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-   (MPG4) Sanyo Xacti (all models) (https://www.dvinfo.net/forum/mpg4-sanyo-xacti-all-models/)
-   -   Sanyo HD1 footage! (https://www.dvinfo.net/forum/mpg4-sanyo-xacti-all-models/58228-sanyo-hd1-footage.html)

Chris Wells April 2nd, 2006 03:46 AM

A couple other notes...

When I refer to blurr as an explination to your problems focusing, it's because you don't have enough, not because you have too much. Your eyes are having to adjust to a rapidly moving scene and the images contain enough change that your eyes actually see distinct pictures. This, at 30fps, makes it hard to focus.

With blurr, your brain processes what it gets differently, and you perceive more fluid motion. The reason 60fps seems clear is that the change between frames is lessened.

Also, this is a great solid-state device, but seriously, if you are uncomfortable putting out $2-$3G for a TV, don't start launching a grand up in a model rocket. If the rapid acceleration doesn't blow your OLED, the impact from the chute charge likely will. And since there isn't any viewfinder, blowing the display is a critical issue.

Wayne Morellini April 2nd, 2006 07:12 AM

Quote:

Originally Posted by Marc Louis
as you can notice the image is not sharp (at least with windows media player)....with VLC player it's ok

I've accidentally got the wrong month and seen this. Media Player Codec has a "feature" that blurs the footage to hide macro blocking edges etc, I imagine (like h264). I think it is turned on as standard, find it and turn it off. There are also a few rendering options, I forget which, but I switched one, and it got rid of the over saturation and got a more natural toning.

Wayne Morellini April 2nd, 2006 07:15 AM

Chris T,

I think people are comparing to HDV cameras (starting at around $1300) which blow this away, but not for size. The new HC3, is close to pocketable, but again, I think this is much smaller.

For DVD, and SD, I think it is probably pretty good, and compared to many of those wireless cams. I think people have certain expectations for HD. Try getting an half an eyeful of a screen (it looks like a full eyeful, because you don't take notice of the peripheral vision) this is about the max you would expect from HD in a good Imax theatre, on a 1280 wide full screen mode and the problems become more obvious. But for what you want, no problems. You might try to check out the video latitude and what happens to the codec when it vibrates, that is probably of more concern for rocketry (though different ND/s might help depending on the day).


Thanks

Wayne.

Chris Taylor April 2nd, 2006 08:32 AM

Thanks much for the replies so far greatly appreciated !

SO far my only concern is the motion issue as thats the only thing my current camcorders dont have much of a problem with.

as for the price tag and risking it. Here is the problem. I dont see any BENIFIT gained by me between a $500 camcorder and a $2000 camcorder

and I definately dont see any advantage in a $2500 TV when a 36" Normal TV has MORE physical area and is under $1000

The ideal of recording my OWN HD content lessons this a little but not enough to justify a $2500 TV :-)

The LCD is the least of my issues as far as G-Loads go unless it had to be left sticking out in the breeze :-)

I would also heavily pad a $600 camcorder. but I am thinking the resolution is so great that it might be WORTH the risk for if I succeed the resulting video will be nothing short of spectacular.

I have a set of very nice miniature mic's with a preamp and bass cutoff. I plan to mount this in there and mount the mics on the end of a set of carbon rods to get FULL stereo seperation and effect !

I am literally drooling in anticipation of what this thing could do !

as for conditions and ISO - I dont care any settings any conditions. set it for full auto and lock focus to infinity. thats it. see how well the camera can do things on its own and that should give me a "baseline" of what I can expect from it. ie any "glaring" issues that would make it unusable to me should appear and make themselves known.

I especially want to see the full auto results in a restaurent and fast moving action shots.

