Thursday, May 29, 2014

avfs - Avisynth filesystem

The simpleslug pages mentioned AVFS. Tried it out. A 10 minute 2K planetarium show - Solar Quest - is seen as a 250 GB file after mounting. After Effects 4.1 complains error retrieving frame - not enough storage is available. But GL_warp2Avi works, even though it has the 2 GB file size limit for actual files, it seems to handle larger virtual avi files. Tested with 18 GB credits virtual avi file. 

Wednesday, May 28, 2014

replacing an acrilconvex mirror with a vialux mirror

From 2011, our fulldome projection has used an Acril Convex first surface spherical mirror. Last year, I'd purchased a used Vialux mirror. Today, we tried out the Vialux mirror, and decided to leave it installed for one show as a trial.

The Vialux mirror mini-review from Paul Bourke is here. As he notes, the extraneous reflections are more for the vialux mirror. The overall effect in the theatre is to reduce contrast and increase the brightness of the black levels. So we'll use the vialux only as a backup. Also did some back-of-the-envelope calculations of their radii of curvature.

After putting back the Acrilconvex mirror, I wonder if the perception of higher black levels was just an illusion. Maybe I'll try a light meter test next time, with a suitable frame on both mirrors. 

radius of curvature of spherical mirror

Did some back of the envelope calculations for the radius of curvature of our spherical mirrors, and with the help of the alternate segment theorem at this page, measuring x and y with a ruler got me r, the radius of curvature.

For the Acrilconvex mirror, 2x = 56 cm, y = 14.5 cm, so r = ( (28)^2 / 14.5 + 14.5 ) / 2 = 34.3 cm

For the Vialux mirror, 2x = 56 cm again, but y = 12 cm, so r = ( (28)^2 / 12 + 12 ) / 2 = 38.7 cm

Tuesday, May 27, 2014

simpleslug upscale

Checked out simpleslug upscale. Not directly useful for me, since the output is set to presets like 1080p 720p etc. Internally, it uses Blackman Resize, which is similar to, but better than Lanczos with higher number of taps. From this discussion linked on that page, it looks like sinc resize with avisynth might yield the best results for upscaling. But in our case, the loss of clarity seems to be more due to the codec used for the lo-res videos.

Update (2 June): As mentioned by the SimpleSlug author in the comments, was able to use simpleslug upscale with SimpleSlugUpscale(prog=true,outwidth=2048, outheight=2048)

As compared to doing Lanczos resize + Sharpen in Virtualdub below.

Monday, May 26, 2014

Software Bisque Seeker - docked windows, IMAGE

Found that starting Seeker with only one monitor leads to a docked visuals window. Starting Seeker with two monitors makes it un-docked.

Also, found that <IMAGE> does not render at all in fisheye mode. Directly changing <IMAGE> to <DOMEIMAGE> did not put the images in suitable positions.

Rendering of flat movie Explorers of Mars,

Rendering of dome movie of Explorers of Mars, with <IMAGE> changed to <DOMEIMAGE>

Sunday, May 25, 2014

Image Sequence Scanner

One of the many tools to check a sequence of images for corrupt or missing files - ISS or Image Sequence Scanner. But it does not detect errors in files like this bad frame,

why I removed ads

When I first started this blog, I had clicked through and added Adsense as Google recommended. But then, months of zero earnings later, I removed it, but did not post about it. According to this page, it's advisable not to put ads on your site if your traffic is below 10,000 page-views a month. Mine is only 1,400, so it really did not make sense to put ads on this blog. 

Thursday, May 22, 2014

resources from newtonscannon

Checking out the blog, found these useful resources:  has free samples.
compiz lighttwist plugin for blended large desktop. Could possibly be useful for blended two-projector dome setup?

Wednesday, May 21, 2014

some links for miscellaneous jobs

Hypercube Time Stretcher for stretching wav files to sync to video.

Stackoverflow discussion about how to map an ffmpeg frame to an opengl texture. for analyzing web page load speeds - and an old link to a test run in 2011.

Online tool for Hex color-code generation.

Frame-rate up-conversion virtualdub filter. Increase frame-rate by integer values - 2x, 3x and so on, interpolating frames.

