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Higher frames rates than 60 FPS possible

Higher frames rates than 60 FPS possible

Hi,

is it theoretically possible to achieve higher frame rates than 60 FPS to get better slow motion and if so, is any work being done in that direction?

Sorry if this has been asked before but search in the thread persistently gives me errors.

Cheers,

Robert
 
Kholi said:
Nice, Adam Baldwin. Couldn't tell from the small size.

Another question: The VGA 4:3 mode, it's of course locked to a smaller size and framerate. Being that it's only VGA, do you know what portion of the sensor it's using? Is it the actual full height of the sensor or is it a cropped mode? Is it possible to increase the recording size for a 4:3 image and the bitrate? For those of us who would shoot Anamorphic.

My camera isn't with me so I really can't test, and I think a more technical view into it would be more beneficial than unscientific glances.
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pretty sure it's the full height of the sensor, from what i remember the VGA mode's FOV was the same as the 4:3 still mode when i checked.. i want the option you're describing soo bad.
 
smkeenan said:
I know this request would more be a long term thing, but it would be cool if GH1 could be internally programmed to act as intervalometer allowing us to take time lapse without the need for external remote.
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There is already an experimental MPEG varicam patch. For normal use it exhibits heavy line skipping (hence experimental status), but for time lapse work it should be fine. Together with very high bitrates achievable in MPEG mode all the elements seem to be largely in place if you are working with sub-second intervals.
Another similar request would be for taking bracketed photos for HDR photography, the camera already has a mode that does this, but in my experience it is a bit limited, maybe im just using the mode incorrectly.
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My biggest problem with a built in auto-bracketing mode is that the camera waits for manual shutter release in between bracket shots. IMHO, it should just automatically take whatever amount of brackets shots are configured when shutter is released at the start of sequence in as short a period of time as possible.
 
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how do you think, is it any hope in future hack of firmware to record video in RAW mode from GH1??????
 
For the guys asking about higher fps -- there is, realistically, not a chance in hell. You have to understand that this is a still camera, using a still-camera sensor. It's having to pixel-bin or skip 90% of the pixels on the sensor, just to reduce the amount of data being read, so that it can get a 1080p frame.

What I'm saying is, the full sensor can't even do 4 fps. They read something like 1/6 of it to get 24fps, and even less of it to get 720/60p. You're not going to get 1080/60p because the hardware itself can't do it.

It's like asking a 1.3GHz computer processor to now run at 20GHz. It doesn't. It's not made to.

The only way to get higher frame rates would be to shoot at smaller frame sizes, the same as the Red does and the same as other CMOS cameras do. If you read a smaller portion of the sensor, you can read that smaller portion faster. Which is why a Red One can do 4K at 30fps, but it can do 2K at 120fps. It might be theoretically possible to read the GH1's chip at standard-def resolution at 120fps, but ... then you'd need a recording format that could store it, and that just doesn't exist in the camera. Could tester13 do it? Maybe. But if he does, it almost unquestionably will not be at HD resolution, it'd be SD or less.
 
Hi there!!!!

I´ve just donated for the "GH13 crew" cause!! :D...hehehe....30 dollar.

THANKS Tester13 and all Testers for the GREAT job!!
Keep it up!

Asier.
 
External monitoring

External monitoring

Since no one mentioned it I either missed it and it's implemented, or maybe not everyone needs it - but an option to NOT turn off external monitor via HDMI during recording would be great!
 
Barry_Green said:
You actually get about the same codec efficiency from 720/60p as you would from 720/30p, or maybe even more. Long-GoP encodes only the changes between frames. In 720/60p the frames are closer together in time, and therefore have less change between them, than 720/30p does. So if you just went to 720/30p, it might be equally hard, or even harder, on the codec than 720/60p is!
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Interesting idea.

I hope this isn't true (on average) with the GH1. Otherwise, Panasonic really humped the pooch with their "AVCHD" codec. :shocked:

I agree that there are some scenes where 60p compression might outperform 30p. But...this should be a very narrow class of scenes. Basically, you are looking at cases where:
  1. Many macroblocks are changing beyond the acceptable motionvector+residual threshold, at a rate that is too fast for 30fps, but still slow enough for 60fps to retain vectors&residuals instead of dropping to intra; or
  2. Many macroblocks are moving at a speed that puts them beyond the motion-estimation radius for 30fps, but still within the motion-estimation radius for 60fps.

If the scenes do not fall within this narrow range, 30p recording obviously has an advantage because there are half as many frames to compress & save.

If the scenes do fall within this range, 30p may or may not lose to 60p. It depends on the quality of the codec.

Bear in mind, at 30fps, the codec has TWICE as much CPU time to perform variable-size block matching and other algorithms. And these compression algorithms can become hugely more efficient when you have even a little bit more time to search for a few good matches...and then quickly apply those predictions to other blocks.

So I'll make a big suggestion here, imho:

720p30 AVCHD is the most promising path for enhancing GH1 video quality.

Why?

