How do I enhance/correct waterfall footage?

[Canon GL-2 Guy]

Waterfalls, gushing streams and other moving water

This past weekend I took a brief trip to New Hampshire's White Mountains. I took some footage of the Crystal Cascades which is beautiful and majestic to behold in this part of the world. HDV 1080 60i . This was my initial foray into nature with my Canon A1s.

I have very little experience in shooting this type of content and plan to shoot more like it just as soon as possible in that region. I need to learn how to maximize results and output.

Upon viewing, import and playback, I quickly noticed the following:

Granted the water was chaotic in places, flowing at a high rate and somewhat torrential however I saw jagged and sharp lines jumping all over the place which significantly impacted on the quality.

Bottom line: it looks too ragged/rough. My goal is to have the footage be more orderly and smoother.

Is what I'm seeing interlacing or another type of problem?

Is there possibly a camera setting that would improve things next time out?

How do I successfully address the above and correct this to the extent possible?

Thank you.

[jagabo]

Basically, you're screwed. The camera compresses too much for that type of video. But, just to be sure, upload a small sample.

[Canon GL-2 Guy]

Direct, blunt, to the point and not exactly encouraging.

Are you telling me waterfalls, rivers and streams all yield the same general result?

Would "30F"/30p be any better?

What are the rules and limitations for uploading video which I've never done?

[TreeTops]

Did you use a tripod when you did the vid of the falls?

[jagabo]

High compression codecs like h.264 rely on the fact that most video doesn't change a lot from frame to frame. Basically, they can just say "this frame is the same as the last one, just change these small areas. Large chaotic changes like splashing water, flames and smoke, flickering lights, etc. kill that type of compression.

30p may be slightly better than 30i (now called 60i by marketing droids) because progressive frames are a little easier to compress than interlaced frames.

You can upload up to 30MB clips directly to this web site. For larger clips you can use any of the file transfer sites like Mediafire.com, MegaUpload.com, Rapidshare.com...

[Canon GL-2 Guy]

Yes,

Even though there was a safety wall in the main falls viewing area/vantage point , my 60" tripod barely made it over the tip which was awkward.

Also, I shot in other locations where there was no wall.

I would never shoot without a pod because my hands are so shaky!

[Canon GL-2 Guy]

Could I convert the clips to 30p or in Canon A1s speak: "30F"? If so, how is that done?

Would shooting in AVCHD potentially produce better results?

The format of the A1s I believe is .m2t not h.264.

Could the clips be uncompressed somehow to improve the quality or is it too late?

Sorry, if some of these questions are ignorant!

[diprotic]

Could I convert the clips to 30p or in Canon A1s speak: "30F"? If so, how is that done?

Would shooting in AVCHD potentially produce better results?

The format of the A1s I believe is .m2t not h.264.

Could the clips be uncompressed somehow to improve the quality or is it too late?

Sorry, if some of these questions are ignorant!

You could very easily deinterlace your "60i" stream to 30p, but that wouldn't do much to improve quality.

You can't "uncompress" frames once they're encoded. Some enhancements are possible using filters and such, but don't hold out hope for a massive improvement. The GIGO (garbage in, garbage out) principle applies in most cases.

If you've done any still photography, you know how labor-intensive retouching an overexposed or blurred frame can get. But, video is much harder to correct, since you're "retouching" 30 pictures for every second of footage!

I haven't shot in HDV (uses mpeg2) or AVCHD (uses h.264), but the wikipedia article on AVCHD indicates that it may work better than HDV.

For high-motion shots, I would use whatever settings allow for the highest possible bitrate. I also don't recommend using interlacing, it's a legacy setting; all newer TVs and equipment work best with progressive frames.

The process of producing high-quality video is a time-consuming, labor-intensive process of trial-and-error. I suggest taking video of the same subject matter with different settings, different lighting, etc. The best settings will vary with your circumstances.

[aedipuss]

HDV is 25mbps mpeg-2. you should be able to get very decent footage of your nature shots if there is good lighting and a tripod. i always shoot 30p with my HDV cam. it is always possible to interlace it later for dvd output but getting decent output from de-interlacing 60i for progressive video or display on a computer monitor is almost impossible. to watch your footage on your monitor in as best a form as you can, use vlc and set the de-interlacer to yadif(2x).

that cam of your should produce near film like quality.

