Jamie's Random Musings on Video IM
Having spent a good part of the last year struggling with a variety of video chat and IM programs, I have decided to write a few things down and see what other people have to say about them.
Tuesday 18 December 2007, 10:00 AM
Loose Ends - Gizmo, SightSpeed
Here are just a couple of comments and wrap-ups about previous topics.
The Gizmo Project - I sent a report to Customer Support about the audio device selection problem. I got a response less than 24 hours later, telling me that the problem was known, would be fixed in the next release, and was already fixed in the current Gizmo 4 (with video) release, if I would like to try that. This is what customer support is supposed to be like - prompt, and well informed. If you are still waiting FOUR DAYS for any kind of answer from technical support, you need to seriously consider changing to a real product. Otherwise, I have been using Gizmo rather extensively, and have been very pleased with the quality and reliability.
SightSpeed - I'm having more and more success in getting my contacts to convert from Skype to SightSpeed, and the comments I get after they change are always the same - "Wow, this is great!". I've talked with my brother a number of times, on his 128k connection, and it has been just fine. I've spoken with Grant several times, who has a faster connection, and it has been excellent.
I will be traveling for the next 10 days, so I'll be putting all of these to the test on the road.
jw 18/12/2007
Sunday 16 December 2007, 9:36 PM
The Gizmo Project
Next on my list for evaluation is The Gizmo Project. Gizmo actually comes in two (well, three) varieties - a text and audio only client (no video) for Windows, Mac and Linux; a text/audio/video client that is still in beta test, only for Windows, and a version for mobile devices that runs on various internet-enabled smart phones. At this time I am going to be looking at the text/audio client for Windows only. I will take a look at the video client in the near future.
You can download gizmo from the obvious location (www.gizmo.com); the file is medium-sized (12 Mb), and installation is quick and easy. Of course, with no webcam setup to worry about in this version, it is even a bit easier than the other programs I have looked at so far. Once the installation is complete, you will have the opportunity to either create a new Gizmo account, or log in an existing account. After you log in you will get the "Getting Started" window, the last of the options in that window is to make a test call, which is always a good idea with a new installation of an unfamiliar program.
If you have more than one audio input or output device, you will probably want to go to Edit / Options / Audio to select the devices that you want Gizmo to use. I ran into the only significant problem I have found so far with Gizmo at this point. If you select audio devices that are different from the "Windows Default" devices, as I do (I always put VoIP audio in/out on my headset, but Windows audio out on a Logitech Audio Hub speaker, and Windows audio input I don't pay much attention to, so it stays wherever it lands), then every time you start Gizmo you will find that it is using the Windows default devices - even though if you go to Edit / Options / Audio you will see that it knows perfectly well what you have selected, and if you hit "Save" in this window the device settings will take effect again. It's a strange bug, and a minor pain, but I have found that it is easy to just make it a habit when starting Gizmo to do this first thing, then you don't have to worry about it any more.
Once you get it set up and devices selected, making PC-to-PC calls is easy and call quality is very good. I have tested with my usual array of connection types and audio hardware, and I was consistently pleased and occasionally pleasantly surprised. The audio quality is quite good even on a 56k dial-up connection, and of course it is excellent on a broadband connection.
Once I had confirmed that everything was working with outgoing calls, I started trying incoming calls. Then the fun started... First, I found out the hard way that voicemail is activated by default after installation. My brother was trying to call me, and I saw no indication of an incoming call on my computer. He kept getting the standard voicemail prompt, until I finally figured out that voicemail is active by default after a new installation of Gizmo. Deactivating that stopped incoming calls from going to voicemail, but they still didn't come through to my computer, either, now my brother was getting a message saying that I was not available, please try again later.
I spent quite a lot of time searching for a solution to this problem. I found that I could receive incoming Gizmo calls when I was at my office, and even when I was at home but connected via dial-up instead of my usual Cable Internet Connection. So I assumed that there was something wrong with my cable internet router (a Linksys WRT54GX4). After a lot of searching, in both the Gizmo User Forum and Linksys User Forum, I found a very short note that said there was a "uPnP" setting in the router, and having it deactivated would stop incoming calls from getting through the router. I checked, and sure enough it was disabled on mine. I enabled it, and calls came through just fine after that.
Once I got these problems sorted out, Gizmo has worked just fine for me - and my brother actually prefers it. He has recently purchased an old laptop on eBay, which only has 802.11b wireless networking built in, so at that speed he is better off with audio only anyway. As I said above, the audio quality is good, and the program is nice and simple to use.
