Need to downsample video to a lower resolution


Increasing or upscaling video resolution, converting SD video to HD for instance, refers to scale up the video image to fill a HD format (always with high resolution). It increases more pixels, but the quality will not improve. Meanwhile, it will change video size to larger one. So a poor original video file (e.g. 320P) is ALWAYS going to get bad result after you change video resolution to HD or 4K. Whatever software you use, it MUST NOT reach your expected results. However, you might be satisfied with the final effect if you convert from 320P to 480P, 480P to 720P, 720P to 1080P, 1080P to 4K.

On the contrary, a huge demand also exists to reduce video resolution (aka downscale video resolution), such as downscale 4K to 1080P, 720P, 480P and so forth. Because the higher resolution means it needs higher configuration to run and more space to store. That's the reason someone always wants to convert 4K to 1080P, 1080P to...

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Hello guys!

Since me and many other people have been waiting for the glorious NVidia DSR feature to come to our mobile GPU's as well, I have thought that giving some info's about an alternative method would make some people happy.

So, during this last week, together with the release of Witcher 3, I have chosen to start playing Witcher 2 as I saw that the games are quite related and the story is continued in each game (in comparison with many other games which don't have that continuity inside the story ). Since Witcher 2 was released in 2012 I was looking for different methods to boost the graphics to the maximum in order to further enjoy the landscapes and all the elements of the game. I was also looking for something different from the Ubersampling option which is still a power hungry feature that kneels my GTX 980m (Yeah... a freaking 2012 game can kneel a high end GPU from 2014 with just an aliasing option).

Since Ubersampling was thought as a more aggressive...

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08-12-2013, 09:28 PM

(This post was last modified: 08-12-2013, 09:42 PM by neobrain.)

Posts: 104
Threads: 7
Joined: Jun 2013

Hi guys, you don't have a 4k Monitor like me?

wanna test how your Nvidia card really perform at real highest resolution?

Go to Nvidia Control Panel and
Create a Custom Resolution:
Horizontal pixels: 3840, Vertical lines: 2160, Refresh Rate: 60,
Timing: Manual, Active Pixels: 1920/1080, Front porch: 20/3, Sync width: 20/4,
Total pixels: 2004/1092, Polarity: Negative/Positive.

until the test worked, you need to go to Customize and make sure, that the 3840x2160 resolution is checked

Super Smash Bros Brawl - Dx11 with highest AAx8 samples (Quality 32x) @4k Resolution with a GTX 780 Windforce overclocked (Gpu clock : 72+mhz, Mem clock: +400mhz)
on very highest demanding level on brawl still 92FPS

Do it on your...

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I'm not intimately familiar with CoreImage or image processing in Swift/iOS in general, but let me try to give you at least a starting point.

A raw image (mosaiced image) is essentially a one-channel image, where different pixels correspond to different colors. A common layout may look like:


Note that in this arrangement (which is common for most mosaiced files, with notable exceptions), each 2x2 pixel group repeats across the image. For the purposes of resizing, these 2x2 regions can be considered as superpixels.

I'm assuming you have access to pixel data of your image buffer, either from a file or from memory.

The simplest way to efficiently generate a lower resolution RAW image will be to downsample the image by an integer factor. To do so, you would simply take every nth superpixel along rows and columns to form a new RAW image.

However, this operation can cause image artifacts such as Aliasing to appear in your...

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With so many cameras now shooting 4K a lot of people have computers that will struggle to edit the footage. However, editing 4k footage on a low-spec computer is still possible with a little workaround. We explain how.

We’ve all been there at some point. You try to edit a video on your computer only to find it skips and jumps, making it virtually impossible to edit with any real finesse. Obviously the ideal solution is to splash the cash and buy a new computer, but that isn’t always possible. Or it could be that you want to edit 4k video on your laptop whilst on the go, but it simply isn’t powerful enough.

Thankfully there is a way you can still edit 4k footage, or any other high resolution video, on a computer that is underpowered.

In this article I’ll explain how I am able to edit 4k video on a 2011 Apple Macbook Air.

Editing 4K: The Basics

If you can’t edit 4k footage properly then you can always use proxy files and offline editing. Not sure...

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I applied this and it works great, and While it does not work out of the box on newer drivers, You can install 12.11 catalyst, set this up, remove them, install 13.5 and it still has the 2650x1440 option there above my native 1080p.

You cannot change it back however until you go back to 12.11 again. Application Does not work after 12.11, yet the data saved is still there for the driver change.

While people do not like the desktop (1080p) displaying 1440p as it looks shit, then put your Desktop back to 1080p, and just have your games @ 1440p

Tested Hawken, Tombraider, Sleeping Dogs, Trackmania United & War Thunder, they all work at 2560x1440p

The performance hit is there, so right now I'm selective with what I want to look better @ 1440p or keep it set to native 1080p, whether I have the performance headroom to enable a higher resolution or if the game in question has NO AA filters and I'd like to have the downsampling working in my favour...

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In this article, I want to share with you how to downsample 4K smartphone footage to create great-looking 1080p with minimal chroma sampling artefacts.

