Broken codec concern, maybe me

Im trying to see the point in this thread.

Its been pretty much shown and talked about to death that the avchd GH2 codec is not 100% robust...AVCHD isnt anyway....c'mon people do you really expect it to be?

The wierd blue banding issue is more of a concern.

Just go enjoy the camera for what it is...if your not happy why not sell it/send it back and get a different one?

Or is this complaining just the hope that it will fixed by hack? Should of kept your hacked GH1s and waited. I can say yeah the mud and blockery is gone on my GH1s since hacking them with 44+mb 25p avchd. Banding is something that can be worked around.

Panasonic was never going to deliver high bitrate super clean avchd with GH2 just because the GH1 had been hacked...they delivered a great update from the ORIGINAL "pre hacked" GH1...warts and all.
 
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Energy80s said:
My hacked GH1 is the same. It's simply the fault of the AVCHD codec. I Have shot material is very bright sunlight and shadow areas still go to complete mud - even at high bitrates. I had to scrap an afternoons shoot after virtrually every shot was ruined by this. The only option is to re-frame and just realise that here are certain shots that AVCHD-based cameras are never going to accurately capture.

One thing I did notice was that this was pretty much absent with 720p50 material - even on a stock GH1 - and also the MJPEG recordings, although as they are 30fps they are totally useless ofr anyone outside of America/Japan.
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Ok. Good to know. Thanks for the lowdown.
 
mimirsan said:
Im trying to see the point in this thread.

Its been pretty much shown and talked about to death that the avchd GH2 codec is not 100% robust...AVCHD isnt anyway....c'mon people do you really expect it to be?

The wierd blue banding issue is more of a concern.

Just go enjoy the camera for what it is...if your not happy why not sell it/send it back and get a different one?

Or is this complaining just the hope that it will fixed by hack? Should of kept your hacked GH1s and waited. I can say yeah the mud and blockery is gone on my GH1s since hacking them with 44+mb 25p avchd. Banding is something that can be worked around.

Panasonic was never going to deliver high bitrate super clean avchd with GH2 just because the GH1 had been hacked...they delivered a great update from the ORIGINAL "pre hacked" GH1...warts and all.
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I'm not complaining, I am just posting my personal observations in an attempt to understand if what I am seeing is the result of a faulty camera or inherent to the camera (or codec) design. I initially thought I had a faulty camera but as I continue to read this thread I am beginning to think otherwise. I only recently acquired the GH2 and have not had any direct experience shooting with the GH1. I agree we should be out there enjoying the camera, however I think threads like these sometimes give us insight into the nature of the camera, and how best to shoot with it to avoid the technological constraints.
 
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mimirsan said:
Im trying to see the point in this thread.

Its been pretty much shown and talked about to death that the avchd GH2 codec is not 100% robust...AVCHD isnt anyway....c'mon people do you really expect it to be?

The wierd blue banding issue is more of a concern.

Just go enjoy the camera for what it is...if your not happy why not sell it/send it back and get a different one?

Or is this complaining just the hope that it will fixed by hack? Should of kept your hacked GH1s and waited. I can say yeah the mud and blockery is gone on my GH1s since hacking them with 44+mb 25p avchd. Banding is something that can be worked around.

Panasonic was never going to deliver high bitrate super clean avchd with GH2 just because the GH1 had been hacked...they delivered a great update from the ORIGINAL "pre hacked" GH1...warts and all.
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Sorry, but I had the Gh1, shot plenty, not once did I see the codec do this unless it was extremely under exposed. Unhacked. It had banding, but there wasn't a ton of blocky artifacts in underexposed area's. I could get a clean image out of low ISO's on the Gh1, not so much on the Gh2. The point of this thread at the beginning was to see if it was just a setting I had wrong, and if anyone else had experienced it. I like the Gh2 so far, just a big disappointment seeing the codec's flaws. One I hadn't dealt with since the D90. Who says nobody is enjoying their camera. I'm sure plenty of people enjoy their cars, but get mad that it rattles.
 
Low-light is an inherently dodgy situation for a real-time, variable bitrate AVCHD encoder. Its encoding strategy is based on the premise that the image is composed of prominent, adequately exposed areas that deserve more bitrate than surrounding under-exposed and/or over-exposed background details. If there are no well-lit, sharply-focused objects in a frame, the AVCHD encoder will produce low-bitrate compact files that use minimal SD card space. AVCHD is, after all, designed for highly efficient compression, and not for the highest image quality under all possible shooting conditions.

In practice, I always use the GH13's 65Mbps MJPEG encoder for dimly lit scenes.
 
why can't the codec be "locked" on 24Mbs and not make
Lower variable "travelings"- that's what the hack is for?
 
roei z said:
why can't the codec be "locked" on 24Mbs - that's what the hack is for?
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AVCHD is a subset (designed by Panasonic and Sony) of the H.264/AVC family of encoders. There are more complex AVC encoders capable of maintaining constant bitrates, I-frame-only encodings, and 10-bit 4:2:2 color depth. At this point in time, consumer cameras like the GH1/GH2 are built with simpler AVCHD encoders that produce highly compact video files for convenient use.

