GH2 Flow Motion v2.01 Update

This update addresses reliability issues with HBR, FSH, and SH video modes in both NTSC and PAL. It has been successfully tested for failsafe operation under all shooting conditions and options, including 80% Slow Motion and ETC zoom modes. The stability adjustments in Flow Motion v2.01 should produce little or no visible reduction in motion picture quality in any of the updated video modes.

In response to numerous requests, I've enabled and verified reliable operation of Flow Motion v2.01 with extended ISO levels. By default, all levels up through ISO 12500 may now be selected for use with any NTSC or PAL video mode. In practice, however, levels above ISO 3200 produce considerable noise, which may require excessive bitrate and perceptibly reduce motion picture quality compared to lower ISO levels.

Download the Flow Motion v2.01 Update at the following link:

http://www.personal-view.com./talks/discussion/3337/gh2-flow-motion-v2.01-update-failsafe-hbr-720p-modes/p1

@towi well, it was not the solution, apologies. My GH2 worked without problems for one day shooting HBR, but I emptied my card, format, and it crashed again... Shooting test charts with HBR is strange too : usually it crashes after a cold start, but if I pull out the battery and shoot again, no more crash. Thanks for sharing your settings, I'll give a try :-)

@Lpowell : great news! And thanks for your amazing work, FM 2.0 makes the GH2 shine! 24p is simply amazing. Panning footages are so fluid and movements so smooth that it's hard to belive it's shot with the GH2 :-)

@luxis The stability revisions I'm testing are intended to insure failsafe operation on all Class 10 cards, regardless of their rated maximum bitrates. In my experience, the advantage of the 95MB/sec Class 10 cards are primarily in their ability to support 4GB file-spanning at 100Mbps. Although standard 30MB/sec Class 10 cards are capable of reliably recording individual 4GB files at 100Mbps, they usually fail to span. With Flow Motion v2, you may see a brief write-speed error message when file-spanning fails on slower Class 10 cards, but the initial 4GB MTS file will be saved intact. FM2's 60Mbps 24L, FH, and H modes should span on standard 30MB/sec Class 10 cards, as well as higher rated SD cards.

@LPowell Looking forward! Thanks for all your great work!

@rapsoe for logging its great - rain or no - trust me even in broadcast progs - the chaps n chapesses that log and capture any ingest ... rain? Had a QC dept this week pass an audio mix (that I hadn't even laid back until the day after i.e. the all the way to 0 offline, crunchy drunk disco dancer music edit mix) on a well (multi million watched) series in it's nth series - joy. Ravensbourne where art thou with your brown cords and flares lol

@Frame: I don't know/use Premiere, so I cannot recommend any details on it. But generally speaking, the idea is not to avoid the first/last frames when "importing" the clips (assuming that "import" here means: telling the software about the available .mts files - without transcoding them into some different format), but to set the "in" and "out" points of your clips (afterwards, e.g. when putting them into the timeline) such that their first and last 12 frames won't be used as a source for your final output rendering.

You mention that the part you uploaded was 30s into a larger file: Yes, and the excerpt starts with data for an I-frame, followed by data for b-frames that have a Presentation Time Stamp (PTS) that is before the PTS of the I-frame (because the file needs to contain frames in an order that allows decoding of P- and B- frames based on differences to frames that were decoded before), but the second I-frame that is needed to interpolate the 2 B-frames is not part of the file (it would have been in the part before the excerpt). So the decoder sees two B-frames that it has only one reference frame for, and at that point it may decide to discard or partially decode those frames. ffmpeg seems to opt in favor of the partial decoding under certain circumstances: when there already was at least one other decoded frame. This would explain why ffmpeg does not decode the B-frames with missing reference when cold-starting a replay, but it does decode those B-frames both when looping (using the last decoded frame from the sequence instead of the missing reference) and probably also when "seeking" in a file - e.g. when the NLE software tries to single-step to a frame where to start, but has already decoded others in the process of getting to the right position.

The reason why I see that effect often is that my workflow starts by cutting relevant parts from the .MTS files I recorded in the compressed domain (without re-encoding). I need to do this, as I often take lots of long shots (the "actors" being animals not allowing me to request their action on command), and if I would not decimate the material quickly after shooting it, it would use up excessive amounts of harddisk space. So I live with the mentioned work-around until I can find a better solution, which could be:

• fixing avidemux26 to get rid of the incomplete B-frames when cutting in the compressed domain
• changing kdenlive/mlt/ffmpeg to do the "seeking to the right position" in a different way, avoiding to produce initial garbled frames.

@ Movist Lovers. Since it seems that I've been responsible for few of you switching to Movist I just want to add a word of caution: Movist playbacks might suffer from the Tarkovski Rain Effect identified by @Frame. As @karl pointed out, the rain doesn't actually seem to be in the MTS footage (at least all my ProRes conversion with FCP7's L&T do not to exhibit any such effect). My conjecture is that all the players/converters based on FFmpeg as Movist is will exhibit that effect. Another conjecture can be that, on slower computers, the FFmpeg libraries, instead of forcing the players to skip frames, handle to them incomplete ones. Obviously all this would have to be verified, but the good news is that if you transcode your MTS wisely you won't be reminded of any Russian master.

Tx.tor patch my video...Gf3 Flow motion v.2.0

@larch ETC gives bad results in high iso and/or underexposed shots, i think it actually doubles the noise plus other weird stuff. i works well in low iso with good light(bright daylight) also it gives less sharp images most of the time.at least this is my experience with it regardless of patches or not.

as far as the players, look in the previous pages of this thread. classic windows media player should do fine.

@Frame: From your .mts sample it is obvious what happenes: Your .mts file contains at least one frame that is not correctly decodable, because it references another frame that is not part of the file:

[h264 @ 0xfd6920]Missing reference picture [h264 @ 0xfd6920]decode_slice_header error [h264 @ 0xfd6920]concealing 8160 DC, 8160 AC, 8160 MV errors

Some players will either just skip such undecodable frames silently, others will try to decode "as much as possible" from the differential data, but as they use a wrong reference picture (usually just the one they decoded last) this will result in some artifacts. See attached a screen shot of only the broken frame "decoded" in such a way.

It seems that the encoder you used to render your output file was making use of such an incomplete frame, but the distortion is not as clearly visible in the output than it is in your input.

So the good news is: This is not a problem of FM 2.0. It may be, though, an odd behaviour of the software you use when it processes AVCHD files as written by FM 2.0. I have seen similar trouble with other software, too. One work-around I use for that with "kdenlive" is that I never use the first 12 or last 12 frames of a 24p recording - this seems to allow the decoder to decode a few frames before the first one that needs to become part of the output.

Of course GOP1 settings will not result in files that can cause such trouble, but I haven't found any stable-enough GOP1 setting that delivers good quality...

hi guys say being very much a noob here ,where do you go for the flowmotion patch

@diafragna1939 IMO, that kind of question should be asked in PM or over on the "Stable GF2 Settings" thread, please. Let's keep our focus on concerns relative to the FM2 patch, here. I'll answer you over there, on the GF2 settings thread. Thanks!

Downloaded and installed. So far the couple of tests I have done look good. About to go out for a drive to take a few more tests. One thing I have noticed, and I am sure this is teh same for all hacks, if I try and play the footage back in my Panasonic Blu Ray player by inserting the card in the player, the video skips. I am assuming this is normal because of the extra data. I did a quick screen cap of some footage in VLC and the results look great. 24H iso160.