anything that complex to capture this data. The data rates involved are very well within the data rate supported by firewire 800. All you need is a laptop with a firewire 800 card. I've designed firewire interfaces before, and i'm positive this is not a hurdle to overcome.

Juan

Well let us do the math (correct me if something goes wrong).
We are using 12 bits per YUV channel. We have one YUV sample
per pixel which is 3 * 12 = 36 bits or 4.5 bytes per pixel. Assuming
you are going to store the laste 4 bits in a half byte and then
on with the next pixel (thus 2 pixels form 9 bytes completely),
we multiply the 4.5 by 720 and then by 480. This results in
1,555,200 bytes per frame or 1.48 MB/frame. Now assuming we
do 24 frames of that each second the datarate is 37,324,800
bytes per second or 35.59 MB/s (megabytes!). Even if you where
going to drop to 3 bytes per YUV (8 bit) this would still be 23.73
MB/s.

Which harddisk will keep up with that *sustained* without
dropping frames? Especially through a laptop!! You can't
use any internal laptop harddisks because they definitely aren't
fast enough and I think you'd be hardpressed to find any ATA
harddisk that can keep up with that sustained rate. The firewire
protocol is fast enough. Even a 400 mbit connection must just
be able to do it (although probably not due to overhead).

Let's just assume you find a SCSI harddisk or S-ATA or ATA
10,000 RPM harddisk (just out) that can keep up with this, what
about power consumption for this all? Personally I'd much rather
have the harddisk mounted directly to a camera without the
laptop.

Last time I checked there were chips and boards available with
complete ATA and firewire interfaces available, so this wouldn't
probably be that difficult to do. I'd bet you would get a way better
transfer rate out of that harddisk without going thourh a "real"
computer and the extra overhead that gives.

Now please do correct me if you think I mixed up somewhere or
am missing some points. I'm not trying to bring the project down
or anything, but I just have my "thoughts" about the actual
realworld implementation at the end. That's all.

cool thread Juan!

I wanna do this to my DV953, it would be great if you made a PDF tutorial with some pictures of the chip and probes. I would love to help out in any way I can because I was thinking about this exact type of project- because the miniDV format should be replaced by a Hard drive simply because the CCD's are out performing the tapes capabilities!

Also my home PC could handle the data rate, as it is the baddest ass mofo thing that ever existed!

Rob:

Your math looks fine, the problem comes when you start talking about hard drives, because you don't just talk about RPM and not transfer rates.

I have two laptops. They both have 5400RPM UltraATA-100 drives which can do a max of 100MB/s. This is well in excess of the 36MB/s you estimated yourself.

Furthermore, my desktop also has a 7400RPM ATA-100 drive, and it is where the capture card is mounted...it has NO PROBLEM capturing the data sustained and directly to disk.

Where am i going wrong? The data's being recorded.

A harddisk that does a max of 100 MB/s. Can you please post
a graph from a testtool which confirms this? Because I don't think
I've ever seen or read about an ATA drive that actually has a
throughput of 100 MB/s. Keep in mind that writing is even slower
than reading! ATA100 or 133 might have a theoretical limit of
100 and 133 MB/s, but the only way I see you getting that if
something is the 8 MB buffer of the drive and then you will only
be getting that at a fraction of the speed. Drive RPM usually
has a lot to do with maximum transfer speeds, which is logical,
since it can read the data faster of the discs.

See one of the latest harddisks on test at Tom's Hardware on
this page. Look especially at the graph there. That's
one of the fastests harddisk around that is doing 65 MB/s at it's
peak and falls of to 35 MB/s at the end (READ!). That's not a lot
of room for error. It gets even worse (slightly) when looking at
the write speeds. This isn't a 2.5" 5400 rpm drive either. I just
don't believe you can pull it off on a laptop harddisk, you might
on a normal fast ATA drive, but not on those small buggers.

Also take a look at the second page on that report. It lists
interface speeds as well as a bunch of common drives with their
read throughput (which again is faster than writing). I'm betting
that all of those are 7200 RPM drives.

You say you are capturing it on your harddisk now. How much
MB/s are you really writing to disk? For how long?

I am using an Adlink PCI7300A digital IO card. I can do 32 digital channels with a maximum 40MB sustained throughput. it can mantain that transfer rate until my hard disk runs out of space.

The card is interfaced directly to the PCI bus. On a firewire800 interface, the data is simply serialized instead of transferred over 32 different lines.

It works, because I wrote the program to capture it, and i've captured hundreds of megabytes of test data and i've verified that there are a negligible amount of errors with no error correction protocol as long as the probes are shielded correctly, and the computer is not doing any other bus intensive processes.