When you are in a Gizmo call, there is a "Map It" button in the active call window. Click on that and it opens a map showing the two ends of the call. Kind of a neat "gee whiz" kind of feature.
Overall, I have been very impressed with Gizmo, and I would recommend it to anyone who would be satisfied with a text and audio client, and no video. Just remember to watch out for the two big irritants:
- If you have multiple audio input/output devices, every time you start Gizmo you should go to Edit / Options / Audio and just click "Save", to be sure it has selected the devices you want.
- Voicemail is activated by default, so if you don't want it go to Edit / Voicemail Settings, and un-tick the "Activate Voicemail" box.
Also, if you have a Linksys router and you have trouble with incoming calls, go to the router Administration page and make sure uPnP is activated.
Of course, Gizmo is good for more than PC-to-PC calls and text chats. They also have CallOut and CallIn to/from PSTN (POTS) phones, and the ability to chat and even talk with friends on other SIP-based services, which can be very nice. I will go into more detail on these features in my next blog entry.
Friday 14 December 2007, 1:09 PM
Tech Talk - A Peek Behind the Curtain
I've spent a lot of time discussing video quality, resolution, frame rate, bandwidth and the like. But after using this information to set the video resolution, or optimize your setup to get the best possible performance, how are you going to know if it actually worked? Well, the obvious way is to look at the screen and see if it is "better". But being an engineer, that's far too objective for me. This blog entry will describe how to get SightSpeed and Skype to tell you about what is going on behind the curtains. I'll also explain what a few of the most important parts mean.
SightSpeed actually has two kinds of technical (aka debug) information available. One is about the general operating environment it finds - your computer, audio and video devices and internet connections - and the other is details about a call in progress. To get the general information, make sure the SightSpeed main window is "active" (focus), then press Ctrl-D. A new window will open with the general technical information. Some of that information you will probably be able to understand pretty easily - for example your CPU type and speed, amount of memory installed and available, and operating system version. It will also tell you about whatever speaker, microphone and cameras it finds, with a lot of technical information about various capabilities of each. If you are trying to use a "non-typical" webcam, such as one connected by FireWire or a video capture card, you can see here if SightSpeed detects the camera at all, and if so what capabilities it thinks the camera has.
To get the technical info for a call, once you have the call connected make sure that you have the "full window view" (the one with the incoming video and your contact list, not the "video only view"), and then press Ctrl-S. A new window will open, and you will see the current, peak and average data rate, the video resolution and frame rate, CPU load and connection latency. If you watch this technical data for a while during a call you will see that SightSpeed does quite a good job of getting the video frame rate up to 30 FPS quickly at the beginning of a call, and then varies it as necessary to compensate for environmental changes, but always returns to 30 or so relatively quickly. You will also be able to see if either your own video or the incoming video is being limited to something less than 320x240 resolution, which can happen because of camera, CPU or bandwidth limitations. When I was testing with my brother on the 128k internet connection, for example, his video was only 128x96 resolution. That's still acceptable in the standard video window, but don't try to stretch that window too far - and stay away from the "Full Screen Video" button! If you have an older/slower computer, keep an eye on the CPU load shown in this window. If it is consistently above 90%, your computer really isn't up to the task and your call quality is likely to degrade. This is often caused by overly demanding cameras; the latest Logitech cameras and drivers call for a minimum 1.4 GHz CPU with XP and 2.4 GHz with Vista and that is taking a big bite, and might not be leaving much processing power for the video call itself! If you find yourself in this situation, take another look at my previous blog entry about not buying the greatest, fanciest (most expensive, most demanding) webcam on the market just for video chatting. My friend Grant and I were testing cameras yesterday evening, and found that the video quality from a very simple and inexpensive Philips SPC505 camera was not much below that of the SPC900, and the load it puts on my system is considerably less!
