Blackout-Powell Native 24p Patch - GH1 FTW!!!

L

Lpowell

Veteran
UPDATED to Version 2! INI files for the latest version of PTool ready for download

As you've no doubt heard, PTool 3.55d and above have liberated all previously unhackable versions of the GH1. In addition, PTool provides a variety of new patches that I've been able to incorporate into the Blackout-Powell Native 24p Patch, making it more versatile than ever.

To make use of these new features, download the latest version of PTool from the following link:

http://www.gh1-hack.info/ptool3d.zip

For version 2 of the Blackout-Powell Native 24p Patch, I've prepared a choice of two INI settings files that differ only in the settings for the MJPEG 30p modes:

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

HD mode: 1280x720 HD videos in 4:2:2 color depth, with peak bitrates up to around 60Mbps.
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: 1920x720 videos optimized for 1.5X anamorphic adapters, with peak bitrates up to around 50Mbps.
VGA mode: 1920x720 videos optimized for 2X anamorphic adapters, with peak bitrates up to around 50Mbps.

Blackout-Powell Native 24p Patch Settings Files

The zipped INI files below can be used to apply complete patch settings to firmware loaded into PTool 3.55d. To use, unzip the INI file into the same folder as the PTool application. Launch PTool and load the firmware for GH1 v1.32. The settings contained in the INI file will automatically be installed in the "B" button at the bottom of the PTool main window.

Note that with these PTool Settings files, you may at any time re-install the original Panasonic GH1 v1.32 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 Blackout-Powell Native 24p Standard Patch v2.zip

View attachment Blackout-Powell Native 24p Anamorphic Patch v2.zip

Read on for updated background information on these patches:

The New Sensation

Exactly one year ago, my (first) Panasonic GH1 arrived from Amazon. Like many high-tech prosumers, I had tried taking "home" videos on everything from Sony Hi8 Handicams, to Canon DV Camcorders, and even Apple iPhones. None of this moderately expensive gear had produced anything remotely professional-looking to my eyes, and the Firewire file capture experience made it all seem so tedious.

Nevertheless, I'd heard about DSLR HD video over the past year and wanted to see some for myself. My background in cinema surround sound and audio/video codec development led me to be fairly skeptical of how good a consumer camera like the GH1 could possibly be. But the specs looked promising on paper, I had an old stash of Canon FD lenses I was eager to play with again, and the availability of Quad-core PC's and Terabyte hard disks made the timing totally right.

My initial test shots on the GH1 in fabulous Full-HD looked immaculate on my widescreen HDTV, at least compared to my aging DVD collection. I was impressed enough with this remarkable little camera to videotape a friend's 3-piece blues band at a dingy local dive. That sobering experience was the beginning of...

The Prosumer's Complaint

The stock GH1's video quality is really not that bad, so long as it's daytime and neither you nor the subject actually moves very much. While I was experienced enough to choose the right lens and exposure for a dimly-lit nightclub, I was not prepared for the muddy low-light macroblocking the GH1 produced at its worst. I seriously considered shipping it back to Amazon for a refund.

We all know what happened next - Vitaliy hacked open the GH1 and gave us an untempered taste of what the little box could do. Well, might be able to do... with the right patch here, a subtle tweak there... and a dose of heady 100 Megabit excitement, which led inevitably to...

The Neverending Worry

Unfortunately, the impressive bitrates granted by the GH1 hack come with some unsettling hazards that can potentially ruin a crucial shot. The first hack I published, the Reliable In-Camera Playback Patch, resolved a great many of these concerns with a relatively conservative increase in video bitrate, along with 4:2:2 color depth in MJPEG mode.

