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21

The default settings for ffmpeg are very low quality, and since you don't specify any codec or quality parameters it's just using the defaults (I don't know why the devs don't fix that because it generates a lot of questions on forums everywhere). Edit: the defaults are now quite sane. With a recent build of ffmpeg you don't need to specify anything more ...


7

One of the bits of information associated with a H264 stream is its level. The level informs the decoder the computational resources needed for a successful decode. Turns out that the highest level 5.2 supports upto 9437184 luma samples per frame, which is the number of luma samples needed for a frame of size 4096x2304. So, there may be encoders that can (be ...


6

H.264/AVC is not limited for 4K in terms of max resolution as it supports DCI 4K (4092x2160) @ 60 fps at Level 5.2. For example Sony already uses XAVC which is exactly 4K AVC. For a while the max level was 5.1 and 5.2 was introduced later. If needed new levels can be introduced as long there's the hardware to support it. For eg. the Nvidia NVEC supports ...


5

Yes, if you record a video in 4K, then downsize to 1080p, the image will look much clearer than if you shot the video on a 1080p camera. You can also zoom in up to 200% and still retain the quality in a 1080p time line. Why it may look better is because most sensors these days use chroma subsampling. On most consumer 1080p video camera products, the camera ...


5

There are three key factors in your cameras low light performace: 1. Lens (Aperture) The lower your f-stop, the more light gets through to the sensor, you will also have a very shallow (narrow) Depth of Field. Often this is a requirement at night, since cutting off most of your light is generally a bad idea. When looking at any camera, see what lenses are ...


4

Look at it from a data rate point of view: a GH4 records 4K at 100 Mbps. A RED Carbon Fiber WEAPON records at 300MBps. That's 24x the data rate. Look at how very much more expensive it is to purchase a CPU that's 10% or 30% faster than "normal" and you might then have some understanding of how much more expensive it is to offer 10x or 30x the performance ...


4

First off, 2K is not 1440p, it is 2048 x 1080p. 4K is 4096 x 2160p. (Note that UHD = 3840 x 2160p...4K and UHD are like US and Canadian dollars--they are both dollars, but they have different values.) It's simple math: when you have a straight line and you make it twice as long, the new length is 2x the original length. When you have a rectangular area ...


4

According to Wikipedia ,Digital Cinema Initiatives originated the term 2K in 2002 for a digital film format of 2048 x 1080. 2048 is commonly referred to as 2K in the digital world. It logically follows that when DCI went on to specify a resolution 2x larger in each direction, they called the 4096 x 2160 format 4K. 4096 is commonly referred to as 4K in the ...


4

Both files that don't play feature Opus as the audio codec. As per this site, Opus is not one of the supported audio codecs. Transcode the audio: ffmpeg -i in.mkv -c:v copy out.mkv


3

There's apparently a hack which alters the Vegas executable to solve this problem. There's a setting of dpiAware in the application manifest which falsely tells Windows that Vegas is DPI aware and will scale up text and icons on a HiDPI display. Vegas does not do this. So, the value should be changed from true to false. The hack tutorial alongwith link to ...


3

The minute you said "no lighting" you violate the premise of "look as professional as it could be and not too amateur". Lighting is not only about ensuring there are enough photons to actually record decent image on the camera's sensor. Lighting defines highlights and shadows, contrast ranges, areas of focus and mystery, etc. It is almost impossible to ...


3

Changing the preference doesn't change any clip settings retroactively. But once you have set it, and then create a new project and a new sequence, and when you freshly import your 4K clip and drop that freshly imported clip onto your freshly created sequence in your freshly created project, it should work as you expect. And if you right click on the clip, ...


3

The key to pulling a good key is a clean separation between key and subject. All things being equal, higher resolution will give a sharper edge between key and subject, which is good. But that's just one consideration. Chroma subsampling is another. Chroma recorded at full bandwidth (at least 10-bits and 4:4:4) will give a cleaner key than chroma ...


3

As mentioned by @Mulvya, I think the issue is the "slow" preset. One option is encoding a compressed stream that is also lossless. For example, the x264 encoder can do this using "-preset ultrafast -qp 0". This will probably result in failing your 3rd requirement (compatibility), but since it's lossless, you can transcode later onto cheap spinning disks. ...


3

Judge based on the quality rather than the bitrate value. Use CRF mode encoding and if the quality isn't what you can accept, decrease the CRF value. ffmpeg -i "%%a" -s 3840x2610 -c:v libx264 -crf 18 -acodec copy D:\%%~na.mp4


3

You are probably comparing cameras that record compressed 4k video with cameras that record uncompressed video, i.e. RAW footage. The ARRI ALEXA and RED Epic belong in the latter category. The hardware for cameras capable of recording RAW footage is more expensive. Also, it hasn't been around for as long and as with every new technology, prices start ...


