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This is probably the most difficult part
of using SVCR for a new user because the
link or URL to many streams is not always
easy to find. However there are a number
of techniques you can use. Before attempting
to find the URL always check that the actual
stream works by clicking the link or icon
on the web page that references the stream.
If the stream will not play then SVCR will
not capture it.
In most cases more than one of the techniques
described here will work - in those case
use the technique you find personnaly preferable.
After awhile you will probably settle on
one or two methods that give you good success.
If one method does not work, move on and
try another.
Pasting The Web Page Link
Sometimes it is as easy as right clicking
the web page link or icon for the stream
and selecting Copy Shortcut and pasting it
into SVCR.
Redirector or Metafiles
A redirector or metafile is generally a temporary
internet file (found in C:\WINDOWS\Temporary
Internet Files\ . . . ) of the type .ram,
.smi or .smil for realmedia streams and .asx
for windows media streams. You can find these
files by starting the stream and then using
Windows Find Files to search for files of
the type *.ram (or *.smi, *.asx). You may
want to restrict the scope of the search
to files with todays date. If you find such
a file, open it in a text editor and you
will likely see a simple text file that will
contain links or URLs like pnm://abc.def/ghi.ra,
rtsp://klm.nop/qrs.rm, mms://tuv/xyz.asf,
http://zyx.vut/srq.asf or the like. In all
likelihood these are the link(s) to the stream(s).
Paste it in SVCR and see if it works. You
could also paste it into realplayer or windows
media player to double check that the stream
plays. You may also be able to get these
redirector files more directly by right clicking
the web page link or icon and selecting Save
Target As. This would download the metafile
which you could then open using a text editor
to find the URL.
In same cases you may find a .smi link like rtsp://abc.def/ghy.smi in the .ram file. This URL may or may not work when you paste it into SVCR. If it does not work, see SMIL Files below.
Embedded (Javascript) Players
Many web pages will use realmedia or windows
streaming media but when you click on the
web page link or icon for the stream an embedded
player will open and play the stream. These
embedded players are generally written in
javascript. You may see some similarities
between this embedded player and realplayer
or windows media player, or it may look very
different. A lot of these web pages will
use metafiles or redirector files. So the
strategy would be to start the stream playing
and then search for the .ram or .asx file
and look for the link as described above.
Some javascript players will store the stream
link in a .htm or .html file. You can generalize
the search for redirector files by using
Windows Find Files to search for all files,
*.*, that were modified on todays date (otherwise
the list could be very long), that contain
the text mms or .asf or rtsp or .rm, depending
on the type of stream. This will find any
file that was modified during the current
day that contains text that is indicative
of a stream URL. Open these files in a text
editor to search for your link. Beware of
any files in the C:\WINDOWS\System directory.
Don't open these as the link will not be
there. The files you want will be in a temporary
internet file directory.
I have observed for some embedded window
media players, the URL will change everytime
you start the player playing. The URL will
look normal but there will be a long string
of letters and/or numbers that is part of
the URL, for example,:
mms:// blahblah:7?auth=Vild.dJc6aGb3cUdmc7ddGzVco-7yCG6-bWG-IDpEmsE1
mms://blahblah/asp?Station=987&Provider=47894567
The red-colored strings change everytime
you run the stream. It must be included as
part of the URL though. Each of these "time
stamped" URLs remains valid for only
a period of time. So, next time you want
to run SVCR you may have to repeat the process
of actually playing the stream and searching
for the new URL. This is where a macro/scheduler
software tool is useful for automating such
tasks.
Sometimes you will end up with a URL that
ends in .smi. This may or may not work in
SVCR. If it does not, see SMIL Files.
And you may be unsuccessful at finding any
redirector file or any URL. In these cases
see Packet Sniffing.
SVCR Links Capability
You can use the built in capability of SVCR
to find all streaming links on a web page.
