About

Michael Zucchi

 B.E. (Comp. Sys. Eng.)

  also known as zed
  & handle of notzed

Tags

android (44)
beagle (63)
biographical (103)
blogz (9)
business (1)
code (74)
compilerz (1)
cooking (31)
dez (7)
dusk (31)
extensionz (1)
ffts (3)
forth (3)
free software (4)
games (32)
gloat (2)
globalisation (1)
gnu (4)
graphics (16)
gsoc (4)
hacking (455)
haiku (2)
horticulture (10)
house (23)
hsa (6)
humour (7)
imagez (28)
java (231)
java ee (3)
javafx (49)
jjmpeg (81)
junk (3)
kobo (15)
libeze (7)
linux (5)
mediaz (27)
ml (15)
nativez (10)
opencl (120)
os (17)
panamaz (5)
parallella (97)
pdfz (8)
philosophy (26)
picfx (2)
players (1)
playerz (2)
politics (7)
ps3 (12)
puppybits (17)
rants (137)
readerz (8)
rez (1)
socles (36)
termz (3)
videoz (6)
vulkan (3)
wanki (3)
workshop (3)
zcl (4)
zedzone (24)
Tuesday, 22 May 2012, 08:15

Ubuntu is still snot.

Some business was throwing out a couple of old laptops and my flatmate ended up with one: which means I get to try to make it work. After waiting about 8 hours for it to book the ubuntu live cd a couple of times I thought it wasn't going to be much use: until I opened the SODIMM cover and saw the 512MB module had fallen out. At least 768MB makes it almost usable ...

But yeah so I ended up installing xubuntu 12.04 (I didn't just go with fedora because that's a pain if you're using XFCE as well, not to mention all that systemd and other crap). I can't say I have much good to say about it on first impressions:

All it really needs to do is play videos and visit youtube, so i'm not asking for much. If I can get it that far along I will leave it.

Tagged rants.
Friday, 18 May 2012, 06:52

Citrus Day

Handed off the prototype i've been working on for the last 8 weeks to the project manager last night; fairly pleased with the result in the end. But given it was a bit of a slog and I will switch gears next week back onto algorithms (yay, and OpenCL), today seemed like a good day for a break ... and to catch up on some preserving.

The citrus has all gone crazy this year.

And this is after I've picked about 40 kaffir limes (actually, they fell off), and the bowl of kumquats in the next photo. I juiced the kaffir limes last week and ended up with about 700ml (and a whole lot of rind in the freezer), although about all i've found to do with the juice is as a scalp/hair treatment. The lemon tree in particular has been so loaded the tree itself is in fear of falling apart. But they're not quite ready yet - they're only meyers anyway, so are fairly sweet - I've already tried some by peeling them, separating the segments and sprinkling with sugar. Tastes pretty close to grapefruit actually, although not so bitter and thus a bit nicer.

The mandarine tree still has plenty on it too - we've been eating them every day and giving away bags of them but you'd barely tell looking at the tree. Most have them have been nice and tart and juicy too.

So what to do with these - they surprisingly go a long way for such a small fruit. I had previously done some brandied kumquats which a friend particularly liked, so I thought i'd start with that - and give it to him as a birthday present.

I used a recipe I found some time ago but haven't been able to re-find: equal parts by weight of kumquats, sugar, and brandy. This is a 2800ml jar, so i've got about 900g kumquats, 900g sugar, and 900ml of brandy. I got some cheap glass jars at a $2 shop, and they worked pretty well apart from some pretty cruddy seals (but they'll do). The sugar will take a few days to fully dissolve. After about 6 months you get something that takes pretty much like a citrus version of a tawny port - obviously quite sweet but with a fairly balanced flavour of tart & bitter as well.

So I still had a few left over from the initial picking so I scoured the net for some other ideas - last time I had a decent crop I made some marmalade, but I still have plenty of that left! (from 4 or 5 years ago) I thought i'd try preserving them like lemons, so a good cup-or-two of salt later, a bit of lemon and lime juice, and some stinging fingers and there you have it. I really have no idea if these will work at all, but apparently they're good for something after a few months. Based on something approaching this recipe (although "some salt" is hardly a useful fucking measure ...) together with this one for lemons from The Cook and The Chef. Who knows if i have too much salt, but if nothing else it looks nice.

And finally my lime tree has been dropping limes enough that cooking can't keep up with them, so I wanted to make some lime cordial ('syrup' for you yanks). Again this is something that goes a long way, with 7 limes I had 2l of cordial (I usually mix it about 6:1), but it's a really nice summer drink. Pity it's a long way from summer. As there are more ready to drop I will probably make ice-cubes of it next time. I used this recipe although I only used 1kg of sugar, and bottled it whilst hot without straining. The old lady had a great recipe from her Green and Gold recipe book but she threw the book away years ago ...

