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What you need to know before touching a video file

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Re: What you need to know before touching a video file

#61

Post by wizhi »

swiftcoder wrote: post #42
gruez wrote: post #28

Earlier quoted context omitted.

>Really good quickstart guide It really isn't. You have to scroll 75% of the way through the document before you it tells you what to actually type in. Everything before (9000+ words) is just ranty exposition that might be relevant, but is hardly "quick".

Nah, see, I maintain a commercial video platform, and half the battle is people typing things in before they understand what a codec is. Theory first, practice after.

Do you have any recommendations for literature on the subject of video encoding etc? I really want to learn more theory.

Re: What you need to know before touching a video file

#62

Post by ErroneousBosh »

weinzierl wrote: post #57

The article talks about image comparisons but does not say what the best way to extract an image is. If I want the best possible quality image at a precisely specified time, what would I do? Can I increase quality if I have some leeway regarding the time (to use the closest keyframe)? Is there a way to "undo" motion blur and get a sharp picture?

> Is there a way to "undo" motion blur and get a sharp picture?

Not really, no, any more than there is a way to unblur something that was shot out of focus.

You can play clever tricks with motion estimation and neural networks but really all you're getting is a prediction of what it might have been like if the data had really been present.

Once the information is gone, it's gone.

Re: What you need to know before touching a video file

#63

Post by ErroneousBosh »

weinzierl wrote: post #41

"Don't use Topaz AI, Anime4k, RealESRGAN, RIFE, etc. Trust me, just don't." Why? I only know Topaz and I always thought it had its narrow but legitimate uses cases for upscaling and equalizing quality?

Topaz looks bloody awful. Instead of big blocky upscaled pixels you've got weird artifacty "oil painting effect" smeary blobs.

Re: What you need to know before touching a video file

#64

Post by globnomulous »

jokoon wrote: post #34

I wish he talked about avidemux. It's a simple tool which is great for many things, it has filters and there are most of the formats. I think it uses ffmpeg under the hood. It's an old tool but it's fine for most things, when ffmpeg is to fastidious to use. ffmpeg is still what I use, but some more complex tasks are just more comfortable with avidemux.

> to fastidious

Do you mean "too fussy?"

Re: What you need to know before touching a video file

#65

Post by dylan604 »

jokoon wrote: post #34

I wish he talked about avidemux. It's a simple tool which is great for many things, it has filters and there are most of the formats. I think it uses ffmpeg under the hood. It's an old tool but it's fine for most things, when ffmpeg is to fastidious to use. ffmpeg is still what I use, but some more complex tasks are just more comfortable with avidemux.

Some of the simple tools might not be using ffmpeg per se, but using the libav or similar libraries. ffmpeg is just a tool built to utilize the functionality of multiple libraries like this.

Re: What you need to know before touching a video file

#66

Post by ffsm8 »

Etheryte wrote: post #17
embedding-shape wrote: post #9

It seems really weirdly written. It's written with a lot of authority, like saying "Don't use VLC" and "Don't use Y" yet provides no reasoning for those things. Just putting "Trust me, just don't" doesn't suddenly mean I trust the author more, it probably has the opposite effect. Some sections seem to differ based on if the reader knows/doesn't know something, but I thought the article was supposed to be for the latt…

Exactly, very hard to take the rest of it seriously after the VLC bit. VLC has literally never left me hanging, across I don't know how many decades. It's gonna take more than a trust me bro to challenge that.

You're talking about VLC for video playback, TFA is taking about video editing.

VLC ignores a lot for it's outstanding video playback support, which is great if you want the playback too just work... But that's the player perspective, not the editing/encoding

Re: What you need to know before touching a video file

#67

Post by dylan604 »

globnomulous wrote: post #64
jokoon wrote: post #34

I wish he talked about avidemux. It's a simple tool which is great for many things, it has filters and there are most of the formats. I think it uses ffmpeg under the hood. It's an old tool but it's fine for most things, when ffmpeg is to fastidious to use. ffmpeg is still what I use, but some more complex tasks are just more comfortable with avidemux.

> to fastidious Do you mean "too fussy?"

using a sledge to drive a finishing nail? yes, it's still a hammer and it's still a nail, but still the wrong tool for the job

Re: What you need to know before touching a video file

#68

Post by binarygit »

throwaway2046 wrote: post #8
BitsAndObjects wrote: post #5

Interesting read, it’s a shame the ranty format makes it 3x longer than necessary. Not sure why it takes a dump on VLC - it’s been the most stable and friendly video player for Windows for a long time (it matters that ordinary users, like school teachers, can use it without special training. I don’t care how ideological you are about Linux or video players or whatever lol).

VLC works great on Linux too! It's one of the few programs where I expect the exact same look and feel regardless of the underlying OS. mpv is okay but its complete reliance on command line flags and manually written config files makes it a bore.

VLC is pretty much one of the default things I download on any of my computers. Right now I use mac and it's my default video player here too!

Re: What you need to know before touching a video file

#69

Post by weinzierl »

ErroneousBosh wrote: post #62
weinzierl wrote: post #57

The article talks about image comparisons but does not say what the best way to extract an image is. If I want the best possible quality image at a precisely specified time, what would I do? Can I increase quality if I have some leeway regarding the time (to use the closest keyframe)? Is there a way to "undo" motion blur and get a sharp picture?

> Is there a way to "undo" motion blur and get a sharp picture? Not really, no, any more than there is a way to unblur something that was shot out of focus. You can play clever tricks with motion estimation and neural networks but really all you're getting is a prediction of what it might have been like if the data had really been present. Once the information is gone, it's gone.

If the estimation is good it might be enough for some use cases. Is there any software out there that specializes in this? Similarly to maybe AI colorizing or upscaling, which both guess information that is not there anymore.

Re: What you need to know before touching a video file

#70

Post by dylan604 »

swiftcoder wrote: post #42
gruez wrote: post #28

Earlier quoted context omitted.

>Really good quickstart guide It really isn't. You have to scroll 75% of the way through the document before you it tells you what to actually type in. Everything before (9000+ words) is just ranty exposition that might be relevant, but is hardly "quick".

Nah, see, I maintain a commercial video platform, and half the battle is people typing things in before they understand what a codec is. Theory first, practice after.

that's not a quick start guide. not once has the quick start guide with a printer explained the workings of the ink jet nozzle and the ability to precisely control the position of the head. it just says plug it in, hit this button to join wifi, open this app on your device, hit print.
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