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5

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). Try adding -c:v libx264 -crf 20 -preset slow to the command. -c:v libx264 tells it to use the libx264 ...


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 ...


4

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 ...


4

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 ...


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

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


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

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 ...


1

I have a Blackmagic Design DeckLink card which, with bundled software, provides live keying. I bought that card before they sold a DeckLink 4K cards. But because they come withe the same bundled software and make the same live-keying claims, I would check that this version first: https://www.blackmagicdesign.com/products/decklink/techspecs/W-DLK-04 You ...


1

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 ...


1

Based on this illustration, you are able to compare the sensor sizes of red cameras with film formats like 16mm, 35mm or 70mm imax and so on.


1

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, ...


1

As I understand it, ffmpeg creates a raw image buffer with the input files it is given, then applies effects such as scaling and then encodes. So if you use ffmpeg to do the scaling and encoding to a 4:4:4 codec it should do what you want: ffmpeg -i "my_gh4_422_4k.mov" -vf scale=1920:1080 -c:v prores -profile:v 4 -c:a copy "my_prores_444_1080.mov" It ...



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