And yes, it's yellow, but it's still all lime juice, which was a nice shade of green going in. Although I added a bit of lemon zest, and most of the lime zest was also fairly yellow as the limes are proper-ripe. I normally leave all the zest in as the sugar more than makes up for any bitterness they might add, and it looks nice.

I also have a very small number of west-indian limes - the very small ones with seeds in them - so i'm not sure what to do with them. They are super-tart though.

Bombay Sapphire bottles with the labels removed make very nice storage bottles too. Must get some more since I have all these limes handy (for the gin that is ;-), although it's been a bit of a dangerous drink for me lately (it's just too easy to sink them down).

Tagged cooking, horticulture.
Monday, 14 May 2012, 00:19

driver bugs?

Over the weekend and Friday I spent a good 3 days worth of full-time hours trying to debug the player in jjmpeg (and still did nothing Sunday).

At least along the way I discovered the profiler, overheads of using a BlockingQueue(), memcheck in the emulator, enabling GLES2 in the emulator, hooked up the decode_audio4 api, and a few other odds and sods.

But, the more I look, the more it looks like i'm hitting a bug in the driver. Given how new the tegra3 stuff is, and given it's nvidia, it wouldn't surprise me. I still consider labelling it a driver bug a 'last resort', since it's such a basic feature, but i'm running out of other possibilities here.

I've tried java side or c side glTexSubImage2D(), i've tried copying the AVFrames, or copying the AVPlane's to pre-allocated or dynamically allocated bytebuffers, i've tried using a single AVFrame for decoding or a cycling buffer of them. Although sometimes one mechanism seems a bit more reliable (and i even managed a full run-through the hour-ish video i've been using to test) eventually they all crash. If all I do is remove the texture loading (glTexImage2D and glTexSubImage2D calls); then it doesn't.

This has been just a huge waste of time now i'm getting pissed off with it.

I could try writing a simpler bit of code to isolate the driver code, but given it's crashing inside FFmpeg it probably wouldn't provide enough logic to cause problems if I did that. Which probably means returning to software colour conversion and resorting to a Bitmap as the image surface ...

I wrote the above Saturday morning but kept poking - now i'm not so sure. Maybe it's something to do with the audio decode. Early on in the piece I had a packet-checker checking that the packets were padded properly - and it showed they weren't. But then I moved to the decode_audio4() api and haven't re-checked. Still, using gles2 with no audio stuff at all still causes problems as well, so it can't be just that. And the solid valgrind results from the emulator show that it's not suffering from memory nastiness as I originally thought. Assuming they can be trusted.

Tagged android, hacking, java, jjmpeg.
Sunday, 13 May 2012, 03:34

Maker? WTF is a maker?

By happenstance - as I just don't bother reading the news much these days much less specific papers - I came across this interesting article about the 'hacker culture' this morning in the age.

First i've ever heard hackers wanting to be known as 'makers'. Sounds a bit faffy and overly-pc if you ask me. I had seen 'maker' sites, but I thought that was just a brand-name, and not a movement ...

I have no problem calling myself a hacker, but then again it's not like i'm talking to anyone but myself ;-)

George finishes with the question: could Australia develop it's own 'Silicon Valley'? And I think the answer is simple: No, no it couldn't.

Education

First, there is the education system. Computers are now just mechanisms for running software from Microsoft, Apple, Adobe, or other large US companies. One doesn't start with an 'introduction to computers' covering 'word processing, spreadsheeds, and programming', all you get is: Microsoft Excel, Microsoft Word. If one progresses ever past that point it is merely to 'Photoshop', or maybe avoiding stalkers on the intertubes.

In primary school we had one Commodore 64 in the whole school and as a `bonus' for finishing class work early we sometimes got to type in computer programmes (often from Compute!, which used it's own checksummed number entry system - so it was pages of hexadecimal numbers). High school had a pool of crappy Apple ]['s, but even then word-processing, 'desktop publishing' and spread-sheets were only a small part of the course, which ended with programming. And this was in year 8.

Gone are the days when education was about educating people, now it's just low-level training for stuff anyone who will ever work in the field has already done before they start school: using a mouse, using a crappy 'word processor' (which sadly, is still just as crap as they were back then: i.e. a fancy type-writer), and how to run an internet search.

Hackers of course have always gone beyond the education system, but if you're repeatedly told that computer software systems are locked up private applications which no user serviceable parts, it has to have some impact.