1) MJPEG is intraframe-only, so it can't approach AVC/h264 performance for 90% of video usage, i.e, scenes with mostly static backgrounds and slow pans. Don't get me wrong, it is nice to have a high-bitrate MJPEG option for "white water" shooting. But for most scenes, AVC @ 17Mbps will whip MJPEG @ 80Mps. Bits/Iframe wins.

2) 1080p is already scraping the floor of acceptable speed at 24fps. "Filmic" is about as good as it gets without a hardware upgrade.

3) From a GH1 hardware perspective: Some folks subscribe to the theory that Panasonic would "cripple" the GH1 firmware to keep this camera in its niche...but it makes a lot more sense for a manufacturer to limit performance by using cheaper components and engineering (e.g. lower thermal design criteria). So it is unlikely that the GH1 hardware can reliably handle much more raw data than you get from 720p60 or 1080p25. The random testing of the "hacks" so far seems to be proving this point. But it can obviously handle LESS data, with MORE time to apply compression.

I'm very interested in your comments on this, thanks.

J
 
jaydil said:
I hope this isn't true (on average) with the GH1. Otherwise, Panasonic really humped the pooch with their "AVCHD" codec. :shocked:
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Why? It's true with just about every long-GoP codec. But we already know that the GH1's AVCHD is pretty much the worst implementation of AVCHD on the market, which is why we're so amped about what Vitaliy has been able to accomplish.


720p30 AVCHD is the most promising path for enhancing GH1 video quality.
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Disagree, for many reasons... :) Not the least of which is, MJPG mode can have 4:2:2, and AVCHD just can't. Secondly, many of us aren't interested in 30p at all, we want 24 and 60. Third, the camera makes sharper images in 1080 mode, it's a shame to give that up in 720p mode.

1) MJPEG is intraframe-only, so it can't approach AVC/h264 performance for 90% of video usage, i.e, scenes with mostly static backgrounds and slow pans. Don't get me wrong, it is nice to have a high-bitrate MJPEG option for "white water" shooting. But for most scenes, AVC @ 17Mbps will whip MJPEG @ 80Mps. Bits/Iframe wins.
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Simply not true in this particular case. In general, I do agree that PROPERLY IMPLEMENTED, modest-bitrate AVCHD could be very competitive or even exceed high-bitrate MJPG. But the AVCHD chip in this camera is missing the ability to do B-frames, and that has cost it a tremendous amount of potential efficiency. The 21mbps of AVCHD in an HMC40 is comparable in robustness to an intraframe codec, but that's because it has the full toolset to work with (including native "p" compression and B frames). The GH1, by default, doesn't have either. It limps along with only I and P frames. Vitaliy has been able to add native progressive to it, but he can't add hardware processing power for B-frames where the chips don't have it. So, 40mbps or higher IPPP AVCHD vs. 80mbps MJPG, yeah, that's pretty close. But 17mbps? Doesn't compare.

2) 1080p is already scraping the floor of acceptable speed at 24fps. "Filmic" is about as good as it gets without a hardware upgrade.
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Agreed; we will not get valid 1080p any faster out of this chipset. But, fortunately, many of us don't want 30p, we want 24p, and 1080 provides more detail than 720 does.

3) From a GH1 hardware perspective: Some folks subscribe to the theory that Panasonic would "cripple" the GH1 firmware to keep this camera in its niche...but it makes a lot more sense for a manufacturer to limit performance by using cheaper components and engineering (e.g. lower thermal design criteria.
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EXACTLY!!!!!!! Bless you for saying it! I'm so tired of the silly conspiracy theories and "crippling" nonsense. It's so much easier to just point out that these products are designed to meet a certain price tag. For some reason people have no problem accepting that a $300 nettop computer won't be as fast as a $3,000 octo-core desktop tower, but the same logic applied to cameras has them screaming about "purposeful crippling for protecting the high end"...

So it's unlikely that the GH1 hardware can reliably handle much more raw data than you get from 720p60 or 1080p25. But it can obviously handle LESS data, with MORE time to apply compression.
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As far as the chip goes, I believe that's exactly correct. It cannot deliver faster than 1080/25p, or 720/60p. If you tried to get 1080/60p out of it, the best you could get would be an upscaled 720p, because the chip itself simply isn't designed to be read that fast.

Less data with more time to apply compression is a great-sounding theory. If it had a proper implementation of AVCHD I'd be right there with you. I originally subscribed to this exact same line of thinking with the HMC150; I thought that unquestionably the 720/24p would be the highest-quality mode the camera could deliver, considering that it used the exact same bandwidth for 720/24p as it did for 720/60p and 1080/24p. Funny thing about it though... the 720/60p looks just as good, and the 1080/24p doesn't have really any more compression artifacts, but has substantially higher chroma information per frame.

In my experimentation with the GH1, I believe that the future is 1080/24pN AVCHD at the highest mbps we can get. I could almost be talked into 720/24p MJPG at 4:2:2. So far I don't think 1080p MJPG is viable because of the chroma moire that gets introduced, and you can't go 4:2:2 because of the card writing speed limitations, and it's stuck at 30p anyway.

But, in the end, we're talking theory versus the opportunity to test reality. I think that the lack of B-frames puts 720/30p AVCHD at a disadvantage for ultimate quality, as compared to high-bitrate 720/30p 4:2:2 MJPG. In theory, with B-frames, it should be very competitive. In reality, ... not so much.

