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by Sunspark 1602 days ago
Fair, but in this case I think the tablet should be usable. Sure it's old and only a dual-core cpu, but checking the list of hardware accelerated qualcomm decoder codecs it supports, it lists: vc1, divx, divx311, divx4, avc, mpeg2, mpeg4, h263.

Surely AVC which is h.264 should still be supported..

Maybe it gets tripped up trying to use the software google decoder codecs instead?

That said, I am not able to test it anymore. The tablet is on kitkat and I'm not able today to find a site hosting a minsdk older than lollipop. It's not a big deal, but it's disappointing to see apks for services that used to work just disappear. They always gobble on about "security". Why is it a problem for everyone else except Netflix? Netflix loves supporting devices.

2 comments

"Supports AVC" doesn't mean a great deal on its own. H264 has a number of different profiles (over 20, although only 3 are commonly used), and 20 different levels. Most of the potential combinations aren't relevant, but supporting the full range of hardware decoders while also sending something reasonably close to the best quality that the device supports can mean encoding ten different versions.

If it's a particularly low-end/old device, Amazon may have simply decided it's no longer worth encoding a version supported by your device's hardware encoder, while Netflix still does.

Can you recommend any resources for learning about video codecs?
Not sure if this is what you’re looking for, but this popped up a while back: https://blog.tempus-ex.com/hello-video-codec/
This is vaguely okay but makes the common mistake of overemphasizing that codecs use an IDCT. That's just a component of intra-prediction, it isn't necessarily important or used, and in H.264+ it isn't even a real IDCT when it is used. It's a simpler transform that isn't mathematically accurate but is bit-exact, which is more important.
This is perfect! Thank you!
doom9 has a lot of good discussion.
I remember back in the day when doom9 was blocked at the corp firewall level because it had posts on how to circumvent things. Nevermind it was the unofficial support for things like AVISynth, x264, etc. Even the nascent days of ffmpeg were there. It took a lot of cajoling and back and forth with legal depts, but eventually, was allowed to be granted access on an individual basis

I owe a lot of what was accomplished to folks like DG and the other troopers from the bad ol' days of VFW based apps. It was like monkeys throwing rocks at the space ships compared to whats now. Remember when 2 cores was fast?

For the person up thread talking about learning things, I wish I was in that position today with them rather than 20 odd years ago where everyone was in the dark, and thank the heavens for sites like doom9 that shone lights in dark places!

>For the person up thread talking about learning things, I wish I was in that position today with them rather than 20 odd years ago where everyone was in the dark

Where would you start today?

And what was being circumvented? Copyright protection?

DeCSS was considered a very big no no if you worked for a company that did work for content owners. Doom9 had lots of info on how to use DeCSS, and so it was flagged by lots of corps.

Where would I start today? That depends on your level of interest, and what you want to do. Are you wanting to learn things to do to stay hip and cool making videos for the socials, or are you wanting to do technical things to video for less prestigious ends? That's two different paths that intertwine, but different recommendations depending.

That's not a rhetorical question, btw. I've been in both fields, and continue to work in both. There's lots of reading, and today watching videos, but the biggest thing will be the access to actually doing the things that weren't possible so freely 20 years ago. Try things, make mistakes, learn, do again.

I am interested in using video compression to improve delivery of VR and AR content over the web. But, this can mean a lot of different things! I know there is a lot of opportunity for this, I have a lot of ideas, but my knowledge of video compression and video streaming is limited. There are some companies working on this, but it’s not a singular problem or solution. I expect it will end up being many categories of solutions.

I usually like to learn about things from first principles so that I can then choose what to intentionally skip over, if that makes sense. I find the history is usually a good place to start, but it only goes so far with these more blackbox type topics like video compression.

Now we’re talkin! Thank you!