Free intermediaries software for linux

Python Traffic Analyzer is a Python base class and sample driver script written to retrieve and manipulate images from the TrafficLand cameras and calculate a numeric value representing the current traffic flow.

PyTrAn, an example driver script, an image collector and an image mask creator are available for download from the link shown at the bottom. To use the PyTrAn package begin by choosing a camera that you wish to analyze, for this example well use the camera captioned above.

We want to construct a mask over the area of the image that we are interested in, namely the road. In this particular example the road takes up the majority of the image but that is not always the case.

We will apply the mask over captured images to fine tune the area over which we are looking for movement. To create the mask we will first need to collect a sequential series of snapshots from the target camera. The image_collector.py script was written for this task:

$ mkdir mask_200003
$ cd mask_200003
$ ../image_collector.py 200003 30
Collecting 30 images...
30

Done.

The script is hard coded to capture images on a 2-second delay. The delay is necessary to ensure the image has changed. I believe 2-seconds to be the absolute minimum. Once complete, 30 images numbered 1 through 30 will be created in the current directory.

We construct a mask from these captured images by creating a diff-image for each sequential image pair and then adding each diff-image together. Naturally, a script was written to automate this task as well:

$ ../mask_maker.py 1 30
Creating a diff for each sequential image pair.
Diffing 29

Creating the initial mask from the first image pair.

Adding the rest of the diffs to the mask.
Masking 29

Done.

A number of .diff files are generated in this process. These files repesent the movement between individual sequence pairs.

The .diff files are simply intermediary files, the important bit is the mask file, which is generated as the sum of all differences.

The mask file may be dirty (as in this case) and require manual cleanup. The basic shape of the road however is clearly visible, evidence that we can with minimal effort automate the mask generation process. Also, this run was conducted at night, day-time images yield better results.

There are a few final steps we need to take before we can use the example PyTrAn driver script. First we need to convert the mask to ASCII (noraw) format:

$ pnmnoraw mask > mask_200003.ascii

Then we need to open an ImageMagick display window and get its X-window-ID using xwininfo. Finally, update camera_id and window_id in pytran_sampling.py and launch the driver:

$ ../pytran_sampling.py
DEBUG> grabbing frame from camera 200003
DEBUG> rotating image: pytran.this > pytran.last
DEBUG> refreshing image in 3 secs
taking a 5 minute sample at various thresholds.
DEBUG> grabbing frame from camera 200003
DEBUG> generating frame diff on pytran.last, pytran.this
DEBUG> displaying image: pytran.diff
DEBUG> converting pytran.diff to ascii
DEBUG> calculating traffic ratio...
ratio[5]: 55%
DEBUG> calculating traffic ratio...
ratio[10]: 52%
...
...
5 minute sample[5]: 67.88
5 minute sample[10]: 42.66
5 minute sample[15]: 30.57
5 minute sample[20]: 23.03
5 minute sample[25]: 18.39
5 minute sample[30]: 14.79
5 minute sample[35]: 12.42
5 minute sample[40]: 10.53
5 minute sample[45]: 9.06
5 minute sample[50]: 7.85

The sampling script will take 5 minute samples at varying color thresholds. The optimal threshold must be manually chosen. Furthermore, you will need to sample the traffic ratios during both heavy and light traffic times to get a good feel for your acceptable range. Also, keep in mind that the traffic ratio value is simply the percent change detected, or in other words the movement detected within the masked region. This means that a completely empty road will register similar values to a road so congested it looks like a parking lot. The time of day can be combined with the traffic ration to determine the logical truth.

With this task implemented and abstracted more complex systems can be built. When I find the time Id like to create a system that will take multiple potential travel routes and times, and during the travel time e-mail the traveler with the best route to take. Another idea I had would be to record the traffic flow values for each camera, for each day and for each half hour interval. Travelers and other interested parties can then analyze traffic patterns to determine the fastest route dependant on date/time.

Orion Secure Message Gateway (OrionSMG) is a secure message gateway for transporting ebXML, SOAP, and custom message formats. It complies with the OASIS ebXML 2.0 specification, and can act in both intermediary and processing MHS roles to provide end-to-end reliable messaging.
Orion Secure Message Gateway software runs natively on Linux, OS X, and Windows with ODBC/PostgreSQL database support.
Enhancements:
- OrionSvnInfo.h now in correct directory.
- Old documentation temporarily added.
- Minimal README.txt file added.

Kvblade project is a kernel module implementing the target side of the AoE protocol. Users can command the module through sysfs to export block devices on specified network interfaces.

The loopback device should be used as an intermediary for exporting regular files with kvblade.

