1) If you mean magnified view, no, it is technically impossible.
2) It requires a look. If something is not present it usually means that whole logic also is not in the code.
3) As for start frames, we'll see.
4) no 1080p50 or p60 modes exists, this is my understanding.
30p already exist and working in default GH2.

BASIC FACTS (taken from known resources) (@ALL PLEASE CAN WE ADD TO THIS!!!!)
________________________________________

1. GOP
means Group of Pictures.

There are closed or open GOP. Closed GOP will make compression less efficient. If the GOP is not closed and you use B-frame, the last B are dependent to the next I-frame. This makes the movie harder to cut. If all GOP are closed you can cut between the B and I frame. If the GOP's are open you have to delete the last two B-frame and cut between the P and I.

A GOP begins with an "I" frame (Intra-coded), followed usually by a number of "P" (predictive) and "B" frames (Bidirectional).

Each GOP is independant: all frames needed for predictions are
contained within each GOP.

GOP's can be as small as a single I frame, or as large as
desired, but usually no more than 15 frames in length.

The longer the GOP, the more efficient, but less rubust the
coding.

---------

2. What the GOP frames I, P & B mean

I frame

"Intra-coded" frames : average 7:1 reduction.
Like JPEG, every video frame is broken into blocks of 8x8
pixels of Y, R-Y, and B-Y.
Blocks are grouped into "macroblocks" of 16x16
Macroblocks are grouped horizontally into slices which
have similar average block levels.
Multiple slices form a frame, and these frames are the
resulting "I" frames.

P frame
P frames are predicted based on prior I or P frames plus
the addition of data for changed macroblocks.
Average about 20:1 reduction, or about half the size of I
frames
p frames have to be decoded before the B frames between them.

B frame
Bidirectionally predicted frames based on appearance and
positions of past and future frames macroblocks.
B frames require less data than P frames, averaging about
50:1 reduction.
B frames require more decoder buffer memory because 2-4
frames are compared during the reconstruction process.
B frames also require manipulation of the coding order:
frames moving from the coder to the decoder are NOT in
presentation sequence.

-------

3. Extended GOP Stuff
The longer the GOP the lower the bitrate you can use and still get the same quality.

The advantage of long GOP is that it achieves better compression, and thus yields higher video quality than a shorter GOP recording at the same bitrate.

When using constant quality encoding GOP size effects file size. What is the GH2 doing - does it switch to a constant quantizer mode with different GOP sizes? If its constant, then the output file gets smaller as the GOP size increases.

As you go from a GOP length of 1 through 4, the filesize and bitrate drops dramatically but after about a GOP length of 5-6 the filesize and bitrate levels out. ie there is not much to gain in terms of filesize and bitrate by using a longer GOP than 5 or 6.

A GOP of 1 will give all I frames.

A GOP of 3 will give a sequence of IBB frames in the recording and no further P frames after the initial first half second burst (GH2).

A GOP of 5 will give a sequence of IBBPB frames and no further P frames after the initial first half second burst (GH2).

Its best to run GOPs in multiples of 3 (ie 1, 3, 6, 12, 15, etc...) to avoid problems like losing P frames.

The standard unhacked or base GOP of a GH2 (AVCHD standard) at 1080p24H is GOP 12 = IBBPBBPBBPBB.

A Low GOP with high bitrate gives a 'cinematic motion' look and is preferable for some filmmakers. (GH2 users)

MPEG2 GOP encoding works by referring to one frame before the current frame and one frame after.

AVCHD H.264 encoding is more powerful in that it uses four frames at a time, consequently more blocks in these frames can be used for compression of the intended block in the current frame, thus enhancing effeciency.

-----

4. Compression, pixel blocks & Quantisation

AVCHD uses Interframe compression.
Hi Quality image compression is achieved through optimised DCT (Discrete Cosine Transform) block units.

