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David Jordan
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David Jordan

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This hackfest is coming to an end.  It's almost time to embrace some sanity.
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I tried sanity once. No fun at all.
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David Jordan

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Yep, feeling pretty good about the new rendering architecture.  The new way is going to be a lot more flexible and make producing perfect edits consistently much easier.  Also exciting for laying the groundwork to add new editing functionality.
 
I wrote a script to go through my database of existing +Novacut edits and re-render them with the new experimental rendering backend. This has helped expose a number of issues, but so far they've been pretty easy to fix. The new backend still feels extremely promising, especially considering we're just finishing up our 2nd day of work on it.

Huge thanks to +David Jordan for coming up with this new approach. The idea we've been experimenting with is 100% his (and was the result of a lot of grueling effort he put in with other approaches that ultimately proved dead ends). Evidence strongly suggests he nailed it with this one!

This video shows the +Dmedia  visualization tool that +James Raymond designed and implemented a while back for a demo.
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+David Jordan and I started a 4-day +Novacut hack fest today.

First we've focused on a  feasibility study for a new Novacut rendering backend, and thus far the results have been extremely promising.

It's not a huge change architecturally as we're still using +GStreamer, although we will be using it quite differently in one key area. It's also not about new features as editing fundamentally isn't about features... it's about editing.  Which has actually changed very  little in the past 50 years.

To clarify: go shoot a few dozen reels of film, then sit yourself down at a light table with some scissors and scotch tape. That's what I mean by editing. It's also what anyone who has worked in a Hollywood-esque production pipeline means by editing.

I want Novacut to have the clarity of a light table, scissors, and tape. We have still have lots to do on many fronts, on both the design and the technology side. But I think we've done a good job staying focused, even if it takes a long time to get there.

During this hack-fest we're tightening up some technology areas that we just can't put off any longer:

1) We need to focus more on the stability and performance needed for feature length, high complexity edits

2) We need to be able to deliver flawless frame-accurate renders, without fail, over and over, every time (we've historically done pretty darn well on this, but it's never been perfect... and we need perfect here)

One nice thing about the Novacut edit description is that video cuts (what we call "slices") are specified by [start:stop] video frame indexes rather than time. This means that, for example, we know the exact total number of frames that the render of an edit should contain. So we can check that every time we render a particular edit we get the expected number of frames, not one frame more, not one frame less.

I've grown increasingly fond of using large, randomly generated edits to test both stability and frame accuracy. And our experimental backend took us to new heights today, allowed us to do things we couldn't previously.

I just successfully rendered a randomly generated test edit that:

* Had 658,051 frames
* Contained 5,120 slices
* Was 6 hours, 5 minutes, 56 seconds long
* Produced a 20.7 GB video

Not only is the new renderer stable enough to do this already after just a day of work, and not only could it did so with a very flat memory profile over the 7 plus hours this test took...

But every one of those 658,051 frames were rendered exactly as specified by the edit description. Not a frame was dropped or duplicated. And the outgoing timestamp and duration of every frame was mathematically perfect, without fail.

There is a pretty amazing visual difference between a render that is generally frame accurate, give or take a little wiggle, and a render that is by the numbers truly perfect. I'll do a shorter test render tomorrow and will upload the result. For now, just a screenshot of Totem playing that 20GB file, as I don't think I'll be uploading it anytime soon :P
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Ahh, this is awesome! Love to hear of this!
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David Jordan

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My latest creation incelebration of New Horizons (and my birthday)!
Like some of my characters, I sometimes like to have fun injecting science and engineering into everyday things! That and obscene amounts of chocolate. So I made a cake to celebrate both my birthday and the amazingness of the New Horizons mission to Pluto. Seriously, we've just seen the first new sun-orbiting world up close in over 25 years! Just one birthday cake ago Pluto was a tiny speck of light, and now it's this:
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David Jordan

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Beautiful.  It truly is amazing how well much clearer we can see Pluto now.  Until the last few weeks we only saw a point of light, where now we see a (dwarf) planet.
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Call it a "world". That's what Sagan did for the large Galilean satellites.
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David Jordan

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New scene (still WIP) from Nina Paley!
 
Shabbat shalom! I just posted a little Seder-Masochism opening scene-in-progress: https://vimeo.com/118255690 More soon.
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This is the world I want to live in.
 
Here's why I'm giving ALGORITHM away for free in 5hrs: http://www.brandxindustries.com/blog/2014/12/4/the-free-future-starts-now then watch it at: www.thehackermovie.com
Piracy is not going to stop nor should it. It’s a good thing!     That realization is the result of conversations I’ve had with fellow writer/directors...
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David Jordan

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The new rendering backend by me and +Jason DeRose has been exposing the quirky ways gstreamer elements play with timestamps all weekend.  By providing perfect timestamps, we're getting a great look at how each encoder and muxer wrangles and mangles the data. 

First, we noticed that GStreamer's Matroska muxer zeroed out everything after the millisecond.  MKV's official spec has a TimecodeScale property, which indicates the granularity of the actual timecode (defaulted to 1000000...which indicates the timecode is in milliseconds.  Setting TimecodeScale to 1 would give nanosecond precision.)  Sure enough, matroska-mux.c sets the value to GST_MSECOND...1000000. 

Next up, we found weirdness in qtmux when using x264 unless the keyframe interval was set to 1 (all keyframes).  Using mjpeg with qtmux also resulted in well-behaved timestamps.  This is probably partially the result of x264 weirdness, but we think qtmux is doing some odd things of its own.

Theora/Ogg was pretty well-behaved too, but would rarely be off by a single nanosecond.  

Also, qtdemux appears to set the framerate by looking solely at the duration of the first timestamp.

#NovacutHackfest #GStreamer #Timestamps  

http://www.matroska.org/technical/specs/index.html
http://cgit.freedesktop.org/gstreamer/gst-plugins-good/tree/gst/matroska/matroska-mux.c

http://cgit.freedesktop.org/gstreamer/gst-plugins-good/tree/gst/isomp4/gstqtmux.c
http://cgit.freedesktop.org/gstreamer/gst-plugins-good/tree/gst/isomp4/qtdemux.c
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I find it annoying that MKV doesn't allow the frame duration to be any rational number. It means you have to either accept a slight timestamp drift or end up with an apparently variable framerate file with all the issues that brings.
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David Jordan

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The Pluto Cake is here with its orbital mechanics and science to do!
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This is why in textbooks growing up I always found "artist renderings" for what Pluto looked like.  No longer will children have to settle for pictures no more accurate than matte paintings from Star Trek.
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We'll still have all the artists' renderings of extrasolar planets. :-)
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Live Long and Prosper, Mr. Spock.  May you boldly go, seeking out new life and new civilizations.  Our human journey continues without you, but you will be remembered.
 
Horrible sad face. :'(
In addition to acting, Mr. Nimoy directed films; published poetry, autobiographies and books of photography; and recorded music.
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David Jordan

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Watch +Jon Schiefer 's movie, Algorithm on YouTube.
 
Sharing without permission is stealing in many countries. That'll change when society recognizes that sharing has more value than money. When someone shares a file they're not lowering its value, quite the opposite. Sharers risk their freedom to show the new information/thing to with their friends. That's priceless! The problem is that we're now in a transitional phase, the time-between-times, when some of society has changed and some of it hasn't. So, I will be sharing with the sharers and extracting money from the capitalists. That's the transitional model.
www.thehackermovie.com
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