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

Fool4UAnyway said:
Do you know what the highest frame rate is, then, that will handle full 1920x1080 MJPEG frames?
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To my knowledge, no one has been able to produce a reliable 1920x1080 MJPEG patch. See this thread for more info:

http://www.dvxuser.com/V6/showthread.php?215785-100-Quality-Factor-MJpeg-Settings-%28very-low-compression-class-10-required!%29

(How) do the frame rate halving settings, 60->30 and 50->25, affect any of the AVCHD and MJPEG hacks?
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This patch converts the AVCHD 1280x720 modes from 50/60 fps to 25/30 fps. On the GF1 and G2, it simply repackages the native 25/30 fps video stream inside a true 25p/30p MTS file. On the GH1, this patch actually cuts the sensor scanning rate in half, from 50/60 fps down to 25/30p.

I use the 720p 25/30 fps patch in my Fast Action 3-Frame GOP Patch to produce videos with 10 key-frames per second. This makes it useful for recording complex motion that compresses poorly with a long-GOP codec. More info on this patch here:

50Mbps AVCHD Fast Action 3-Frame GOP Patch
 
Hi lpowell. thanks for all your patches. it's awesome.

So does this patch completely remove the ability to do 1280x720 @ 50/60 fps or is it accessible with one of the lower modes? I'd like to have 50/60fps as an option if possible without changing cards.

Also, which has better quality, AVHCD or Mpeg? I'm not farmiliar with 4:2:2 colour, but does it mean that the colour is a lot better in MPEG mode? I've read that originally on the unhacked GH1 that the AVCHD mode is much better than MPEG, but do all these patches completely negate the difference? or improve the MPEG quality over AVCHD?

What would be the correct way to scale the 1920x720 video up to 1920x1080 with after effects? Do I just create a new composition @ 1920x1080, drag the movie into it, and then manually scale the frame of the inserted movie up to 1920x1080 so it fills the screen?
 
The Blackout-Powell Native 24p Patch fully supports all AVCHD 720p modes at both 50p and 60p frame rates. Like the 1080p FHD mode, 720p SH mode bitrate with highly detailed scenes averages 45-50Mbps, 55Mbps max.

MJPEG mode records a 1920x720 frame in 4:2:2 color depth at about 50Mbps bitrate. This makes it useful for green-screen color keying. It comes out of the camera in a stretched 1.5:1 anamorphic aspect ratio. This can be easily corrected in post, simply by upsampling the video frame vertically from 720 to 1080 pixels high.
 
evilgeenius said:
What would be the correct way to scale the 1920x720 video up to 1920x1080 with after effects? Do I just create a new composition @ 1920x1080, drag the movie into it, and then manually scale the frame of the inserted movie up to 1920x1080 so it fills the screen?
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if you drag & drop the 720 footage onto a 1920 x 1080 comp, right click the footage and select > transform > scale > fit to comp.

this will scale it to fill the entire 1920 x 1080 frame.
 
Quick comparison, GH13 BP vs GH2 at 800 ISO with 14-45 at 45mm, f5.6
IMHO, the GH13 BP looks awesome, and even less noisy, obvious difference is the moiree is better on the GH2 (and the sensitivity is different....)
GH2 resolves a tiny bit more detail, but the GH13 BP looks good--may have to keep it, sigh.
The chart BTW has lots of ink splatter and tiny lines--it was a mistake but I like it because of all the random crud.
http://vimeo.com/21712718
Password is (drumrollllll)
Blackout

Also--picked up a Tiffen FX soft 3 for $12 on eBay, will redo the test with the filter on when it arrives.
 
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In the MJPEG mode of this patch, there seems to be a lot of compression artifacts. Not huge blocks, just small blocky-ness that shows up along edges or slow color gradients. Also, the audio quality of the on-camera mic (not that I actually use it much anyway) is significantly lower than either of the AVCHD frame rates.

Look at the blue screen behind the subject. I've obscured her face since I don't have her permission to post this.

AVCHD 720p60 Frame grab
00315.jpg


MJPEG 1920x720 scaled to 1920x1080 frame grab
P1010165.MOV.jpg
 
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CColton said:
In the MJPEG mode of this patch, there seems to be a lot of compression artifacts. Not huge blocks, just small blocky-ness that shows up along edges or slow color gradients.
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On a featureless background such as this, the AVCHD encoder will downshift its bitrate and suppress more of the noise than the MJPEG encoder. In addition, we can also see the difference between the coarser 4:2:0 color depth of the AVCHD encoder versus the 4:2:2 color depth of the hacked MJPEG encoder. The result is a clearly defined border on the darker blue color on the left side of the AVCHD image. With the MJPEG encoder, there is instead a cluster of random dithering over a broader background area, which is the best it can do to encode the subtle blue gradient with the limited 8-bit precision of its color components.

To minimize the background noise, it may help to increase the illumination and/or exposure on the blue screen. You could also try flattening the gamma on the blue channel using color correction in post.

The other thing that stands out to my eyes is how well the vertical resolution of the MJPEG image holds up when uprezzed from 720 to 1080 lines. Thanks to the 4:2:2 color depth, the diagonal edge of the model's neck shows virtually no blocky color artifacts. This is the major advantage of the patch's 1920x720 MJPEG mode.

The 16Khz PCM audio quality in MJPEG mode is inevitably lower than the 48khz Dolby Digital encoder used in AVCHD mode.
 