So far all the videos posted have been "very" controlled and "static"

Here are some of the kinds of things I shoot (stills)

http://www.naramlive.com/

Chris Taylor
http://www.nerys.com/

Chris Taylor April 2nd, 2006 11:22 AM

One more test if someone is willing.

start up the camera and start recording (anything)

now do one of 2 things. yank the SD card or yank the battery (without stopping the recording)

is the "halted" recording salvageable ? IE can you extract the video even though it was not terminated properly ?

If I drop it or bump it hard enough to jar the SD or BATT loose I want to know if I will loose the video I was in the process or recording.

if you can't yank the battery or sd while running try running on AC with no battery inside and then interupt the AC power.

Chris Taylor
http://www.nerys.com/

Chris Taylor April 4th, 2006 01:09 PM

Well I bought one. Should have it today if I am lucky tommorrow if I am not lucky

once I get it I will shoot some vids and see what happens and upload some samples

Chris Taylor
http://www.nerys.com/

Chris Taylor April 4th, 2006 06:25 PM

Ok got it !! First impressions.

I LOVE the weight. the rocket will not. I am having second thoughts on putting this inside a rocket unless I am well enough off at the time to purchase a second one.

Ok outdoors so far as expected (autofocus does do an awful lot of hunting under certain conditions I think I can fix that by changing it to spot focus)

Indoors. Kitchen stuff "Casual Lighting" as expected very low noise (RELATIVE to what I am used too !!) but "low light" is not as good as I had hoped. I dont think it will work at say a birthday party in a restaurent without auxilary lighting. looks like I'm gonna have to build a bracket for it for some lighting.

No test vids yet I was just screwing around with it. Tommorrow I will shoot some test vids and get them uploaded.

Some other notes. I "interupted" the camera by yanking the battery while it was recording and it worked just fine ! Video plays fine right up to the batt yank so I know if the SD card or Batty jiggles or pops under load I will at least be able to get the video up to that moment.

Pictures are not bad the 1.2m while video taping works well enough and could be usefull but not overly so (now if I could capture 5mp without interuption that would impress me)

quality is decent but not enough to replace my casio z57 pocket cam.

Anti Shake. well I have to say it works and works surprisingly well with some caveats

first I understand now exactly how it works why it works and why in the wrong situations it will make your video WORSE

OK follow along here I will try to explain.

take a rectangular shape. now place another rectangle on top of it but 5% smaller.

you now have a BORDER around the smaller rectangle call this your "shake zone" you can wiggle that puppy any way you wand and so long as you dont allow the edges of the two rec's to touch your fine.

Here is the problem what happens when they touch and then some. well lets say this gives me a 1/2" latitude (number from my butt just for discussions sake)

so if I move 1/2" in any direction nothing changes in the camera but what happens if I move 1" past the border limit ?

well now here is where it makes your video worse because for thwe first half in NOTHING changes but when you jerk that extra inche instead of the video moving 1.5" it JERKS .5 inches as the anti shake resets when you exceeded its limits and then finishes the move

this makes the video seem more "jerky"

now for what this is designed to do. your holding the camera steady trying to ficus on a non moving object "perfect" as long as you stay within the limits. this is however nearly impossible with a single hand. I have a very steady hand can shoot 1/4 and even 1/2 seconds exposures steady and have managed over 1sec exposures freehanded.

so you need to use two hands relax breath and use your bodies own built in anti shake to help the camera.

the anti shake will also be EXCELLENT for tripod shooting. yes I said tripod shooting because it will eliminate tiny "bumps" eliminate "vibrations" from say a running car you are using as a steady spot mount or "wind" vibration that could make the camera buzz (vibrate)

but thats about all its good for. It would be neat to use the ENTIRE sensor patch for video buffer space (unless they already are ?) to give more latitude but what happens when you WANT it to shift ?

the little dongle will come in handle to allow me to use external battery packs. its 5v though so none of my standard packs will work. any idea what ths things tolerances are ? ie how far above or below can I go from 5 and have it still work?)

More later as I play more

Chris Taylor
http://www.nerys.com/

Euisung Lee April 5th, 2006 02:35 AM

Hello
New member first posting here.
I found this place thanks to xacti hd1. I have a great interest in this 'toy' cam cuz I can easily see this one replacing my sony pc120.