Vitaliy has a 720/24p AVCHD patch already. It isn't working quite right last I checked -- it's sectioning off the upper-left 1280x720 of the 1920x1080 frame, instead of scaling the whole 1920x1080 down to 1280x720. I think he said something that he could maybe get it working right. If/when he does, then we'll have a chance to compare head to head, 720p low-framrate AVCHD against 720p MJPG and get some real-world results.

In the meantime, I keep my fingers crossed that he'll keep working on the 1080p AVCHD to make it as robust as possible, and hopefully fix the I-frame pulsing issue.
 
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Barry_Green said:
In my experimentation with the GH1, I believe that the future is 1080/24pN AVCHD at the highest mbps we can get. I could almost be talked into 720/24p MJPG at 4:2:2. So far I don't think 1080p MJPG is viable because of the chroma moire that gets introduced, and you can't go 4:2:2 because of the card writing speed limitations, and it's stuck at 30p anyway.
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There is also a dark horse by the name of Live HDMI Out. It has been said that the path is long and thorny, but if we get there we can forget about lack of B frames in AVCHD or controller bottlenecks in MJPEG mode.

If may go on a little uninformed dreaming trip here say it is possible to enable 1080 HDMI out in Live View mode. In that case all of the GH1 hardware resources are dedicated to converting sensor output to HDMI stream. The task of recording that raw stream is transferred to an external encoder of your choice. We know from testing, that HDMI signal in playback mode is piped out at 1080i. If we can get that signal out in Live View mode we are golden, no?
 
I was just wondering if data storage has to be onboard. Would it be possible to make a dock that fits into the SD slot in the camera and feed it out to an SSD? And could the camera just read from the SSD like it does a card so you could get playback? This would also let you get a live feed to a monitor or anything else and you wouldn't need a framestore interface, just a little battery pack.
 
Once you start getting to that point, it's time to quit trying to shoehorn a stills camera into doing what you wish it would do, and start using a product that's designed to do that. While it's not on the market yet, the AF100 will have both HD-SDI and HDMI ports that can feed a monitor and an external recorder simultaneously.
 
Barry_Green said:
Once you start getting to that point, it's time to quit trying to shoehorn a stills camera into doing what you wish it would do, and start using a product that's designed to do that. While it's not on the market yet, the AF100 will have both HD-SDI and HDMI ports that can feed a monitor and an external recorder simultaneously.
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I figure we're already way past that point.:laugh: When you take into consideration that SD standards are pretty lax and you just about have to trust luck since some C10 cards won't deliver. My lowly Transcend's tested at 9mbps while my Sandisk Extreme III tested 7mbps. All of these are C6.

Wouldn't an SSD eliminate the data rate restrictions on a give SDHC and prevent shutdowns? Would it be that much of a technical feat?

Although your logic regarding the AF100 is impeccable, I thought this forum was all about exceeding design constraints.
 
9 megabits? or megaBytes? Because by both of those numbers, if it's megabytes per second, they both qualify as class 6.

Yes, any SSD would be capable of much higher data transfer rates. But ... does such technology even exist, to go from an SD card slot to a SATA controller?

I thought this forum was all about exceeding design constraints.
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In FIRMWARE, not in custom-manufactured hardware! :D
 
Barry_Green said:
9 megabits? or megaBytes? Because by both of those numbers, if it's megabytes per second, they both qualify as class 6.

Yes, any SSD would be capable of much higher data transfer rates. But ... does such technology even exist, to go from an SD card slot to a SATA controller?


In FIRMWARE, not in custom-manufactured hardware! :D
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Well let's get that ball rollin' dude!:dankk2: I know they're both in spec but the Transcend was trashed as a bad card in a couple of articles but they exceeded the highly rated Sandisks. As far as the technology existing, I think Sony had something like this for one of its high end video cams that allowed one to use an SD card instead of the expensive Sony card. It looks to me it would be more about cobbling up an interface rather than esoteric techno-savagery. I mean you can hook SATA controllers up to a bunch of stuff like ieee 1394 and usb so maybe even an SD card.

Check this out:

http://www.bit-tech.net/news/2008/08/12/sata-sdhc-raid-spotted/1

Its a SATA SDHC RAID so there has to be some compatibility. it could be a really compact portable unit in a little belt pack. Think it's worth a try?
 
[Still Feature Request] Increase EV Bracket Spacing

[Still Feature Request] Increase EV Bracket Spacing

I know all you guys are mostly concentrate in modifying video feature. But if you have time to add this hack to the list, I think many HDR folks will be more than happy.

As you know G series camera has a nice bracket feature of 7 shots max. but EV spacing is rather limit at 2/3 EV max. so in order to obtain 3 bracket shots with 2 EV spacing one needs to use 7 shots with 2/3 EV spacing and ignore 4 shots in the middle.

It would be nice if we can increase EV spacing to 1 or 2 EV so we can have more ideal bracket shots like 3 or 5 or 7 shots with 2 EV spacing which is most HDR photographers normally need.
 
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