50Mbps AVCHD Fast Action 3-Frame GOP Patch

The Fast Action 3-Frame GOP Patch upgrades the stock video modes with increased bitrates and improved image quality. You can revert back to the original firmware at any time simply by using an SD card to reinstall Panasonic's GF1__122.bin file.
 
lpowell said:
Yes, 60p has inherent advantages in capturing rapid movement with twice as many frames as 30p. If the GH1 had a 100Mbps Intra-frame encoder that recorded at 60fps, it would be the preferred choice for fast action videos.

Unfortunately, the 60p AVCHD encoder has technical limitations that can degrade its image quality on rapidly moving objects. In order to handle a 60p video stream with practical efficiency, it records only about two key frames (I-frames) per second. For the rest of the frames it encodes only the pixels that have changed from previous frames (P-frames). When there's a lot of fast motion in a scene, the P-frames can require so much data to encode that there may not be enough bitrate left to encode the I-frames in high quality. In extreme cases, there will be visibly degraded regions where the motion looks muddy.

The direct way to improve image quality is to increase the encoder's available bitrate, but with the GH1, there are reliability issues that impose limitations on this approach. An alternate approach for handling fast motion is to increase the number of I-frames in the video. This restricts the amount of motion that can occur between key frames, which can significantly reduce the bitrate required to encode the P-frames.

What I discovered working on this patch is that if I reduced the AVCHD frame rate from 60p to 30p, I could dramatically shorten the GOP to just three frames, producing ten key frames per second. At such a quick rate, there's very little motion between key frames, and the P-frames can be efficiently encoded at relatively low bitrates. That gives you image quality close to what you'd get with an Intra-frame encoder at twice the bitrate.

The shortest GOP I've been able to make work reliably at 60p is 12 frames, which produces five key frames per second. Check out the link in my signature for more details.
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Please could you explain what the purpose of preset bitrate 1 & 2 is? What effect does it have on a G2?
 
Sorry if this is a silly question but is this patch for the GH1 too or just G2 and GF1 cameras?
 
Yes, the Fast Action 3-Frame GOP will work with the GH1 as well as G2 and GF1 cameras. However, its 1080p performance on the GH1 has been superceded by later patches. Check the links in my signature for more details.
 
alainmaurel said:
I have a G2 with the G2___V11 firmware. I have loaded LPowell - Fast Action 3-Frame GOP Standard Patch v2.zip into the latest Ptools using the I button. I have renamed the software G2___V12, put it on the SD card, put that in the G2, switch it on, push the play button and NOTHING happens, as if the camera does not recognize the software. I did not have this problem with the GF1. Any clues?
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hi first thx for your work and second I have the same problem with my g2 as alainmaurel. I downloaded the last version of ptool then I downloaded your settings. I used the G2_v11 firmware and then I clicked the I button and saved the firmware. Then I renamed it to G2_V12. Then I deleted my SD card and recharged my battery and then I pressed 5 sec the play button. Does somebody have a solution?

thank you
 
Thx for your fast answer. I renamed it like G2___V12. I also tried other setting packs. But nothing worked. If I start the camera and push the play button it only says no pictures on the camera. Is it important to write it G2___V12.bin, normally not or? The file is a bin.

Its my first firmware update on my camera I had from the begginning V 1.1 , maybe this helps
 
Yes, you must copy the filename precisely, try changing only the last digit. Just to be sure, reformat the SD card in the camera and copy the firmware file to the root folder of the SD card.
 
sorry that to bother you but I reformat the SD card. My camera is fully recharged and I put this this file in my root folder: G2__V12 (2 underlines). I also opened the tool as an admin and then renamed the G2__V11 to G2__V12. I downloaded the firmware from http://panasonic.jp/support/global/cs/dsc/download/fts/index2.html. If you extract the orginal file there are 3 underlines like this G2___V11. Now I also tried to renamed it to V11 and V10. I made a picture. I already found out that in the tool there is a hint: Available patches for G2 v1.10, maybe thats the reason?

test.jpg

Now I tried it with 3 diffrent SD cards with diffrent classes and also tried it with renamed files like this G2___V12.bin, becauser after unzip the file from panasonic homepage the firmware file is named like G2___V11.bin this and I also tried it with a diffrent increment number 20 instead of 10. I always recharged the battery during the testing.
 
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Hmm, looks like Panasonic put three underscores in the G2 firmware filename. Underscores are really an albatross aren't they? These types of pitfalls all date back to those bearded brainiacs at Bell Labs. At any rate, the precise filename you should use is this:

G2___V12.bin
 
Does these mjpeg settings affect the avchd? or could i use the timelapser settings instead, on the gh1?
 
lpowell said:
The MJPEG settings in the INI file are completely independent from the AVCHD settings.
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Does that go for all your patches? And would this be the best patch for shooting skateboarding in 1080p pal, where you shoot alot of short clips and can't format after each shot?
 
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