One highly desirable feature I was not able to deliver was to banish the curse of interlaced pulldown that confounded the GH1's FHD videos. While the Native 24p patch Vitaliy provided would remove the interlacing from 1080p files, it was disturbingly prone to corrupting the video stream and provoking fatal lockups during recording. Month after month, innumerable dvxusers searched to no avail for the elusive secret to achieving a reliable Native 24p patch. But even when a video appeared to record without error, it might nevertheless harbor damaged or empty frames which could produce subtle glitches during playback:

blackoutvidstreamparser.jpg


Indiana Blackout and the Holy Grail

The screenshot above was produced by cbrandin's invaluable Stream Parser, and shows one of the insidious hazards of the Native 24p patch. Among the stream of red I-frames and blue P-frames are several gaps - empty frames which the AVCHD encoder failed to record. I extracted this sample from a delightful video contributed by dvxuser Blackout, who described its background here:

Creepy Denver International Airport

Sporatic frame drop-outs of this sort often go unnoticed, as they typically cause recording failures only when they become persistent. Blackout has posted numerous samples of high-quality Native 24p videos shot using a hand-crafted patch of his own. Intrigued by his enviable Native 24p track-record, I approached Blackout with the prospect of combining his well-honed PTool settings with the arcane stabilization techniques I'd devised for my previous patches...

Lumix Raider: The Last Revelation

While I wasn't able to recruit Angelina Jolie to star in this epic reveal, I did find a nice set of tombs where she would've looked stunning:


This technically flawless video was taken in Native 1080p24 mode on a hacked GH1 with a Leicasonic 14-50mm f2.8-3.5 zoom lens, mounted on a Manfrotto 560B monopod. Isn't it great what fabulous toys we have to play with these days?

Blackout-Powell Native 24p Patch Downloadable PTool INI Files

*** WARNING ***
The Blackout-Powell Native 24p Patch will not work properly with previous versions of PTool.
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

The zipped INI files below 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 GH1 v1.32. The settings contained in the INI file will automatically be installed in the "B" button at the bottom of the PTool main window.

Note that with these PTool Settings files, you may at any time re-install the original Panasonic GH1 v1.32 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 Blackout-Powell Native 24p Standard Patch v2.zip

View attachment Blackout-Powell Native 24p Anamorphic Patch v2.zip
 
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The Blackout-Powell Native 24p Patch eliminates the insidious corrupted and empty frames that have plagued previous attempts to produce a stable, non-interlaced 1080p FHD video mode on the GH1. However, as long experience has shown, the GH1's AVCHD codec is subject to occasional recording failures when overstressed with highly detailed, sharply focused subject matter. Here's some tips on how to spot and deal with these pitfalls, along with additional details on the patch's useful options.

Do Not Fear the Flowers!

A short video that shows a somewhat menacing bush full of brightly colored, windswept flowers:


Contrary to what you may have read, the GH1 has little difficulty coping with scenes like this. While there are lots of details, this type of shrubbery has gently rounded leaves and flowers that blend sweetly together. Also note how the codec muddies the details on the grass in the lower right corner, a sign that the scene demands more detail than the camera can encode with this patch's 55Mbps maximum bitrate. If you download the original MTS file from Vimeo, you'll find it runs at a moderate 46Mbps average bitrate. This is typical of highly-detailed videos recorded with the Blackout-Powell Native 24p Patch.

How to Handle the Ugly Details

This clip exposes some seemingly nondescript shrubbery you might find lurking just about anywhere:


What's dangerous about these bushes is not just the pointy tangled mess, it's the sharp, high-contrast edges of the bare dry branches. While the GH1 is blessedly free of the multi-colored moire artifacts that plague cameras like the Canon 5D MkII, Panasonic cameras are prone to generating a more subtle type of aliasing. Sharp-edged details that exceed 1080 lines of resolution can cause the camera's image sensor to produce hyper-fine aliasing artifacts that artifically exaggerate the sharpness of the digitized image. These spurious details can at times provoke the AVCHD encoder into producing excessively high bitrates, which may cause the recording to stop abruptly.

In the video above, I used a Tiffen Soft FX3 diffusion filter to soften the harshest of the brambles sharp twigs. This kept the video bitrate within a safe margin without defocusing the image or significantly reducing exposure levels. In broad daylight, however, I find the Soft FX filter produces a subtle white halo around brightly lit objects. I've toned down this side-effect in the following clip:


The video above was shot with a Tiffen Black Diffusion FX3 filter. It has a similar softening effect that safely controls the maximum bitrate. In addition, the fine black net in the filter absorbs the halo effect, producing an image with a closer tonal balance to the original. Unfortunately, I'm not able to post a link to an unfiltered version of this video - every attempt I made to shoot it with the bare lens failed immediately!