The frame interpolation above could be used along with slow-motion for virtualdub ideas in this thread

Tuesday, May 20, 2014

more experiments with Software Bisque Seeker Theater Edition

More trials with Software Bisque Seeker Theater Edition:

  1. The About Seeker menu item and Solar System Map feature work when not in "Fulldome" mode, and when the flat screen version of "None" is selected in Settings -> Dome Projection.
  2. When writing scripts, leaving a space after the command tag and the first argument is a must. Wasted a lot of time wondering why <WAIT>20 was not working - it should be <WAIT>  20
  3.  <DOMEIMAGE> doesn't work with jpg files. Targa files as given in the example are fine.
  4.  <DOMEIMAGE> works best for small images - distorts panoramas etc.
  5. <QUIET> 0 makes not only sound effects, but also a counter of time elapsed while running scripts in flat screen mode - not in fulldome mode. 
  6. The spaceship movement seems to be auto-linked to the nearest object. 
As an example for the last point, after doing <WARP> "Earth" , using spaceship thrusters to move towards the moon and creating a waypoint there, when time is advanced, the camera and ship movement sync to make the moon centred. This is sometimes a problem, like when we want to make the moon move across the ecliptic. The moon as seen from earth is displayed too small to be visible in fulldome mode. But if we move close enough to the moon as to make it visible, camera and ship are no longer locked to earth, but are locked to the moon!

Also, access to the Software Bisque support forums are linked to the subscription. After one year subscription elapses, "Access Denied" to the support forums. In my case, "Access Denied" even 12 days before expiry of subscription. Can't even reply to my own bug-report post!

Thursday, May 15, 2014

Winebottler and Winamp on Mac

The Telugu team wanted to continue making playlists by dragging and dropping to Winamp, but move to Mac from Windows. I sent them the following options.

There is a "Winamp for Mac", but that has an interface similar to iTunes and not like Winamp. So, for a Winamp-like solution on Mac, there are various options:

1. Run virtualbox, run Windows inside virtualbox, run winamp in that window. Free software, but will take time to install windows, and will be slow.

2. Run Wine and Winamp on Wine. Free software, but takes hours to install, complicated installation.

3. Run CrossoverMac and Winamp using crossover. Software costs $16, we can download a 14 day trial, see if it works, and then pay if needed.

4. Installing WineBottler - and installing winamp inside it.

Apparently Winebottler 1.4 was already installed. Installing Winamp 5.5 inside it worked, but unfortunately drag and drop files into playlist was not working. Then they uninstalled Winebottler by simply dragging the app to trash, installed the latest version which was 1.7, installed Winamp 5.5 inside it, then it worked fine. 

Wednesday, May 14, 2014

cleanly removing applications from OS X

Looking for Winebottler drag and drop support (dragging and dropping from Finder to Winamp does not work), found this macrumors forum post about cleanly removing applications.

The steps include searching for the software by name in the default (Macintosh HD) volume, and expanding the search to include system files and hidden files. And then deleting them. 

Monday, May 12, 2014

transcoding older mov files

The Art Science Wonder mov file from was encoded with RLE codec. Directshow and Avidemux could not play it back, though it played back in VLC. To cleanly convert it to AVI with controlled bitrate, codec and resolution, finally used After Effects. My AE 4.1 was able to render it out as Xvid avi. 

Friday, May 09, 2014

mini-review of super-resolution filter

Tried out the Virtualdub filter for Super-Resolution from Infognition. The results did not seem to be very encouraging. Probably because the videos I tried had lots of motion in them, had compression artifacts and also lots of detail. 5x resize with Lanczos3 followed by Sharpen filter set to maximum sharpness seemed to have similar results to the Super-Resolution filter. And final result was quite inferior to the actual higher resolution image. All the sample images below were warped using GL_warp2Avi and are from the Citizen Sky - Epsilon Aurigae planetarium show.

Warped from a 2K domemaster:

Warped from a 640x640 video using Super-Resolution filter to resize 3x to 1920x1920:

Warped from the 640x640 video using Lanczos3 resize 3x followed by sharpen filter set to 25%:

Unfortunately the frames are not exactly the same. Also, blogger might be re-encoding the images. So the differences are not clearly seen. If you click on the images and see the original size, the comparison is a bit easier. 

The results using directly warping from the 640x640 video are clearly inferior to the results got from warping the lanczos3+sharpened frames. 

Warped directly from 640x640 video:

Warped after resizing 5x with Lanczos3 and then Sharpen 100%:

And finally, warped after 5x resized using the Super-Resolution filter.