Skype has a single large "technical call info" window. To get it, you must first activate the option, by going to Skype / Tools / Options / Advanced / Connection, and tick the "Display technical call info during calls" option, then "Save". Then, when you are in a call, put the mouse cursor in the Skype main window and after a few seconds a new window will come up with the Skype call technical info. (Like most everything else in Skype, this "doesn't always work" - sometimes it just doesn't show up.) There's a LOT of information there - it kind of reminds me of their "Options" windows, it looks like everything they ever needed for any problem is still in there, some things several times! Some of the most interesting parts are "Relays", which tells you if you have a direct P2P connection (when it is zero), or if your connection is going through some other computers along the way. Having any relays is not good for performance and quality, and having four or more is very bad. Related to that is "SessionOut" and "SessionIn", if they say "RELAY_" something, then you really are not getting a good connection, perhaps because of firewall or NAT router problems, video call quality is likely to be very low, and file transfer is likely to be better by post than over that link. If you are making a video call, the "Video Send" and "Video Recv" lines will tell you about the current video quality and give you some hints about why it might be limited. Obviously, FPS at the beginning of the line is the frame rate, and 320x240 (or whatever) near the end is the resolution. Within the parenthesis you can see what Skype estimates the maximum frame rate at the current resolution for various components is: "cam" is the camera itself, "bw" is the connection bandwidth, and "cpu" is the processing power of your computer. If the effective frame rate is less than 30 FPS, you might be able to tell from these where the bottleneck is, and thus what you need to improve. Again, if you watch this technical info during a call, you'll see that Skype drops the frame rate about as quickly as SightSpeed when there is some external disturbance, but it recovers much more slowly. Finally, at the bottom of the technical info window, if there is something that is being overtaxed or running low, you'll see an error indication, such as "CPU_LOW" or "BW_CRITICAL".
I haven't been able to find any similar "debug info" source for ooVoo. I suggested on their forums that it would be a nice feature, and they seemed receptive to that suggestion, so perhaps it will show up in a future release.
jw 14/12/2007
Thursday 13 December 2007, 9:52 PM
Tech Talk - Special Edition - Skype Video Resolution
Skype released a new "hotfix" version yesterday (12 Dec 2007), which restores the ability to specify the video resolution and frame rate by editing their config.xml file. The purpose of this special blog entry is to provide instructions on exactly how to do that editing. As usual, however, I have several things to say before I actually get down to the instructions.
Almost all of the discussion about editing the Skype config.xml file has concentrated on increasing the video resolution and/or frame rate for cameras other than the "chosen three" Logitech High Quality Video models, so that owners of other cameras that are just as good (or better) can benefit from improved video quality. However, this can also be used to reduce the video resolution or limit the frame rate. There are a number of situations where this can be very useful. One common one is if you have a volume-based price on your internet connection, and you want to use video calls but limit the amount of data they transmit. Another is when a company doesn't want Skype users to flood its network with video call data. The new High Quality Video mode is likely to make this even more important - if your camera, computer and bandwidth are good enough, you are going to get High Quality Video, and produce as much as four times more video data, whether you want it or not. By editing the config.xml file and setting the video resolution to 320x240 (or less), you should be able to stop High Quality Video mode from kicking in. Note that I say "should", because I haven't been able to verify this yet, I do not have either a camera or a computer which are "blessed" by Skype. If anyone else tries this and verifies that it disables High Quality mode, I would appreciate hearing about it.
As with any changes that involve editing configuration files, you need to be very careful when doing this. The consequences of making any kind of small mistake are rather drastic. When Skype starts up, if it finds an error in the config file it will simply toss the entire file, and revert to the original default configuration. This is not a serious as it may sound, because it only means that you will lose things like your changes to the default "View", "Tabs and Panels", Skype main window background and the like. You will not lose your contacts, chat history or any such things. Indeed, it sometimes seems like the "recommended solution" to half the problems reported in the Skype User Forums is to delete the config.xml file, or even the entire Skype Application Data directory, and let Skype recreate it the next time you start it. Still, if you want to be safe rather than sorry, the smart thing to do is to make a copy of the config.xml file before you start, either under another name, or in another folder or on the desktop. Then if you start Skype and find that something went wrong, and it's all gone back to the original configuration, you can just shut down Skype again and copy that backup into the Skype directory again.
Ok,with those preliminaries out of the way, here are the instructions:
- Make sure Skype is not running before you start this procedure. Skype updates its config.xml file periodically, so if you make these changes while Skype is running, you are likely to lose them and have to do it all over again.
- Open an Explorer window on the Skype Application Data folder. One simple say to do this is by going to "Start" (the "Orb" on Vista), then "Run...", and then type %AppData%\Skype in the "Open:" field. You can accomplish the same thing by typing %AppData%\Skype in the address bar of any Explorer window, such as you would get by double-clicking "My Computer" or "My Documents".