More of the Good Details

The Blackout-Powell Native 24p Patch has been tested to work on GH1 cameras in both NTSC and PAL modes, supporting 1080p video in both 24p and 25p frame rates, and 720p videos in both 50p and 60p. All four modes use a 12-frame GOP and produce videos of highly detailed scenes with an average bitrate of around 45-50Mbps and a maximum bitrate of 55Mbps. For single-take, long-duration video shoots, I recommend using the 720p "H" mode, which has been tested to reliably span videos into multiple MTS files larger than 4GB.

I've also developed a newly optimized MJPEG HD mode for this patch, which can record 720p videos in 4:2:2 color depth with an anamorphic frame as wide as 1920 pixels. In addition to its use with 1.5X and higher anamorphic lenses, this intra-frame codec provides maximum horizontal resolution for green-screen rotoscoping purposes. When used with a normal non-anamorphic lens, it can be vertically stretched in post to match the full 1080p resolution of AVCHD Native 24p videos. The MJPEG HD mode can also be customized in PTool to record in any screen width from the standard 1280 up the 1920-pixel default setting. (For best results, always specify a screen width that's evenly divisible by 8.)

Practical use of anamorphic lenses on the GH1 is discussed in detail in the following thread:
Anamorphic Cinemascope in Native 1920x810 MJPEG Mode

Additional points of interest

* All AVCHD videos produced by the Blackout-Powell Native 24p Patch should play back reliably in-camera. The 1920x720 MJPEG videos produced by this patch will not be playable in-camera.

* Peak bitrates are obtained only with well-lit, sharply-focused, highly-detailed subject matter. Average scenes will produce average bitrates.

* If shutter speed is set longer than the frame rate (e.g. slower than 1/60 at 60p), low-quality video files may be produced.

* AVCHD 4GB file-spanning for long video takes may not work reliably at high bitrates. For reliable recording of takes longer than about 12 minutes, I recommend selecting the "H" video mode instead of "SH". This will produce average bitrates of about 28Mbps in 720p50/60 modes.

* For extended recording times at moderate bitrates, selecting the "L" video mode instead of "SH" will produce bitrates comparable to the camera's unhacked SH video mode.

* While AVCHD bitrates may drop to very low levels in extremely dark situations, this patch should continue to record even in total darkness.

* I recommend using the camera to format your SD card at the start of each shoot, to guard against SD card memory fragmentation.
 
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nicely done! i just have bought a GH1 this week and hacked it. Can you elaborate more on the settings and specs that can be achieved and that you've used for the patch?
 
Thanks so much for this--just curious if you had tried 64 instead of 54 MBR which is what I have been using. I'm sure you have more experience with the pitfalls than me.
I'm going to load it right now!
 
DrDave said:
...just curious if you had tried 64 instead of 54 MBR...
Click to expand...
If you set an Overall Bitrate higher than 54M, the maximum possible bitrate can reach almost 75Mbps. This patch limits the maximum bitrate to 55Mbps, which I believe provides a greater margin of stability for the Native 24p hack.
 
lpowell, thanks for all of your hard work. I have installed tonight and will shoot some tomorrow.

In your opinion, what do you think has solved or at least reduced the Native 24p unreliability? Is it "stable" or more robust than in the High Reliability patch? Any idea whether the Digital Diffusion FX 3 is better or worse for toning down the aliasing while sacrificing as little as possible? Any opinion would be appreciated.
 
lpowell, if you have time can you shoot any old scene with the Tiffen Soft FX3 off then on? I'm interested to see how it affects the image, although the clip you posted looks finely detailed.
I'm recording with the new patch now, so far smooth with Transcend Class 10 32gb.
 
BJMarsh said:
...what do you think has solved or at least reduced the Native 24p unreliability? Is it "stable" or more robust than in the High Reliability patch?
Click to expand...
The key to stabilizing the Native 24p patch was finding a way to eliminate the sporatic occurance of empty P-frames in the video stream. Once I figured out that trick, I fine-tuned Blackout's average and maximum bitrates to match. Nothing was more stable than Blackout's original12-frame GOP, which I used in 25, 50, and 60fps modes as well.