Yet the word 'HD' has such a strong aroma I keep wondering the best possible image quality you can get out of this. Reading through this long thread, the most outstanding issue is that jagged edge on the diagonal lines. On my mac it is happening on any lines running NW to SE (\) direction. It is happening in all footage posted here, with some varying degree. I think this could be a bug, but possibly more the limitation of this model. Some sort of compromise they had make to use one CCD for high res image and movie acquisition.

It seems that soft or vividsoft setting suppress the jaggedness the best, and the baby footage was probably shot with soft setting.

Anyhow, is anybody following up on this issue? Could Sanyo be working on it? I think this jagged \s are the number one reason for the quality degradation, much more so than the mpeg compression.

Thanks

Mark MacLean April 5th, 2006 04:29 AM

Quote:

Originally Posted by Joseph Aurili

Joseph, I assume that this is the user manual, but I am having a hard time downloading it. Is it still on the server?

Wayne Morellini April 5th, 2006 06:10 AM

Quote:

Originally Posted by Chris Taylor
but "low light" is not as good as I had hoped. I dont think it will work at say a birthday party in a restaurent without auxilary lighting. looks like I'm gonna have to build a bracket for it for some lighting.

There is another way you could get a few more stops, use a condenser 35mm SLR adaptor. What happens is that you get a suitable condenser (however you work that out) in an adaptor for the lens. The condenser will give you the same field of view, and from what I understand the same depth of field, plus hopefully, much more light from the increased aperture of the new lens (if better aperture size). Now get a good ND set (outside should over saturate easily with out them, maybe the ND will increase latitude).

Joseph Aurili April 5th, 2006 07:05 AM

That is the user manual for the software, not the main manual. I just clicked on it and it laoded up fine for me.

Chris Taylor April 5th, 2006 07:05 AM

shot a couple of vids really quick (uploading now)

http://www.nerys.com/sanyo

they are big so I will only leave them for a day or so few days tops. as I get more I will delete the old and replace with the new ones. CANT WAIT to get to the flying field and shoot some rockets !

I figure at least 1 hours before its done. man what a difference to me. I am used to a megabyte a minute and now I am shooting a little over a megabyte a second :-)

I like that I can whack the toggle up and "lock" the autofocus so once its where I want it I lock it so any potential hunting it eliminated.

so far its doing a pretty darned impressive job. (I am comparing to my mpeg10w and consumer level dv camcorders)

I am going to have to build a head mount for this and a light bracket for low light shooting.

This thing is going to be fun. anyone who downloads my vids. any idea where the crackling sound is coming from in the audio ? it also does something weird to my voice when I talk from behind the camera. I have yet to connect an external mic.

Chris Taylor
http://www.nerys.com/

Wayne Morellini April 5th, 2006 12:29 PM

HD DVD players/software.
 
I mentioned HD codec DVD players somewhere, so relatives can watch it without a computer. I have also found some HD encoding software better than H264 or WMP that you might be interested in.

http://www.theregister.co.uk/2003/11..._killer_video/
http://www.reghardware.co.uk/2005/11...me_production/


The down loadable stuff is linked to these pages (these are the people that did the codec they use in Ogg, their VP3.2 codec, they are now upto version VP7):

http://www.on2.com/technology/vp7/
http://www.on2.com/video_samples/vp7-samples/
http://www.on2.com/company/

You notice that the PSNR maxes out around 36db, you get max compression on your upper 6 bits (36db, 48db=8bits) because there is less noise. This might explain why people are saying the bottom right black tiles are all black in the test pattern test of the HD1, it might be dropping them to increase compressibility. Can anybody confirm this?

Bo Lorentzen April 6th, 2006 12:38 PM

Restaurant shot
 
Somebody kept mentioning "restaurant shots"

so I shot one last night.. snow storm, but there is a picture. (smile)

http://www.bophoto.com/HDV/video/SAN...pan-400iso.MP4

Say... can somebody tell me where to get this "35mm lens condenser" ????


