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8

You can use ffmpeg, a free command-line tool, to do this: ffmpeg -i input.mp4 -vf setpts=8*PTS -r 30 -crf 18 output.mp4 This slows down the video 8 times and output is 30 FPS.


6

At a certain time you can see the rocket at two places at the same time. What you are seeing has nothing to do with compression artifacts, but is frame-blending due to the slow motion effect applied (in the video) Let's say the video is recorded at 30 frames per second. You only have 30 'pictures' per second to capture the information. If you want to slow ...


6

There are methods to generate frames in between frames, mostly giving you mixed results. For one, the plugin "twixtor" (~330$) actually does a somewhat decent job at assuming missing frames, so much so, that a 30fps video can be played back at half the speed, making it look like 60fps slow-mo. On the other hand side, you can sample the frames directly in ...


5

This requires a repetitive motion and good lighting. You expose the position of the droplet on successive oscillation, but capture it at a slightly different spot on each. Thinking about it from the perspective of a ball bouncing. On the first photo, I take a quick photo of the ball on the ground. The ball bounces up and then back down. I then take a ...


5

The reason we try to shoot at our target frame rate is because if we need to adjust the frame rate, the computer has to invent new frames to go in between our existing frames. This can result in artifacts in the image and generally reduces the quality. You are correct that 24fps is the standard for theater and also correct that you need to shoot a faster ...


4

I figured out the problem. My shutter speed was set too low. Turns out it needs to be double the frame rate in order to achieve a smooth motion when interpreted to 24 fps. Should have thought of that before I shot. Oh well. Lesson learned.


4

While it is true that 720p video only has about half the data of a 1080p feed, the other thing you have to realize is that when you push the system beyond it's limit, it may spend a lot of time trying to process frames that it doesn't finish in time. Depending on how the player is configured, it may give up and try to catch up rather than finish rendering ...


3

By shooting at higher frame rate, you can achieve great looking and frame accurate slow motion. Interpolation is not going to happen. But if you want to slow down your footage beyond the frames you have, you can use the right tools in your video editor, or Twixtor plugin, but of course it will not give you as good results as a dedicated high speed camera. ...


3

You only need to overcrank the scenes you want to slow down in post. Editing and effects software make it easy to decimate from 60 (or higher) to 24 fps. You'll get better flexibility if you shoot your slomo scenes at a the highest exact multiple of the base rate that still gives acceptable exposure etc. So 96, 120 or 240 fps would be preferable if they work ...


3

There are a few things to consider. The MP4 spec was not designed for the playback of high frame rate files, because the files are highly compressed, and limited to using a single core for decompression. Even if you had 12 cores, the file would not decompress any faster. The easiest way to solve your issue is to either encode the MP4 into another codec, or ...


3

You may want to look into Sony's camcorder line (even legacy; like the NX5U). The NX5U and I think even the FX1000 (which is an HDV Tape Format and can be had used on a place like ebay for under $1000) could do bursts of full 1080p 240+ for a "limited time". If I remember correctly the FX1000 by sony could do 240 frames at for 10 seconds. It would buffer ...


3

There isn't really any magic bullet in high speed photography. High speed photography is difficult because of the amount of data involved and the sensitivity necessary for the sensor. Both of these factors combine to drive up the cost of all portions of the camera to do it well. You can either sacrifice quality (which the iPhone does) or you can sacrifice ...


2

You should be safe setting playback rate at 0.400. 59.94 is actually 60/1.001 and 23.976 is actually 24/1.001, so the 0.4 multiplier is technically exact. Switch off resample to be sure. Of course, how Vegas actually handles this internally is anybody's guess. One way to test this would be to generate a frame sequence just containing an incremental numeral ...


2

As 50ndr33 says, you need to shoot/capture at as high an FPS as possible. The more FPS the better the slow motion effect afterwards. Kronos is also a great plugin, but as he also states - it has some problems when footage isn't linear. If that's the case, you should have look at Twixtor. It's a bit more advanced (and more expensive) but it's better at ...