Will it work at full rate on ~any~ laptop or hardrive? Of course not. But who here expects to capture uncompressed video in real time on a slow laptop/hard disk?? I think we are all aware that this is not a concept directed at the general home-movie consumer. This is for those who want to get the best possible movie-like video for their next indie movie, or commercial, without having to pay $30,000+ to get an SDX900, or any other expensive monster.

Juan

Rob, I think we should just do it and get the ball rolling, hell by the time we actually get the bugs worked out out of the adapter Serial ATA will be up to 300mb a sec.

Im not going to let any ney-sayers get in my way, so lets work as a team and just do it!

Rob:

Benchmarks are tricky to translate to real-world use, but here's benchmarks for the Hitachi 7200 rpm drive that's in my notebook. It's widely available as a drive, including as a second dedicated and/or RAID 0 config in a number of notebook models.

It sustains plenty of write throughput to handle this as a single drive. In a notebook RAID 0, it would handle it just fine.

These are also available as upgrade drives, so you could be a kit sans notebook in single or RAID 0 to mount on a camera.

The one in my notebook is quieter and cooler than my old notebook's 4200 rmp drive. Not bad for 2.5" drive that is energy efficient (I get 4-5 hours of battery, notebook is a Thinkpad t41p).

Hello Juan,

I'm curious what HD you may be using. I've used PCI buss mastering controller technology for years in various forms, but they still require the HD to be able to sustain data throughput to hold anything close to there rated transfer rates. I could do this using SCSI or RAID but aside from that, I really don't know of any IDE type drives that would hold the nearly 40 MB per sec sustained data transfer rate necessary for this project.

This is not meant to be a poke at you BTW. A few years back I owned a small computer service company, but have since moved (literally moved also) into other areas, and have not looked back so to speak, so I really would like to know. I'll will be building a new PC shortly for video work and could make use of this info.

Thanks.

-Rodger

I see Stephen just posted while I was typing. I'll take a look at this Hitachi drive link. Still curious though. What drive would you suggest as the highest throughput currently available.

Thanks.

-Rodger

Rob:

Most any new 7200 RPM drive will sustain around 50 MB/s write:

http://www.xbitlabs.com/articles/sto...roundup_6.html

Older PCI setups and OS issues causes problems before, but new drivers on ATA5/6 and SATA setups (generally 865 and 875 Intel chipsets) are hamstrung by PCI bottleneck issues.

Rob:

The new 75 GB WD Raptor SATA is the king of the hill for desktop drives.

" I think we should just do it and get the ball rolling "

Definitely! Lets go and do this. I'm just trying to explain what
my biggest fear for such a project is, that's all.

I'm impressed by those laptop harddisks, seems like technology
is moving along. Thanks for the pointers on that.

Keep in mind though that those tests are not showing how
the curve is from beginning to end of the drive (which can greatly
vary with data throughput).

I'm still for a portable solution without a laptop, though. But lets
first see some uncompressed RAW frames at full 4:4:4 12 bits to
see if it is worth it all...

go for it
 

I hope you go all the way with this and are successful.

Would I pay $1000.00 for it if I knew it worked? Almost certainly. I bet there are a lot of dvx owners out there who would.

um I can capture uncompressed
 

guys I think that maybe some of you have not been on-top of what the latest standard disk drives can do..I put a cheap uncompressed capture card in my 2.6ghz Intell P4 system with ONE systemdrive that is a SATA and I can capture alldaylong iwth NO dropped frames...has this been the case for years? NO ...is it the case now? yes...things change and get faster all the time!

Hey anything I can do to help with the system call me in! this is the best thing since sliced bread to happen for a DV camcorder...KEEP AT IT TILL YOU GET IT DOWN! I want my dvx modified!

BTW I offer my services for any CNC work you may or may not need for this system!

I will be making radio control focus systems for the dvx shortly with CNC so let me know if you need anything! maybe a nice highquality design for a "box" that mounts on the camera?

HD 4:4:4 ??
 

juan...OMG I have a SICK idea! get your hands on a Panasonic Black Maba mx7000 it has 3 megapixels and is a 3ccd camera

http://www.supervideo.com/panason.htm

check the above link

I suppose everyone see a little clearer then then did a couple of days ago on the probability of this actually being possible - Myself included. As I have been involved with computers and this technology since 1970, I'm a bit of an 'ol dog and admittedly not a very watchful one for the past 4 or 5 years now.

As I said in my first post, I would love to see this happen and this is still true. I do still feel its a very long shot, but keep plugging away at it and once we can see actual clips I'm sure many will be willing to support and effort to complete the development necessary to manufacture this product.

If clips can be made, I could offer free hosting and enough bandwidth to move about 5 gig per day and possibly make more available as it becomes necessary.