Bo

www.bophoto.com/panos

Jacky Yew April 6th, 2006 01:03 PM

Quote:

Originally Posted by Wayne Morellini
This might explain why people are saying the bottom right black tiles are all black in the test pattern test of the HD1, it might be dropping them to increase compressibility. Can anybody confirm this?

There are 10% highlight and shadow details are being clipped with normal YUV -> RGB conversion. If you have VLC player, try to press ctrl-g to access "Extended GUI" and reduce contrast during playback to reveal hidden details.

Chris Taylor April 6th, 2006 04:32 PM

Wow not bad !! yeah its noisy but its emintly usable video even with the noise. on my MPEG10w the noise is soo bad that the video is all but useless in that kind of light assuming I would see anything at all !!

I am definately going to build a module of wide angle diffused LED's to improve night time shooting at close range (restaurant shooting range)

Even moderate indoor lighting is enough to make shooting very pleasurable.

I an uploading some footage I shot at denny's this afternoon. it was pretty bright indoors what I would call medium lighting. it did uite nicely though it did have issues with focusing sometimes not too badly though. whats nice is the display resolution is high enough that I can SEE in real time when its having even small focusing issues and can adjust. its much better since I set it to center focus.

The videos will be online soon. http://www.nerys.com/sanyo

Chris Taylor
http://www.nerys.com/

Euisung Lee April 6th, 2006 08:34 PM

HD1 bug?
 
An article on jagged \ line issue.

http://www.akihabaranews.com/en/news...+to+a+bug.html

Hope Sanyo fix this issue sooner than later. I'll buy one as soon as they do!

Chris Taylor April 6th, 2006 09:20 PM

I am not so concerned over will they fix it so much as can they fix it for those of us who already bought one :-)

its not a HUGE annoyance to me but it would definately be nice for it to be fixed as it is visibly obvious.

Chris Taylor
http://www.nerys.com/

Chris Taylor April 6th, 2006 09:23 PM

So some questions. Does anyone know if the EDITING function done IN the camera recompesses it or not ?

it does not look like it does but I dont know for certain. I wish the editing was easier right now I have to PLAY till I get to the start of the clip I want and edit delete first part and then play to the second part where I want my clip to end and then edit delete second half.

this works but its slow and arduous. a quazy time line or a HALF playback speed option would be nice where I pick both my start and end point and it would then let me "preview" this and even "adjust it" and then create the new file.

that would be nice. Especially since I dont know of any lossless way to do this on the computer. Since the camera can do it it seems logical software should be able to as well (I can use TMPGENC to do this with mpeg1 and 2 files) is there a way to do this with mpeg4 files ?

Chris Taylor
http://www.nerys.com/

Euisung Lee April 6th, 2006 11:01 PM

Quote:

Originally Posted by Chris Taylor
So some questions. Does anyone know if the EDITING function done IN the camera recompesses it or not ?

Mpeg4 is an interframe compression so by its nature whenever you cut them it has to reconstruct GOP, ending up recompressing it. But it won't recompress the entire clip, just the adjacent GOPs.

Chris Taylor April 6th, 2006 11:10 PM

Thats fine ! I just have to make sure what I want is not in these gops any idea how big they are time wise ? ie what is the smallest time roughly that I should pad clips with to prevent recompression ?

ALSO what software on the PC will do this ? ie only recompress what it must when I cut up clips ?

Chris Taylor
http://www.nerys.com/

Wayne Morellini April 6th, 2006 11:56 PM

Quote:

Originally Posted by Jacky Yew
There are 10% highlight and shadow details are being clipped with normal YUV -> RGB conversion. If you have VLC player, try to press ctrl-g to access "Extended GUI" and reduce contrast during playback to reveal hidden details.

Thanks, that is good news, that it is not trying to do cheap compression tricks.

