World: r3wp
[Postscript] Emitting Postscript from REBOL
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Henrik 24-Feb-2008 [1432x2] | wow, that took a long time to generate. |
but it works | |
Geomol 24-Feb-2008 [1434] | ! Great! :) |
Henrik 24-Feb-2008 [1435x2] | 15 seconds at 100% CPU |
when adding DeviceRGB in your previous example, that example works too. | |
Geomol 24-Feb-2008 [1437] | Maybe because it had to load image from web also!? Try with a local version of the image. |
Henrik 24-Feb-2008 [1438] | and that took less than 1 second to generate. |
Geomol 24-Feb-2008 [1439] | cool |
Henrik 24-Feb-2008 [1440] | well, it would be bad if it ate that much CPU, just waiting for network stuff. |
Geomol 24-Feb-2008 [1441x2] | I load the image with load-image/update to be sure to always get latest version. |
Maybe your system had a hickup? Try again! | |
Henrik 24-Feb-2008 [1443] | tried several times, same result. |
Geomol 24-Feb-2008 [1444] | ok |
Henrik 24-Feb-2008 [1445] | will test with a local file soon |
Geomol 24-Feb-2008 [1446] | Try take a local copy of postscript.r and change the load-image to not do a /update. |
Henrik 24-Feb-2008 [1447x4] | writing palms.jpg locally took 1 second |
testing postscript generation | |
perhaps 12 seconds with a local palms.jpg file | |
what do you do to translate the data? is it in mezzanine form? | |
Geomol 24-Feb-2008 [1451x2] | Images are implemented in postscript.r using ASCIIHexDecode filter, which double the size of image data. It would be better to implement ASCII85, which does a 4:5 increase only. Also images are handled in something called dictionaries in PostScript. This require PostScript v. 2.0. |
If you look in postscript.r, I encode the image data in line 211-220. It's just normal hex written as ASCII, so you get '0'-'9' + 'A'-'F'. | |
Henrik 24-Feb-2008 [1453x2] | when building the image data, how do you do that? or does ASCIIHexDecode do that? |
ok | |
Geomol 24-Feb-2008 [1455] | So this is very simple encoding. ASCII85 encoding is a bit more difficult, but will take up less space. |
Henrik 24-Feb-2008 [1456x3] | perhaps it's equal in speed, I don't know. odd though, I can't see what's so slow about that code, other than the newline insertion thing |
perhaps inserting in images is very slow? | |
does it need to be done? | |
Geomol 24-Feb-2008 [1459x2] | It seems to work without the newlines, but then the ps file become difficult to enter with e.g. vim. That part is fast, I think. It only put in a newline for every 80 chars. |
My guess is, that it's the load-image/update that give you performance hit. Try change it! | |
Henrik 24-Feb-2008 [1461x3] | it does not, I tried a local file. 12 seconds. |
will try to add some profiling hints | |
nope, it's the inserting part. the rest is taking no time at all. | |
Geomol 24-Feb-2008 [1464] | You say, you tried a local file, but did you change the load-image in postscript.r? |
Henrik 24-Feb-2008 [1465] | so I think there should be an option to leave that out, or by default not have it. I'm guessing most people want to generate and print PS file, rather than read and edit them by hand. |
Geomol 24-Feb-2008 [1466] | ok, the inserting of the newlines is the problem? |
Henrik 24-Feb-2008 [1467x2] | didn't try that with /update yet. will have to be sure |
yep, same thing without /update. | |
Geomol 24-Feb-2008 [1469] | If the inserting is the problem, then I might be able to fix that with copy to another series in stead. Problem with insert is, when you have large series, it has to move the content down the memory. |
Henrik 24-Feb-2008 [1470x2] | I'm trying to remove that code right now to see if it improves performance. |
now GS won't read the PS file, but the generation is much much faster. less than 0.5 secs | |
Geomol 24-Feb-2008 [1472] | Just uncomment after the trim in line 213. |
Henrik 24-Feb-2008 [1473] | did that |
Geomol 24-Feb-2008 [1474x3] | ok :) |
Ok, I'll see, if I can make a faster insert... | |
Henrik, try with new version now: http://home.tiscali.dk/john.niclasen/postscript/postscript.r | |
Henrik 24-Feb-2008 [1477x4] | odd, GS won't eat it |
oh, error 40 :-) | |
much faster now and it works | |
tried a much bigger image. no problems at all. | |
Geomol 24-Feb-2008 [1481] | Great! That's the version to use for now then. Maybe I should put an announce in that group? |
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