Review: Digital Rapids TouchStream
For Flash streaming, for instance, the user is presented with three choices: Archive, Broadcast FMS, and Broadcast Push. These can be enabled (default) or disabled at will, so the TouchStream can be used strictly as a recorder or as a stand-alone Flash streaming "server," or it can be integrated into a Flash Media Server environment.
For the Archive setting, the touch interface allows for browsing a drive (the C: drive on the prototype and the D: or media drive on the v1.0 machine) and selecting a folder. A new folder, a file name, or a predefined sequence for the name (e.g., combinations of project name and encoding start time) can also be chosen or manually entered via the on-screen keyboard. However, Digital Rapids recommends that an external hard drive be attached for storing archive files; it provides two USB 2.0 and two FireWire ports on the back of the device to connect external hard drives, some of which can also be bus-powered (powered by the TouchStream itself rather than requiring an external power supply).
Enabling the correct choices on the Output screen is critical, as the default enabling of a streaming option without the appropriate server—or even a network connection, for which there is no warning during setup if the Ethernet is disconnected—may render a cryptic "critical error" at the time of encoding. The TouchStream would do well to provide some sort of early warning system for network or configuration errors similar to what is available on a few other encoding boxes.
Once the appropriate archive and stream choices have been made and the details have been entered for particular servers, the user can choose input settings: Here the choices are between 4:3 and 16:9, composite or s-video, and unbalanced or balanced audio. The test unit presented these in a series of choices, and a small video window in the upper right portion of the screen corresponded to the aspect ratio, showing what the content would look like on the larger encoding screen. Currently, the TouchStream does not have the ability to shift between the input view (video signals being received on the composite or s-video connectors) and a postencode view ("confidence monitoring" of the actual stream), but Digital Rapids says this is high on the list of changes to make.
Two other settings are available to the user—video settings and audio settings.
Video settings allow for basic picture control, a bit of noise reduction, and cropping of the video image. An additional video setting is the graphic overlay, which can be loaded into the machine and placed on the screen. While most studio locations already have a "bug" inserter to overlay a logo in the lower right corner of the video window, most field portable encoding units do not. This graphic overlay, which eliminates the need for another piece of field hardware, is a welcome addition on the TouchStream.
Audio settings are fairly rudimentary, with overall levels and bass/treble tweaking. A nine- or 12-band software equalizer would be a welcome addition for field projects where 60hz hum or HVAC rumble can often be an issue and would eliminate the need for another piece of field hardware.
Once these settings are selected, the trigger should also be set. A trigger is the "arming" of the start/stop button that will be presented on the main screen, the scheduling of a start time, or the scheduling of a duration of time to encode once the encoding begins. Settings on the trigger page will correspond to the availability of certain options on the main encoding page.
Choosing Done switches the interface back to the main screen, which presents the Start button along with buttons for the graphic overlay (Fade In, Fade Out) and the video and audio settings buttons for rapid tweaks during an encoding session. A final button, labeled Info, allows the user to see the encoder state and details on the IP address and streaming ports, as well as the hardware utilization monitoring noted above.
For those streaming technicians concerned about user mishaps such as accidentally choosing the wrong input or overriding an input setting, TouchStream provides a series of lock-out options. In v1.1 of the software, a technician can enter the security dialog area under Settings and choose to restrict or allow everything from triggers to input types, black levels, and even the start/stop button.
If start/stop is restricted, the unit will start encoding automatically on a reboot. This allows for a "persistent streaming" that Digital Rapids calls its "no click streaming" feature. In essence, after the power switch is pressed and the unit boots up, it immediately begins streaming at the predefined project settings. This is helpful for scheduled events or other instances where the unit might also need to be set to autolaunch when powered up. With the settings of Windows XP Embedded, the unit can also be set to restart immediately upon shutting down, providing a consistent "always on" streaming loop.
Should there be a need to disable autostreaming, the unit first needs to be unlocked through a security code via the on-screen keyboard, and then manual streaming should be re-enabled in the security settings.
As the unit is based on Windows XP, reboot times will range from 10 to 30 seconds. The unit also responded well to pulling the electrical connection midstream and then plugging it back in, one of the typical tests I perform; the Windows operating system often doesn’t handle this as well as a Linux or RTOS-based encoder, but the TouchStream worked after repeated power failure tests.
Digital Rapids recommends leaving the start/stop button visible, even if it is not active, for two reasons: The first is so that scheduled encoding can be verified, although the company has also added a small green Wi-Fi bar symbol in the bottom right corner that pulses to show a stream or local encode is occurring in v1.1. Second, and perhaps more importantly, if a graphic overlay has been chosen prior to restricting video settings, the Fade In and Fade Out buttons can still be operated, allowing for the insertion of a bug at select user-defined times during the stream, although the graphic can’t be changed.
Given this ability to lock out certain buttons and functions, it would be helpful to tie particular interface scenarios to projects. As of v1.1, though, there is only one level of security restriction, meaning that the lock-out settings will need to be changed each time.
After all of the setup and preparation, streaming is very straightforward. We tested manual and scheduled streams without incident. Using the duration setting on our test machine, we occasionally ran into an issue where the screen would freeze part way through an encode; letting the encoding time pass the duration we’d set, though, and forcing the machine to reboot showed us that it had actually been recording when we checked the archive files.
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