I wish Ambarella would hurry up, no information for the March release they wanted. Probably some production delay.

Wayne Morellini April 7th, 2006 12:20 AM

New In camera Edting idea
 
Quote:

Originally Posted by Chris Taylor
So some questions. Does anyone know if the EDITING function done IN the camera re-compresses it or not ?

I wish they would add better in editing function in camera. As you know, many computers lack the power to edit H264, Mpeg4, in realtime. What use is it going to be for consumers, if it takes so long to edit on their PC's. They could write an application that allows a pc to control in camera editing, and display live views USBed from the camera, in the editing window. This could work on any PC that can just display H264/Mpeg4, if there was enough power in camera, to change and transmit the view in an intermediary format, then most computers could be used to control the program. This would be a great boon to average users buying it, because it would discourage others from telling them that it is too slow to edit.

David Kennett April 7th, 2006 06:34 AM

Wayne,

I think you've hit on a GREAT idea!

I see most things done in the computer - files stored on the HD, etc.

But using the hardware encoders and decoders in the camera would REALLY help things along!

This would take cooperation between camera makers and editing software makers. Could the codecs in the camera be accessed by the software just like any other software codec? It boggles the mind!

Bo Lorentzen April 7th, 2006 08:00 AM

Hardware Encoder
 
The issue with coporation between camera and software manufactures might be dificult. ;-)

Maybe an alternative might be somebody manufacturing a firewire device which is a straight stand alone encoder setup for being controlled by software from the computer.? Plug it in like a dongle and start editing.


Bo

www.bophoto.com/panos

David Kennett April 7th, 2006 08:10 AM

Chris,

I too wonder about GOP structure in the HD1. I have software that allows me to see GOP structure for MPEG2, but nothing for MPEG4. Conversion program from Nero defaults to GOP range from 5 to 300 frames. Apparently the software can dynamically change the structure for greatest efficiency.

I did notice that a test edit I made in the camera did not seem to be too precise. I suppose that the ability to cut a clip in-camera might be most valuable to remove most of a long clip, on vacation for example, to save space. I know I have shot long scenes waiting for a whale to emerge from the water, or a big chunk of ice to drop from a glacier. It's a shame they did not include the feature whereby you start shooting 5 seconds BEFORE you press the start button. It's pretty easy to do with memory card.

David Kennett April 7th, 2006 08:20 AM

I envision a continuing progression of codecs as technology improves. The beauty of using the in-camera codecs is that it's exactly what's needed for YOUR camera.

Chris Taylor April 7th, 2006 12:54 PM

Actually how much memory would the camera need to have internally to allow that (precatch) and how much processing power since it would have to be a "running" softspace

lets say you wants 5sec that would entail at least 8+mb of very high speed space so it could dynamically write to and erase from this space and then also enough space to act as a BUFFER since once you record it has now 2 jobs.

Record from this second onward retain the last fix seconds DUMP those 5 seconds to the SD card while also dumping the real time recording once you pressed the button and also MERGE the two files seamlessly.

I imagine that is why they did not do it. ie it would probably take a ton of horsepower to do this in hardware on the camera itself.

and if you gonna buffer might as well buffer more I would love 10-15 seconds.

Chris Taylor
http://www.nerys.com/

Euisung Lee April 7th, 2006 02:51 PM

I wonder about the possibility of using GPUs for editing mpeg stream. GPUs these days from ATI or nVidia should have enough horsepower to handle mpeg in realtime. It's just that there's no software that takes advantage of it. Now mpeg2 editing is becoming more popular with the rise of HDV, something must be in the works. It's gotta be.. I hope :)

For now, on the mac, I could edit HD1 footages I downloaded from here in iMovie HD with ease. Granted it's not in native mpeg4 format but converted to Apple Intermediate Codec, but the fact that I could edit HD size clips on my 3 yr old laptop is a delight. Footages looks 'better' in iMovie than in Quicktime player because 1.25 G4 processor was having tough time decoding mpeg4 in realtime yeilding lots of blocky pixellation.

