Personal View site logo
Make sure to join PV on Telegram or Facebook! Perfect to keep up with community on your smartphone.
GH1: 75Mbps Peak Reliability Setting - V2 update
  • 75Mbps peak bitrate combined with high reliability @ 50/60 fps

    At the time the original 75Mbps GH1 Peak Performance Patch was released, I along with many other patch developers had reluctantly concluded that a stable Native 24/25p video mode could not be perfected for the GH1. It was not long after, however, that I discovered new stabilization techniques that led to the development of the Blackout-Powell Native 24p Patch and the Max Latitude Native 24/25p Patch. More recently, with Vitaliy's release of PTool 3.56d, all previously unhackable versions of the GH1 have been liberated for use with freshly upgraded versions of my patches.

    The primary focus of recent patches has been the optimization of 1080p Native 24/25p FHD video modes. In order to achieve bitrates as high as 100Mbps, however, it was necessary to restrict the 720p SH video modes to 25p in PAL mode and 30p in NTSC mode. For 720p SH mode recorded at the standard 50/60p frame rates, the 75Mbps peak bitrate of the Peak Performance Patch remains the highest I've achieved. With the aid of new stabilization techniques provided in PTool 3.56d, I have been able to significantly improve the patch's high-bitrate reliability as well. Based on the comparison tests I've conducted, the stability of the updated 75Mbps GH1 Peak Reliability Patch is second only to that of my Reliable In-Camera Playback Patch.

    Here are short descriptions of the updated properties of this patch:

    75Mbps AVCHD 1280x720 SH mode @ 50/60 fps
    While the unhacked 720p50/60 SH video mode offers high frame rates, its low 17Mbps maximum bitrate and long-GOP frame compression hamper its ability to track fast-moving subjects. In 60p mode, this patch reduces the length of each GOP to 20 frames, producing 3 key-frames per second. In addition, the codec's 75Mbps peak bitrate allows it to encode a large amount of image detail into each key-frame. Compression efficiency remains high enough, however, to limit average bitrates to less than 50Mbps.

    75Mbps AVCHD Interlaced 1920x1080 FHD mode @ 24/25 fps
    For those who do not require Native 24/25p video files, this mode produces the highest quality images available from the GH1 in both 24p and 25p interlaced FHD video modes. Turbo-charged with a 75Mbps maximum bitrate, the codec's ability to track moving objects without producing mud is significantly improved. As with the 75Mbps SH patch, the FHD encoder maintains an average bitrate no higher than 50Mbps.

    75Mbps MJPEG 4:2:2 Color 1536x864 HD mode @ 30 fps
    The MJPEG Intra-frame codec's unique advantage is its ability to produce highly detailed images in 4:2:2 color depth. This is especially valuable in green-screen rotoscoping, where you want to use the highest chroma resolution available. To maximize its usefulness, I've increased the MJPEG frame size to 1536x864 pixels, while maintaining the camera's normal16:9 aspect ratio. This frame size is exactly 20% taller than SH 720p mode, and 80% as tall as FHD 1080p mode. While it is non-standard, the intermediate frame size allows you to either flexibly crop the edited frame down to 720p, or upsample it to 1080p with minimal loss of resolution. And at 75Mbps max, the MJPEG encoder maintains consistently higher bitrates than the AVCHD encoder, particularly in dimly lit situations.

    30Mbps MJPEG 960x720 VGA mode @ 30 fps
    This iPod-compatible video mode produces HD-resolution 960x720 videos in a standard 4:3 aspect ratio. Its bitrate averages around 30Mbps.

    Overall Patch Considerations
    While no GH1 patch can claim to be absolutely bulletproof, I have tested these settings in a wide variety of extreme circumstances. However, with bitrates as high as 75Mbps, the safety margin is inherently narrower than my Reliable In-Camera Playback Patch. This patch is designed and tested only for the fastest Class 10 SDHC cards currently available.

    Additional points of interest:

    * The 75Mbps Peak Reliability Patch is compatible with all hackable GH1 cameras, and is switchable between NTSC and PAL modes.

