100Mbps GH2 Low Light MJPEG 1080p Patch

how does the mjpeg 4:3 mode compare with the mjpeg 16:9 mode? I'm trying to find out if the quality in 4:3 has improved since the 1st version of the ptools for gh2. I don't have a gh2 yet or I'd test it myself.
 
Could someone tell me settings with a max. peak bitrate of 80mbit, so I can use my transcend 32gb class 10 cards. My cards got a max. writing speed of 12 Mbyte/s and that´s sometimes too slow.
 
Uwe Lansing said:

http://www.vimeo.com/27043259

The question is: Can the mjpeg patch hold a candle to the native 1024p24 avchd mode, which is indeed very good? Because the official name of the patch is "100Mbps GH2 LOW LIGHT MJPEG 1080p Patch" I´ve shot mainly lowlight footage last night. Feel free to download the mp4 file and form your own opinion...

The first scene is always 1080p24 avchd, the second one 1080p30 mjpeg. At the side-by-side comparison the left one is avchd.

Nikon 50/1.4 (lowlight)
Kit Lens 14-140 (daylight)
All night shots at f1.4, shutter 1/50 and iso 800

Currrently it seems that there is a fault with the patched audio. It captures the sound always with a gap in-between... like 2 seconds sound, 2 seconds nothing, 2 second sound.... and so on. Hopefully lpowell can fix it. And the other downside for me was that I can´t preview the files in the camera with the lpowell patch. I always get a read error. Maybe my 16gb transcend class 10 card is too slow..

Music: Solar Sailer by Daft Punk
...
Click to expand...

Any chance of getting a 1080P download of this?

Vincent
 
Thanks, Uwe, I'd be very interested to see a downloadable 1080p version of any of your AVCHD/MJPEG comparison shots.
 
Thanks Uwe, the entertainment district shots are very helpful in showing shadow detail behavior of the two codecs. Could you post them for viewing and download on your Vimeo site?
 
lpowell, I have already added them to the description of the clip and to my gh2 group on vimeo. If I´ll get the time I´m gonna shoot some stuff only with the mjpeg-patch over a few hours. Something like an endurance test. I´m curious if it can stand a longer shooting time...
 
A few questions about the 100Mbps Low Light MJPEG 1080p Patch.

Has anyone successfully reverted back to the original leaked firmware?
Anyone know the time range you can get with the 2GB limit?
When it reaches the 2GB limit and stops; does it successfully recorded everything up to that 2GB limit, (besides the very beginning)?

Thanks, I want to give it a go but have these reservations.
 
lpowell said:
GH2 cracks 100Mbps in MJPEG HD video mode @ 1920x1080p!

The 100Mbps GH2 Low Light MJPEG 1080p Patch will not work properly with previous versions of PTool. My thanks once again go to Vitaliy Kiselev, for his pioneering work on PTool, and to cbrandin for his invaluable Stream Parser tool.

The best way to insure that you have the latest PTool release is to download it directly from the following link:

Download PTool here: http://www.gh1-hack.info/ptool3d.zip

100Mbps GH2 Low Light MJPEG 1080p Patch Settings File:

This zipped INI file can be used to apply complete patch settings to firmware loaded into PTool. To use, unzip the INI file into the same folder as the PTool application. Launch PTool and load the firmware for GH2 v1.0. The settings contained in the INI file will automatically be installed in the "C" button at the bottom of the PTool main window.

Note that with the following PTool Settings File, you may at any time re-install the original Panasonic GH2 v1.0 firmware into the camera. You may also copy each type of patched or original firmware to separate SD cards, and use them to quickly switch between patches as often as you like.View attachment 37293
Click to expand...

Hi, when doing this patch - does the increment in PTool need to be changed from 1 to 10?
Is there a "prevent version compare" or "new body" settings like with the GH1?
 
Update for PTool 3.62d, with support for anamorphic MJPEG videos at up to 2160x810p!

For use with PTool v3.62d, I've prepared a choice of two INI settings files that differ in the settings for the MJPEG 30p modes:

* For use with standard lenses, the standard patch will produce two types of MJPEG 30p videos:

HD mode: 1920x1080 HD videos, with peak bitrates up to 100Mbps.
VGA mode: 960x720 iPad-compatible videos, with peak bitrates up to 30Mbps.

* For use with anamorphic lenses, the anamorphic patch supports two different squeeze ratios:

HD mode: 1920x810 videos optimized for 1.33X anamorphic adapters, with peak bitrates of 100Mbps.
VGA mode: 2160x810 videos optimized for 2X anamorphic adapters, with peak bitrates of 100Mbps.