[jagabo]

Ah, OK, it's an HDV camcorder. So you have MPEG 2 video. You could try running a deblocking filter on the video files. That will replace blocky artifacts with slimy (smooth gradients) artifacts. You may find the latter less offensive. A while back I posted an example of deblocking:

https://forum.videohelp.com/threads/337748-How-to-encode-xvid-with-h-263?p=2100735&view...=1#post2100735
https://forum.videohelp.com/threads/332303-Removing-jagged-interlacing-artifacts-from-a...=1#post2061689
https://forum.videohelp.com/threads/337748-How-to-encode-xvid-with-h-263?p=2101241&view...=1#post2101241

Be sure to view the images at full size. Those were overcompressed Xvid videos with Xvid's built in deblocking filter, and MPEG 2 with DgMpegDec's deblocking filter. You might try the latter. Or any of the AviSynth deblocking filters. Be sure you're running using an interlaced aware deblocker when the source is interlaced.

[edDV]

Some camera techniques to try. These work better with a tripod to minimize full picture camera shake. Full frame shake (also unnecessary pans or zooms) chew up bit rate. Camera stabilization allows most bit rate to be directed to the moving water.

1. Shoot the stream/river from the top or bottom rather than the side. This decreases the apparent motion and allows one to play with lens depth of field (e.g. defocusing the foreground or background or both).

2. Decrease the shutter speed to about 1/30th (experiment). This will smooth the motion over the duration of the frame. When you fix a slow shutter speed, this causes the auto iris to close more. This in turn widens the depth of field restricting the ability to defocus parts of the scene. In overcast weather, you will have a greater usable range for iris. You can force a more open iris using neutral density filters in brighter weather. In fact with camcorders neutral density filters become your iris (depth of field) control.

3. You can also experiment with 30p or even 24p frame rate for low motion shots. For fast water motion (like a side shot) these settings will cause jerky motion due to slow frame update. Again, neutral density filters will allow more manual exposure and depth of field control in bright light. For example, shooting a white water raft in spring runoff will appear jerky using 24p or 30p vs 60i. If you need progressive, you would bob deinterlace 60i to 60p or let the HDTV do the bob.

All of this needs experimentation. Shoot the same water scene at different shutter speeds and various combinations of auto iris using neutral density filters. You won't see much difference in the low res camera LCD. You need to take a large monitor with you or study the differences in the motel or when you get home. A typical movie set will have a high quality CRT monitor in a tent to study different camera exposures or focus effects.

[aedipuss]

i just don't get why people claim 30p is jerky. 24p film speed was chosen because the human eye/brain perceives it and any frame rate above it as smooth.

[Canon GL-2 Guy]

One of the strongpoint of still photograpy is the capability to slow down the motion in order to obtain the classic silky smooth, ribbon-like flow! Changing a shutter speed from say 1/60 to an 1/10th of a second is enough to achieve a nice looking shot.
I also shot with a D-90 at the same site.

Unfortunately, time was not on my side as my wife and I had to move on to the next sight seeing stop, so the opportunity for experimentation was very limited.

I was hoping there was a video equivalent! This discussion has been very informative and interesting.

[jagabo]

24p film speed was chosen because the human eye/brain perceives it and any frame rate above it as smooth.

No, it was chosen because it's the lowest frame rate you can tollerate. It's still jerky. Even 30p is obviously jerky and flickery. If your monitor runs at 60 fps watch clip in this post:

https://forum.videohelp.com/threads/307004-Best-framerate-conversion-%28eg-23-97-to-30-...=1#post1888926

[davexnet]

That's a good demo jagabo. How can 24 fps film source ever look that smooth on an LCD ?
No matter how many times you repeat each frame, there's still only the 24 that are unique.

[jagabo]

How can 24 fps film source ever look that smooth on an LCD ?

It can't (not without motion interpolation, which has its own problems). But the high contrast in those animations was chose specifically because it accentuates the problem. The problem is less visible in shots with less less contrast. And when you add in motion blur or depth of field blur it becomes even less visible. But you can see this problem any time there is high contrast, medium speed motion in film based sources.

[aedipuss]

24p film speed was chosen because the human eye/brain perceives it and any frame rate above it as smooth.

No, it was chosen because it's the lowest frame rate you can tollerate. It's still jerky. Even 30p is obviously jerky and flickery. If your monitor runs at 60 fps watch clip in this post:

https://forum.videohelp.com/threads/307004-Best-framerate-conversion-%28eg-23-97-to-30-...=1#post1888926

you really think all movies in theaters are jerky? i guess i prefer the "jerky" look of 30p to the blurry look of motion in 30i.

[jagabo]

you really think all movies in theaters are jerky?

Yes. You can see it any time there's a bright panning shot.

i guess i prefer the "jerky" look of 30p to the blurry look of motion in 30i.

There's nothing inherently blurry about 30i.