I hope cameras like HD1 or sony's HC1 and HC3 could bring HD content creation to the mass much faster than expected. Sanyo has potential be the star of that revolution. I hope they hurry and develop the next gen product sooner than later.

Euisung Lee April 7th, 2006 02:51 PM

oops same post went up twice. editing the second one...

David Kennett April 7th, 2006 02:58 PM

Chris,

I think it could be done more simply than that. I have a Comcast DVR box that constantly buffers TWO tuners to disk. In SD it buffers close to an hour, but in HD it's only about 15 min. on each tuner. If sometime after a program starts, I decide to record it, the buffered stuff is instantly converted to recorded program. It might lead to some fragmentation, but it apparently works.

Steven Mingam April 7th, 2006 03:35 PM

Quote:

Originally Posted by David Kennett
But using the hardware encoders and decoders in the camera would REALLY help things along!

not it wouldn't really help, because of bandwidth constraint over USB for uncompressed footage in high resolution... You need 30Mb/s sustained for 1280x720 so usb 2.0 can handle that but not more.

Quote:

Originally Posted by Euisung Lee
I wonder about the possibility of using GPUs for editing mpeg stream. GPUs these days from ATI or nVidia should have enough horsepower to handle mpeg in realtime. It's just that there's no software that takes advantage of it.

The problem is that the actual bus used for graphics transfert aren't designed to _retrieve_ data from GPU. AGP is almost unidirectionnal and PCI-Express, while it should have ameliorated things, didn't do that much.
(not mentionning that gpu aren't that fast for some operations you find in typical mpeg application).

Spending time optimizing things for the cpu is a better choice, imho. There is some freaky fast H.264 decoder (CoreAVC) out there that can handle 1080p footage with my Athlon 1600mhz...

Btw, i'll have a little surprise for HD1 owners tomorrow... it's called MP42AVIEdit ;)

Chris Taylor April 7th, 2006 05:12 PM

Hey david some issues

first most DVR's use mpeg2 ! (the newest DISH box I believe will use mpeg4)

Second these things are basically full fledged computers. not the tiny little thing your holding in your hands :-)

BIG difference.

The problem is not can it be done but can something this small do it and still be affordable. Remember it has to work in FASTER than real time since it has to manage the buffer AND work the new incoming stream flawlessly. if there is a blip in your recording of lost its no big deal if its a blip in your home video and that blip COVERS exactly what the buffer was supposed to capture .....

thats gonna take a rather larger buffer and a rather effecient and powerful engine to "process" all that data. over 1mb a second is nothing to scoff at.

I guess one way to measure gop is to see how small a clip it will let us cut up ?? Hang on I will try it.

Ok I did a roughly 2 second clip and tried to cut it in half. it seems to have worked fine. so it must be smaller than 30 frames right ?

I have a bunch of clips I am going to upload when I get home tonight I will upload this test clip as well

Chris Taylor
http://www.nerys.com/

Chris Taylor April 7th, 2006 06:00 PM

What would make me really happy as an HD1 owner ?

2 things

1- Someone to compile a PERFECT source of exactly the codecs we need

2- A VERY simple VERY fast as close to lossless tool as possible with a SINGLE purpose. Allow me to chop up videos from my HD1

Join - Seperate and MOST importantly allow me to SPECIFY visually a start and end point and cut that out as a NEW clip with minimal recompressing none if possible and do this FAST.

THAT would just make my day.

As for #1 here is my issue. my desktop - reads perfectly. no problem playing no problem converting to divx with dr divx and no problem sicking TMPGENC on it to make DVD's out of them.

I tried it on my laptop and NOTHING but trouble. DrDivx gives me a GREY screen resultant file with audio (in preview it sees it just fine)

TMPGENC wont TOUCH them says file not supported. Clearly this is a codec issue (I tried every damned codec I could find) because TMPGENC at home see and interacts with these files JUST fine !!