First select the Links tab, right click within
the tabbed window and select options. You
should see this window:
Here the Use filter box is checked and the Get all except radio button is selected. When SVCR "scans"
the web page it will will ignore all links
on the page that end in .htm. I could have
done the "inverse" and selected
Get only and specified links that would be streamimg
links, i.e. those that might end in .ram,
.asf, .asx etc. Select OK. Now paste the
URL of the web page into SVCR. SVCR will
now download an html file that is the web
page and scan it for links using the filter
properties you defined above. You should
see these links appear in the Links tab window. If you see one that looks like
a streaming link, double click it and SVCR
will attempt to download it.
If you click the the Source tab you will see the html source code of
the web page you have just downloaded. Also,
the HTML tab will display the webpage (as you would
see it in a browser) in its window.
Unfortunately, the Links capability of SVCR
is not always successful in discovering all
the streaming links on a web page. But it
is worthwhile checking if you are having
trouble finding a link.
SVCR Intercept Capability
The SVCR Intercept capability applies only
to Beta 3.1. This feature can intercept links
as you begin to play them with realplayer
or windows media player. You must have the
program intercept.exe in the same directory
as vcr.exe. (You should see the yellow icon
:
) Intercept.exe is normally distributed
with SVCR Beta 3.1. To enable the intercept
feature click the Capture tab in the right pane of SVCR. Right click within
this tab and select Options. You should see
:

Make sure you check the Enable MIME Intercept box and click OK. With the SVCR open, click the link or icon on the web page where the stream is found. This will launch the player and start the stream playing. If the intercept feature was successful at finding the link it will be displayed in the Capture tab window. Double clicking it will launch the SVCR download.
SMIL Files
SMIL is Synchronized Multimedia Integration Language pronounced "smile". The
SMIL "language" looks a lot like
HTML. Sometimes the reference to a stream
will be rtsp://blahblah/xyz.smi, which is
a reference to a SMIL file. In certain cases
SVCR will download the SMIL file, in other
cases it will not. Don't know why. Sometimes
reference to the SMIL file will be found
in a redirector or metafile file. The URL
of the stream, or enough information to reconstruct
the URL, may be found inside the SMIL file
(generally a small text file). So the goal
is to find the contents of the SMIL file.
If SVCR downloads it, open it up with a text
editor to view the contents. If not you will
probably have to use a packet sniffer to view the contents. In any event, lets
assume you can view the contents.
The SMIL file can look something like this
:
<smil> <head> <layout> . . . <layout> </head> <body> <video src = "rtsp://blahblah.abc/def.rm" begin = "00:20" dur = "3:00" /> </body> </smil> |
In this example the URL of the stream is
rtsp://blahblah.abc/def.rm and is found inside
the video source tag. Other tags to look
for in the SMIL file for URLs are <audio src = "URL" />, <ref src = "URL" /> and <animation src = "URL" />
If the tag looks something like <audio src = "soundx.rm" /> then the full
URL needs to be reconstructed. If, in this
case, the URL for the SMIL file was rtsp://server.name/sonic.smi,
then substitute soundx.rm for sonic.smi,
i.e. construct the URL : rtsp://server.name/soundx.rm.
In most cases this will be the correct URL.
There is an exception, however, when you
see the tag that sets each URL relative to
a base target or content (see the <meta name .... /> tag).
<smil> <head> <meta name = "base" content = "rtsp://myserver.company/" /> <layout> . . . <layout> </head> <body> <audio src = "mediafile.rm" /> </body> </smil> |
The URL in this instance is constructed by
taking the base-content value and appending
the audio source value, i.e. rtsp://myserver.company/mediafile.rm.
Packet Sniffing
When all of the previous methods fail you
can always resort to packet sniffing. A packet
sniffer is a program that can capture and
store Internet Protocol (IP) packets as they
arrive at you PC or are sent from your PC.
There are a number of these available, for
example CommView available from TamoSoft.com.
URL Snooper is a packet sniffer designed
to sniff or capture streaming media URLs.
It is probably the most useful and more importantly,
it is free. .You can get it here.