Can anybody shed some light?
I've been shooting video for some time with my D3s (just casually, my real work is all stills) and have always been extremely impressed.
This weekend, on a whim I pointed the camera at my kids playing in the backyard and recorded a couple of minutes of video.
It was a sunny day and I had the camera in auto exposure and tripod mode, 720p quality. Picture mode Standard.
When I looked at the video on my computer it looked awful. Severe jpeg compression blocks everywhere. Completely unwatchable.
Does anyone know what might cause this? Could the camera's video mode be malfunctioning? I have never seen this before.
D3s Video Problems(33 posts) (15 voices)
Can anybody shed some light?
What type/speed is the card you were using?
The CF cards (both of them) are Lexar UDMA 8GB.Never had a problem with these before with either video or stills.
Sorry Buggy can't help, never experienced anything like that. Have you rung your local Nikon service centre and run it past them? They would be my first port of call (well maybe after asking the forum)! :-) Hope you get it worked out, and be sure to let us know what the problem was if you do.
Next stop - Nikon Dealer.
I'll let you all know the result.
Thanks for the input.
Can you post the video?
You'll have to excuse my ignorance here, I'm new to this... How do I post a video?
If you have it online like youtube or vimeo, then post the link like this: http://www.youtube.com/jkoncepz#p/u/28/hQwuzVY5mCA
this is one that i shot in low light at a club.
I looked back at some of my other footage and have noticed that there is some jpeg noise, particularly in the fringe edge between a focused subject and its out of focus surroundings.
The large jpeg blocks appear strongest in the out of focus areas of slow movement, e.g. out of focus tree branches and leaves gently blowing in the wind.
Under certain lighting conditions it seems very apparent. In the case above the subjects were backlit, outdoors with the sun behind them. It was shot from a distance with a 50mm lens 25+ feet from the subjects.
I also notice that close ups tend to look much better.
I'm working on uploading a sample video.
Primitive motion JPEG codec, compression artifacts?
What kind of computer (specs,RAM, video card, etc.) are you using? Are you doing any editing or is the video straight out of the D3? What program are you using to download the video?
Computer is a new MacBook Pro 2GHz i7 with HD display, 8GB Ram, 500GB HD 7200RPM, AMD Radeon. Running Snow Leopard 10.6.7
The video is unedited, simply transferred the file(s) from the Nikon's CF card via card reader to my Mac and double click. I've tried Quick Time Player and VLC, quality is the same.
What are your camera settings? It still sounds like a software issue to me. Have you tried a hard reset of your D3?
It could be the Mac not having the correct codec. Try using Nikon software that came with the camera to bring the video into the computer.
wish buggy would let us know what was the solution to the problem
Sorry for my absence everyone... I'm just back from a summer traveling.
I appreciate all of the input. I have shot loads of video since and sometimes it looks great and occasionally it looks horrible.
Here's a link to some that looks horrible: http://www.flickr.com/x/t/0097009/photos/beautifytheworld/5718713627/
It appears that flickr has compressed it on the upload making it look even worse but the stuff straight out of the camera (on this occasion) doesn't look that much better.
This was imported form the CF card into Lightroom 2. I have since tried Nikon's import software and there's no improvement.
I don't shoot video commercially, just stills, so this isn't a hugely pressing concern but I am curious if my camera a has a glitch or not.
Thanks again for the input.
Hi! this is my first post and will give my opinion-
The sample looked good to me. i viewed it on my Mac Pro and saw very minor artifacting, but only when panning in your shot. What could be the issue is that if you are looking at QT files, be sure you have the right codec to view the file. Every video camera format file is different in some regards. Be it Sony, Panasonic, Canon , Red One, Phantom, or in this case Nikon.
I would go to the Apple site and see if there is a codec plug in for Nikon video format (for QT). Also, check with Nikon as well to see if there is also a QT plug in for there software as well.
It could also be a compression issue as mentioned earlier. After about a minute or two, the CPU on the camera may lag, causing artifacting, and thus, choppy video, gliphs, unexplained nonsense. I have seen this with numerous productions of the Canon 5d and 7d. It just doesn't hold up. In other words, the camera is meant to be a still camera and not a substitute for a real video camera. Just doesn't have the umph to move it along.
720p native will look a bit jittery when viewed in a 1080i environment. I see it on TV alot. But your sample is passable in most cases.
I hope my input helped.
Thanks Photomatt, very helpful input indeed.