Also this notion of training for specific products that 'industry wants' is utter nonsense. First, you will never cover enough in high school (or even TAFE) to avoid on-the-job training specific to the business needs. And second you are always much better off being exposed to as many different systems as possible. The human brain is an incredible organ, and even more-so during developmental years: like any adaptive system, the more you expose it to, the stronger and more robust it becomes. Intentionally crippling its development by limiting it's exposure to alternatives borders on criminal.

Complexity

Systems are so much more complex than they were back when Silicon Valley got it's start. Not only to write code for, but expectations are much higher.

Back in the day I could spend a whole weekend typing in a bit of BASIC to get an animated lo-res horse-sprite running across the screen and I was impressed enough just with that. And even then; the actual code required just wasn't that much and you were talking directly to well designed simple hardware. You literally could design a whole computer itself on the back of a napkin, let alone the software.

Today you need a bulky IDE to get very far, to learn some gigantic and usually poorly documented toolkit, which goes through another toolkit, through an operating system, then a driver, and if you're lucky to the screen. And you don't feel satisfied until you've come up with the next billionaire-making 'killer app'. And to make matters worse the hardware is devilishly complex; so complex it never really gets working properly and needs to be hidden behind layers of drivers and high level apis - which it necessarily must be for an operating system to function - but makes it that much more challenging to understand what is going on (which as a hacker: you need to know sometimes).

The barrier to entry is huge, and for all intents beyond the reach of most individuals. This leads them to believe there's no point in trying, and creating software is exclusively for the great wizards who doth do such things (and must be paid accordingly).

This complexity affects every level: so beyond the individual then you have large complex systems which take many man-years to create.

Silicon Valley also had a unique combination of hardware and software mixed together allowing both to leap ahead in bounds together - something which would only be possible in China or Taiwan at the moment. But they're not interested in the software or the hardware design, just in making throw-away junk cheaper than everyone else.

Fucked up Legal system

And then we get to patents and so on. It is now impossible for anyone to create any piece of useful hardware or software without stomping on someone's stupid patent in the USA. Which means effectively everywhere in the world as all of our local politicians have kowtowed to the almighty US dollar and wont dare to argue for their or our own interests.

It would simply be impossible for Silicon Valley to become Silicon Valley in today's legal environment. The whole notion was based on a solid foundation of sharing of ideas and people, and a free flow of money. This latter point alone rules out Australia ever being more than a bit-player in the game, things just aren't done that way here.

The USA wouldn't let us

So this is related to the previous point, but the legal system is just one tool they use for this.

The USA is the dominant military, political, cultural, and financial force of the day. They do not let anything get in the way of that dominance. Anyone who thinks otherwise just hasn't been paying attention.

e.g. The H1B visa programme in the USA isn't about US companies not being able to get enough talent at home; it's about preventing any of the talent from being used by competitors.

If Australia ever had a Silicon Valley it would only be at the divine blessing of the USA. It would almost certainly be in the form of a 'technological partnership' with an IBM, or a university. And these are just talent syphoning systems.

Pretty unlikely for that matter - just not enough people, too high wages, that's why they've set-up shop in India and elsewhere.

The tyranny of distance, money, etc

Australia is just too big and too thinly populated to create a high enough density of a specific type of people needed for such a thing to occur. Not to mention too parochial - although a lot of people would travel interstate for work, plenty wouldn't.

The NBN has the potential to remove the distance factor, but even if that ever gets done properly - it just doesn't create enough connectedness for it to work effectively. If people aren't excitedly talking about their latest idea in the pub with competitors the ideas just aren't sharing quickly enough (this will be silicon valley's downfall - already a lot of the exiting stuff is happening elsewhere).

And you need all that excess money to throw at random ideas as well. Which basically means you have some source of free money - imperialism, oil, the world's trading currency, or somesuch.

We will never have that here. And even the great source of free money here at the moment - mining - only seems to produce overweight greedy arseholes (an unusually number of whom are remarkably fugly to boot) who have no interests beyond their own fat arses.

Tagged hacking, rants.
Friday, 11 May 2012, 06:25

The World Wide Web

So M$ are up to their old tricks again and restricting competitors from accessing their operating systems properly. Nothing ever changes apart from the date. Does it really matter much anyway? (who in their right mind is even going to use that shit to start with?). Mozilla are still pushing their it's-really-an-operating-system angle, but is that really ideal for me as a customer? Or even as a developer for that matter. One only has to look at any application on a tablet and compare it to it's browser counterpart. Even running on a monster desktop workstation the tablet usually beats the pants of it. e.g. google maps or youtube. For all it's "lowly" specifications (well, they aren't really), the tablet i've been using shits all over anything i've ever seen in a web browser, HTML5, or Flash, on much much faster machines. I would really like to see browsers eschew all that heavy-client crap which has turned them into bloated power wasters, and return to a world of delivering information in an open and linked way. This is something they actually do quite well, and then they can leave the heavier stuff to native applications which always do a better job. And with the range of devices exploding - from workstations to tv's to pocket computers - doing anything more than text with a few pictures, the odd form, is only going to become more difficult. The right tool for the right job, and all that.

