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I made a cell phone [video]

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Re: I made a cell phone [video]

#71
post #62

He mentioned that he bought that cnc machine like it was no big deal. I looked them[1] up, the cheapest one was 6 grand!! Does there exist a sub 500$ cnc router that you can actually build interesting stuff with and interface with a computer? [1] http://www.shopbottools.com/mProducts/basicPRSsystems.htm

On the speaker page for the conference this took place at, it says that Kevin is a hobbyist industrial designer. Likely a good purchase for him!

Re: I made a cell phone [video]

#72

Earlier quoted context omitted.

Yeah, that trick is also useful for older machines which are otherwise too slow to play stutter-free youtube video in a web browser. The VLC implementation appears to be significantly more CPU efficient.

Probably pulls the h264 version instead of VP8/9.

That's probably not why. h264 would indeed use less cpu time than vp8 if there was hardware acceleration from the graphics driver available and being used for h264 but not vp8 (which is plausible). But software decoding can be pretty efficient in dedicated video players, and browsers and flash can be pretty damn slow at just getting decoded frames to display.

Back in 2010 I was using a computer I built in 2004, which had a single-core athlon64 3200. Watching standard definition video in Hulu was a blocky slideshow, totally unusable. But I could watch 720p h264 video at a decent bitrate, with mplayer, with no hardware acceleration.

One of the bigger differences is that browsers/flash have to put the video output as a surface that they composite with the controls on top and the rest of the page behind. Old-style video players actually render to a different hardware "overlay" plane and don't mix anything with it in software, and it makes a huge difference.

(My mplayer example is from linux, but I've also used MPC on windows a lot. You can change the renderer in the settings, and "overlay" doesn't support showing subtitles, but has noticeably faster/smoother performance. Well, back on windows XP.)

Re: I made a cell phone [video]

#73
post #60

That guy is smarter than me, funnier than me, and most importantly works harder than me.... but I have an iPhone.

I'm not sure what you're trying to say with the iPhone part?

I guess that the iPhone does more things than the phone the guy made.

Re: I made a cell phone [video]

#74
post #72

Earlier quoted context omitted.

Probably pulls the h264 version instead of VP8/9.

That's probably not why. h264 would indeed use less cpu time than vp8 if there was hardware acceleration from the graphics driver available and being used for h264 but not vp8 (which is plausible). But software decoding can be pretty efficient in dedicated video players, and browsers and flash can be pretty damn slow at just getting decoded frames to display. Back in 2010 I was using a computer I built in 2004, which…

You think VLC pulls the VP8/9 version instead of the h264 version? I seriously doubt it. Why would it? It would make no sense. Most devices have h264 hardware decoders. Most don't have VP8/9 decoders (though they exist).

I also have no doubts that an Athlon64 could decode 720p h264 completely in software. You'd be pegging that single core pretty high, but it could do it.

Re: I made a cell phone [video]

#75
post #72

Earlier quoted context omitted.

That's probably not why. h264 would indeed use less cpu time than vp8 if there was hardware acceleration from the graphics driver available and being used for h264 but not vp8 (which is plausible). But software decoding can be pretty efficient in dedicated video players, and browsers and flash can be pretty damn slow at just getting decoded frames to display. Back in 2010 I was using a computer I built in 2004, which…

You think VLC pulls the VP8/9 version instead of the h264 version? I seriously doubt it. Why would it? It would make no sense. Most devices have h264 hardware decoders. Most don't have VP8/9 decoders (though they exist). I also have no doubts that an Athlon64 could decode 720p h264 completely in software. You'd be pegging that single core pretty high, but it could do it.

My point was that the hardware acceleration, and vp8 vs h264, doesn't really matter. The computation power of processors sold in 2010, even those in not-very-thick laptops, was probably double my Athlon64. The difference is everything else, the UI stuff (and maybe also flash and browsers being less efficient at decoding than ffmpeg).