- In the Skype folder you will see a sub-folder with the same name as your Skype login name; double-click that to open it.
- In this folder you should see a file named "config.xml", or just "config" with a description that says "XML Document". Make a copy of this file now, for example with right-click copy and paste, or with ctrl-drag-and-drop.
- Right click on config.xml (the original, not the copy) and choose "Edit". This should open the file in Notepad.
- Scroll down until you find the section that is bounded by lines of and . The editing you are going to do must be between these two boundaries.
- Add these two lines within the "Video" block:
<CaptureHeight>480</CaptureHeight>
<CaptureWidth>640</CaptureWidth>
Indentation and placement within the block don't matter, Skype will rearrange this as it wants the next time it reads and then rewrites the file.
- Save the changes and close Notepad.
- As I said, you need to be very careful with these changes, because if you make even a small mistake, Skype will throw away the entire file. I have gotten into the habit of testing my changes before starting Skype by simply double-clicking on the config.xml file in the explorer window again after I close it. By double-clicking (or right-click and choose "Open"), you will open the file in Internet Explorer, which will parse the XML content of the file and will tell you if there are any problems with it.
- Start Skype. If you have made a mistake in editing the config file, you will see that any changes you have made to the Skype main window are gone, and it may even bring up the "Create a New Skype Account" window. Don't panic, just shut down Skype, copy the backup you made to the Skype login directory, and try the editing again - and be even more careful this time.
If you look at the Skype User Forums, you well see that some of the "experts" there say that you should add a 30 line to the config.xml file as well. This is absolutely not necessary, the default maximum frame rate in Skype has been 30 for quite some time now - at least since the first 3.5 release. You only need to add an Fps line if you want to limit the maximum frame rate to less than 30 FPS. Skype seems to give priority to frame rate over resolution, and it is determined to get to 30 FPS by default, so if your computer isn't quite up to that speed, you can watch the technical data from Skype and see it running the frame rate slowly up until it overloads either the CPU or bandwidth, then it will drop way down, and start to slowly rise again. In some cases it will finally get disgusted with this game and reduce the resolution to the next lower step, then start the frame rate game all over again. In such cases you may decide that a frame rate of 20 FPS, or even 15, is "good enough" for what you want, and in order to eliminate the constant adjustment and preserve the higher resolution, you can add a line to the config.xml file saying <Fps>20</Fps> or 15, 25, whatever you like. The only thing you can't do is set it above 30 or much below 10. (I think the lower limit is about 7 or 8, but honestly the video quality at that frame rate is so bad that I've never had the patience to watch it long enough to figure it out.)
Making these changes to the config.xml file does not guarantee that the resolution and frame rate will stay at the values you specify; in fact, it doesn't even guarantee that Skype will start at these values, it only serves as an advisory startup value and a maximum limit value. When you start Skype it will try to bring up the camera at the resolution you have specified, but if it is unable to do so for any reason, it will simply drop down to lower and lower resolutions until it succeeds in starting. If your camera has an "active" led, you can actually see each of these attempts to start up, the led will light up briefly and then go out again. At one point in my testing I had 640x480 in the config.xml file, but I was connecting to an older laptop that couldn't receive video at that resolution; the camera activity led went on and off six times before the video actually came up, at 320x240 resolution. As for frame rate, Skype will always start at 15 FPS and then (slowly) adjust either up (if possible) or down (if necessary). As I have said, the maximum frame rate in Skype is 30 FPS, so if the conditions allow it Skype will eventually get there and just remain stable. At the other extreme, if it can't keep the frame rate above about 10 FPS, it will eventually drop the resolution to the next lowest step, and then start the frame rate at 15 again.
Thursday 13 December 2007, 10:09 AM
Tech Talk - Video IM Tips and Tricks
As usual with my "Tech Talk", this will be a somewhat more technically detailed description of some things to do, to avoid, or to simply keep in mind to avoid problems or to find them when they arise. This one is going to concentrate on hardware, and the next will be about software.
First, cameras. The vast majority of Video IM users have USB-connected webcams. Always remember that these cameras should be connected directly to the computer, not through a USB hub. Some camera manufacturers are very clear about this - Logitech, for example, goes so far as to say don't even use a USB extension cable - while others don't say anything at all. But my experience has been very clear, cameras connected to USB hubs are very frequently a problem, so it is best avoided.