Tagged philosophy, rants.
Friday, 11 May 2012, 02:35

Abject failure

I spent an inordinate amount of time last night trying to lick the decoder stability issues.

I ported the jjmpegdemo MediaPlayer over to android, and re-arranged it so it was shipping AVPacket's around instead of AVFrames and decoding on a separate thread (this is how ffplay does it). I changed the rendering to copy to a texture synchronously with the decoding (i figured sharing EGL context work can wait). I used multiple textures to implement some buffering.

So when I finally got it running (after wasting a good hour on a silly place-holder mistake when i started), it still suffers from the same problem. Along the way netbeans decided it had too many projects open, and the debug cycle time on the tablet seemed to get longer and longer.

Ho hum.

This morning I poked at using shared contexts, and although it seems to use less CPU time, it still crashes and it's doing something weird with the frame rendering order as well.

So yeah, might have to sit on this for a bit and brood.

Update: As one does ... I persevered. Current guess is that it's something to do with the texture load: if I isolate that out things seem to run fine (but with no repeatability this is hard to judge). More perseverance required.

Tagged android, hacking, java, jjmpeg.
Saturday, 05 May 2012, 03:35

Speaker-busting screech

So yeah, don't forget to set your endian-ness on your direct ByteBuffers when you're playing with sound files. Poor speaker. This morning I got sound going with jjmpeg/android. This was mostly fixing up the way I was using AVPacket's - I removed the the AVAudioPacket class and added the functionality to AVPacket. I need to look at the new audio_decode_4 api, as that might simplify the usage anyway and remove the need for the special case. I also hit some surround-sound files - i've just never played with audio much (don't even have speakers on my pc) - so have some more api to think about binding. Shouldn't be too hard to fit this into the video player, AudioTrack reports it's position which is enough.

Tagged android, hacking, jjmpeg.
Friday, 04 May 2012, 10:25

jjmpeg/Android

So yesterday I checked in the work I did last week for the android jjmpeg port. Not heavily tested, but it appears to work.

Then I spent far too long poking around trying to find out about the EGL OES_external_images extension, but finally came to the conclusion that it just isn't exposed publicly (yet?) so it's way more effort than it's worth to me to get it going.

So I suppose it's just glTexSubImage2D for me then.

GLES

I had a long work week this week and although I had intended to get a couple more things out of the way this morning I let it slide, and eventually got sucked in to playing with jjmpeg. I rigged up a version using GL, but still for now performing CPU-side colour conversion. I at least added a separate thread to do the colour conversion, and hooked it all up so that nothing needs to wait for anything else unless absolutely necessary.

The display stuff is a little bit faster - but nothing to worry about TBH. The colour conversion is only about 20% of the time, so it isn't a real big difference either.

I also tried with/without VFP: which made stuff all difference too, barely 5%. I started with 32-bit RGB textures simply because I had that already, and changed those to RGB565 which made another small difference. But all these small differences just weren't adding up to anything but a lot of small differences.

So anyway ... I went and looked at some of the options for skipping frames, multi-threaded decoding and what have you, and I noticed that threading wasn't enabled in the build.

Cut a long story short - beware of copies of copies of scripts one finds on the net: my compile script was basically shit. I also turned on NEON this time ...

Success!

I'm not sure if it's just the NEON, or the threads - or simply compiling it properly - but boy what a difference.

(actually it's all those not-so-little-bits now adding up, even single-threaded it's now much faster, in performance mode 2 threads can nearly handle 720p).

So it's now decoding 720p MP4 fine (taken from the on-board camera), even in 'balanced power saving' mode. Before it was struggling with this, under 10fps. And now the colour conversion is more like 50% of the time, so I will have to investigate using GLES for this since it should be a lot better at it.

Anyway, i'm quite chuffed at this now - I was starting to think it was pretty much pointless apart from perhaps encoding or more control over decoding. But this level of performance opens up a lot of possibilities. I'm also still only using ffmpeg 0.10.0 release, so there might be more there now too.

Update: So I kept going and added the GL colour conversion. Quite a bit better and 720p is fine with 2 threads, but not able to handle 1080P from the built-in camera.

Tagged android, hacking, java, jjmpeg.
Newer Posts | Older Posts
Copyright (C) 2019 Michael Zucchi, All Rights Reserved. Powered by gcc & me!