Any GH2 news on the HDMI output front?

all 1080 modes the GH2 is providing are regarded as 1080i from the AJA Io. The live signal is always interlaced. If I play back a clip, that was recorded as 24p to sd card, it looks progressive because the fields are the same.

if I switch from 1080i to 1080p on the AJA side, the signal gets lost.
 
Dazza said:
I don't think the hdmi output ever passes thru the avchd encoder. Setting the camera to record just changes the sensor output values
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no, but it should make a difference if the signal comes directly from the sensor or from a avchd encoded file from the cameras sd card.
 
Ian-T said:
Nope. I never said that. Must be another Ian.

Can anyone of you name me a camera that outputs a non interlaced signal via HDMI? Anyone?
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Clever defence. It is always nice to see intelligent people around :-)

The other way round is also worthy, though. It is crippled anyhow. Or the signal via HDMI @ AF100/101 (same for F3) will only be interlaced too? ;-)
 
here is a side by side of HDMI out to AJA IO and AVCHD from sd card:
 
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According to the GH2 manual, on p.61, there are 4 options. 1 is auto (to match the TV it's hooked up to), 2 is 1080i, 3 is 720p, and 4 is 480p (if it's an NTSC, etc.).
From that, I would guess that there is no 1080p option for the HDMI feed off the GH2. The fact that your AJA loses signal when set to 1080p may confirm this.

However, keep in mind, that the 24 fps signal doesn't come over HDMI, during playback, UNLESS you set the HDMI mode to Auto (this from the manual on page 159). It states "During [24P CINEMA] and [VARIABLE MOVIE MODE] playback, please set [HDMI MODE] to [AUTO]. For settings other than [Auto], it cannot output at 24 frames/second."

So, those settings may also apply when simply recording from the camera as well. You may need to set the camera to [AUTO] in order to get 24 fps fed through the HDMI signal, which may still be 1080i, but with added pull-down.
For 2 weeks, we have waited for anyone to do this test, but there's only one test I know of, and it was contaminated with editing on a 60i timeline.

If I had a GH2 I would see if I could get a signal to my HDMI recording setup with the GH2 set to [1080i], and see if I could remove the pulldown from the recorded file (AE or Shake can do this quite easily). If the pulldown can be removed, it will automatically remove the interlacing in such a way as to preserve the original resolution of 24p. This single accomplishment would be revolutionary for such a cheap camera. But no-one has succeeded (that I can see.)

Now, if removing pulldown doesn't work, the next test I would try is setting my camera to [AUTO]. I expect, however, that this won't work because I suspect that the [AUTO] mode is looking for EDID from the "TV" it's getting ready to feed. If the AJA card isn't sending out EDID data to the camera, the camera may not put out the right cadence. From what I'm guessing here, Panasonic doesn't want to put out a 24 fps video to a device that's not able to handle it, so they're using the [AUTO] mode to prevent it from happening unless a display can actually handle this.
So, if your capture solution doesn't give out the right EDID info, you may not be able to get a 24 fps stream (with the added pull-down or not - I don't know) out of the GH2.

So, if the [AUTO] mode doesn't deliver, the next step would be to get a EDID cheat in the middle of the chain to fool the GH2 that it is "seeing" a 24 fps ready device for display. Such a device can be had on ebay for $110 at a link like this. http://cgi.ebay.com/ws/eBayISAPI.dl...02327&ssPageName=STRK:MEWAX:IT#ht_5814wt_1141

The capability to record "uncompressed" video from a chip size this big from a camera body this cheap is extra-ordinary. To be able to record a non-interlaced image, through pull-down, would be stunning.

So, without restating the obvious, getting a 24P signal, prior to it being compressed in the camera, outside where it can be captured with your codec of choice would be fantastic.
Yet, to date, no-one has conducted a test to confirm if this is possible.

Not Phillip Bloom. Not Andrew Reid. Not anyone that I can see.

Perhaps you, aemonk, will be first. Perhaps only a compositor will understand just how incredible this feature is. If it really exists.
 
Didn't realize you'd posted stuff on Vimeo while I was writing. I just checked out your last two files (GH2 24p HDMI2AJAIo and GH2 24p AVCHD2ProRes).
First, I noticed that your AVCHD2ProRes clip is the same number of frames as the HDMI2AJAIo clip. So they were both streamed from the GH2 the same - whether 60i or 24 fps or whatever. However, the HDMI2AJAIo is interlaced, so why is it the same length as the 24p AVCHD2ProRes?
I don't understand. It should be 80% shorter.
With a simple de-interlace applied to the 24p HDMI2AJAio (using Shake here) it looks identical (frame to frame) to the 24p AVCHD2ProRes clip. Which sucks. There was no pull-down added to either signal, so I couldn't remove pull-down for a clean plate. It seems that what you recorded from 24p AVCHD2ProRes was a 30p signal somehow.
What am I missing here?