While the GH13 hack is able to increase the maximum sustainable bitrate of the AVCHD encoder, it cannot alter the codec's built-in encoding strategies. If you don't present the AVCHD encoder with well-lit, sharply-focused, highly-detailed scenes, it will not make full use of its maximum potential bitrate.
 
Car3o said:
Sorry, but I had the Gh1, shot plenty, not once did I see the codec do this unless it was extremely under exposed. Unhacked. It had banding, but there wasn't a ton of blocky artifacts in underexposed area's. I could get a clean image out of low ISO's on the Gh1, not so much on the Gh2. The point of this thread at the beginning was to see if it was just a setting I had wrong, and if anyone else had experienced it. I like the Gh2 so far, just a big disappointment seeing the codec's flaws. One I hadn't dealt with since the D90. Who says nobody is enjoying their camera. I'm sure plenty of people enjoy their cars, but get mad that it rattles.
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Y'know I do see your point...I spoke to a friend of mine today who sold his GH1 bought a GH2 over xmas and is sending it back with the words to me "not worth spending the extra cost over a GH1"...which came as no suprise to me and this is why I didnt rush out to buy one until trying first hand especially now were spoiled by the hack.

What you going to do? hold on to it live with it and hope for a hack or send it back?

This is sadly the risk of being a early adapter...Panasonic seems to have stumbled with the ball again.
 
lpowell said:
AVCHD is a subset (designed by Panasonic and Sony) of the H.264/AVC family of encoders. There are more complex AVC encoders capable of maintaining constant bitrates, I-frame-only encodings, and 10-bit 4:2:2 color depth. At this point in time, consumer cameras like the GH1/GH2 are built with simpler AVCHD encoders that produce highly compact video files for convenient use.

While the GH13 hack is able to increase the maximum sustainable bitrate of the AVCHD encoder, it cannot alter the codec's built-in encoding strategies. If you don't present the AVCHD encoder with well-lit, sharply-focused, highly-detailed scenes, it will not make full use of its maximum potential bitrate.
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thanks,
so the hack doesn't solve this.
so is it an option to prefer some decent looking noise with some tweaking and avoid the bitrate failure?
 
It's really too bad that AVCHD became so poular and I've always thought it was a terrible idea to begin with. It's efficient....SO WHAT!! Storage for data is much easier to deal with than the processing power people have had to purchase to deal with it. Sure it's great for people who just watch stuff on their TV through the HDMI. They get small file sizes and good value for their sdhc cards....but for editing it's TERRIBLE. PERIOD. A high bit rate MJPEG would be much better for serious cameras. Big files...SO WHAT? It could just be an option for those who would care to use it...everybody else could stick to the AVCHD.

When I had my GH1, I just used the motion jpeg...because it looked good to me and I could just drop it right into the timeline and edit away.
 
roei z said:
...is it an option to prefer some decent looking noise with some tweaking and avoid the bitrate failure?
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Possibly, but unlike noise grain in a still photograph, random video noise tends to swirl around in a distracting manner over time. Unless it's Fixed Pattern Noise, which remains static in a distracting manner while you're panning the camera...
 
roei z said:
why can't the codec be "locked" on 24Mbs and not make
Lower variable "travelings"- that's what the hack is for?
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I think that is a great idea, even if it is remotely possible. After all, it should require less CPU overhead for the onboard processor.
Even if it is unlikely, I would imagine that there could be a software switch to turn VBR off.
 
DrDave said:
I think that is a great idea, even if it is remotely possible. After all, it should require less CPU overhead for the onboard processor.
Even if it is unlikely, I would imagine that there could be a software switch to turn VBR off.
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well Ipowell says it's not really possible by the definition of using AVCHD in the first place :(

* so in a way, there's no real use of shooting with AF100 on AVCHD for the same reason, right?
 
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roei z said:
...so in a way, there's no real use of shooting with AF100 on AVCHD for the same reason, right?
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The AF100 uses an AVCCAM implementation of AVCHD with a video-optimized image sensor and probably has additional hardware resources available to assist with real-time image capture and encoding. I'd be surprised if it were not capable of producing higher quality video images than the much cheaper GH2.
 
So is the consensus that the GH1(3) with its higher bitrate is a more robust implementation of the AVCHD codec and less likely to break up than the lower bitrate GH2 at 24p?
 
Gh2 is the way to go.
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Exactly. I've seen some really nice stuff shot with it already, so, it means that it should work nicely. Every time a new cam comes out is deja vu all over again. Some people seem to have so many issues with it that they should just return it and buy a real film camera. But maybe they will have issues with those too.
 
Car3o said:
So...what you're saying is you're in no rush to buy a Gh2? Glad that's all cleared up. I couldn't tell if you really meant it after you've posted it several times before in every other thread.
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No, that's NOT what I'm saying, but what I am saying is I'm in no rush to buy the GH2. :violent5:

Seriously just trying to help you not feel 'insane' and that you got a 'bad' camera.
They all do it.
 
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