I bet if we had a 100 year history of 60 fps film, and somebody tried to introduce 24 fps film as a new innovation, he would be laughed out of the theater for the jerky mess.

[aedipuss]

wikipedia -

The human eye and its brain interface, the human visual system, can process 10 to 12 separate images per second, perceiving them individually. The visual cortex holds onto one image for about one-fifteenth of a second, so if another image is received during that period an illusion of continuity is created, allowing a sequence of still images to give the impression of smooth motion.

guess you're just not human

[jagabo]

wikipedia -

The human eye and its brain interface, the human visual system, can process 10 to 12 separate images per second, perceiving them individually. The visual cortex holds onto one image for about one-fifteenth of a second, so if another image is received during that period an illusion of continuity is created, allowing a sequence of still images to give the impression of smooth motion.

guess you're just not human

Did you look at the video I linked to? Did you see a difference in smoothness between the 30p and 60p rows? Case closed.

[aedipuss]

There's nothing inherently blurry about 30i.

all movement in 30i is blurry, the 2 fields of the single frame were taken at different times. when you put 2 pieces back together to view a frame anything moving is blurry and distorted even on an interlaced tv.

[poisondeathray]

There's nothing inherently blurry about 30i.

all movement in 30i is blurry, the 2 fields of the single frame were taken at different times. when you put 2 pieces back together to view a frame anything moving is blurry and distorted even on an interlaced tv.

Possibly distorted from aliasing, but not necessarily blurry. If you blend deinterlace , then yes it will be blurry.


Anyone recall the "48 FPS" topic that James Cameron advocated? It's funny, he now things 60 FPS is the ideal now - for marketing reasons.

We are just so accustomed to 24 FPS cinema, that any theatrical production looks plain weird IMO at anything else

I am now leaning toward 60 frames mostly because of broadcast," he said. "Broadcast is already at 60. We can't tell people going to the movie theater that you're going to see less. Now that we have surfaced this idea of frame rates into the public consciousness and into the discourse, we can't tell people they are seeing less in a movie theater than they are seeing in their home. And they're seeing 60 right now in their home. Sports broadcasts are 60i (interlaced) moving to 60p (progressive) in the next year. We can't appear to be noncompetitive.

http://www.variety.com/article/VR1118043598?categoryid=3996&cs=1&cmpid=RSS|News|Latest...medium=twitter

[jagabo]

There's nothing inherently blurry about 30i.

all movement in 30i is blurry, the 2 fields of the single frame were taken at different times. when you put 2 pieces back together to view a frame anything moving is blurry and distorted even on an interlaced tv.

No. You see one field at a time on an interlaced TV. The two fields have no effect on each other. Of course, you have only half the vertical resolution in each field. Obviously, 60p is preferable to 30i from a viewing perspective.

[edDV]

There's nothing inherently blurry about 30i.

all movement in 30i is blurry, the 2 fields of the single frame were taken at different times. when you put 2 pieces back together to view a frame anything moving is blurry and distorted even on an interlaced tv.

That is not due to 30i/60i (same thing) , that is due to poor deinterlace in your computer player or display. You want to avoid 60i to 30p conversion, especially with blend deinterlace.

In VLC or MPCHC you can spec Yadif deinterlace for 30i/60i to 60p and the motion is smoother. In theory 60i is twice as motion smooth as 30p.

HDTV sets vary in processor sophistication but modern sets, even most Vizios do a credible 60i to 60p conversion. My Sony Blu-Ray player does an excellent deinterlace job. I've posted before, I'll dig them up.


Note. Even edit software and the pros have ditched 29.97 interlace terminology in favor of "60i". "60i" does describe the motion issue. Formally, 60i means 59.94 fields per second. 60p means 59.94 progressive frames per second.

[aedipuss]

no it's not. 30i/60i is blurry because the 2 separate parts of a frame are shot at different times. anything that moved is no longer aligned. the odd and even fields alternate having been recorded separately causing blurring. to some the blurring may look like motion but it's not.

[aedipuss]

There's nothing inherently blurry about 30i.

all movement in 30i is blurry, the 2 fields of the single frame were taken at different times. when you put 2 pieces back together to view a frame anything moving is blurry and distorted even on an interlaced tv.

