SGI: Computer Graphics

hi everyone

hmmm was experementing a little with my O2 lately with image formats and this is what i notice.
.jpeg - loaded two halves at a time with a little delay which looks slow?
.sgi - loaded from bottom to top? or either way, with steps but a bit faster than jpeg
.pic - one time loading, very fast!

all formats uses the same picture with 1600x1024 resolution.

does it mean images using SOFTIMAGE format are fast to be rendered because it utilize the ICE? i thought JPEG should be faster coz O2 has a built-in for JPEGs? or its just for motion JPEG?

also, why did the native .sgi/.rgb format was slow compared to .pic from softimage?

sorry for this noob question

Not exactly sure but .sgi files I think are uncompressed, Jpeg uses complex compression algorithms and I am not sure about .pic but maybe it uses some simple compression like run length encoding and therefore is quick to unpack. Maybe the code that unpacks the .pic file was better written than the others... Other images have different information density and compress by different amounts. A sample set of just one image is not a good dataset to make comparisons about. Something that is all one colour will compress remarkably and uncompress formats might lose but something really complex with lots of colours might favor uncompressed format more.

lets say if .pic was fast with imgview, is it safe to say if i compile a movie out of .pic images, it would be faster than a movie compose of jpegs or rgb images?

my purpose for this test is to find which things utilize the ICE of the O2, i use Ian's melting the ICE as reference

lets say if .pic was fast with imgview, is it safe to say if i compile a movie out of .pic images, it would be faster than a movie compose of jpegs or rgb images?

Not sure of the question but probably faster as the sum of all parts equals the speed of the whole but then it probably depends on other things like how the images are combined, I don't have the source code and I am not even sure how it is meant to work.

i want to try to play a mjpeg movie but unfortunately i couldn't find a movie in that format. tried to find converter for WinXP but its output is not supported.

The O2 VICE was designed to process standard definition video in real time. If your images are bigger than this then it will take longer to decompress. From memory, the VICE supported MJPEG, h.261, and DV/DVCPRO. MJPEG is just a stream of frames, each individually compressed with JPEG.

In order to take advantage of VICE you need to use SGIs DM APIs. I seem to remember that not all the supplied SGI tools supported everything in every version but I might be mistaken. Check that the tools you are using take advantage of VICE when it's available.

You seem to have found Ian's "Melting the ICE" page which supports some of my recollections: he mentions that dmconvert doesn't always take full advantage of VICE but he doesn't mention DV/DVCPRO support.
However, it is mentioned here: http://www.futuretech.blinkenlights.nl/o2/2145.pdf


You may also want to have a look at:
+ http://www.futuretech.blinkenlights.nl/o2arch.html#ICE
+ http://www.futuretech.blinkenlights.nl/ice.html (Melting the ICE)
+ http://www.futuretech.blinkenlights.nl/o2/
+ viewtopic.php?f=16&t=15285
+ http://techpubs.sgi.com/library/tpl/cgi ... z&srch=ice
+ http://www.nekochan.net/wiki/O2#O2_Video_System

Regards,
@ndy

Hi,
You might like to check out ffmpeg (I'm not sure what the builds for Windows are like). Be careful tho': to be useful with VICE you need to ensure that you use an SGI compatible version of MJPEG.

Have you got the AV card for your O2? If so it's probably easiest to plug a video source into that and capture it: that way it'll be in the correct format. (The VICE can encode MJPEG as well as decode it. I think there was both realtime encoding and decoding for a lot of the codecs, except DV which was never publically released; most DV comes in via IEEE1394 where it's already encoded.)


Regards,
@ndy

the reason why i dig about this is i want to make a converter in my PC side. Convert any movie file into a playable movie file in my O2 coz waaah most movies i downloaded to my O2 really slow or even will hang-up really strange i cannot play movies using mplayer.. mediaplayer only few files. even the avi's i got it will complain. i try the divx player by hmm forgot his name, also didn't work..

Hi,



You might like to check out ffmpeg (I'm not sure what the builds for Windows are like). Be careful tho': to be useful with VICE you need to ensure that you use an SGI compatible version of MJPEG.

Have you got the AV card for your O2? If so it's probably easiest to plug a video source into that and capture it: that way it'll be in the correct format. (The VICE can encode MJPEG as well as decode it. I think there was both realtime encoding and decoding for a lot of the codecs, except DV which was never publically released; most DV comes in via IEEE1394 where it's already encoded.)


Regards,
@ndy

No I did not write that.

Hi,



Ah... Now I understand more about your objectives. Try encoding on the PC side to DV. I imagine that it'll be easier than working out the esoteric MJPEG options and the quality will be higher. If the disk on your O2 can sustain 4MB/s then VICE should be able to play that file in realtime. Lots of PC video editing software knows how to export in DV.


Regards,
@ndy

Hi,



Oops... Sorry. I must have had an editor error.


Regards,
@ndy

tonight is the start of cold winter here in my location..

Yeah, it drops down below 70 sometimes ...

... this CNY ill go to Henan to my girls hometown and christmas just here in shenzhen ... ^^)

You realize if she's taking you to meet the parents then you're going to get married ? I'm serious. You should probably not do that unless you are willing to take her for life.

On this occasion I am not being humorous ... you are playing with fire.