The individual binaries are:

• pak - create a stream from regular files, based on a portion ("segment") list
• upak - completely write out regular file segments from a stream
• pakmerge - merge multiple streams in regular files into a single stream
• paksplit - split a stream into regular stream files of fixed size
• mklist - create a segment list
• The name "stream" is somewhat unfortunately chosen. It doesn't have to do anything with STREAMS or with stdio streams. It denotes a very simple file format.

Major Features:

1. Transfer multiple, possibly very big, regular files between possibly different hosts you have shell access to without transmitting any file names.
2. Supports on-the-fly Blowfish-CBC encryption
3. Easy and portable to handle, transfer and format/scan file offsets of any magnitude. This is achieved with a handful of very naive and simple "bignum" functions.
4. Portability and fun (as opposed to efficiency) were the primary aspects of development.
   

Enhancements:

• The programs "pak" and "pakmerge" were modified to flush stdout before printing "segment done" messages to stderr ("Paksplit" and "upak" already did this for output files.) This way, whenever the user sees a "segment done" message, he/she can be sure that even the last chunk of the segment was passed to the kernel via write().

Songs is a graphical tool to record and mix audio files. It supports an infinite number of tracks, huge audio files, and various effects.
One important motivation for Songs was the need of a recording tool under Linux. There are some already existing (see the links below), but these are too complex, too huge, eat too much memory and resources. Small machines can be used to record and mix audio files, even with a graphical interface. Songs is trying to prove it.
The recording is done directly to disk, so that with small machines, whithout much memory you can still record.
There is a full duplex mode, but full duplex is not very well handled with OSS. You dont really know if your two streams of samples are synchronized or not, and the interface provided by OSS does not help much with that. So, currently, take the full duplex mode as is. You probably will need to move by hand audio tracks to let them be synchronized.
Main features:
- Unlimited number of tracks.
- Supports WAV files (mono, stereo). Only 44.1 KHz, 16 bits files are supported, because Songs was born mainly to help me create music I could store on audio digital compact disks.
- Supports raw float files (mono, stereo). Very useful when you are mixing and that you eat too much resources. Simply put in a new file your current mix, and use this new file instead of several ones. Using float numbers gives more precision of the intermediary mixing.
- Several effects (currently not that much, but it is planned).
- Not too much memory used. All the audio files are mapped directly into the memory, so that the Linux kernel can swap them very easily. It means that if your files can exist on your disk, any size they are, they can be used with Songs (with a soft limitation of virtual memory space, which depends on your setup, and a hard limitation of 2 GB, because of the use of signed integers, which currently are 32 bits numbers).
- Use of gtk 2.0, for the good and the bad. The good is that the interface was done quickly. The bad is that the gtk documentation is far from perfect, that gtk is not bug free, that I may use it the wrong way sometimes and that it may change in the future, forcing Songs to be changed (and what if the Songs authors dont feel the need to do so, for example by lack of time?).
Enhancements:
- sc1.c sc1_gui.c:
- New files, ripping a compressor from sc1_1425 coming from swh-plugins-0.4.11.tar.gz (see http://plugin.org.uk/).The compressor was buggy, sometimes in rms_env_process
- r->sum was negative, leading to NaN for the sqrt stuff.
- pan/vol/pos.c: Checking return value of malloc (no, it was not done, shame !).
- various files: Fixing a realloc misusing (doing realloc(size+=32) then size+=32, which finally means size+=64 but only allocing size+32 stuff, weirdy to find).
- help_gui.c: The "About" stuff only appeared once, fixing it.
- various files: Fixing bugs those last days, forgot to feed this Changelog.

Socketpipe project connects over a TCP/IP socket a remote command specified to a local input generation command and/or a local output processing command.
The input and output of the remote command are appropriately redirected so that the remote commands input will come from the local input generation command and the remote commands output will be sent to the local output processing command.
The remote command is executed on the machine accessed through the login command. The socketpipe executable should be available through the execution path in the remote machine.
The braces used for delimiting the commands and their arguments should be space-separated and can be nested. This feature allows you to setup complex and efficient topologies of distributed communicating processes.
Although the initial socketpipe communication setup is performed through client-server intermediaries such as ssh(1) or rsh(1), the communication channel that socketpipe establishes is a direct socket connection between the local and the remote commands.
Without the use of socketpipe, when piping remote data through ssh(1) or rsh(1), each data block is read at the local end by the respective client, is sent to the remote daemon and written out again to the remote process.
The use of socketpipe removes the inefficiency of the multiple data copies and context switches and can in some cases provide dramatic throughput improvements. On the other hand, the confidentiality and integrity of the data passing through socketpipes data channel is not protected; socketpipe should therefore be used only within a confined LAN environment.
(The authentication process uses the protocol of the underlying login program and is no more or less vulnerable than using the program in isolation; ssh(1) remains secure, rsh(1) continues to be insecure.)
Enhancements:
- This version corrects a bug in the command parsing of the Windows version of socketpipe.