2

If you shot at 120fps, it is presumably to get a slow motion effect. So the playback actually needs to be at your normal 24/25/30 fps speed to get the effect. There is no such thing as 120 fps playback. The maximum I know of would be 60p. What do ffmpeg or mediainfo report as the frame rate for these videos. If they report 120fps or some other weird value, ...


2

I think you're out of luck. Official specs say 30fps max, and I can't find any documentation of a possible hack. http://www.nikonusa.com/en/Nikon-Products/Product/Digital-SLR-Cameras/25478/D5100.html The most widely distributed slow-mo camera is probably the iPhone 5s-- I bet you could borrow one to play around with.


2

If I read this right, you want to watch your 120fps videos at 0.25 their real speed, seeing every single frame but at 30fps. That's what I do (GoPro 3+, 720p, 120fps) but it's a bit involved. I use Blender video sequence editor. It's not intuitive but a good tutorial can make all the difference in the world, I learned with Mikeycal Meyers' tutorial: ...


2

This type of problem is usually a side effect of the type of compression used. In order to minimise the bandwidth requirements, frames are simplified, reusing content from previous frames etc. And this can cause interesting video effects when key (whole) frames are corrupted or missed.


2

To answer your Questions in order: You can see the framerate of a clip or sequence by navigating to the metadata panel. It's usually one of the tabs in the upper left on the standard layout. If you don't see it, select Window -> Metadata. Generally, you should set sequences to match you source material. So if your camera records 720p @ 60 fps, stick to that....


2

Just like with any effect property you can animate it by clicking on the little stop watch on the left of the effect property name (see below). You can apply the effect to just a single clip, you don't have to use it on the entire sequence, just drag and drop the effect from the effect list onto the desired clip and then animate the speed of the video via ...


2

You can do it by adding transitions between the speed changed clips as described in the documentation section titled Add Transitions Between Speed Segments. They say: When two adjacent speed segments are set to play at different speeds, you can control how smoothly the video switches between the playback speeds. When there’s no transition between the ...


2

Depending on how much you are looking to slow down. Interpret as 50fps, and then once in your timeline, say it is a 25fps timeline. Then you can stretch the footage using time remapping, then you can turn on frame blending to the solid line...this will be good in most instances up to about 25% speed of original... Less than that the same, 25fps timeline, ...


2

You can use the Time Remapping effect, and just use keyframes to ease in/out of different speeds. https://helpx.adobe.com/premiere-pro/using/duration-speed.html


2

Based on all info, it looks like the difference occurs with FFmpeg's internal MPEG-4 part 2 encoder, whose use can be identified by the string mpeg4 (native) after the 2nd arrow in Stream #0:0 -> #0:0 (mpeg4 (native) -> mpeg4 (native)). If you use libxvid which is a third-party MPEG-4 part 2 encoder, the error does not occur. My guess is that the ...


2

In theory, if the number of keyframes and their placement were about the same, as decided by the encoder, then yes, you can reduce the bitrate to half and retain the same quality. In practice, the encoder may be configured to place a keyframe every N seconds, in which case, you should use a bitrate a bit higher than half the original bitrate, say, around 55%....


2

Here's the gist of the ffmpeg method: use the blackframe filter to identify frames with a certain amount of non-black content. Use the metadata filter to pass through those frames and discard the rest. Inspection: ffmpeg -i in.mp4 -vf blackframe=amount=0:threshold=92 -f null - The amount (0) in the blackframe parameters refers to the percentage of pixels ...


1

Looks like you will need to transcode all clips with frame rates not matching the project's frame rate: If the frame rate is of a clip is not compatible with your project, it displays in red. You will be unable to import the clip into your project. Clips with incompatible frame rates may be playable in a new project set to the same frame rate as ...


1

Since this has worked with Canon footage in the past, my best suggestion would be to import your a7s footage into a 59.94 fps sequence in Premiere, export that sequence (in 59.94) in a universal format like H.264, then re-import that clip to Premiere and try slowing it down to 23.976. My guess is that Premiere isn't playing nice with whatever codec/format ...


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