Create a Live Encoding session

Once you have decided on a streaming mode and established your video sources, you can begin your Live Encoding session. If you have not done either of those two steps, you should first see About streaming modes before getting started with this task.

To create a Live Encoding session, you will generally have to do the following. Scroll down through this topic to follow the workflow tasks sequentially.

  1. Enter the Live Encoding mode. The Live Encoding mode presents a different workspace than the standard Microsoft Expression Encoder workspace. You have to enter the Live Encoding workspace before you can build and broadcast your content.

  2. Set up the live-based and file-based sources that you will have to compose your broadcast. To capture a live video feed, you must connect a camera to your workstation and configure it so that you can view an image. To stream pre-recorded audio or video files, use the controls in Expression Encoder to specify the files you want to open, to arrange them in the order in which you want them to play, and to specify what actions you want them to take after they have played.

  3. Add a preset. A preset is a combination of encoding options and playback options that you can quickly apply to your content after you import it. Presets are especially useful if you need guidance about the best encoding scenario for your audience.

  4. Set up the encoding options. If you choose not to use a preset, or if you want to customize your preset or set your own encoding options, you can do so in the Encoding panel. You can also choose to intersperse your live broadcasts with captions.

  5. Add metadata to your streamed file. Add any information that may aid a viewer in searching for your file or classifying it.

  6. Add captions to your streamed file. Use the Script Commands panel to add text that will display, on your command, at any time during the broadcast. If you choose to archive your file, these captions become part of the archived stream. If you open your file in Expression Encoder, you will see the captions listed as script commands and displayed as markers. You can then modify the command text, realign the commands on the Timeline, and add new commands.

  7. Set the output options. In the Output panel, you set the streaming mode. You can either pull your content from Expression Encoder and send it to an available local port, or push your content to a Windows Media server. Then, if you want to save the encoded file for future on-demand delivery, possibly as a Microsoft Silverlight package, specify the appropriate archive options.

  8. Begin your Live Encoding presentation. Start your camera or open your files to begin encoding and subsequently recording and broadcasting your presentation in real time. As you broadcast, you can switch sources and insert captions into the stream on the fly.

  9. Archive and modify your presentation. Depending on the output options that you set, after you finish your broadcast, Expression Encoder saves an encoded version in the location you specify. You have several options for working with the file from that point. For example, you can create several streaming broadcasts in a single session while you are in Live Encoding mode and specify each subsequent file to open as a job so that when you exit Live Encoding mode, you can then package those files in Silverlight templates to prepare the files for an on-demand, rich web presentation.

To enter the Live Encoding mode

  • On the View menu, click Live Encoding Mode. When you first enter this mode, the Output panel displays the necessary set of tasks you must perform to initiate streaming. The tasks display as links, and when you click a task, the area of the user interface that corresponds to the task will illuminate. The links are helpful in orienting you to the workspace and tasks, and to quickly prepare your broadcast after you are familiar with the Live Encoding functionality. However, at first, you should refer to the following tasks to understand your options.

To set live video sources

  1. Connect your camera device, such as a USB Webcam, or a Firewire (IEEE 1394) digital video camera. Although you can connect multiple live sources, you can stream only one at a time.

  2. In the Settings panel, click the Live Sources tab.

  3. Live Source 1 appears selected by default if this is the first time that you are starting the Live Encoding mode.

  4. In the Device Configuration section, set the following options:

    • In the Video Device list, click the video device you want to use. Do the same in the Audio Device list. Once you choose your video device, the live image from that source appears in a window in the sources area.

    • Click the Configure button under the video or audio device list to set options that may be particular to the chosen device.

    • On the Resize Mode menu, choose how you want to display video whose source dimensions do not match the output dimensions. Choose Letterbox to maintain the aspect ratio and add black bars to the sides of the video, as appropriate. Choose Stretch to force the video to fit the output frame size.

  5. To add another live source, click Add. Repeat step 4 to configure the device. In the sources area, Expression Encoder displays the image captured by each subsequent live source that you configure.

  6. To edit configuration information for a device, click the appropriate Live Source button and repeat step 4. To remove a source, select it in the list and click Remove.


    You can remove any source from the list except Live Source 1.

To set file-based sources

  1. In the Settings panel, click the File Sources tab.

  2. Click Add,and navigate to the file that you want to use. You can open any file that Expression Encoder can import.

    For more information about acceptable file formats, see Supported file formats.

  3. Under File Source Settings, set the following options:

    • Name   Specify a name for the file source.

    • File   Displays the path of the file source. Click Browse for file sourceCc294579.b2c2da7c-7d8d-4578-ae1f-4ee611d2a274(en-us,Expression.30).png to change the file source.

    • Play then   Select an action to occur when your file reaches the end of its duration. Select Hold if you want the source to freeze at the final frame. Select Jump To to begin playing another source, and then select the source to play in the following list. You can choose only file sources that you have already imported. Select Loop to have the source perform a looping playback or, if your source is a still image, to display continuously.

