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Adventures with ffmpeg and color ranges

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Re: Adventures with ffmpeg and color ranges

#72
post #67

I see a lot of people confused about the host (Facebook). Carmack initially posted a lot of high quality articles on AltDevBlogADay. However, that site went down. Carmack said he moved to Facebook because he feels it's more reliable than other (cleaner) third-party hosts, which might not be around 10 years from now.

I've seen a lot of similar posts hosted on Google Plus and shared on HN in the past. They are all gone, now.

Sure, Google has a horrible track record when it comes to service durability, but I wouldn't trust Facebook as a reliable host either. Anyone having relied on their @facebook.com email address (2010-2016) may agree.

Re: Adventures with ffmpeg and color ranges

#73
post #53

For all of our sanity, please don't start producing 8-bit H.264 videos with full 0-255 range. If you have enough control over the decoder and renderer to make that hack work, you should just be producing 10-bit HEVC/AV1 video – which does not suffer from these 8-bit banding issues – with a modern color space (Rec 2020, PQ, etc.). And if you don't have choice or control over the decoder and renderer, then it's a good…

My primary concern is for immersive VR media on our Go and Quest platforms, which use Snapdragon 821 and 835 SoC, respectively. The 821 doesn’t support 10 bit on anything, and the 835 only supports it on h265. Software decoding a 4k60 video on mobile isn’t an option, and you can see every bit transition with dark adapted eyes in a vr headset, so getting full 8 bit range is pretty valuable.

Re: Adventures with ffmpeg and color ranges

#74

I still find it kinda odd that this is still the best tool out there for this sort of work. Archaic parameters and options and exceptionally hard to read documentation. Maybe I'm just dumb and not in the domain enough to get a decent handle but everytime I use ffmpeg I feel like a Norse Shaman trying through trial and error to locate the correct orientation of runes for the blessing.

Handbrake is a popular GUI on top of ffmpeg.

Re: Adventures with ffmpeg and color ranges

#75
post #64

I still find it kinda odd that this is still the best tool out there for this sort of work. Archaic parameters and options and exceptionally hard to read documentation. Maybe I'm just dumb and not in the domain enough to get a decent handle but everytime I use ffmpeg I feel like a Norse Shaman trying through trial and error to locate the correct orientation of runes for the blessing.

there are two problems here. the main problem is that nobody reads the manual, which actually starts out half-decent. the description is very clear, concise, and even contains the oft-whinged-about examples. https://ffmpeg.org/ffmpeg.html the second problem is that ffmpeg has a lot of features, and nobody wants to go through and fully document hundreds of formats, codecs, and filters.

I'll be adding entries for all the missing demuxers/decoders/encoders/muxers eventually. At present, only a fraction have been documented.

Re: Adventures with ffmpeg and color ranges

#76
post #53

For all of our sanity, please don't start producing 8-bit H.264 videos with full 0-255 range. If you have enough control over the decoder and renderer to make that hack work, you should just be producing 10-bit HEVC/AV1 video – which does not suffer from these 8-bit banding issues – with a modern color space (Rec 2020, PQ, etc.). And if you don't have choice or control over the decoder and renderer, then it's a good…

So to clarify, you don't agree that anyone should use -pix_fmt yuvj420p when encoding video to share with others?

Let's say I have a video with full RGB range 0-255 video. Why would 10-bit be a better option than 8-bit?

Re: Adventures with ffmpeg and color ranges

#77
post #67

I see a lot of people confused about the host (Facebook). Carmack initially posted a lot of high quality articles on AltDevBlogADay. However, that site went down. Carmack said he moved to Facebook because he feels it's more reliable than other (cleaner) third-party hosts, which might not be around 10 years from now.

I just happened to find where he said that: https://news.ycombinator.com/item?id=17068101

"Years ago, I felt burned when I wrote several articles for #AltDevBlogADay, and they vanished. I have much more confidence that what I write on FB won't vanish. [...]"

Re: Adventures with ffmpeg and color ranges

#78
post #56

Earlier quoted context omitted.

Oh wow, you really have to hope these are not the canonical links. If so, they are doing themselves an incredible disservice and the fact that no one has brought it to management's attention speaks gravely to the workplace culture there.

Not only does the full URL not show in my browser (Safari), the full URL doesn't even show on this forum (for me it is cut off after "content"). When you receive a URL via chat or on social networks, it is in the form of a preview and might not even show the domain name. The user also isn't typing these URLs in, with or without human readable text in the path. Essentially all of the arguments for making URLs more bri…

> Essentially all of the arguments for making URLs more brittle (which is what you are doing by adding human readable text)

Not if done right, like e.g. stack overflow, see https://stackoverflow.com/questions/517355/string-formatting...

The human readable text is actually meaningless, and anything after the id will redirect there, e.g. https://stackoverflow.com/questions/517355/this-could-be-any...

Re: Adventures with ffmpeg and color ranges

#79
post #58

Not sure if this kind of meta-comment is appropriate, but I find it difficult to follow a link like this because of the lack of human readable information contained in the URL. If the story was hosted on a personal blog I recognised (like Julia Evans to take a random example), then perhaps the domain would be enough for me to choose to read the article to see if the content is interesting. If the link was to a broade…

Isn‘t a quick glance at the article enough to decide whether or not to read the article? It‘s not like you are forced to read the article after all.

I think the point OP is making is that they won't even click the link in the first place.

Re: Adventures with ffmpeg and color ranges

#80
post #64

I still find it kinda odd that this is still the best tool out there for this sort of work. Archaic parameters and options and exceptionally hard to read documentation. Maybe I'm just dumb and not in the domain enough to get a decent handle but everytime I use ffmpeg I feel like a Norse Shaman trying through trial and error to locate the correct orientation of runes for the blessing.

there are two problems here. the main problem is that nobody reads the manual, which actually starts out half-decent. the description is very clear, concise, and even contains the oft-whinged-about examples. https://ffmpeg.org/ffmpeg.html the second problem is that ffmpeg has a lot of features, and nobody wants to go through and fully document hundreds of formats, codecs, and filters.

The third problem is that video is _complicated_. What does the nal-hrd=cbr do? Well you need to understand the HRD model and (which is about 5 pages of dense specs).

Ffmpeg does a great job of guessing _what_ you want. But as soon as you're outside of those guesses you need to know _a lot_ to get things working.

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