My head is about to explode...
Is the following reasonable ( if one takes a loose approach to the mathematical functions)
FPS x Resolution
-------------------------- = Required Bitrate
Compression
I have some videos which I want to play on a particular TV, but the TV is revolting. I think too high demands are being placed upon it somewhere.
In reality I think it is audio demands causing it to screw up, but the struggle of trying to understand that has resulted in me also trying to understand the impact various factors have on resource demands and file size.
I should get a job, the struggle of understanding this stuff is killing me. You'd almost think I hadn't spend some years being a broadcast consultant.
Last edited by: VxFan on Thu 5 Sep 19 at 10:16
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Much as I appreciate the effort, please don't Google it. I can do that, and indeed have done. A lot.
I am hoping someone can give me a less scientific and more easily relatable explanation.
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Late here.... I'll think tomorrow.
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Perhaps it might help if you expand on "TV is revolting"
What does that mean?
blank screen? drop outs? freezes? artefacts? With a TV the actual symptom really often points to the issue, TVs are quite fixed in their ways, quite dumb when it comes to video processing, and can often only result in a small range of issues, unlike PCs which can display a multitude of different types issues.
Last edited by: Zero on Wed 17 Oct 18 at 07:20
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Does the TV actually work when connected to a different source?
Freeview, VHS/DVD player or whatever?
How are you connecting to the TV? Scart, HDMI, or are you using a memory stick plugged into a USB socket, etc etc
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I think I wasn't clear so let me re-explain.
The TV is just fine and working in every way it should. It just won't play certain video files. These are .mkv files, which as I'm sure you know is a container that may hold a wide range of stuff. Some [most] it will play, a few it will not. I think the audio is tripping up the codec in the Samsung [spit] TV, though I have yet to be sure.
I can convert the files easily, but in order to maintain the same parameters it takes a 100mb mkv and turns it into, for example, a 3GB mp4. With the number of files concerned that is a major issue.
The purpose for my question is to understand the interaction between FPS, resolution, bitrate and compression ratio and their respective and differing impacts on the viewing quality. Then I can sort out what I should be converting these to so that they work, which is easy enough, but don't provide a file the size of a small planet simply to have acceptable quality. Nor do I want to noticably lose quality.
I don't want to have to try each file and see if it works, there are many files, from many different sources and only about 1:10 fails. I want to convert the whole lot in one go to something acceptable without needing to check each individual file, which is a pain.
Don't get hung up on the TV. It is both fine and largely irrelevant. It is the interplay of the various parameters and the type and quality of file that they generate that interests me.
Out of interest insofar as the error is concerned, the TV simply gives a codec error and will not even attempt to play the file. The error message is not meaningful.
Last edited by: No FM2R on Wed 17 Oct 18 at 10:46
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I know you said don't Google, but I wonder if you've looked at the documentation for a product you perhaps don't use?
I had a similar query a couple of days ago, and found the tenchical documentation for Handbrake (a product I do use) to be fairly comprehensive in explaining the interaction of all the factors.
You might find some dregs of utility in it.
Scroll down about halfway to find the technical links.
handbrake.fr/docs/en/latest/table-of-contents.html
Sorry if this no good to you.
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Just off on the school run so can't read it in detail, but actually it looks useful, thank you.
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Having just reread, perhaps have a look at the "anamorphic" section first, where it explains "resolution" and how that actually appears on the screen.
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While I can't really help with the OP query, I can recommend Handbrake. It has a batch mode, and I've frequently used it to switch mode of videos to something my phone would play. I usually struggle to kick off the batch mode first time as it's not intuitive but only because I'm not a frequent user.
It does take a while to convert but that is probably to be expected. I think it's processor grunt it needs. You can set up custom setting and save for future use. It'd be worth reviewing at least one movie in some detail to make sure it's good though.
Last edited by: smokie on Wed 17 Oct 18 at 12:38
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Good man Crankcase (and Smokie for the confirming recommendation), Handbrake led me to my answer showing me the information differently than I had seen when I'd looked at the files before.
I'm sure most of you don't care, but FWIW here are the details;
A file that works on my TV is using H.264 compression whereas a file that does not uses H.265.
H.265 is a newer, and far superior, compression standard but anything much older than this year will have H.264 codecs. H.265 file and an H.264 codec can fail anywhere, but is often the audio.
Aside from requiring a different codec H.265 also murders batteries on phones and requires much greater processing abilities in televisions.
I have two seemingly similar videos except that;
H.264 720x404 display, 542kbps data, 201mb file
H.265 1280x720 display, 2168kbps data, 142mb file
To convert the H.265 file to H.264 whilst maintaining the same display size/resolution & bitrate generates a 1.5GB file.
So now I have an easy way to detect a file which will fail, which is great because I simply did not want to go through over a thousand files one by one.
Reducing the display to 720*404 and the bit rate to 768kbps gets me down to a 263mb file but with a noticeable degradation in Frame Rate.
So I need to play with all three parameters together whereas my current tool only lets me play with Bit rate and Resolution.
I have downloaded and need to learn enough about Handbrake to get the frame rate up without getting an astronomic file size. No doubt it's easy to do, but I'm on a learning curve.
Thanks for the help.
Last edited by: No FM2R on Wed 17 Oct 18 at 13:46
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What did we find out?
Wondershare Video Converter is ok, but not worth paying for
AnyVideo Converter is ok and free.
But best seemingly are;
Handbrake is good, not very intuitive but will do what you want, pretty slow and free
MediaInfo is a great little app for finding out all the details of your files, bit techie, and free.
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You can do this to Handbrake, which might give a small percentage speed increase, at the expense of everything else of course.
ccm.net/faq/31435-handbrake-allocate-more-cpu-resources-to-the-conversion-processes
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Video files - No FM2R