I am thinking its time to refresh the laptop hopefully I can install the same stuff that I installed on the PC but I am not CERTAIN as to what I did different on the PC verse the Laptop (its a very powerful laptop more powerful than my desktop even so thats not it)

So if someone could do those 2 things I would be in heaven. I am REALLY liking this camera. If I can satisfactorily protect the camera (working on that right now) I am going to strap it to an RC car and see how that goes. its not a great car but it can do 18mph (well maybe not with this camera on its back for as small as it is its a heavy camera)

IF and ONLY IF I have enough money to buy another HD1 by august. If that happens I am going to put this camera in a Rocket. if it was half as heavy as it is I would not be so worried but as heavy as this camera is I am not confident I can pack it well enough to survive a fall from 5000+ feet. It will probabl go terminal before hitting the ground but terminal for this thing it likely over 200mph :-)

I figure I will need at least 12 inches of Foam Rubber padding in all directions to sufficiently protect it. I am also working on a rig to EJECT the camera from the rocket with its own attached parachute in case something goes horribly wrong. that will at least give me 3 chances to bail. Motor Ejection - Electronic Ejection and Emergency Camera Ejection. that should bring the odds of a good chute up considerable. at that rate I could get away with 3-6 inches of foam. The Trick will be protecting the most prone to damage part ie the lens since it has to stick outside the rocket :-) if I add too much foam I will trash the aerodynamics which will require more power which increases cost and risk. (its gonna take a hell of a motor to get this camera to 5k and my ultimate goal of 10k)

Chris Taylor
http://www.nerys.com/

Wayne Morellini April 8th, 2006 08:16 AM

Quote:

Originally Posted by Chris Taylor
Actually how much memory would the camera need to have internally to allow that (precatch) and how much processing power since it would have to be a "running" softspace

It probably will be better to use in camera memory then SD card, because rewriting constantly to SD can damage the memory (though that might not be a problem now).

The compromise for this camera would be to continually compress and save to memory. This might consume more power, but you get many times more in the buffer. So 5 seconds, you could have 30 seconds or more.

Actually, if you treated the whole card as one big variable buffer then you could have many minutes, and avoid to many rewrites. Perfect for news people, they could be able to afford to throw away the odd wasted card every now and then.

David Kennett April 8th, 2006 09:11 AM

Chris,

I know there is a wide latitude in GOP length in MPEG 2, and their appears to be an even wider latitude in MPEG4 - apparently as long as 300 frames. Determining how precisely you can edit would not necessarily tell you what the normal in-camera GOP is. It is entirely possible to have an I-frame followed immediately by another I-frame. As was mentioned earlier, the GOPs are re-constructed around the edit point, without disturbing the program as a whole. Each GOP has header information detailing the construction of that GOP. That's how frame accurate edits can be made in MPEG.

If you have TMPEG Author, you can see the GOP structure. Look at it around some edits. Of course that only works for MPEG2.

Wayne Morellini April 8th, 2006 09:20 AM

Quote:

Originally Posted by Bo Lorentzen
The issue with coporation between camera and software manufactures might be difficult. ;-)

Actually, I envision that the manufacturer themselves could supply a basic editing package with the camera that used this, even using somebody else's software. Basically, it is an extension of the in camera editing capability (hopefully filled out to all the essential stuff pro/sumers need). And provide a API/plug-in for NLE editing developers to use. It is really a on computer GUI interface to the in camera editing capabilities.


Steve,

The bus bandwidth is not a problem, all that the computer gets is display data, compressed or not, and the results codes (error codes). The camera can also pass back the rendered footage, and receive new footage. For 720p cameras, passing uncompressed is not too much a problem for USB2, though if your machine cannot handle mpeg4 decoding, it might also have trouble with a full USB2 data rate. For 1080/4(1440, got to call it something) I think it might fit (haven't calculated it). For true 1080 though, then you will be pushing, but lossless compression might help (If manufacturers set up cameras to support it). (I realise that most simple lossless solutions do around/or less, than 2:1, but we are talking about footage that has already loss a lot from Mpeg4, so hopefully it will compress even more.



