Sunday, October 20, 2013

VLC-based Warp-on-the-fly player from Paul Bourke - mini review

Paul has now released the VLC-based Warp-on-the-fly player. Here was my mini-review for the beta test done on Oct 4.

As Paul mentions, there are some performance issues. Relatively low bitrate / lower resolution files are OK. The sample1.mov file  - 1280x1280, 6.4 Mbps with avc1 codec - plays smoothly. A 2K file I encoded with Xvid codec, 9.8 Mbps, plays at something like 15 fps, with more frames being dropped where the scenes are more complex. Seems to be CPU limited in my case, so people with beefier CPUs should be OK. Mine is an Athlon 64 X2 dual core processor at 1.9 GHz, with Nvidia Geforce 9100 M Graphics.
CPU usage -

1280x1280, 6.4 Mbps with avc1 codec with warp - 55% with beginning peak of 75%

1280x1280, 6.4 Mbps with avc1 codec without warp - 40%

2048 x 2048 Xvid codec, 9.8 Mbps with warp - hits 99, 100%, hence frames dropped to 15 fps or so.

2048 x 2048 Xvid codec, 9.8 Mbps without warp - 65%, with peaks of 75% for complex scenes.

Another issue for me is that the snapshot feature, or the convert feature, does not capture the warped file, but instead captures the input frame. Perhaps there is some setting which I should do in order to capture / export the warped frames from this player? If I can get the capture / export working, then the performance issues will be moot......

Sureyyasoft Shira Player mini review

Tried out the Shira Player from Sureyyasoft - a player modified from a Stellarium base. At first it crashed, the developer sent me a shader file to put in the data folder, after which it works. Interestingly, it does on the fly warping of fisheye movies using the spheric mirror distortion built into Stellarium. But as mentioned in my previous post on Stellarium, the output image quality when warped is not so great, especially when I use image capture and compare with the other warping tools.

Image obtained from the avisynth plugin, using Flipvertical():

Image obtained from Shiraplayer:


Additionally, there seems to be some sort of up-down flipping involved: Flipvertical() was used in the avisynth script to get a similar image.

Update: Newer version of Shiraplayer with these issues solved, discussed here.

Saturday, October 19, 2013

infection on Studio network

Our IP address was blacklisted on the CBL due to an infection of one of the machines. Apparently CBL detected a trojan on our network, trying to connect to other machines via UDP. So, even though our network was not sending spam, CBL blacklisted the ip address. 

First, PB changed the IP address of outgoing http and connections other than mail, to another ip address which he had available. Then, CBL blacklisted the new ip, with the additional info that no spam was detected, only the presence of the trojan:

IP Address x.y.z.a is listed in the CBL. It appears to be infected with a spam sending trojan, proxy or some other form of botnet.
It was last detected at 2013-10-17 11:00 GMT (+/- 30 minutes), approximately 16 hours, 30 minutes ago.
This IP address is infected with, or is NATting for a machine infected with the ZeroAccess botnet, also known as Sirefef. More information can be found from Wikipedia. It is most often used for bitcoin mining or click fraud, but as it contains a downloader portion, it can do anything.
If this IP address is a NAT gateway, it should be possible to find which computer on your internal network is infected by implementing a filter on your firewall to detect and log attempts to send UDP packets to the Internet with a destination port number of 16471. 

In Cyberoam, System -> Diagnostics -> Connection List tab,  port number of 16471 was seen in the destination section. That machine was cleaned up using Norton Power Eraser as recommended by CBL. Issue resolved for now.

Thursday, October 10, 2013

beware of distributed brute-forcing

An interesting article about distributed brute-forcing by bad guys - 

https://bsdly.blogspot.com/2013/10/the-hail-mary-cloud-and-lessons-learned.html

So, for SSH we can use key-based auth for protection, and it would be safer to use two-factor auth for other things like wordpress.

Wednesday, October 09, 2013

connecting to our ssh server via mobile internet

Due to various power outage issues in the region, I've had to fall back on ConnectBot to connect to our servers. The ip addresses for Airtel 2G seem to be all over the place, as given at https://as.robtex.com/as45609.html#bgp

So, instead of white-listing all the ip ranges 106.0.0.0/8, 223.0.0.0/8, 27.0.0.0/8, 171.0.0.0/8, 182.0.0.0/8, and so on, just added our Voxel server's key to authorized_keys, and added its ip to the allowed range.

Took me an extra ten minutes to do this. First,
host media.radiosai.org
gave me the wrong ip address to allow - the Cloudflare CDN's ip address! Then, the copy-paste of the id_rsa.pub added newlines, so I got errors like error: key_from_blob: can't read
as seen in /var/log/messages of the server. Removed the unnecessary newlines, got it working - there is no need to restart sshd when adding keys. 

Monday, October 07, 2013

saiwaves not booting - manual boot choice needed

With all the power issues we face, we've had to shutdown our servers quite a number of times. saiwaves refused to come up - and the following was PB's solution.

These links helped....



use F11 - Boot Menu  
In the boot menu select Hard Drive C: 
then select Slot 2 (Virtual Disk)

Saturday, October 05, 2013

Cloudflare optimizations break javascript

Our web-based audio player seemed to have broken all of a sudden. Strange symptoms - working on Safari, but not on Chrome or IE or Firefox. Checking the source, found some Cloudflare injected code. Tried pausing cloudflare, that solved the issue. Then found that Cloudflare optimizations are known to break javascript, jquery and so on. Turned off optimizations, made the settings CDN only, modified the rules for media.radiosai.org also to omit the optimizations, then all is well.

The search box on every page of radiosai.org also had broken due to the javascript issues - removing Cloudflare optimizations solved that issue also. 

Friday, October 04, 2013

saving a video with effects applied via vlc

In my previous post, I failed to save a video with effects. But now, this page showed me how to do it. The gui-based method is:

  1. Show all settings (and not Simple) from Tools -> Preferences -> Interface settings
  2. In Preferences, under Stream Output -> Sout -> Transcode, choose appropriate filter
  3. From main menu, Media -> Convert/Save
  4. Add input files, and choose Convert at bottom convert/save drop-down.
  5. After doing required conversion, Tools -> Preferences -> Reset Preferences
Unfortunately, this method did not work out of the box with the vlc-based warp player made by Paul Bourke - the filter is not explicitly shown.