Click the following link for the downloadable PTool INI files:

100Mbps GH2 Low Light MJPEG 1080p Patch
 
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Anyone, some dumb questions: Do most of you conform the 30fps to 29.97 in the NLE normally? I assume if I am syncing sound I should sync first (whilst at 30) then output to 29.97. Am I correct in the thought that the mbps are consistant not variable like AVCHD? If so how long do you get in the HD mode at 100Mbps with the 2G restriction? 1 minute-2minute?
 
found my own answer to the second question: JPEG
Codec ID : jpeg
Duration : 2mn 47s
Bit rate mode : Variable
Bit rate : 94.7 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 30.000 fps
Compression mode : Lossy
Bits/(Pixel*Frame) : 1.522
Stream size : 1.84 GiB (99%)
 
Obvious as it is, I still have to say that it is mind-boggling to behold the skill and tenaciousness required to produce these patches.

I wonder how it is that Panasonic would have such unused latent capabilities built into the GH2?

I find it difficult to judge the difference between the AVCD and 100 mb/s mjpg examples above. First, I would have to assume that the Vimeo re-encoding would be obscuring the original nature of the video. Second, it seems to me that I would have to see it on a big screen to compare properly. In other words, if a screen is small enough, even 3/4" video could be made to look pretty good. All that said, I would also suppose that all it takes is to view a picture in it's natural pixel format - 1920 x 1080 after which enlarging really doesn't help anything. So grappelling with that.

So i'm left wondering,

1. If one was to watch the two compared AVCHD vs mjpg videos as above in their native formats, would the mjpeg at 100 mbs clearly exhibit an improved quality? Or, as I have unconvincingly been told years before when I broached the subject on these pages, that because AVCHD is so much more efficient as an encoder, it would always fare better in an AVCHD vs mjpg shoot-out. Perhaps that response did not anticipate 100 mb/s mjpeg?

2. Those with bit rate calculators at the ready: How long could a 100 mb/s mjpeg shot run given the 2 GB limit? 20 seconds? Including audio considerations?

3. I was completely surprised to learn above somewhere that the GH1 had been patched to shoot 4:2:2 color space video. Is this true? And if so, how would a 4:2:2 GH1 shot at its best quality compare over-all quality-wise with a 100 mbs mjpg but 4:2:0 GH2 shot?

Thanks muchly,
RBG
 
1. MJPEG is essentially JPEG compression applied to individual video frames. To my eyes, its 100Mbps image quality approaches that of AVC-Intra, which is a 10-bit, 4:2:2 color codec. At this high a bitrate, I think GH2 image sensor noise and color depth become limiting factors. Unfortunately, the GH2 does not appear capable of encoding MJPEG videos in 4:2:2 color.

2. At 100Mbps, the GH2 can record MJPEG videos up to 2:45 in a single 2GB file.

3. The GH1's 4:2:2 MJPEG recordings are particularly well-suited for green-screen keying. It makes a visible difference whenever there are low-contrast image details that are primarily distinguishable by chroma rather than luma differences. Images that contain mostly high-contrast luminance details benefit less from 4:2:2 color depth than from high bitrates.
 
Good answers. Thanks, much. I'm so surprised that the "old model" GH1 can do 4:2:2" while the new GH2 cannot. I have to suspect that this is yet again an example where technological progress has been artificially suppressed in order to wring out every possible dollar (from 4:2:2 pro cameras). Similar to why, in addition to purchasing Blu-ray discs, I'm still buying DVDs in order to watch on portable players. But I digress...

So for general production shooting (ie: green screen aside), do you think the quality advantage of the 4:2:2 GH1 colour space would outweigh the imagery advantages of the high bit 4:2:0 GH2?

Man I would love to see a double-blind poll of audiences to see if such differences are detectable (even subconsciously) by audiences consumed with story and presentation. Regardless, I'm sure it is a giant big deal at places like Discovery Channel. If only on principle that technology theoretics should be worshipped. (I think back to when snowy rabbit ear TV was perfectly acceptable. Or now when different aspect ratios produce huge areas of acceptable black bars.) Still, I'll be the first to be thankful for 100 mb/s images.
 
RBG said:
So for general production shooting (ie: green screen aside), do you think the quality advantage of the 4:2:2 GH1 colour space would outweigh the imagery advantages of the high bit 4:2:0 GH2?
Click to expand...
If MJPEG's 30p frame rate is acceptable and you need a precise color key, then yes, the GH1's 4:2:2 color space can improve the quality of your post-production work. Otherwise, I'd prefer the GH2's efficient B-framed AVCHD encoder.
 
Reducing the average MJPEG bitrate to 50Mbps would require revision and retesting of most, if not all MJPEG patch settings. So it would effectively become a different patch, optimized for a 50Mbps bitrate.
 
Sounds like a lot of work. I hoped that it perhaps could be just some simple setting adjustments - without too much thought. My hopes would have been that a 50mbps patch could bring better playbacks (in-camera and on my pc) - in general better possibilities for a faster workflow in post. Besides, I´m not a big fan of too high bitrates. But I don´t have a clue whether the quality would suffer quite a lot or not...
 
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