Ok now it's almost clear for me!does this happen even if i have set my camera in pal mode?80% VMM still records at 30p? As to my initial question,regarding quality differneces between hbr 25p and 30p,isn't this dependant on the each settings/patch we use? cause i see that many patches use different parameters for hbr pal and ntsc modes (3gop and 6gop respectively,for example).. Does this happen with FM too? and a last one..when you announced FM 2.01 you wrote that it has stability improvements and no or very small quality decrease..is there any quality decrease ,even minimal, from 2.01 to 2.02? ofcourse stability is the main issue but i'd like to know if there are quality differences and in which modes,so i can choose FM 2.0 in case i don't have stability problems... Thanks again!

Thanks for quick and informative response! I'm also leaning towards 30p (although i'm in a pal country) because i'm shooting for personal use (viewed on a pc monitor or TV with blu ray) and i like the more smooth motion of it...

concerning the VMM 80% and speeding it up in post...is it 20% or 25% in order to have final 30p? also,will the final 30p from speeding up have the same smooth motion as if i have recorded in hbr 30p but with better quality because it shares the 24p settings?

PS sorry for my english..

Trying to decide which framerate to shoot at, i'm testing various settings including FM 2.0.. Except stability,are there any quality differences between pal hbr 25p and ntsc hbr 30p ? If not,i'll save some time from testing both(pal &ntsc modes) in each setting.. same goes for 720 50p and 60p...

@adventsam Filming a live plasma monitor can be challenging. You may need to do some research to determine its native refresh rate, and set your GH2 accordingly.

Thanks @johnnymossville i will, i just hope i can hack it

Hi, next month i will buy my GH2 form Amazon(if you know a better place please let me know), but im want to know if any GH2 can be Hack, Thanks

@lpowell, flicker from plasma tv in background on in-door shots, low light. I swapped to Sanity pal and flicker is gone, horizontal lines are there at certain shutter speed but apart from that no flicker? That's weird. is it a gop thing?

@Alex_K There must be some mistake as there's no way Flow Motion or any patch could alter the AVCHD frame rate.

@karl Thank you for your detailed evaluation of Flow Motion v2.02. I downloaded and examined the frame grab you posted above that shows artifacts in HBR mode. Are you certain this frame was deinterlaced correctly by the decoder? It has some defects that look similar to the artifacts I saw in one of my own frame grabs that I initially thought were due to interlaced encoding effects. (Click on the second attachment of the top post on this page):

http://www.personal-view.com./talks/discussion/3337/gh2-flow-motion-v2.02-spans-in-hbr-25p-24h-720p/p6

The artifacts in that image are due to an oversight I made in importing the HBR video into Adobe After Effects CS5.5. The GH2 records progressive HBR videos in exactly the same 1080i file format as interlaced FSH files, and there is no explicit way for an editing program to tell the difference. As a result, After Effects naturally assumes that HBR files are interlaced, and interprets the footage as "Upper Field First", which causes spurious interlace artifacts. To correct this, I had to use AE's Interpret Footage dialog to set Separate Fields to OFF. That eliminates the interlace distortion in the HBR frame grab I first uploaded, which I then corrected. (Click on the fourth attachment at the bottom of that post.)

For anyone using HBR footage in a post-production environment, this is a serious hazard. HBR files are in fact interlaced, even though the image sensor is scanned progressively, referred to as "psF" format. Unfortunately, the fact that it is progressive is not contained in the file and must be manually interpreted for each file.

On the technical limitations of HBR video encoding, it's important to understand how the process actually works. Each I-frame in an HBR video is comprised of a pair of separately encoded, interlaced fields: an "I-field" and a "P-field". The P-field uses the I-field as its reference field, similar to how P-frames are encoded in a non-HBR video. Flow Motion HBR mode uses a 3-frame GOP, with two B-frames following each I-frame. Each interlaced B-field in these two frames use the corresponding I-fields or P-fields in the previous and following I-frame as their reference fields.

In effect, each HBR GOP is comprised of two interwoven 1920x540 field sequences, a 6-field GOP in the form I-p-B-b-B-b. Since each field is half the height of a 1920x1080 frame, it requires half as much data. This is why an HBR video is typically about the same size as a 720p video rather than the size of a 24H video. Each 1920x540 I-field contains close to the same amount of data as a 1280x720 I-frame.

In practice, the crucial factor in HBR image quality is the quantization quality of the P-field in each I-frame. In the unhacked AVCHD encoder, this P-field is encoded with significantly coarser quantization than the I-field. In Flow Motion v2, I created Quantization Tables specifically for HBR mode that encode each P-field at the same level of quality as its reference I-field. When decoded and deinterlaced correctly, this preserves the highest practical image quality that the HBR encoder can produce.

Whether FM2's encoding strategy produces HBR videos that can match 24H perceptual quality is ultimately a subjective judgment. In terms of bitrate, since 24H I-frames require twice as much data as HBR I-fields, 24H video will naturally require more bitrate than HBR. Flow Motion v2 accommodates these bitrate requirements proportionally for each video mode - in 24H turbo mode, peak bitrate can range up to 140Mbps, while in HBR mode, peak bitrate is limited to 100Mbps. Judging from my testing of the GH2's capabilities, these are close to the maximum bitrates that can be reliably sustained with each of these video modes, using 30MB/sec Class 10 SD cards.

@Karl

I see... clearly visible artifacts on that footage. It's strange. I got that kind of "frying leaves" on my previous attempts with INTRA settings on HBR 30p. This is the reason I give a try with FM and on my shots of moving leaves I found no big difference between 24p and HBR. I measured the bitrate for both the clips and I reached the maximum for 24p and 30p for both. The 24p clips looks something like sharper but it's more of a feeling and I cannot see real artifacts like on your image.

Really I don't know....

@Karl @valpopando regarding the actual bitrate...

maybe I'm wrong here but I think it's normal having roughly half of the bitrate. The HBR stream is encapsulated in a interlaced container with the two half frames repeated (PSF) so I guess streamparser already calculates this, it's counting just the real useful transported frames (half of them). This is the reason why on the same identical scene shot on a tripod I get > 100Mbps on 24p and > 50Mbps on HBR 30p. Please, could someone confirm or correct me?

Byeeeee

Thanks lpowell! Used 2.01 all week at a music festival, great looking vid. Did a lot of work with the 14mm Panasonic, very sharp and detailed, good for large groups where you want lots of people in focus. Will try 2.02 this week.

@valpopando: No, I am not a Final Cut Pro X user. Even if the artifacts where somehow related to an erraneous decoding of the .MTS file, that would not explain why the size of the recorded HBR .MTS files divided by their duration calculated to a bit rate of only ~50MBit/s, less than half of what 24H uses for the same scenery.