    * I recommend using the camera to format your SD at the start of each shoot, to guard against SD card memory fragmentation.

    * Peak bitrates are obtained only with well-lit, sharply-focused, highly-detailed subject matter. Average scenes will produce average bitrates.

    * High bitrate AVCHD videos may not play back reliably in-camera. The MJPEG videos produced by this patch will not be playable in-camera.

    * If shutter speed is set longer than the frame rate (e.g. slower than 1/60 at 60p), low-quality video files may be produced.

    * AVCHD 4GB file-spanning for long video takes may not work reliably at high bitrates. For reliable recording of takes longer than about 12 minutes, I recommend selecting the "H" video mode instead of "SH". This will produce average bitrates of about 28Mbps in 720p50/60 modes.

    * For extended recording times at moderate bitrates, selecting the "L" video mode instead of "SH" will produce bitrates comparable to the camera's unhacked SH video mode.

    * While AVCHD bitrates may drop to very low levels in extremely dark situations, this patch should continue to record even in total darkness.

    *** WARNING ***

    The 75Mbps Peak Reliability Patch will not work properly with previous versions of PTool. My thanks once again go to Vitaliy Kiselev, for his pioneering work on PTool, and to cbrandin for his invaluable Stream Parser tool.

    The best way to insure that you have the latest PTool release is to download it directly from the following link:

    Download PTool here:

    75Mbps Peak Reliability Patch Settings File:

    This zipped INI file can be used to apply complete patch settings to firmware loaded into PTool 3.56d. To use, unzip the INI file into the same folder as the PTool application. Launch PTool and load the firmware for GH1 v1.32. The settings contained in the INI file will automatically be installed in the "H" button at the bottom of the PTool main window.

    Note that with the following PTool Settings File, you may at any time re-install the original Panasonic GH1 v1.32 firmware into the camera. You may also copy each type of patched or original firmware to separate SD cards, and use them to quickly switch between patches as often as you like.
    LPowell - 75Mbps Peak Reliability Patch
  • 46 Replies sorted by
  • Thanks for your work.
  • Reliable 720p60 75Mbps!!! Thanks LPowell.
  • What i've been waiting for, onto it right now lpowell.

  • lpowell, just checked the Mjpeg E1, - E4 etc and the resulting video is only 30Mbps not 75Mbps. So it looks like it's standard setting.
    E1 Quality=225
    E1 Table=96
    E2 Quality=195
    E2 Table=48
    E3 Quality=170
    E3 Table=16
    E4 Quality=150
    E4 Table=4

    Should they not be ??

    E1 Quality=280
    E1 Table=4
    E2 Quality=250
    E2 Table=10
    E3 Quality=225
    E3 Table=24
    E4 Quality=200
    E4 Table=48
  • The MJPEG HD E1-4 settings in the first list above are correct, but as you noticed, they don't record at a 75Mbps bitrate. After increasing the HD frame size to 1536x864 in 4:2:2 color, I tested the patch using the settings in your second list. That worked fine for most scenes, but in extreme cases the bitrate can exceed 75Mbps and cause write-speed failures. The settings the patch currently uses can produce MJPEG HD bitrates over 60Mbps and I have not yet seen it break.

    I neglected to change the docs to reflect the actual 60Mbps MJPEG peak bitrate, but I'm interested to hear how the new patch works for you. If you feel it's too conservative, I may try to revise the settings to produce a bitrate closer to 75Mbps.

    Another patch that looks pretty much unbreakable is the PAL 720p50 SH mode. If this patch can survive your open seas expeditions I'll be very pleased!
  • Thanks for the confirmation re the Mjpeg mode, it is fine for what i use it for, low light events like the Kava Ceremony i did with 50mm 1.4 Canon FD and it plays back in camera. Also i did revert the resolution to 1280 x 720, this size suits me better.

