FORUMS: list search recent posts

--- Odd & Low Horiz/Vert Resolutions of .PNG Exports from PI-3

COW Forums : particle Illusion

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
Soniclight
--- Odd & Low Horiz/Vert Resolutions of .PNG Exports from PI-3
on Apr 21, 2007 at 2:38:53 am

Odd & Low Horiz/Vert Resolutions of .PNG Exports from PI-3

I use Sony Vegas as an NLE and usually export the particle effects as non-intense alpha .PNG sequences so I can fine tune things. I often have to double up (stack) two of the sequences to get a crisper, brighter look to these files in Vegas. They can appear a bit fuzzy or washed out.

Then I happened to look at the resolution of one frame (from one sequences getting close to HD image size) at random -- and maybe this is why the quality is poor overall:

Image size: 999 x 678
Resolution:
-- Horizontal - 52 dpi
-- Vertical - 20 dpi

That's very low, way below basic screen 72 dpi -- and it seems to me that it should be proportional (same for horizontal and vertical). Larger image sizes seem to just mirror this odd and low ratio proportionally: more .dpi but still way too low IMO.

Am I missing something here, is there a way to fix this?
Thanks


Return to posts index

Soniclight
Re: --- Odd & Low Horiz/Vert Resolutions of .PNG >>> Need Support Reply PLZ
on Apr 22, 2007 at 3:05:10 am

... When you PI wizard guys settle back in from NAB and/or this weekend, etc. Thanks :)


Return to posts index

Alan Lorence
Re: --- Odd & Low Horiz/Vert Resolutions of .PNG Exports from PI-3
on Apr 23, 2007 at 10:46:56 pm

Do you mean that these are the DPI values being reported in the image files produced? If so, switch to creating TGA in pI3 and see if that helps.

There's a bug in pI3 for Windows that doesn't set the DPI value, so image formats that use it are getting "garbage" values there.



Alan.

http://www.wondertouch.com


Return to posts index


Soniclight
Re: --- Odd & Low Horiz/Vert Resolutions of .PNG Exports from PI-3
on Apr 24, 2007 at 11:29:23 am

OK, thanks for reply. I tried TGA (a format I never worked with so far, but it isn't working out even though I exported with non-intense alpha and remove-black from alpha.

To illustrate the results, I have created a generic temporary page for this issue with brief annotation at my website with screenshots of the identical frame of a test export sequence:

-- In PI-3 (minus background image to show what the particles should look like).
-- As PNG - with Gimp* image info
-- AS TGA - with Gimp* image info.

I have also included the actual 1024x768 PNG and TGA frames (see why below).

Please note that this temp page will not be up indefinitely (so as not to clutter up the website's directories).
It shows that:

--- The PNG came out accurate, but still in seemingly disproportionate 64.9986 by 24.003 dpi resolution. The TGA looks terrible (like an alpha-masked PNG but seemingly without the mask) but the resolution is OK.

Resolutions info is according to Gimp stats which is Windows based. But if the PNG res info is gibberish according to what you said, then...

... What is its actual resolution (and that of all PNGs exported from PI-3)?

Which is the reason I have included save-links to the actual PNG and TGA frame versions at the bottom of the page for you to copy/save and inspect for yourself (and tell me what res you get).

The TGA one is uncompressed, which may be best for this support Q situation since it looks odd/mask-like even in uncompressed format.

_______________________

Last, before posting this, I double-checked that the Project Settings and Preferences matched in frame rate and size (640x480, NTSC 29.97). One was at 30 fps and res was too low on the other, so I corrected and re-rendered new PNG and TGA.

The results were identical, as were each file's info stats, and so I left the first set of exported files at said page. I don't see it as a project settings problem.

All that said, I'm probably missing something pretty obvious here. Thanks for any assistance/suggestions regarding this issue.

http://www.compassionsensuality.net/PI_TEMP.html


* (I can't open TGA in PhotoPaint 12 which is my core stills/digital image app, so used Gimp. I studied PhotoShop in school, I can't afford it, but PP has served me well 99% of the time.)