For any of you who follow me on social media or have seen my YouTube channel, you’ll know that I shoot a fair amount of video with my iPhone SE and iPhone 7 Plus. I color grade in Resolve as I would any other source footage, and the results have surprised me enough to keep me experimenting and pushing what can be done with well-exposed, well-shot video from a smartphone. These devices, along with the FiLMiC Pro app, continue to fascinate and impress me. I want to share as much of my findings as possible, and this is one of my techniques.

It’s known and accepted that down-scaling from a higher source resolution (such as UHD to HD) produces better looking, sharper, cleaner results when compared to footage originated natively at that resolution. There are many reasons for this, and the results differ depending on...

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Since the digital era begun, video quality has been continually improving over the years. However, a better quality most of the times means bigger file sizes, and that can be extremely inconvenient when we want to upload and share our files on Youtube, for instance, or we begin running out of disk space. If you wonder how you can compress a video to reduce its file size, without losing in quality, then you are in the right place.

When do we need to compress a video?

As we mentioned, with the rise of social media and streaming services, videos are everywhere, along with other multimedia as well.

Most of the times, though, we want to upload videos as fast as possible, so we want high internet speeds. At lower speeds, it could take us a very long time to upload a video we shot, of - let’s say - 2GB.

In such cases, we need to compress the video as much as we can,...

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Printer resolution is measured in ink dots per inch, also known as dpi. Generally, the more dots per inch, the finer the printed output you’ll get. Most inkjet printers have a resolution of approximately 720 to 2880 dpi. (Technically, inkjet printers produce a microscopic spray of ink, not actual dots like imagesetters or laser printers.)

Printer resolution is different from, but related to image resolution. To print a high quality photo on an inkjet printer, an image resolution of at least 220 ppi should provide good results.

Screen frequency is the number of printer dots or halftone cells per inch used to print grayscale images or color separations. Also known as screen ruling or line screen, screen frequency is measured in lines per inch (lpi)—or lines of cells per inch in a halftone screen. The higher the resolution of the output device, the finer (higher) a screen ruling you can use.

The relationship between image resolution and screen frequency determines...

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Low compression (high quality) JPEG

High compression (low quality) JPEG

In information technology, lossy compression or irreversible compression is the class of data encoding methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size for storage, handling, and transmitting content. Different versions of the photo of the cat above show how higher degrees of approximation create coarser images as more details are removed. This is opposed to lossless data compression (reversible data compression) which does not degrade the data. The amount of data reduction possible using lossy compression is much higher than through lossless techniques.

Well-designed lossy compression technology often reduces file sizes significantly before degradation is noticed by the end-user. Even when noticeable by the user, further data reduction may be desirable (e.g., for real-time communication, to reduce...

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I have been encountering questions about sample rates and bit depth a lot recently and been looking into the topic in the past week. I have been reading different articles around the web and browsing forums like Gearslutz to try and develop some sort of understanding of the general consensus in the field at the moment.

So let me share with you where I stand on this right now. Now, I am not a very techy person so please feel free to correct me if my assumptions are wrong, and please share your thoughts. Let us continue the discussion in the comments.

Please note: Since writing the original article I have learned a lot – not least from you guys – so thank you very much for your comments and pointing me in the right direction! I have updated this article to reflect my current views on August the 10th 2014.

What Sample Rate to Use?

So what’s the fuss – why wouldn’t you just go as high as your setup allows? First of all it takes up a lot more resources from...

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But you can repeat this lesson until you’re blue in the newspaper column, and some people still won’t believe you. They still worry that their 5-megapixel camera from 2005 is obsolete. They still feel sales pressure when shopping for new cameras.

So as the host of a TV series (“It’s All Geek to Me,” to begin in April on Discovery HD and the Science Channel), I thought I finally had a chance to settle this thing once and for all. At the climax of the camera episode, I would test the Megapixel Myth on camera, supplying visual proof for the world to see.

I created three versions of the same photograph, showing a cute baby with spiky hair in a rowboat. One was a 5-megapixel shot, one was 8 megapixels and one was 13.

I asked 291 Digital, a New York graphic imaging company whose clients...

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Nvidia CEO Jen-Hsun Huang loves a spectacle. So while you’re reading this sentence, the GPU-manufacturer’s founder is regaling thousands of gamers at a 24-hour gaming event the company is sponsoring in Los Angeles with the announcement of Nvidia’s latest graphics processor, code-named “Big Maxwell.”

Despite Nvidia’s draconian efforts to prevent a recurrence of the leaks that presaged the announcement of its Shield Tablet, details of the new GPUs have been dripping into the Interwebs for several weeks. Here’s the official information: The new GPU will initially be available in two SKUs, the $329 GeForce GTX 970 and the $549 GeForce GTX 980. The GTX 970 has 1664 processor cores running at a base frequency of 1050MHz (boost clock of 1178MHz), while the beefier GTX 980 has 2048 cores running at 1126MHz (boost clock of 1216MHz). The GTX 970 and the GTX 980 both have a 256-bit interface to 4GB of GDDR5 memory running at an effective speed of 7Gbps.

The mounting brackets on...

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