Re: I made a cell phone [video]

#76

Feels like I'm watching some sitcom. Does anyone else feel the people are laughing too much?.. or probably the microphone is very near to the audience.

Yup, I do agree that some things were really funny, but it felt like the audience started laughing no matter what he said.

Re: I made a cell phone [video]

#77
post #57
post #23

I gave this talk. Slides are here: https://keminglabs.com/talks/#bangbangcon2015 I'll post some photos of the current version and more details on my twitter (@lynaghk) tomorrow (in 10 hours). Software is all on an 8-bit Atmel microcontroller, written in C in the style of Harel Statecharts ( http://www.inf.ed.ac.uk/teaching/courses/seoc/2005_2006/reso... ).

Very nice! :-) Could you list the name of the various CAD packages you used? (For the PCB layout and modelling the box)?

I used Autodesk Inventor w/ HSMWorks for the physical enclosure (both packages have 30 day free trials).

For the PCB, I tried using Eagle (very tedious / confusing) and KiCAD (couldn't figure out how to install on OS X without compiling from source) and ended up using Altium Designer via a friend's dad, who is an electrical engineer. Unlike Inventor / SolidWorks, Altium was very tedious and confusing and I was stuck until I bought an excellent video course on the topic: http://www.fedevel.com/academy/

Re: I made a cell phone [video]

#78
post #62

He mentioned that he bought that cnc machine like it was no big deal. I looked them[1] up, the cheapest one was 6 grand!! Does there exist a sub 500$ cnc router that you can actually build interesting stuff with and interface with a computer? [1] http://www.shopbottools.com/mProducts/basicPRSsystems.htm

I bought a ShopBot Desktop with a spindle, and it cost about $8,000. I decided that I wanted to focus on my phone project, rather than on trying to get a cheaper/homemade machine to work properly. (It's the same reason I bought an Apple laptop.)

If your budget is limited but you still want to get a sense of designing/making physical objects, buy a lot of Renshape foam, x-acto knife, and laser print designs to trace/cut.

Once you do that for a few hundred hours on your designs, shoot me an email and I'll be happy to mill them out for you = )

Re: I made a cell phone [video]

#79
post #75

Earlier quoted context omitted.

You think VLC pulls the VP8/9 version instead of the h264 version? I seriously doubt it. Why would it? It would make no sense. Most devices have h264 hardware decoders. Most don't have VP8/9 decoders (though they exist). I also have no doubts that an Athlon64 could decode 720p h264 completely in software. You'd be pegging that single core pretty high, but it could do it.

My point was that the hardware acceleration, and vp8 vs h264, doesn't really matter. The computation power of processors sold in 2010, even those in not-very-thick laptops, was probably double my Athlon64. The difference is everything else, the UI stuff (and maybe also flash and browsers being less efficient at decoding than ffmpeg).

Well, on a single core you are going to hit issues with multiple processes running. If you have the browser, flash, network, and decoding all happening on a single core, it wouldn't be surprising to see stuttering. Obviously, offloading the decode to a different processor would help out, but so would running just a single process.

Re: I made a cell phone [video]

#80
post #72

Earlier quoted context omitted.

That's probably not why. h264 would indeed use less cpu time than vp8 if there was hardware acceleration from the graphics driver available and being used for h264 but not vp8 (which is plausible). But software decoding can be pretty efficient in dedicated video players, and browsers and flash can be pretty damn slow at just getting decoded frames to display. Back in 2010 I was using a computer I built in 2004, which…

You think VLC pulls the VP8/9 version instead of the h264 version? I seriously doubt it. Why would it? It would make no sense. Most devices have h264 hardware decoders. Most don't have VP8/9 decoders (though they exist). I also have no doubts that an Athlon64 could decode 720p h264 completely in software. You'd be pegging that single core pretty high, but it could do it.

Well, you'd use 30% less bandwidth (and therefore start / seek faster).

In addition, decoding VP9 in software is actually faster than H.264 with ffmpeg, the decoding library that VLC uses.

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