I will give this patch a test (as a pal user) but have been currently using the below settings with no write errors at all with transcend 16gb card and 14-45mm,20mm shooting foliage grass anything
Ive been using this for quite a few months now

Avchd goes between 44mb-50mb in high details. It crashes instantly in 24p but super stable in 25p. Gorgeous footage.


Comment=25p & full mjpeg
SD_Card=Any
Camera=GH1 v1.32
[Settings]
Prevent version compare=Checked
Third-party battery=Checked
30min limit removal=Checked
PAL<->NTSC Menu=Checked
720p30 420->422 color sampling=Checked
E1 Quality=400
E1 Table=4
E2 Quality=300
E2 Table=4
E3 Quality=250
E3 Table=4
E4 Quality=188
E4 Table=4
Native 24p/25p=Checked
Video Bitrate FHD/SH=50000000
Video Bitrate H=44000000
Video Bitrate L=32000000
Overall Bitrate=56000000

Why would it be unstable for 24p but stable for 25p?
 
lpowell said:
On a featureless background such as this, the AVCHD encoder will downshift its bitrate and suppress more of the noise than the MJPEG encoder. In addition, we can also see the difference between the coarser 4:2:0 color depth of the AVCHD encoder versus the 4:2:2 color depth of the hacked MJPEG encoder. The result is a clearly defined border on the darker blue color on the left side of the AVCHD image. With the MJPEG encoder, there is instead a cluster of random dithering over a broader background area, which is the best it can do to encode the subtle blue gradient with the limited 8-bit precision of its color components.

The other thing that stands out to my eyes is how well the vertical resolution of the MJPEG image holds up when uprezzed from 720 to 1080 lines. Thanks to the 4:2:2 color depth, the diagonal edge of the model's neck shows virtually no blocky color artifacts. This is the major advantage of the patch's 1920x720 MJPEG mode.
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Sounds like an accurate assessment. The noise is not quite as bad as I had initially thought, and the vertical resolution does hold up well, so I think on the occasion that I need 30p for broadcast, I'll use MJPEG instead of AVCHD 720p30, which is what I had been using (although normally I shoot 1080p24 unless I need slowmo).
 
mimirsan said:
I will give this patch a test (as a pal user) but have been currently using the below settings with no write errors at all with transcend 16gb card and 14-45mm,20mm shooting foliage grass anything
Ive been using this for quite a few months now

Avchd goes between 44mb-50mb in high details. It crashes instantly in 24p but super stable in 25p. Gorgeous footage.

Why would it be unstable for 24p but stable for 25p?
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The 24p frame rate is 23.971 fps not 23.976 as it should be. Maybe thats why people running 25p are not having any problems
 
I'm sure there is a silent majority out there (including myself until... now) who really appreciate all the work that Tester13, Powell, Blackout et al. have put into making a good camera into a great camera. We continue to reap these excellent benefits and now have a plethora of delightful patches to pick from! So, thank you!
 
lpowell, if wish to optimize SH 720p 50fps for high action (like the on water footage you have seen me shoot) and ignoring any effect it might have on FHD mode, what in your opinion would be the best settings to use based on your research so far.

ie - i just want the best 720p 50fps footage that the hacked GH1 is capable of at the expense of disabling FHD mode.

Thanks, Rambo
 
rambooc1 said:
lpowell, if wish to optimize SH 720p 50fps for high action... what in your opinion would be the best settings to use based on your research so far.
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At 720p50, the Peak Performance Patch can record at up to 75Mbps peak bitrates, which gives it the ability to handle the extremely complex motion vectors you see in sunlit ocean waves. However, its long 26-frame GOP generates less than two key frames per second, and this may not be often enough to handle fast panning without some blurring of details. Unfortunately, this patch needs a long GOP to insure stability.

The Fast Action 3-Frame GOP Patch is specifically designed to handle complex motion by recording a key frame every tenth of a second, with a peak bitrate of 55Mpbs. However, the PAL version works at 25fps, which may look a bit choppy in your case.

The Blackout-Powell Native 24p Patch may actually strike the best balance between bitrate and GOP-length at 50fps. It has a peak bitrate of 55Mbps with a 12-frame GOP. You might want to try various GOP settings with this patch to optimize it for your own shooting conditions.
 
lpowell said:
Not according to Adobe Premiere Pro CS5. When I import the Native 24p MTS files, it identifies them as 23.976 fps.
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I'm getting 23.976 as well, but I haven't clocked it. It hasn't drifted, though. Do you have an MTS file with that rate?
 
lpowell said:
At 720p50, the Peak Performance Patch can record at up to 75Mbps peak bitrates, which gives it the ability to handle the extremely complex motion vectors you see in sunlit ocean waves. However, its long 26-frame GOP generates less than two key frames per second, and this may not be often enough to handle fast panning without some blurring of details. Unfortunately, this patch needs a long GOP to insure stability.

The Fast Action 3-Frame GOP Patch is specifically designed to handle complex motion by recording a key frame every tenth of a second, with a peak bitrate of 55Mpbs. However, the PAL version works at 25fps, which may look a bit choppy in your case.

The Blackout-Powell Native 24p Patch may actually strike the best balance between bitrate and GOP-length at 50fps. It has a peak bitrate of 55Mbps with a 12-frame GOP. You might want to try various GOP settings with this patch to optimize it for your own shooting conditions.
Click to expand...

So would you now recommend this patch instead of your High Reliability patch for 720/50 shooting? I shoot 720/50 basically 99% of the time and am very happy with your High Reliability patch, always happy to push for better quality where possible though.
 
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