We did a look into GPU, and the latest do 80 Gflop. or so, which is like an 8 core PC cpu. Programming is a problem, when they get used to it we might see a lot more. If people program it wrong, they bust all their performance, it has to be managed it's own way. We did some looking at it in the Digital Cinema stuff, and even the AGP back channel was more than fast enough. With PCI Express, we expect extra help. But, in the end, as much that can be done should be done on the cards, and the results passed back.

Direct X is moving towards a GPU that is much like a CPU, and Direct X 10 might deliver a lot more. Xbox360 is using more advanced direct x features, and I don't know how much of the 700+Glop (I can't remember how high it goes) will be available for processing enhancement. But Graphics manufacturers are enhancing their chip with more and more encoding/decoding features. I made a few posts on GPU enhancement for H264 in the news and alternative imaging forums. I spotted something very interesting in the diagrams, it was in an ATI chip, and seemed to be meaning, to take in analogue, or mpeg2 (not sure) and "transcode" it to h264.

For everybody here, the problem is that it is still far better to do it in camera instead (H264 will tax the CPU more). Some GPU's have the processing power, and all the features needed to get the max performance. But many are slow in places, and have features "emulated" by software routines, and don't deliver the goods. Many integrated graphics chips, and laptops, suffer from this problem. Also a number of the older/cheaper graphic cards also suffer more. To be certain you will have to see what the application that is using GPU acceleration suggests, as good choices for graphics.


Seriously, I think it is much better for camera manufacturers to explore this option, particularly in the next few years. It will stop people from being deterred by the though of buying expensive new editing hardware, just to get the most from cameras with new codecs.

Wayne Morellini April 8th, 2006 09:31 AM

A bit off subject:
Chris, did that guy in England get his amateur rocket into space a few years back?

Steven Mingam April 8th, 2006 09:35 AM

Quote:

Originally Posted by David Kennett
I know there is a wide latitude in GOP length in MPEG 2, and their appears to be an even wider latitude in MPEG4 - apparently as long as 300 frames.

In fact, it doesn't matter here, because the HD1 use a fixed GOP too. An I-frame by second. So you have 1 I-frame followed by 29 P-frame.


@wayne : what you're talking about is just what you read around, and it's all PR talk and so one. Reality is MUCH MORE different...

Wayne Morellini April 8th, 2006 12:49 PM

I know. I also know that most people are just not good enough to milk a system for performance or efficiency, and then they whine about it, it's the systems fault is the usual whine, usually because they can't figure it out, then get the gullible to believe them. I've been around computing for nearly three decades, and it happens. Then after people with a real brain on their head figure it out, they find out that they could get many times more. I have come across, cynical, experts, out there, they seem to have a common problem, of turning out wrong, worth being skeptical of. Old story, stay tuned (and I am not saying that they will get everything GPU marketing promises, but most likely a lot more than the critics expect)!

I came across a thread tonight (to many threads) that was talking about a number of applications using GPU acceleration. It is not perfect. 80 Gflop peak sounds about right, it is not that crash hot. Not that you will get anywhere near it in most cases, but that is why it is called an accelerator, and not a encoder etc, but then you don't need too many Gflop to speed up encoding. I still don't think there is many GPUs that can actually deliver anywhere near 80Gflop, previous to 80Gflop being reached, performance was not anywhere near as good. So, most of this stuff is still expensive, and most systems out there won't hack it. And the stuff I quoted, is upcoming technology, which you can't judge on the basis of the results of previous/unoptimised technologies.

So, my head is screwed on straight, and what I say about using the custom specific in camera editing/encoding technology as a better solution then GPU still stands.

Now it is after 4am and I have to go to bed to clear my head.


Thanks

Wayne.


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