    Now onto the AVCHD modes, i tested both NTSC and PAL with my sharpest lenses, 20mm pancake and 14 - 140 kit with Sandisc 30MB/s Extreme in some brutal high contrast outdoor scene that i've used in the past and the PAL SH 720p mode is unbreakable. I would go as far to say as reliable as the reliable patch and returned av bitrates 5 - 10Mps higher than it, but also smoother motion (lower GOP setting..26 vs 30 ..??). The NTSC SH 720p was not quite as reliable in the same scenario as above, with the occasional card error but importantly the clips were not lost, just the recording stopped (very significant) This only happened in full auto mode (focus, aperture, ISO). I could control this easily as i knew when it was going to happen, so i would just lock exposure but still run auto focus.

    I'm guessing the lower GOP in NTSC mode might be the difference in reliability here (GOP 25 vs the PAL GOP 26)
    (actually in your first post you say the GOP is 20 for NTSC, the INI file shows it as 25 may be a typo in your first post)

    For outdoor Run and Gun work, if slight aperture changes are not an issue, i would enable auto ISO, it greatly reduces any mud in shadows and dull areas that the extra bitrate can't fix. This results in, the bitrate staying almost constant as does the exposure so mud is further eliminated.

    Awesome result for the V2 75Mbps PAL SH 720p, it is a new standard and now replaces the reliable patch on one of my GH1's.

    Thank you Mr Powell.

    UPDATE - I also meant to include that i also did these tests with an ND filter attached so that my lenses were operating at their sharpest f stop. (makes the patch and result all the more impressive)
  • Us poor GH13 users are being lost in the wave of GH2 euphoria. Guess i'll just have to be part of it. Damn, another camera.. :-(
  • 75Mbps Peak Reliability Patch Settings File:
    the download link for this .ini-file is broken for me in Safari and in Firefox - please renew
  • I checked it in FireFox, all working ok.
  • After renewing the page 3 times in Firefox I got it working, too - thanks
  • Is there a significant drop in reliability if I use native 24p FHD with this patch?
  • @krxz This patch is not reliable with Native 24p checked. If Native 24p is what you want, I recommend the 100Mbps Max Latitude Patch:
  • Yeah, I came across that one too, will try it out sometime this weekend. One thing that got me confused though - why is it that for the 100Mbps patch the 720p60/50 is stripped down to 720p30/25 and the bitrates are much lower than the ones for Blackout and even High reliability patches? If I uncheck the 720p60->720p30 will it have any effect on the stability of FHD mode?
  • @krxz I think this is explained in the first post of this thread
  • oh geez, pardon my inattention, I totally must have skipped that paragraph or something.. :D
  • Moved my initial comment to the right thread.
  • Hi I tried this patch, but on my GH1 the bitrate stays at around <16mbit, and there is a lot of artifacts and mud. What am I doing wrong?

  • Wow! Just updated my old GH1 with this patch and I have never had this little banding and macroblocking in low light (see screen grab), although the bitrate is rather low (but on the other hand the shot is almost static, so this is perfect).

    Thanks a million for making my B-cam a rather brilliant one!

    1920 x 1080 - 2M
  • I just picked up my GH1 after about a year or so of using it. Is this the definitive GH1 patch for MJPG. I seem to remember that the 4.2.2 was pretty bloody good.

  • put this patch in my GF1 & won't go over 20mbits/sec in "SH" mode no matter what i'm filming..don't know what's going wrong...anyone help??...and what is FHD mode?

  • I'll be shooting with GH1 next week (PAL - 25p) and I'm interested in the 75Mbps Peak Reliability Settings ... seems like the 100mbits peak settings might be crashing in hi detailed scenes but it looks like this 75mbits settings do not work with 25p checked... Or can I shoot with this patch and 25p checked without crashing the recording?


  • @MarkV

    can I shoot with this patch and 25p checked without crashing the recording?

    Sorry, this patch was designed to support 720p50/60 modes and that required turning OFF the Native 24p/25p setting.

  • as I know this patch ( 75Mbps Peak Reliability Setting - V2 ) records only in interlaced mode in full hd, what you probably want is blackout-lpowell native 24/60p patch