No. You see one field at a time on an interlaced TV. The two fields have no effect on each other. Of course, you have only half the vertical resolution in each field. Obviously, 60p is preferable to 30i from a viewing perspective.

an interlaced tv refreshes every other line(or field) alternately. so yes your brain combines them back into a frame because of persistence.

wikipedia

Such scan of every second line is called interlacing. A field is an image that contains only half of the lines needed to make a complete picture. The afterglow of the phosphor of CRTs, in combination with the persistence of vision results in two fields being perceived as a continuous image, which allows the viewing of full horizontal detail with the same bandwidth that would be required for a full progressive scan but with twice the perceived frame rate and with the necessary CRT refresh rate to prevent flicker. Interlacing is used by all the analogue broadcast television systems in current use

[jagabo]

an interlaced tv refreshes every other line(or field) alternately. so yes your brain combines them back into a frame because of persistence.

wikipedia

Such scan of every second line is called interlacing. A field is an image that contains only half of the lines needed to make a complete picture. The afterglow of the phosphor of CRTs, in combination with the persistence of vision results in two fields being perceived as a continuous image, which allows the viewing of full horizontal detail with the same bandwidth that would be required for a full progressive scan but with twice the perceived frame rate and with the necessary CRT refresh rate to prevent flicker. Interlacing is used by all the analogue broadcast television systems in current use

Then 60p would be blurry too. And the real world, at effectively infinite fps, would be even blurrier.

[edDV]

There's nothing inherently blurry about 30i.

all movement in 30i is blurry, the 2 fields of the single frame were taken at different times. when you put 2 pieces back together to view a frame anything moving is blurry and distorted even on an interlaced tv.

No. You see one field at a time on an interlaced TV. The two fields have no effect on each other. Of course, you have only half the vertical resolution in each field. Obviously, 60p is preferable to 30i from a viewing perspective.

an interlaced tv refreshes every other line(or field) alternately. so yes your brain combines them back into a frame because of persistence.

wikipedia

Such scan of every second line is called interlacing. A field is an image that contains only half of the lines needed to make a complete picture. The afterglow of the phosphor of CRTs, in combination with the persistence of vision results in two fields being perceived as a continuous image, which allows the viewing of full horizontal detail with the same bandwidth that would be required for a full progressive scan but with twice the perceived frame rate and with the necessary CRT refresh rate to prevent flicker. Interlacing is used by all the analogue broadcast television systems in current use

An interlace CRT TV first shows field one then field two. Each contains half the vertical resolution and the field rate is 59.94 (or 50 for PAL). True the brain resolves most of the vertical resolution (about 75% on a still per Kell factor). The eye/brain does not resolve full H or V resolution for a moving image. Instead it interprets shapes and direction (similar to objects and motion vectors). The eye/brain is fine tuned to motion smoothness. Jerky motion rarely happens in nature and is disturbing.

A progressive monitor shows full frames in succession rather than fields. If the source is 59.94p (50p) such as 1920x1080 60p or 1280x720 60p, then all the advantages of interlace are preserved plus the eye/brain resolves more vertical resolution during low motion. If instead you display progressive video at half frame rate 30p (25p), a certain degree of less natural motion jerkiness is introduced. This is most noticeable during low to medium motion where the eye/brain is still trying to resolve detail such as during a slow pan/zoom or say arm movement while the camera is stable.

"Hollywood" standardized film frame rates to 24p in the 1930s when audio was added. Before that frame rate was an option for the director. Low motion could be under-cranked to save film stock. The projectionist would attempt to match frame rate at the projector. Sound required a steady frame rate. 60p would have been ideal but Hollywood was not prepared to eat that film cost during the Depression. Instead they tested the minimum frame rate the public would accept and that was 24p.

24p has many limitations and is very jerky when a simple hand held camera is used. Even with stable tripods, pans or zooms produce very stepped motion except at a few optimal rates discovered by research. Even a locked 24p camera presents other issues.

Take a scene where two actors are conversing. Any motion in the background such as a car or pedestrian passing will be stepped in motion. Our eye/brain is drawn to any unnatural motion. Hollywood covers this defect with short depth of field lenses to blur out background motion*. But short depth of field lenses are very difficult to maintain focus on the actors. This requires detailed direction of actor movement and even a second camera operator called a focus puller to maintain focus. Hollywood can handle 24p with these and other techniques because they are on a controlled set. 24p does not work well for shooting natural motion where 60p (50p) is more ideal. If you shoot 30p, you have these same issues of motion steppiness.

In the above, I'm comparing a pure interlace system to a pure progressive. I'm skipping over the issues with progressive vs interlace transmission, or display of interlace source on a progressive display.



* they also do this to optimize MPeg compression.

[Canon GL-2 Guy]

Gents:

I think my thread has been officially hijacked!

Enjoy yourselves.

[edDV]

Gents:

I think my thread has been officially hijacked!

Enjoy yourselves.

It all applies to you and your XH-A1.