Wrong thread/forum. Tons of this stuff elsewhere. Check the gh1 main forum; this has nothing to do with the hack.
50Mbps AVCHD Fast Action 3-Frame GOP Patch
- Thread starter Lpowell
- Start date
stonebat
Veteran
yes it has everything to do with the hack cuz the hack changes the way it captures each frame. progressive non-segmented 30pN. thats 29.97 "snapshots" per second.
The 3-frame GOP is used only in 720p30 AVCHD modes. Since 1080p24 video is still recorded in its 60i interlaced container, PTool cannot be used to alter its built-in 15-frame GOP. To see the difference, check out the GH13 Stream Parser screenshots I pasted under the FHD and SH frame samples in the second post of this thread:
http://dvxuser.com/V6/showpost.php?p=2100424&postcount=2
The 720p30 MJPEG mode uses an intra-frame encoder that effectively has a 1-frame GOP (i.e. every frame is a key frame). This patch gives it a 65Mbps maximum bitrate and the MJPEG encoder uses it more effectively in low-light conditions than the AVCHD encoder does. With dimly-lit, low-detail images, the AVCHD encoder will inevitably reduce its bitrate. This enables it to record much longer videos than the MJPEG encoder can.
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For half-speed slow-motion playback, I'd recommend using the 720p60 AVCHD mode in my Reliable In-Camera Playback Patch, at 1/120 sec shutter speed:
http://dvxuser.com/V6/showthread.php?t=219132
Naturally, you'll want to import the 720p60 video into a 720p30 timeline in your video editor to achieve the slow-motion effect.
The equation is the same hacked or not. You are asking questions regarding 180 degree shutter rule, and/or slow mo capture shutter speed ratios. These rules (if you can call them that) do not change regardless of the numbers you use. Not being a dick, just trying to get you the answers you need (you would have hours of reading in front of you in other forums, should you choose to look), as well as trying to keep the threads on topic.
So, the 1080p FHD setting is your 40mbps reliable in camera playback setting?
stonebat
Veteran
u r not being a dick. u just didnt quite understand what this particular 720/30p hack does. this latest "i" setting is not really optimized for 2x slowdown. the 180 degree shutter rule does not apply to the setting. i think thats important piece of information to know for those who r going to use this setting.
No, the 1080p24 setting in the Reliable In-Camera Playback Patch is capped at a 44Mbps maximum bitrate. It is the most reliable 1080p patch I know of.
The 1080p24 setting in the Fast Action 3-Frame GOP Patch is capped at a 55Mbps maxiimum bitrate. It produces higher quality 1080p video but for highest reliability, I'd recommend using fast Class 6 or Class 10 SD cards.
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Thanks.
I don't get it...
I don't get it...
I'm sorry, I'm not getting all of this: do you mean that the 44Mbps maximum bitrate patch is the most reliable 1080p patch, but the 55Mbps maxiimum bitrate produces higher quality 1080p video but has some flaws? If so, what are they?
Sorry for not getting it.
I don't get it...
I'm sorry, I'm not getting all of this: do you mean that the 44Mbps maximum bitrate patch is the most reliable 1080p patch, but the 55Mbps maxiimum bitrate produces higher quality 1080p video but has some flaws? If so, what are they?
Sorry for not getting it.
I found this chart quite helpful:
http://media.bestofmicro.com/F/F/178107/original/sdhc-transfer-write.png
in all the excitement, i totally forgot about the mjpeg filesize limit!
total noob mistake that almost tripped me up on an interview shoot today. i flipped over to 60p avchd and kept on rolling. =)
lpowell:
now i'm even more happy with your latest patch! (i have to shoot a lot of 30p)
back to transcoding again...
total noob mistake that almost tripped me up on an interview shoot today. i flipped over to 60p avchd and kept on rolling. =)
lpowell:
now i'm even more happy with your latest patch! (i have to shoot a lot of 30p)
back to transcoding again...
So Lpowell, with these new settings it should be possible to get really pristine 25P 720AVCHD that you can easily convert to 24P right?
Easily convert 25p to 24p you mean slowing down speed by 4.096 % or some convoluted frame blending ?
Regarding those higher bit rates with the AVCHD codec, it just frees some overhead in case of highly detailed scenes, which occur only under specific circumstances, right ? So it won't necessarily affect the average bitrate for everyday shooting. My question is : would there be any gain in quality if we could get higher bitrates under low detail, dim light conditions or is the codec already giving the best out of these poor conditions ? (I'm getting usually 6-8 Mb/s for this kind of shots, is this anormal ?) I'm asking this, knowing that it's an adaptive codec.
If there would be a gain, is low light bitrate a target of current hack development ? Don't mean to go out of topic, just trying to understand what these bitrates improvements mean to everyday use.
No frame blending. PAL to 24P has been done for a long time. 4 percent is pretty imperceptible.
So, the updated ptool allows this patch to work on NTSC and PAL. I can understand using a GOP length of 3 for the 720p30 in NTSC, but what does this do with 720p25 in PAL? 25 is not divisible by 3. Would it not be better to use a GOP length of 5, which works for both p25 and p30? I am not criticizing, but just trying to understand how this works. Thank you LPowell for your fantastic work!