I am going to do a few tests to try and understand under what circumstances the artifacting is most noticeable as some of my videos look great to me while others don't look like they were even shot with the same camera.
I will report back to the group with my findings.
I am experiencing the same problem with my D3s. I bought it to learn and get introduced into Filmmaking, so that is very important to me. However, I find a lot of videos, especially in the background, have a lot of grain, even outdoor in places one would consider to have great lighting conditions.
I'm stumped on this one. It seems to depend greatly on the position of the sun while shooting outside. If shooting with the sun behind your subject, things with detail like grass seem to have a lot of noise and artifacting.
Even slight over-exposure results in a very visible mosaic pattern of JPEG artifacts.
Shooting with the sun behind you seems to result in much smoother images.
This is not definitive. Just something I noticed this past weekend and will do more testing on. Aperture and shutter speed may also play a role in this... TBA
What's really frustrating is that none of this seems to be consistent. Sometimes the videos look really fantastic, smooth and cinematic while other videos taken under similar circumstances look awful with very significant compression noise (those irritating visible blocks that move slower than the overall image, the type you see on cheap/poorly encoded DVD's).
More to come...
I hadn't seen this thread before.
Looking at the back-yard video you linked in a previous comment the answer is simple: The encoder is bit-starved.
That is a very difficult scene to encode, between the fractal detailed vegetation and the chain link fence at a spatial frequency just above the AA filter it is a wonder you don't get more macroblocking (a better term than "JPEG artifacts" if you're talking to tech support or googling).
I have not paid much attention to video on Nikon DSLRs, but just looking at this video I'd assume the D3s has a much lower maximum bitrate than the D7000 (being on the bleeding edge of Nikon video)? Is this right? More bitrate would solve this problem fast, a more efficient codec would help*, but this is classic bit starvation.
*The more efficient codecs are more efficient for two key reasons:
1 - Better compression of dependent frame deltas
2 - Better use of perceptual techniques, shifting bits from where humans don't see them to where humans do.
The artifacting in this video appears to be present in the Independent frames as well (as I'm not seeing obvious "snap" at keyframes, if you really care you can post the original video somewhere and I'll take a look) - a place better codecs aren't better. Unless the D3s uses MJPEG. Does the D3s use MJPEG? In that case anything would help, more bits, better codec with any motion prediction yadda yadda yadda. MJPEG is a dog.
That's great feedback... thanks!
I'm pretty sure the D3s does in fact use MJPEG encoding as it was one of Nikon's first attempts at adding video to a full frame DSLR. But at what point in the process can I make an improvement? Wouldn't it require a firmware update from Nikon?
I will post the original video file online once I establish a place to do that... Stay tuned!
Buggy said: But at what point in the process can I make an improvement? Wouldn't it require a firmware update from Nikon?
It would not only require a firmware update, but possibly a hardware one. :(
How can you avoid it? Reduce detail in your movies? ;)
Macroblock based codecs spend the majority of their bits on the definition of edges and high contrast lines. MPEG (2, or 4) saves bits by storing frame N just like a jpeg, but frame N+1 as the difference between N and the predicted N+1. MJPEG can not do this. This makes it less than half as efficient.
Look at the file size of a JPEG of well-focused grass vs the same quality setting JPEG taken of the sky. The grass image will be MUCH larger. All Nikon digital cameras encode JPEGS in what's known as CQ mode - constant quality. User defines the quality and filesize (bitrate) will vary to accomplish that.
Due to bandwidth limitations your D3s is likely encoding the video in either CBR (constant bitrate (quality varies based on content but size is constant)) or ABR (average bitrate, which should be thought of as a constrained CQ mode). Either way macroblocking is the inevitable result of not enough bits to encode scenes with lots of fine detail.
I really don't think your video looks that bad, but will reserve final until I can see the original. As I said this looks like bit starvation, only two answers - increase bitrate (likely can't) or decrease complexity. Even holding the camera still will dramatically decrease bitrate needs (though less with MJPEG than MPEG).
I finally uploaded some original video here: https://files.me.com/mrorganic/mhes9r.mov
I locked down the camera and recorded (more or less) the same scene. Again, look closely at the flat, wood surface of the kids climber.
This camera can produce some beautiful video, but the 'macroblocking'(thanks for the term) in this file and others like it really do leave me scratching my head how anyone could rely on it for professional (read consistent) video production.
Thanks again for all of the great feedback!
BuggyPosted 4 years ago #
Something's wrong with your last video link? I get a binary dump.Posted 4 years ago #
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