While the Blackout-Powell Native 24p Patch produces stable video streams with any type of subject matter, its safety margin is not as high as my Reliable In-Camera Playback Patch. Native 24p is best used in a controlled production environment where technical glitches from any number of sources are routinely handled by doing as many retakes as needed.
 
Had a few failures so far with FHD and a Sandisc 30mb Extreme card and any of the kit lenses. No issues with SH mode.

Just so people don't get a shock like i did, the Mjpeg settings size are 1920 x 720 which lpowell uses for anamorphic shooting. You would need to uncheck that if you want to get regular 720.

Definable more stable than previous but still not fail proof as lpowell says.

But Wow, the detail difference between 720p and 1080p is now huge just looking at individual frames, it's like SD compared to HD.

Thanks for this lpowell and BO

BTW no empty frames in streamparser but some big I frames.
 
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First tests look very good, I'm using the 14-45 indoors at 800 iso and I also shot the lawn with no problems--maybe my grass is too thick! I just love the way 24p looks on this cam.
 
"The stock GH1's video quality is really not that bad, so long as it's daytime and neither you nor the subject actually moves very much. "

My God, lpowell. You're funnier. Is this a byproduct of the collaboration as well? Thanks for your diligent genius. Can hardly believe you finally cracked this final Gh13 flaw.
 
lpowell, Thanks for updating your post on the clarification on the Motion Jpeg sizes . I'm still having issues with FHD failing with FD and kit lenses on well exposed wide shots and long shots with 45 - 200. I've checked my Ptools version it is the latest. I have to go back to reliable again for work, but i've keep the settings on a card for play time.

Also your tomb video, while it looks great only averages 25-26Mbps and doesn't go over 30 for the entire clip ??

The FHD footage i've tried as detailed in my last post all were 38-43Mbps for most of the clips except where i defocused. Are there any setting i can dial down to maybe similar levels as yours? I average 28 - 33Mbps with your reliable patch.

Cheers
 
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Has anyone compared the auto dynamic range as far as stability and IQ with the high bitrate and 24p?
 
Rokkor 50mm at F/2.4 1 hour ten minutes solid 400 ISO, 50 minutes with Panasonic 14-45 at 45mm 800 ISO 20 minutes moving around inside and outside, grass shrubs, books etc. 32gb SDHC class ten transcend all FHD Movie mode. I-Exposure set to standard, not off (can't tell if I like this yet)
 
rambooc1 said:
The FHD footage i've tried as detailed in my last post all were 38-43Mbps for most of the clips except where i defocused. Are there any setting i can dial down to maybe similar levels as yours? I average 28 - 33Mbps with your reliable patch.
Click to expand...
The difference in bitrate you see is the budget the GH1 must allocate to encode an entire 1080p raster for each frame. The Reliable In-Camera Playback Patch needs only record a half-size 540i raster for each interlaced field. While some have found the Reliable Patch robust enough to handle Native 24p in spite of its relatively low bitrate, doing so renders it less able to withstand much abuse. Subjecting the camera to the wild open seas as you do, it's just as punishing to the codec's stability as would be the sand and the surf relentlessly pelting the lens.
 
No this was not Ocean Footage it was in my backyard.

Ok then if there is more bits going to the 25p raster rather than interlaced, should i reduce the overall bitrate and stop the card write errors. Or are the failures the empty bits as you said, I'm not seeing these in any of my footage in stream parser though.

DrDave, are you shooting in creative movie mode or one of the still mode settings?? ISO 400 and 800 are you shooting at night??? I'm lucky to get 5 seconds before card write error.
 
No, I don't believe reducing Overall Bitrate will help. That value is set to provide optimal headroom for the patch's 55Mbps maximum bitrate. If you're not seeing any empty frames whatsoever, then the patch is working as intended. However, 25p demands 4% more bandwidth than 24p, which could be enough to require a GOP adjustment. Perhaps we could try 13-frames for the 25p GOP and see if that shows any improvement?
 
Ok i'll give that a go. Thanks.

Just for fun (actually by accident i forgot to swap out the hack card .. haha) i shot the hack with a 1Gb SD card FAT formatted obviously and then switch out to my 30Mpbs Sandisc Extreme both failed at the same time about 5 seconds.
 
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