3

In my opinion, the market for 4k delivery is still very small, but that doesn't mean its useless. Shooting at a higher resolution than the delivery resolution allows you to recompose shots without any quality loss. If you shoot a talking head in 4k but deliver in 720p, you can get a wide, medium, and closeup from the same shot. In my experience clients ...


3

Where are you planning on exhibiting the footage? In my experience, the average consumer has a low-quality TV they bought because of the price, and they have the factory settings that look awful because they don't even know that they would want to change them, let alone how that would happen. In my opinion you're wasting your time because your client ...


3

The reason for mastering out to an uncompressed / minimally lossy format is so that you have a master copy, which you can then use to make other copies, without generation loss, or having to re-render. You don't have to use Animation. There, I've said it. While it's mathematically lossless, it's only 8-bit, so swings ± roundabouts. While I used to only ever ...


3

To get from 1080p to 4K you're going to need to re-encode, but container won't matter (much), so 16bit png is overkill just for the sake of 4K. H.264 works fine. But before you spend the time to upsample, you should double-check to make sure that you actually need to. Most modern 4K televisions upsample 1080p on the fly. Most mobile devices aren't high ...


3

Yes, you can do this successfully. I did it with an overhead 4K action camera with a fixed fisheye lens (YouTube video here). You'll want to remove the distortion in software to "square it up". Then you have some room to zoom in and pan. However, you effectively lose some resolution with the lens correction. You can only zoom in so far before it's ...


2

We shot one of the first indie HD films back in the day when the prosumer HD cameras first came out. Because we were one of the first feature films to shoot in HD we secured a national theatrical release. If I was shooting a feature film today, I would do it in 4K. Because at some point in the near future theaters, NetFlix, Cable Networks, etc. will be ...


2

It all boils down to "Do you need it" If you are shooting corp promos and your clients keep asking or are insisting on 4K then Yes you can look into it as you can justify the purchase as the work is going to pay for it in the end. If it is just an odd job here and there that they want 4K then hire one as it will be much cheaper at £££/$$$ for a day or two ...


2

As you know there are two solutions, one using your CPU, the other a dedicated GPU. CPU Solution As of today, the CPU solution exit for 4K content, at 60 fps, using x265 or x264 codec. x264 is embededded in OBS in fact, and x264/x265 are known for being the fastest implementation of the standard H264/H265. But, you need a powerful CPU, of course, and then ...


2

Short answer: no, 4K down-scaled to 1080p is not necessarily going to give you a better result than filming with a FullHD camera. The SONY A7S is the hands-down best low-light video camera for less than $34,000. (The Panasonic Varicam S35 and the Alexa can shoot better images, albeit at much higher costs). Here's a surf video shot entirely by moonlight, ...


2

The image processing of cinema cameras is done with fairly inexpensive FPGA chips, that doesn't explain a 50.000€ price difference between I.e. a gh4 and a arri Alexa. The FPGA chip used in blackmagic products is sub 10€, so even if the Red or Alexa use a 100€ fpga, that's not the point. Media storage is also not the point, since all vendors use standard ...


2

In addition to the points above, keep in mind that cinema cameras also have a host of features not found in cell phones and lower-end cameras, such as removable lenses, better autofocus, better bodies that may be weather-resistant or weatherproof. They also have larger sensors which cost more, and the specs on the sensors are probably better than in low-end ...


2

I dug further and after reading the entire topic at Personal View, I found that user willyfan suggested to add in_range=full to both first scale arguments to correct a color shift that he also observed. And it works. So here is the full ffmpeg code, adapted from karl's script, for windows: ffmpeg -i "input.MP4" -filter_complex "extractplanes=y+u+v[y][u][v]; ...


2

Story Your film needs drama. That is normally created by conflict or tension. Keep the story simple. It is better for your first film to be too simple than too ambitious. But it must have drama. Shot list or story boards Work out what your film will look like before you shoot. You don't need to storyboard, but you need to know what shots you want before you ...


2

Yes, useful for wide crowd shots. Yes, you can crop down/scale up 1080p selections from the 4K to simulate additional camera angles. Consider using the gopro app or a wifi remote to stop/start the gopro so you don't have to physically access the device while monitoring your main camera(s). Not sure how long the event will run for but you might want to look ...


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