Saturday, March 26, 2011

error while importing files into database

When I ran our usual main_ftp script to import audio files to local database, it gave a strange error:
/home/sgh/scripts/question: error while loading shared libraries: cannot open shared object file: No such file or directory
and the same message repeated on and on kept scrolling. Later, realized that three of the files were wav files instead of mp3, that had triggered the errors! Removed the wav files, replaced with mp3 files, all fine.

Thursday, March 24, 2011

problems during first fulldome show

So we had our first fulldome show - two shows actually. The problems we faced were:

  1. projector doesn't switch off with remote - have to lean around to switch off using the button on the unit. Another workaround is to change the input to another non-active input and then power off.

  2. avs files give error on first try, intermittently - this seems to be because the machine and or hard disk cannot keep up. Solution is probably to render the AVISynth files as avi files.

  3. alignment may be improved - probably increasing the height of the mirror might help to reduce the height of the horizon at the front of the dome, by increasing the angle of tilt of projection.

Another innovation would be to remove the need for the 110V system altogether - currently used only for lighting - by using the video projector itself for lighting. Still frames like the one below, made into movies with AVISynth.

Tuesday, March 22, 2011

avisynth and virtualdub for fulldome show

After warping with tgawarper, and rendering with virtualdub to make a movie, decided to do non-destructive edits with avisynth for making the credit appear at the beginning (so that the audience wouldn't walk out during the end credits!) and for the intro and outro videos. For the intro and outro videos, it turned out that taking 4:3 video as the source, I could just make the video occupy a 640x480 rectangle near the bottom of the 1920x1080 screen, and it would come out reasonably well though much enlarged when reflected with the mirrordome. This conclusion was reached after much trial and error using the General Quadrilateral Transform filter from here. The settings were as follows:

1000 - 520 = 480 and so on.

Except for simple FadeOut and Trim commands, the intro video was relatively straightforward. The show video itself had some extras, including a subtitle call for adding the Indian voices to the credits. The file was as below:


Trim(mix,0, 3085)
++ subtitle(Trim(mix,39024,40504), "Indian voices: K, A, V", -1, 1000, align=2, 651, 699)
++ FadeOut(Trim(mix,3116, 37816),60)

The last line being actually on a single line with all the ++ etc. The outro also had some gymnastics because of an extra line of audio I wanted added. This was before the Virtualdub quadrilateral transformation:
blank=BlankClip(video,length=750, color=$000000)
video_pre=AudioDub(blank, blankaudio)
video_pre ++ video

Finally, all the three - intro, outro and the show itself - were put in a KMPlayer playlist, a .KPL file.

Friday, March 18, 2011

MediaWarp3​D evaluation

Tried out MediaWarp3D - had been in touch with one of the guys involved in developing it. Priced at $995. On my machine - Athlon X2 Dual core at 1.9 GHz, 2.75 GB RAM, nVidia GeForce 9100 M G - only one of the two windows could be running for a full fps Real-Time Warping. If both windows were open, drops to 15 fps or so. Has options for 3D, but since I neither have the hardware nor the content, couldn't test the 3D part. A screenshot is here.

rate of sending emails

This morning, there was a gateway mixup - the SMTP firewall rule was pointing to a disabled gateway, so the emails did not go through. After I changed it, checking the number of mails pending with sudo qshape incoming active deferred found that the mails were going at the rate of approximately 20,000 per hour. Of course, services like yahoo which had rate limiting would queer the pitch, but otherwise this was the rate for a 1 Mbps line, I believe.

Wednesday, March 16, 2011

bat file to start IMs

Going offline in three chat apps and coming back online later was a bit of a pain. So, exiting them instead, and made a bat file to start all three of them at once. But for running Windows apps in a BAT file, and to continue execution (similar to putting a task in the background on *nix) the syntax is:

migrating mail from GMail to Google Apps and so on

While discussing the sssihl migration, where they have an edu GApps account and hence can use GApps IMAP migration tool, S mentioned that some other institutions like MedTrust had similar requirements. But they're using the Standard (Free) Edition.

For just a single account to another account, the migration would be possible, though slow, by just adding both accounts as IMAP accounts on a desktop client like thunderbird, making sure that emails are retrieved completely and not only headers, and dragging and dropping from one account to the other, as given in this discussion.

