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Crusade on MJPEG hacks
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  • I have to give my subjective opinion in this debate. Looking at your night test EOSHD i've to say that the 'look' of the mjpeg is exactly what i'm searching for. I find it really film looking. I notice and i recognize that the avchd codec gives more details, less noise, less banding, but i see to much microcontrast, blacks are too black, edges are to... edgy, i don't know how to explain. What i really wish is a codec, probably the avchd, that has also the qualities of the mjpeg. I hope that the research on quantization can lead to these results.
  • My main point is numerous more MJPEG patches with different E quality / table settings will not lead us to better MJPEG and they are a distraction, a bad testing approach.

    Multiple MJPEG patches are also confusing for majority of actual shooters.

    I thought the MJPEG PTools settings as they are now are known quantities. They're ported from the GH1 and we understand what they deliver and where the limits are. But we keep seeing MJPEG patches with yet another claim to fame, if it's not reliable, then it's very reliable, and now it's great in low light when it isn't.

    If we want to improve the GH2's low light performance we will not be able to do it via constant tweaking of E quality / table settings. It is a dead end and a waste of valuable testing effort.

    Happy to end my crusade here really. I've shown what I wanted with the test above, and probably pissed a lot of MJPEG patch fans off at the same time!!

    MJPEG can be useful in future for:

    4:3 if we can get true resolution, not upscaled VGA
    Motion and keying with action shots
    Maybe higher than 1080p resolutions

    None of these can happen via the tweaking of bitrates.

    I cannot see how the latest MJPEG patch 'low light' is any different to the last one anyway in terms of image quality. I can appreciate some shooters may like the look of MJPEG as it is now despite it being technically inferior to AVCHD and 24p being so much more cinematic to 95% of people.

    I want to see meaningful MJPEG research but this will not be done by this line of testing so please no more MJPEG patches with slightly different bitrates but wild claims to fame.
  • ughhh, you still don't get it andrew and you say everyone else is blind . I fully understand why you wouldn't want to spend your time on mjpeg lowlight and I'm actually with you, I don't care for mjpeg really and I can achieve it's look in post. But it's plain insulting to the intelligence of other people when you say it's a "total brand exercise and useless". You say: " I don't like to see people waste their time on something that's so obviously as flawed a concept as 'an MJPEG low light patch'." I'm sorry, but who promoted you to our time rescuer hero? I and only I will decide on my time distribution, and frankly, since I make a living on video production etc, I think I'm qualified to make an artistic decision that might involve not choosing avchd in lowlight (" If you shoot in low light at high ISOs on the GH2 stick to AVCHD, period"). About the whole business concerning your EOSHD anamorphic guidebook, I'll tell you why it came up. A brand new thread on the GH2 hack which gives you an extra option, worthless or not, and you attack it calling it a total brand exercise, now that's personal, and so there were personal answers to that about your own, rather epitomized, "brand exercise". Simple really.

    I'll talk no more about this, since hopefully I explained some stuff for you

    to end this I'll quote your own words: " there's enough room in a world of 6 billion for different philosophies and approaches to one's perspective on life, and each person has more than one!"
    enough said!

