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You aware of the IE bug in the forums too? Every time it renders a page in the forums it hangs for a couple of seconds and grabs all the CPU time, even if you’re just flipping back and forth with no network activity. Happens in IE6 and in the new IE7 beta too. I guess it’s a bug in IE, it’s fine in everything else 🙂
Also, would be good if the “view posts since your last visit” thing worked, it always tells me no posts matched my search criterea.
You don’t nessecarily lose information. If you go from 4:4:4 RGB to 4:4:4 YCbCr in 10 bit or higher I defy anyone to see any visual difference 🙂 Even in 8 bit, well, you can try with those Sparks I posted in the Effects forum – chain a whole bunch together in Batch, nothing much happens.
Technically yeah, YCbCr is a much larger colour space so you have poorer symbol utilisation so you add quantisation noise when you convert to it, but not, like, much 🙂
It’s the chroma subsampling that does the real damage.
Trying holding the spacebar and dragging. I don’t know, I’ve never used Fusion, but this works in everything else 🙂
Installing Irix is serious fun. If you have the little booklet that comes with the CDs, that will tell you how to boot sash and fx off the first Overlay CD, to partition the disk.
It might well be in one of the Discreet manuals too.
Otherwise Ian Mapleson’s site has a great load of Irix info, here’s an install guide with the info you need: http://www.futuretech.blinkenlights.nl/6.5inst.html
Good luck: I would set aside like a whole day to get Irix and Flame installed from CDs and working as I like. Irix comes on so many frickin’ CDs (15 in my set and I’ve lost one!) that I’ve copied them all to a hard disk to make things go faster 🙂
Subsampling patterns are explained here but I guess there are better explanations around. It just means the “brightness” is stored with higher resolution than the “colour” part in various different and not terribly important ways.
As well as chroma subsampling like that, HDV also compresses the entire picture fairly drastically, so yes, the luminance channel is compressed.
Sorry, I edited my last post after you replied. Do those little LEDs tell you anything?
If the monitor syncs I guess the GFX is okay.. the next step is trying a serial console but that’s a bit scary 😯
If you don’t even get a PROM screen then something more than the disk is wrong… try taking all the disks out and booting, you should still get a PROM screen, and then an error when it can’t find anything to boot from.
What colour is the lightbar on the front? Does it stay red, or turn white, or blink or anything?
Is the monitor even syncing? If not, maybe the graphics board got joggled whilst changing disks? You could try taking it out and reinserting it, but be very careful of the weirdo connectors which look like a grid of gold dots… do not touch them! A common problem with old Octanes is dust getting in these connectors. You can clean them with canned air if you’re careful… instructions in Appendix B of this: stupid long URL
If not that, it could be the same thing on the mainboard which is on the other side. That one has two connectors. You might be able to tell what’s up by looking at the green LEDs you can see at bottom left of the front with the skin off… details here: Another stupid long URL
Fixing Octanes is fun 🙂
YES! Well I think so. I love screen captures. Possibly just because I’m an interface and usability geek though.
FLGB wrote:DV and HDV share the same data rate (25mbps) HDV compression ratio is around 22:1 (Mpeg 2 which is harder to edit and requires a lot of cpu power) while DV is “only” 5:1 (using jpeg compression).Weellll, DV isn’t actually JPEG, it’s more clever and more suited to video. And MPEG2 on its own should need less CPU power, but you’re right that when you start needing to edit or even just seek and scrub in it it becomes a pain in the ass and slows right down. Final Cut Pro 5 has fully native HDV support, maybe it’s easier now? Anyone used it?
I’m just nitpicking here, it’s all good advice 🙂
Combustion 4’s 3D DOF operator… I was playing with this the other day and it seemed to be completely sucking. Is it me or does it just blur within the range you give it, and nothing at all outside that range? I got much better results with Compound Blur, using a CC operator on the Z and the histogram to set the range and falloff.
Also, does the G-Buffer DOF one correctly handle things like sharp distance objects showing through blurred edges of closer ones which you’d get with true 3D or real-world defocussing?
Pleased to hear it 🙂
Storage is what you want to think about first for an uncompressed machine, the rest is just icing 🙂
RGB to YCbCr using CC and Actions nodes is easy enough but I’d forgotten what a pain in the arse doing the inverse is… you run into all kinds of nasty issues with clamping and negative numbers and quantisation. Last time I did this it was in a pixel shader in floating point which was a lot easier.
Anyway here’s the setups to do the RGB->YUV part: http://lewissaunders.com/ycbcr/ycbcrBatch.tar.gz. Hopefully it makes some kind of sense… CC nodes do the Seperate part, the matrix multiplication (basically) is done by Action nodes with Simple Add and Subtract transfer modes and transparency. The half_grey node in there is for adding 0.5.
And since I failed to complete the second half of the colourspace conversion playground laboratory OF DOOM, I wrote RGB->YUV and YUV->RGB sparks which work in Batch, you can get them here: http://lewissaunders.com/ycbcr/colourspaceSparks.tar.gz. They work fine but the usual arse-covering disclaimer applies 🙂 There’s 32- and 64-bit binaries for Irix and the source too. Enjoy!
What file format are the images in? Z-buffers work best with lots of precision, like 24 bits for the single channel, maybe your 3D app has written it in a weird format?
Someone correct me if I’m wrong, but I think the only HDR formats Combustion will read are OpenEXR, RLA and RPF?
That’s only on the NTSC version, isn’t it? I think the PAL version shoots in 50i or true 25p only?