In the link above, the popular answer is the way it's being done with the IMAP migration tool on the Edu version. But the lifehacker link just below that gives this other method.

Tuesday, March 15, 2011

transferring files to a Nokia phone

N wanted me to transfer some mp3s to a Nokia music phone. First try with the data card directly inserted into the card reader did not work - probably because the card reader can't read high density SD cards or something like that. Then tried by connecting the phone via usb and using Nokia Phone browser. That opened up Windows Media Player, and asked it to transfer files. But when we attempted to transfer, it would say "An error occurred". Finally got the job done by transferring to my SD card, then transferring from my phone to the Nokia via bluetooth. One future possibility is attempting through Nokia PC suite.

Thursday, March 10, 2011

phplist attachment size limit

There were issues with the shared internet connection being swamped by the Sai Inspires emails, especially when they were sent late. P wanted me to set an attachment size limit in phplist, so that the email attachment would be 20 kB instead of 100 kB as was done recently. Went through the docs, did not find any such parameter in phplist except setting file upload limit for php itself, as given at this post.

Since the upload_max_filesize attribute is of php itself, not of phplist, I was afraid of breaking things if I set it in php.ini, so did not do so. Instead, the current solution is to not embed images at all inline, and to just link them instead as in Sai Spiritual Showers. A link to the online version makes it easier for the 'linked image challenged' email clients.

changing virtual postfix hosts and testing SMTP with telnet

As given in my earlier post, the only change required was to change the line
virtual_alias_domains =
in /etc/postfix/ and accordingly make changes in /etc/postfix/virtual running
sudo postfix reload
sudo postmap virtual
afterwards. Actually I ran the postfix reload after the postmap also, just to be sure. For testing, using telnet as given in this technet article, telnet on port 25 to our machine failed from dreamhost. Tried restarting the network, firewall box, etc, but probably dreamhost has blocked port 25 for spam-blocking. Restarting network was
sudo /etc/init.d/networking restart
by the way. Finally tried it from our colinux machine, there it was working fine.

telnet 25
Connected to
Escape character is '^]'.
220 ESMTP Postfix
250 2.1.0 Ok
250 2.1.5 Ok
354 End data with .
Subject:2nd test
One more test email.
250 2.0.0 Ok: queued as 491ID14E8EC
telnet> quit

Wednesday, March 09, 2011

backing up phone contacts

I've not tried them myself, but A at the Studio said these were good:

1. Google Sync for your phone
(this one seems to have moved to

deleting a gateway in Cyberoam

Our ISP changed, and suddenly I had to delete a gateway on the Cyberoam which was no longer active. With the gateway still existing, the device was unstable and not allowing incoming connections. First took a backup as P advised, System -> Manage Data -> Backup Data. Then, going directly to System -> Gateway -> Manage Gateways and trying to delete it gave the error message
Gateway used for pool(s) or Acting as Effective Gatway or assigned to firewall
rule cannot be deleted
So I went to Firewall -> Manage Firewall and removed all the firewall rules relating to virtual hosts which mentioned that gateway. Still no dice. Then removed those virtual hosts too. Still no. Then removed the relevant host names from Firewall -> Host -> Manage. Still no. Then, during a support chat with Tech support, thought about other firewall rules, outgoing rules for eg. Lan to Wan and so on. Went through those, in a couple of them the old gateway was the Primary. Modified the rules suitably, then the gateway could be deleted.

Friday, March 04, 2011

ip address change and cyberoam changes needed

After getting a new IP address and a new ISP, did the following changes to cyberoam.

1. Delete firewall rules using the relevant virtual host(s) which reference the old ISP ip addresses etc. For this, you have to go through all the firewall rules - even things like DMZ-DMZ etc.
2. Delete the relevant virtual host.
3. Create the corrected virtual host - basically only the External ip address changes.
4. Make the firewall rules again! Here, things like DMZ-DMZ rules are made automatically, when the WAN-DMZ rules are made.
5. Modify host group (if any) to add the new ips. We had the group of machines which were allowed to ssh. For this, first create a relevant host name, and add it to the group while creating it.

All these changes took around half an hour.

Later I had to change the ip addresses pointing to the web server and so on.

Edit: After 24 hours, learnt from experience :( that I should have updated the spf txt dns records before-hand! All gmail emails went to spam. Anyway, I have done so now...