    Stefanos
  • @stefanos
    You can discuss MJPEG as hard as you want, but don't go personal.
  • @stefanos
    Please continue to debate with me but do address the issue, not me. It isn't a personal crusade it is a suggestion, a firm opinion. The issue is the tweaking of E1, E2, table, quality, and calling it 'low light patch'. It is not a new patch, it is the same as the last one but with a different label. It doesn't give us anything new, it doesn't lead to anything new. You can put E1 quality to 400, 500, 600, 700 it doesn't change the fact that AVCHD is better in low light, it just encourages people to waste time and to shoot with the wrong settings in low light. Those with an artistic need for 30p and more noise - fine, no problem with that at all. But it is not really the point here. The goal is to improve the low light performance of the GH2 and also if possible do research that leads to better MJPEG. Just huffling bitrate again and again doesn't do that. I see through my site that the multitude of MJPEG quality / bitrate patches are simply a distraction for people who want to use the hack in their projects as early as possible. I also reckon that it gains so much attention it's a distraction from more meaningful testing. How about a brute force coordinated approach to AVCHD low / high numbers in the latest PTools instead? That has the potential for better low light if I am not mistaken. I am not saying everyone should suddenly stop MJPEG research all I am doing is stating an opinion. Feel free to ignore it if you want, but be mature enough not to suddenly think I am some kind of kitten murderer or something. You should define people by meeting them not by their opinions on a forum.
  • @stefanos
    Please stop this Lpowell vs Andrew thing.
    If debate is over, do not post :-)
  • @Vitaliy_Kiselev
    fair enough, I finished what I had to say with the comment I just posted, why was it deleted so easily? It wasn't inappropriate or anything, the opposite it was somewhat constructive. Unfortunately, Powel's topic became flame and thus it was moved here, so that people's views wouldn't be misrepresented.... Anyway
  • @stefanos
    It had been deleted because I warned you, see my post above, and it contained almost nothing about topic title, MJPEG settings.
    Personal fights don't bring anything useful, especially if they are pointless.
  • topic title is "EOSHD crusade... on MJPEG hacks" :) if it was named "MJPEG HACKS" we wouldn't even be discussing this right now
  • >topic title is "EOSHD crusade... on MJPEG hacks" :)

    Yeah, nothing in it is about stefanos crusade on EOSHD :-)
  • sorry, but I love both modes in low light,
    if I want a little more "Filmgrain" I use MJPEG,
    what's wrong?
  • I think one important point is that (and not only in the MJPEG department), people are "testing" known capabilities of the hack with the goal of finding good looking end-user settings. As far as I can tell, this is not the best way of testing things, and is only muddying the useful test results.

    First the firmware, encoder, etc. must be exhaustively explored and understood via systematic testing (with a little less regard for what will look amazing in the end).

    Once the limits of what can be done with patching/hacking are found, then the hunt for the optimum combination should begin.

    That's my 2cents. I'm no GH2 tester, but I've had plenty of experience with tech problem solving, and a systematic approach has always seemed to work best, combined with an occasional break to try some crazy outside of the box stuff.

    As I'm not a tester, I'm not going to bother the testers or even patch my camera until the testing has settled down into a more finalized state, and I'm not going to ask questions about the patch, because this takes precious time away from Vitaliy and the testers.
  • EOSHD: "It is not a new patch, it is the same as the last one but with a different label."

    Actually, I was surprised to discover that my old GH1 MJPEG patches did not produce the same expected results on the GH2. That tipped me off to the fact that the GH2 has far more potential for high bitrate optimization than the GH1 was capable of handling reliably. In addition, an even more useful capability of the GH2's MJPEG encoder emerged: the potential for engineering a remarkably consistent and predictable bitrate across nearly the entire useable exposure range. This was something I was never able to achieve on the GH1.

    While such subtle refinements in encoder performance may not be perceptible to EOSHD, the thing that particularly appeals to me about the GH2 is the opportunity it offers to explore optimization aspects more complex than the straightforward pursuit of maximum bitrate. With the GH2, 100Mbps is not the pinnacle of performance it was for the GH1, it's more like a reference standard of mainstream GH2 performance that will be useful for comparatively evaluating the capabilities of future patches to come. What was truly exciting about crafting this patch was realizing that optimization of the GH2 is literally starting at the point where the GH1 reached its limits.
  • I am not on a crusade against MJPEG per-see it's that I just don't think 99 combinations of bitrate tweaks to the same settings that have been around since the GH1 are going to get us very far.

    Some people think image quality and bitrate are exponentially linked somehow. They're not. There is no point pushing beyond 100Mbps when you still have 8bit, 4-2-0, 720p upscaled with moire, and just 30p. In fact you'd really need a magnifying glass to see the difference between MJPEG 30Mbit and 100Mbit as it is. I just think it's the wrong thing to focus effort on, that's all, nothing personal.

    How about some research into the 4MP burst mode at 40fps and seeing if the MJPEG codec can be used to capture a feed with the sensor mode in 4MP stills burst mode... Now that would be a step forward.
  • EOSHD: "I just don't think 99 combinations of bitrate tweaks to the same settings that have been around since the GH1 are going to get us very far."