Also give some consideration to the number and type of USB devices you have connected. A USB connection is just what the name says - a BUS, and as such it has some maximum amount of data transmission capacity. Try to avoid having other high data rate peripherals connected via USB. The most common example of this that causes problems is having your internet connection via a USB, either a WiFi adapter or cable modem, for example.
There are other less extreme examples of USB loading that you can avoid, as well. I have seen situations on my older laptop where I could improve video call quality by changing from a USB microphone and USB speakers, or a USB headset, to a headset plugged directly into the laptop mic/speaker audio jacks. Actually, while I am on the subject of headsets, I got lucky with one of the first that I bought, it has worked out extremely well for me. It is a Logitech Premium Notebook Headset, and it comes with an adapter so that I can connect it either via mic/speaker jacks or USB.
Try to avoid other high-volume internet activities when you are in a video call. While I was testing SightSpeed with my brothers last weekend, I was admiring how good the video quality was when my partner sent an email with several large pictures attached. My video call went straight out the window - first the picture froze, blocked and jumped and the audio went choppy, and then when SightSpeed noticed the dramatically lower bandwidth available it reduced the video resolution from 320x240 to 128x96! Of course, this was a rather extreme case, because not only are we sharing the internet connection, but at that time we were both running wireless connections from the same router.
That brings me to the last topic for today, the internet connection. As I have said, for these Video IM programs, it needs to be a broadband connection, but that still leaves some "wriggle room" over what qualifies as "broadband". Wikipedia says that a broadband connection should be a minimum of 256kB download speed, but then avoids the issue of upload speed altogether, saying only that some connections, such as ADSL, have different (slower) upload than download speeds. Well, DUH! That's the "A" in "ADSL" - "Asynchronous", meaning that the speed is different in each direction. For our purposes, the upload speed is likely to be just as important as the download speed, because we are trying to send video as well as receive it. That is why you have to be careful about low cost (implying low speed) connections such as my brother has in Atlanta; the 512k download speed qualifies it as "broadband", but the 128k upload speed can be a problem for Video IM programs.
The three programs I have looked at so far in this blog have different requirements and recommendations, and different degrees of success or failure at low speeds. SightSpeed actually does pretty well on a 128k upload connection. As I said, the video and audio with my brother were certainly acceptable. We did notice that it would get overloaded occasionally, especially if he started moving around or waving his arms (which increases the volume of video data), but by and large it was more than acceptable. From what I have heard from both the CEO and CTO of SightSpeed, they seem to be quite proud of the fact that it works pretty well at only 128k, and justifiably so in my opinion. The ooVoo web page only says that they require a "Broadband Connection", but I have been told by their Director of Marketing that they expect to have a minimum upload speed of 256kB, and my tests confirm that. Skype says on their web page that they recommend a minimum of 384 kB for either normal or high quality video. I was, as usual, unable to get Skype working properly in my tests with my brother - we had all sorts of problems with freezing video, dropped connections and the like, but I don't know whether this was because of his relatively slow ADSL connection, or if it was just typical Skype unpredictability. I considered trying to contact Skype Support for advice or information, but I don't have FOUR DAYS to wait for even the first totally inane reply, so I just gave up on it.
If you have a wireless (WiFi) connection on your computer, there are a couple more things to be careful about. If you have an older laptop, wireless adapter or router, they might still be using the older "B" wireless standard, which is considered quite slow today. It might be worthwhile to upgrade to "G" or "N". Start by checking each component of your wireless equipment. You might find that you already have a Wireless-G router, but only a Wireless-B adapter in your computer. In that case, for the relatively small cost of a new wireless adapter, you can dramatically increase your connection speed. If you decide to upgrade all of your equipment, I would recommend that you go to Wireless-N now, and stay away from the vendor-proprietary "Speed Enhanced" or "Range Enhanced" equipment. Not only do you lock yourself into one vendor if you use that, you also leave yourself open to being "orphaned", as I was, if the vendor decides not to continue development, make Vista drivers, or whatever.
Finally, if you are using a wireless internet connection and you seem to have interruptions, distortion or even dropped connections every minute or so, you might be running into problems with the Windows XP "Wireless Zero Configuration Utility". Basically what this service does is periodically look around for a "better" wireless connection than the one you currently have. That search and evaluation can interfere with smooth wireless operation. If you are sitting still and connected to your own router, you probably don't want or need for it to continuously look for something better, so you could go to the Windows Services control, find "Wireless Zero Configuration" (near the bottom), and Stop it.
jw 13/12/2007
Previous