Are these original capture files you're uploading, or were they brought into a timeline first and then exported?
Could you please convert your avchd file directly to ProRes (without streaming) and let us compare that to what you captured over HDMI? That would be a help for figuring out true frame-rate.
You're a big help, aemonk.

Thanks for taking the time to explore this as far as you have. Nice to have SOMEONE out there actually interested in understanding the mechanics of what's going on here with the GH2, instead of focusing on inane events or happily typing away on their favorite plugins - of all things.
 
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What's the delay like on the HDMI output? Is it pretty much instant?
Also, can it output a clean HDMI output while in preview mode?
 
I tried hooking my US GH2 up to my 5 year old Rear Pro TV via HDMI. It worked perfectly. I could record on the camera and see the icons and still see the video output on the screen with no icons. I had it on Auto mode but my TV does not accept 1080p. The output was 1080i as indicated by my TV. I will have to test it tomorrow to see what it does on a 1080p TV.

I also tried composite connections. It will not display anything over composite unless your are in playback mode. Hope this info helps.
 
It would be interesting to see if a 1080p capable TV would receive a 1080p signal from the GH2 - since it is never specifically mentioned in their user manual. If you can't, try following those instructions I wrote about earlier, and see if that helps.
If you ever do get a 1080p signal, especially with the camera just being on or even recording, then it seems that a device like the EDID Detective might be able to force the GH2 to deliver that spec when hooked up to a recording device.
The question on getting any form of 24 fps over the HDMI still remains. AEMonk's samples have me completely baffled. It seems that he was getting 60i and 30p, unless there's a step in there that he hasn't told us about.
Both the same length. One fed from the camera at presumably 1080i - but at 24 fps? The other fed from playback off the camera, but at 1080p? He didn't indicate that he'd removed pulldown on the last file.
Ha. Maybe this is the part where everyone tells me to get on Google and Wiki and so I can discover that everyone knows something I don't. So, don't hold back guys. Enlighten me LOL!
I'm pretty excited that some people are starting to seriously explore this stuff. Finally!

Jockomo - you know where I'm going with this. Some pixel peep cameras - we pixel peep keys/tracking/color-grades - you know, where all the REAL magic happens. And AVCHD, in any flavor, blows chunks. If we can get 24 fps uncompressed off this GH2 chip, it'll be explosive:Drogar-Mark-10(DBG). (Only the global shutter left to deal with.)
 
aemonk said:
all 1080 modes the GH2 is providing are regarded as 1080i from the AJA Io. The live signal is always interlaced. If I play back a clip, that was recorded as 24p to sd card, it looks progressive because the fields are the same.

if I switch from 1080i to 1080p on the AJA side, the signal gets lost.
Click to expand...

This is in line with the testing I did with my Matrox MXO2 Mini, everytime I tried to record, I would get interlaced footage, that looked worse then the AVCHD might I add. It also kept recording at 30fps, even if I set it at 1080/60i. So my tests also seem to show it's not possible to get Progressive.

Now I relatively new to this game, so there is definitely a chance I was doing something wrong, and unfortunately I've yet to learn about pulldowns and how to achieve them, so I can't really test that theory either.
 
If the camera were recording in 24 fps and sending that over HDMI 1080i, it would have to send the 24 fps cadence over a 60 field per second cadence (I can't be bothered writing 29.997 for all this stuff, so any eager beaver engineer types, lay off my simplified description here).

Let me make this simple for the purpose of clarity - I don't want to insult anyone's intelligent (you're all smarter than me anyway).
If the GH2 is shuttered at 24 fps it's like a conveyor belt delivering 24 buckets of water every second.
If the HDMI output is clocked at 60i (60 fields per second), it is sending out 60 half-bucktes of water ever second. We'll simplify it and treat the 60 half-buckets as 30 full buckets. For this explanation it's important to stay simple.

So how can a 24 fps camera send out 30 buckets of water, without any of them being empty (ie. losing sync)?

A cheesy solution would be to send out 24 buckets 1 to 1, and then keep duplicating the last Camera bucket 6 more times. No bucket goes empty, but every second you get quite a pause as 7 buckets look identical LOL.

A less cheesy way would be to dump the first four Camera buckets into the first four HDMI buckets on the other belt, and then quickly duplcate that last Camera bucket into a fifth HDMI bucket.
Send 4, copy the 4th, makes 5, so on one side we get 4 x 6 = 24 Camera Buckets and on the outgoing side we get 5 x 6 = 30 HDMI Buckets, and no bucket goes empty - we keep sync.

Problem is, the resulting conveyor belt looks a little stuttery. Every 4th and 5th frame seems to "freeze" because they're identical.