    Actually, there's only one MJPEG patch that I recommend for the GH2:

    100Mbps GH2 Low Light MJPEG 1080p Patch
    http://www.personal-view.com/talks/discussion/479/100mbps-gh2-low-light-mjpeg-1080p-patch#Item_47

    As I mentioned above, MJPEG patches that were optimized for the GH1 do not work as intended on the GH2. While there's no harm in trying out GH1 patches as a starting point, they are unlikely to produce optimal results without further testing and evaluation on the GH2.
  • >How about some research into the 4MP burst mode at 40fps zed seeing if the MJPEG codec can be used to capture a feed with the sensor mode in 4MP stills burst mode... Now that would be a step forward.

    I would also be interested to know if Vitaliy has been able to see anything about that mode in his low-level GH2 exploration (not for more 4MP pictures burst but for less, better quality silent shutter stills)
  • "How about some research into the 4MP burst mode at 40fps and seeing if the MJPEG codec can be used to capture a feed with the sensor mode in 4MP stills burst mode... Now that would be a step forward."

    Andrew, why don't YOU get to work on that instead of making everyone feel like crap here. Come back when you have something new to add and at that point enlighten us!
  • Also, your continuous 720p reference shows you haven't been researching this much. You're right, on the GH1, 1080 MJPEG was just an uprezzed 720. On the GH2 it's not, it's better than that.

    Do YOUR research on this subject and then bring it to the table.
  • MJPEG will be with us for a long time. Stable high bitrate MJPEG settings will help out MJPEG based anamorphic settings and built-in timelapse setting... until AVCHD supports 422, Xfps, and custom dimensions. The argument about having so many confusing MJPEG settings is a moot point where we are going to see at least a half dozen different short GOP settings. Diversification is not a complete waste of time. e.g. The short GOP topic started small. It became a separate topic, and nobody trashed it. It is thriving now. Hat tips to those hard working people who kept the hope of short GOP alive. Of course none of them saying anything bad about high bitrate MJPEG. This is becoming a respectable community. But there's always a troll where good things are happening. Same old same old...
  • Well put stonebat. Please keep testing!
  • So emotional. Who's attacking MJPEG or the hack? I am fucking sick and tired of you guys blowing stuff up into a shit storm. If you can't be rational then go somewhere else.
  • As for the claim that patched MJPEG frame sizes (on either GH1 or GH2) are literally resampled from a 1280x720 frame, I still maintain that this is an unproven speculation.

    While MJPEG 1080p videos tend to look less sharp than AVCHD 1080p, that does not prove that they were in fact upscaled from a lower resolution image. Since Panasonic has chosen not to reveal the algorithms it uses to produce video frames from the high-resolution Bayer Filter raw data output of the image sensor, we may never know for certain how it's actually done. However, if a second stage of upscaling was inserted after a fixed-size 1280x720 frame was generated, that should produce telltale periodic irregularities in the width of finely-detailed diagonal lines in a test image. To date, I have seen no tangible evidence of any type of rescaling artifact of this sort in any MJPEG video.

    In all G-series cameras, the MJPEG encoder is required to generate not just a single HD 1280x720 frame, but multiple WVGA, VGA, and QVGA resolutions and aspect ratios as well. In addition, the MJPEG encoder is evidently flexible enough to work with a variety of image sensor scanning modes and sizes, ranging from 12-16 megapixels. Given these diverse requirements, I think it more likely that the encoder uses a single general-purpose scaling module capable of being programmed (or patched) to produce any specified frame size from the scanned image sensor aspect ratio. In any case, that is effectively how the MJPEG width and height patches work in practice.
  • LPowell, I experimented with one of your GH2 1080p MJPEG clips, and there is indeed more detail than 720p can resolve. I came to this conclusion by downscaling a screenshot of 1080p MJPEG to 720p, and upscaling it back to 1080p. Comparing the before and after, it's clear that there IS more detail and fidelity (not much, though), and the picture seems smoother (less aliasing) to me. But, the camera can't be just simply upscaling the 720p image as there wouldn't be any extra detail, whereas there actually is.
  • I hear you @LPowell

    At least 480p MJPEG seems much improved with the latest PTools. Before (with previous release) it looked like VGA mode simply upscaled. Now it looks like the actual scaling resolution 1:1. What has been changed to enable this Vitaliy?