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Ask Slashdot: Is There An Open Source Tool Measuring The Sharpness of Streaming Video?
dryriver asks:
Is there an open source video analysis tool available that can take a folder full of video captures (e.g. news, sports, movies, music videos, TV shows), analyze the video frames in those captures, and put a hard number on how optically sharp, on average, the digital video provided by any given digital TV or streaming service is?
If such a tool exists, it could be of great use in shaming paid video content delivery services that promise proper "1080 HD" or "4K UHD" quality content, but deliver video that is actually Youtube quality or worse. With such a tool, people could channel-hop across their digital TV service's various offerings for an hour or so, capture the video stream to harddisk, and then have an "average optical sharpness score" for that service calculated that can be shared with others and published online, possibly shaming the content provider -- satellite TV providers in particular -- into upping their bitrate if the score turns out to be atrociously low for that service....
People in many countries -- particularly developing countries -- cough up hard cash to sign up for various satellite TV, digital TV, streaming video and similar services, only to then find that the bitrate, compression quality and optical sharpness of the video content delivered isn't too great at all. At a time when 4K UHD content is available in some countries, many satellite TV and streaming video services in many different countries do not even deliver properly sharp and well-defined 1080 HD video to their customers, even though the content quality advertised before signing up is very much "crystal clear 1080 HD High-Definition".
What's the solution? Leave your thoughts and suggestions in the comments.
And is there an open source tool measuring the sharpness of streaming video?
If such a tool exists, it could be of great use in shaming paid video content delivery services that promise proper "1080 HD" or "4K UHD" quality content, but deliver video that is actually Youtube quality or worse. With such a tool, people could channel-hop across their digital TV service's various offerings for an hour or so, capture the video stream to harddisk, and then have an "average optical sharpness score" for that service calculated that can be shared with others and published online, possibly shaming the content provider -- satellite TV providers in particular -- into upping their bitrate if the score turns out to be atrociously low for that service....
People in many countries -- particularly developing countries -- cough up hard cash to sign up for various satellite TV, digital TV, streaming video and similar services, only to then find that the bitrate, compression quality and optical sharpness of the video content delivered isn't too great at all. At a time when 4K UHD content is available in some countries, many satellite TV and streaming video services in many different countries do not even deliver properly sharp and well-defined 1080 HD video to their customers, even though the content quality advertised before signing up is very much "crystal clear 1080 HD High-Definition".
What's the solution? Leave your thoughts and suggestions in the comments.
And is there an open source tool measuring the sharpness of streaming video?
If you need a tool to tell, does it really matter?
There's already a metric that basically defines video sharpness: bitrate.
The sharpness of H.264 and H.265 is very well known. Since commercial streaming services use commercial streaming video codecs, it's a pretty safe bet that you can almost directly correlate resolution to bitrate.
There's virtually no incentive for streaming companies to deliver lower resolutions at higher bitrates. It would be a technical challenge to deliver higher resolutions at higher bitrates.
Therefore, bitrate is most likely the simplest and most accurate measure of streaming video sharpness.
sounds pretty simple to me: submitter has amassed a ton of pirated media with many duplicates. now they want an automated means of choosing the highest quality files (bit rate and/or resolution alone won't necessarily do that) from those dupes so they can trash the rest.
Sharpening the image is an inherently lossy process. You're replacing a more detailed image containing a soft edge with something that has a crisp edge with less gradation. You can't then reverse the process to get back to the original image, since there'd be no way to tell the difference between things that actually had a sharp edge in the original image and things that had merely had their edges sharpened after the fact. They'd both look the same.
Frankly, sharpness is a really lousy measure for determining how good an image is. It doesn't make images look better, in and of itself, and it's something that the user can already introduce themselves if that's where their preferences lie, simply by bumping up the sharpness on their TV. Of course, if your goal is to have the highest fidelity image, you shouldn't set your TV's sharpness to anything over 0. Back in the day of analog CRTs it used to be the case that sharpness might improve the fidelity, but ever since the switch to digital LCDs anything more than 0 adds sharpness that wasn't there in the original image, thus decreasing the visual fidelity of the resulting image.