-Rodger

Re: HD 4:4:4 ??
 

<<<-- Originally posted by Obin Olson : juan...OMG I have a SICK idea! get your hands on a Panasonic Black Maba mx7000 it has 3 megapixels and is a 3ccd camera

http://www.supervideo.com/panason.htm

check the above link -->>>

I intend to do this with my MX5000(DV953), its a 3Megapixel, 3CCD, nearly the same as a Mx7000(GS100) internally speaking

added: I will also get higher Resolution, 934x768 is the actual CCD resolution, because the cam down converts to 720x480 to fit on DV tape.

Im getting excited!

Just a note:

There is no such thing as an MX7000 - that's just the Japanese GS100 cam. Visit our Panasonic DV forum here for more details.

All posts and info on www.supervideo.com, IMHO, should be taken with the largest grain of salt available...

Plus, his pages easily rank in the HTML hall of shame and seem to get worse with time rather than better....

Agreed Stephen

john are you really going to do this?

I am not completely certain, but I beleive the raw output from the DVX's CCD's is 966x492.

At this point, it all comes down to the chip clip. if it is small enough(and i think it is) to fit on the chip with the board installed, then I can order it and have it working soon.

A word about '1.3MP' video cameras and the like...
There are two possible reasons why this idea would not work and yield HD video in such cameras...one, it is common for the manufacturers to install a large CCD to be able to read a slow frame and take a picture, but only scan a lower res at a faster rate for video.

Second, the cameras in which the entire MP CCD IS read for video(and then resized to NTSC) such as the sony TRV70, are usually 1 CCD cameras, which means that they cram 10 or 12 bit color mosaiqued into a single CCD.

Now you can do the math...say 1.3MP, 30fps, and 12-bit's...that's a lot of data. In all the cameras i researched for this experiment, the ones setup like this worked at such a high bitrate that capture to disk would be VERY hard.

This is why I picked the DVX or any other standard frame size 3CCD camera...the relatively low rez and the fact that the data is spread in parallel between 3CCD's lowers the overall clock rate to something that is workable with a hard disk.

Will keep you guys informed..i'm waiting for a response from the test clip people.

Juan

can't wait to hear what happens! keep it up, don't stop now :)

what makes you think that the image is 966x492???

what your saying is that this thing is somthing like this:
http://www.dv3productions.com/test_i...image_size.jpg

do you know if it is a clear sharp image all the way edge to edge? this will be GREAT for using steady software to smooth out shaky video and also for downconverting to SD size!

Question: what editing/capturing apparatus would one need to edit 12-bit uncompressed RAW video such as this?

Also, will a successful application of this technology on a DVX100 require that sound be recorded separately and synchronized in post?

-Craig Weinstein

Additional question: will the 24P Advanced and 30P shooting modes be preserved or will 60i be the only mode available?

<<<-- Originally posted by Obin Olson : john are you really going to do this? -->>>

yea, Obin I plan on it

I just dont really know what to do yet, aside from what Jaun has presented.

If I had more information as to which chip to jumper I would be well on my way, otherwise its a needle in a haystack.

Also what would be the prefered interface for video capture?


John

john your going to have to write code to do this? i think firewire 800 for a HD sized image would work ok?

I beleive it is 966x492, because i found the catalog for Panasonic CCD's and it's the only progressive scan CCD that could possibly be the ones in the DVX. Even though I can see the CCD/prism assembly, i can't read the model number off the CCD's because of the way CCD's are installed. Matsushita doesn't have any PS CCD's that small.

It's clearly wider, but there are usually several dummy pixels in each line, and on top of that there might be several other things. For example, the prism might be designed in such a way that the CCD needs to be wider than normal, or perhaps to compensate for the NTSC pixel aspect ratio if the CCD's have square pixels.

As far as editing it, i know for a fact that final cut pro does 10-bit 4:2:2 uncompressed...however to handle the 4:4:4 uncompressed 12-bit, i'm not sure...i think FCP has an option to import individual frames and compile them into a movie, i know Apple Shake does this. You can import in say, tiff or BMP format.

The sound can be taken directly from the DV tape. Since both recordings will be at the same frame rate, all you have to do is capture the audio from the DV tape(which records at the same time) and align it to the video. It's relatively easy to add sound once i have all of this working, but that's the way it can be done initially.

Juan

I plan to use a TI Firewire 800 chip along with all the required FIFO's, etc to interface the RGB signals to the transceiver. 800MBps is more than enough, even for the raw signal from the A/D's.

Thanks for all of the time put into this Juan. I look forward to your results.

Best,
Clayton

Oh and it should work in all modes, the interface should handle the higher bit rate of 30p/60i, although the driver will have to be programmed to handle these two additional cases....