Return to posts index

Soniclight
Re: --- Odd & Low Horiz/Vert Resolutions of .PNG Exports from PI-3
on Apr 24, 2007 at 11:36:42 am

As you may have noticed, something went wrong with the link to the temp page in my posting above.
Please use this one. Thanks.

http://www.compassionsensuality.net/PI_TEMP.html


Return to posts index

Alan Lorence
Re: --- Odd & Low Horiz/Vert Resolutions of .PNG Exports from PI-3
on Apr 24, 2007 at 12:16:50 pm

The TGA file is fine, believe it or not. The difference is in the viewing -- Gimp in this case, or possibly in the options you used when rendering in pI3.

The TGA image shows that you used the "remove black..." alpha option, but are not displaying the alpha channel in Gimp. This doesn't mean that the alpha channel is not there.

To check that the alpha is really there, bring the rendered image into pI3 as background footage for a layer, then make the background color non-black.



Alan.

http://www.wondertouch.com


Return to posts index


Soniclight
Re: --- Staying with.PNGs & Image Improvement
on Apr 25, 2007 at 2:40:25 am

Thanks, Alan. I did as you suggested and the non-black background showed through fine in PI.

Solving The Non-Issue (Stay with PNG)?

But as stated in an annotation on the temp page, Vegas shows the same "masked" TGA in a track as Gimp does. I could make and upload screenshots of one track with the PNG, the other with the TGA to show this but it's pretty self-explanatory.

I'm going to probably post a Q about this at the Vegas forum. However...

Maybe it's not necessary and I can just continue to use PNG -- if you can put this issue to rest:

--- Having given you actual frames in each version to check out (both versions show exact same 1280 x 786 pixels) -- is it not this file info the matters -- and not the accurate or inaccurate dpi ones since this isn't for hard copy printing)?

Meaning that the PNG are OK as-is (pixel info does reflect export stage and percentage size) and I've been freaking out over irrelevant file data.
If so, my apologies for this much-to-do-about-nothing, but it's part of the learning curve of working in multimedia.

That said...

Improving Image Quality of PNGs For/In an NLE

As far as the at times fuzzy look of PNGs in Vegas that prompted this Q, doubling up isn't so bad for I can adjust the composite levels and get a decent feel and look.

What I do in PI to maximize quality/resolution:

--- I switch to the largest screen resolution my system can handle and let the stage take up as much desk real estate as possible when exporting from PI. (The exception was the files I rendered for this Q since I want to save disk space -- I used regular non-editing screen res.)

The only problem is that I usually have to add a bit of sharpen in Vegas post: this has the downside of making them a bit edgy or crackly, especially when rendered as .WMV or other highly compressed format.

Suggestions welcomed on any other improvement tips, be it in PI or post in Vegas. Thanks.



Return to posts index

Alan Lorence
Re: --- Staying with.PNGs & Image Improvement
on Apr 25, 2007 at 12:08:19 pm

The DPI information is not used by most programs from what I understand, so it's probably not an issue. I do wonder about the "fuzziness" that you mention though.

Do you see this in particleIllusion itself? The only thing I can think of is that you're scaling up too much, and probably need to create some higher-res particle shape images.



Alan.

http://www.wondertouch.com


Return to posts index

Soniclight
Re: --- Staying with.PNGs & Image Improvement
on Apr 25, 2007 at 7:01:28 pm

You're probably right about the scaling regarding so-called fuzziness. It also most likely depends on the type of emitters used: I tend to go for the more misty, subtle and sparky types.

There is also the element of perhaps expecting ILM production level stuff due to the excitement of being able to create such magic "at home" on one's computer.

PI-3 is really great, but it's one application, not 100 workstations pumping out fx on Lucas's ranch :) It offers the little people like me and any creative one-man-production endeavor the chance to do some amazing things.

As with any situation, one works with both the limitations and the advantages. I'm thrilled to have PI-3 and will just learn to adapt and fine-tune.

... So watch out, George Lucas. We PI people may not have your fancy digs. But we've got our own magical wizardry up our sleeves -- and may just surprise and blow you with what we can do :)

NRN.


Return to posts index


Soniclight
Re: --- LucasFilms Hardware vs.my PI-3 on Pentium D :)
on Apr 25, 2007 at 8:23:41 pm

Ahem, maybe I was overshooting a bit on competing with Lucas hardware. According to recent BBC article:
"LucasFilm is powered by a data centre equivalent to 10,000 home PCs with 250 terabytes of storage."

But I'll keep working at it - lol


Return to posts index

<< PREVIOUS   •   VIEW ALL   •   PRINT   •   NEXT >>
© 2017 CreativeCOW.net All Rights Reserved
[TOP]