In AVCHD H264 Main Profile, the block unit is 4 x 4 pixels, enabling motion-compensated residual DCT to be applied in finer detail. Compression rate is fixed.

In AVCHD H264 High Profile, the block units can use both 4 x 4 pixel and 8 x 8 pixel blocks in the same frame. Optimal frequency transformation is applied depending on patterns and movements: 4 x 4 pixel blocks are used for detailed parts, whereas 8 x 8 pixel blocks are used for flatareas in the same image.

High profile improves image quality by processing relatively evenly patterned parts such as the sky, using high transformation performance 8 x 8 pixel blocks, allowing more information distribution (ie bits) to detailed parts in the same image. Compression rate is thus variable.

You can receive optimal compression through quantisation matrixes.

Image distortion due to data compression is often more noticeable in flat patterns and can be visually disregarded in detailed patterns. A charateristic of the human visual system!

With some image patterns, a uniform compression might cause image degradation. Employing a quantisation matrix therefore enables the retention of high image quality by maintaining the original image properties, achieved by applyiing low compression to the flat areas of an image.

Therefore flat parts of an image are low frequency - image degradation is controlled by fine quantisation (low compression) and busy parts are high frequency - image degradation does not stand out in rough quantisation (high compression)

A 1/4 Pixel accuracy is used in motion estimation to get the best fit for each macro-block. say you have a panning camera and each frame the picture hasnt moved an entire number of pixels across the screen then 1/4 accuracy helps get the predicted macro-blocks in a much better possition. This isnt used in I-Frames because motion estimation isnt used in I-frames as it is basically a JPEG encoded frame using a different Quant value (typically 16).

The use of B-Frames does improve the compression/quality of the codec by a considerable amount but requires a lot more motion estimation (a large portion of the encoding time) to be done hence the much longer encoding times. B frames are typically 1/2 the size of P-Frames but require more encoding and decoding.

GH2 Quantisation tables consist of integer values.

The Ptool GH2 "Encoder Settings" look like scaling factors for quantisation tables. 720p and 1080i/p seem to be addressed each with 4 progression stages to control A kind of 4-step adaptive matrix. (tbc)

--------

5. Bitrates
Always keep lower bitrate settings within 95-70% of high bitrate settings.
Otherwise, you'll see a dramatic bitrate drop in the low modes. (GH2)

There is currently a known drop in bitrate in the first frame set or GOP - known as the blip. Still to find out a definitive answer as to why. (GH2)

Unless HK became European country, no.

@wangc

I already answered this - read hint.
This patch is useful for Europian PAL cameras only.

I have weird logic I think. :P

>Thanks! But I think the hint is a bit ambigious

?
"Enter same increment each time. One is normally enough."

@kanintesova
Please read hints :-) Always use 1 for increment.

I have seen some posts in other threads which recommend saving different versions of the firmware (both original and hacked) onto separate SD cards to enable easily switching from one to another. But does this work? From what I understand the version increment must always be checked. Doesn't this mean that I cannot go back to a previous version without recreating it in ptools? Can anyone clarify this for me? Thanks.

Summit seems to be working, after a few tests and is there any sign of a proper [GUIDE - GH2 Hack - From Flashing to Camera Operation] on at least the basic findings? (PS donated, and will donate more soon). So to fellow noobs Elecard Streameye Slim reports this when you hit the 'i' button using kae's setb.ini file. Plus No record crashing on transcend 32gig type 10 cards.

@belfryman
Of course it is not related to hack in any way. :-)

@belfryman
This is all known for long.
And please, do not crosspost.

@feha
it is weird, I've just tried connecting two different monitors and it's the same with both. As soon as I plug in a monitor whatever record mode I set previously I can only record 1080i and it seems it doesn't matter what I set the HDMI to either, whether it's auto, 1080 or 720 I always record 1080i. If I just plug in an HDMI cable with no monitor on the other end I'm still able to select my record mode, if I connect the other end to a monitor the rec mode option is greyed out and I record 1080i. Weird.