So there's another way. We simply pour the first two Camera buckets (Cbuckets) into the first two HDMI buckets (Hbuckets), then copy half of the second Cbucket into the third Hbucket. Then we take from the third Cbucket, and finish filling the third Hbucket up the rest of the way. We then empty what's left of the third Cbucket into the outgoing fourth Hbucket, and fill that up with some of the fourth Cbucket. Then we simply copy the whole of the fourth Cbucket into the fifth Hbucket that is leaving, and voila, we have four Cbuckets in and five Hbuckets out, but two of the Hbuckets are created by mixing things up from three Cbuckets, and we lose the stuttery look of the previous method.

The beauty of this system is that all the footage can be restored back to the original 4 buckets by removing pull-down - which you can find in After Effects by selecting a clip and using File>Interpret>Main.

But a quick way to check if your interlaced footage has pull-down applied is to load it into AE, and make sure that under "Fields and Pulldown" (in the Interpret menu) that Separate Fields is Off. Then advance through your clip 1 frame at a time. You should see a cadence where several frames look progressive, and then a couple of frames will be interlaced, then they'll be progressive again. (Make sure you check this where there's lots of motion, so you don't get fooled.) The interlacing is where buckets 2 through 4 are being mixed up to make 2 frames that really never were recorded that way.

If you ever find footage like this coming off the GH2 from HDMI, you're on your way! Removing pulldown will restore your footage to true 24p, since the interlacing is not eliminated by interpolation (which may please the eye, but is not true resolution) but by recombining fields to recreate the original 3rd frame, and tossing out the extra frames not needed.

Long post, but sometimes research requires clarity of purpose. If I had a camera, I'd be doing the research myself. What I don't understand is why this hasn't been the single biggest priority to explore since the GH2 was released. Especially by those who seem to make a living by posting blogs about their special insights to the video camera cosmos.

It's like claiming to be a jewelry specialist and obsessing over some garnet you just panned out of a river, when there's a bag sitting on your desk with a hand-written card on it that says
"Uncut Diamonds.
Love,
South Africa."
 
hi sandbox, thank you for your input! I will follow your suggestions!! I will take me a while to do so since I now have to do some other work. Sorry for those shitty vimeo clips, I haven't done this carefully enough. I just rushed it out of fcp last night. I Have to make sure that those various conversion steps don't change the stream (mts -> Prores ->x264 for faster upload -> vimeo). I had those clips on the same time line that's why they are equal in length. I remember that the second clip on the time line required no rendering. I probably had wrong ProRes setting for transcoding the .mts??
Here at my office I don't have the AJA Io, so I continue later the day ...
cheers alex
 
aemonk said:
hi sandbox, thank you for your input! I will follow your suggestions!! I will take me a while to do so since I now have to do some other work. Sorry for those shitty vimeo clips, I haven't done this carefully enough. I just rushed it out of fcp last night. I Have to make sure that those various conversion steps don't change the stream (mts -> Prores ->x264 for faster upload -> vimeo). I had those clips on the same time line that's why they are equal in length. I remember that the second clip on the time line required no rendering. I probably had wrong ProRes setting for transcoding the .mts??
Here at my office I don't have the AJA Io, so I continue later the day ...
cheers alex
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thanks Alex for all your efforts.
you can upload the clips as raw as possible for downloading (not Vimeo)
 
shooter_ said:
you talk, talk. But I'd like to only know... progressive via HDMI full res or not?
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wanted to say the same but thought it's a bit rude.. well it looks like 90% chance the answer is no :( it seem they put quite a heavy defense on the HDMI)
 
shooter_ said:
you talk, talk. But I'd like to only know... progressive via HDMI full res or not?
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you read, read. then you know:

"NO PROGRESSIVE HDMI OUT ON THE GH2" yet.

Maybe there is a setting, or a trick, or a work flow that gives us progressive 1080 over HDMI out. So we need some more talk, talk, than try, try, than we know for sure ...
 
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Sandbox said:
However, keep in mind, that the 24 fps signal doesn't come over HDMI, during playback, UNLESS you set the HDMI mode to Auto (this from the manual on page 159). It states "During [24P CINEMA] and [VARIABLE MOVIE MODE] playback, please set [HDMI MODE] to [AUTO]. For settings other than [Auto], it cannot output at 24 frames/second."
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HDMI was set to AUTO. Choices are

AUTO
1080i
720p
576p

AUTO don't help to get 1080p. 1080p may not exist in the HDMI/AVCHD implementation of the GH2. Or do you think AUTO gives more choices according to the EDID feedback?? Try, try ...
 
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aemonk said:
"NO PROGRESSIVE HDMI OUT ON THE GH2" yet.

Maybe there is a setting, or a trick, or a work flow that gives us progressive 1080 over HDMI out. So we need some more talk, talk, than try, try, than we know for sure ...
Click to expand...
ok give it to here! :)
 
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