    • **Resize Mode   **Select how you want Expression Encoder to resize images whose original dimensions differ from the output dimensions. Choose Letterbox to maintain the aspect ratio and add black bars to the sides of the video, as appropriate. Choose Stretch to force the video to fit the output frame size.

    • **Duration   **This option only appears if you choose a still image as a file source. Enter the length of time that you want the image to display. If you enter no duration, the image displays for one second.

  4. To add another file source, click Add and repeat step 3. To modify the file source information, select the source name in the list or select the source file thumbnail in the File Sources viewing area and make the changes in the File Source Settings section.

To apply and save presets

  1. Click the Presets tab.

  2. To choose a preset, do any of the following (hover the cursor over your choice to display its parameters):

    • If you want to apply a preset that is included with Expression Encoder, click the System tab. Locate the category of preset that you want to apply, expand the category until you see the preset, and then select it.

    • If you want to apply a preset that you saved, click the User tab. Locate and select the preset.

    • If you want to search for a particular preset, type a name or a partial name in the Search box, and then press Enter.

  3. Click Apply to apply the preset. Note that if you apply a preset, you don't need to set encoding options, which are explained in the next procedure. You can now just proceed to setting your metadata and output options. However, if you want to customize the preset, then you can make adjustments to it in the Encoding panel.

  4. If you want to specify a preset as the default preset, then, on the Option menu Cc294579.c043ff11-e91a-4d07-bccb-0d6f50e7d3cb(en-us,Expression.30).png, choose Set selected as default.

  5. To save any settings that you specify in the other panels, click the Option menu in the corresponding panel and then click Save panel as preset. Note that you are only saving the options you set in that panel, so you may want to name the preset with an intuitive name, such as "Metadata for company videos". When you apply a preset, it only applies those settings the panel that you saved the presets from. It does not change any other setting in any other panel.

To set encoding options

  1. Click the Encoding tab.

  2. Choose whether you want to encode audio, video, or both. For information about how to add captions for live broadcast, see the following task.


    If you choose to encode audio or video, make sure that you have chosen a corresponding live device in the Live Sources tab (see "To set live video sources" or "To set file-based sources," earlier in this topic).

  3. In the Video section, set the options according to the following descriptions:

    • Codec   Choose the type of codec that you want to use to compress your broadcast. VC1-Advanced is optimized for high-bit-rate encoding (20 Mb per second and up), although it is also effective with lower bit rates down to 2 Mb per second. VC1-Main is optimized for bit rates below 20 Mb per second. VC1-Simple is optimized for bit rates below 400 kb per second. All VC1 codecs provide high-quality encoding for both downloading and streaming content.

    • Bitrate   Drag this value to set an average bit rate for your broadcast. You can designate only one stream.

    • Frame Rate   Choose a frame rate for your broadcast.

    • Key frame interval   Drag the value to specify the number of seconds between keyframes. Use shorter values for video containing a lot of motion or scene changes. Use longer values for videos without much motion.

    • Buffer window   Specify the number of seconds of video that should be loaded into the buffer before the video plays.

    • Width and Height   Drag these values to adjust the dimensions of your video.

  4. In the Audio section, set the options according to the following descriptions:

    • Codec   Choose the type of codec that you want to use to compress the audio portion of your broadcast. Choose WMA for most situations. Choose WMA Professional to compress high-resolution, multiple-channel audio.

    • Bitrate   Specifies, in Kbps, the bit rate for the file. Increase the bit rate if audio is an important part of the file (for example, if the audio is a recording of a concert). To save file size and bandwidth, you may want to decrease this value if your audio consists only of speech, such as a talk show podcast.

    • Sample Rate   Specifies the number of samples per second in the audio file. You will get the best results if you set the sample rate to match the rate of your original file.

    • Bits Per Sample   Specifies the bit depth used when sampling.

    • Channels   Specifies the type of audio channels in your file. Most profiles feature only stereo.

  5. In the Advanced section, set the options according to the following descriptions:

    • Video Complexity   Specifies the encoding complexity of the video stream. This value can range from Fastest (0) to Best (5). Higher values give you higher-quality video but can require significantly more processing time. 0 and 1 are optimized for Live Encoding in which you have to process the frames in real time, and 2-5 are optimized for offline encoding.

    • Deinterlace Mode   Specifies whether interlaced video will be deinterlaced. Expression Encoder uses a deinterlacing method called bob, which uses field interpolation to build a full frame of video from a single field. Select Force Off to turn off deinterlacing. Select Auto bob to automatically apply deinterlacing when interlacing is present in the original source. Select Force bob to always apply deinterlacing.

    • Denoise   Select this option to reduce elements such as graininess and other noise in your video. This works for both file and live sources.

    • Noise Edge Removal   Select this option to remove noise from the edge of captured video.

    • Min Packet Size (Advanced)   Specifies the minimum size in bytes of User Datagram Protocol (UDP) packets that stream across the network. This setting applies to single bit-rate content that is streamed from a Windows Media server. Enter a value to represent, in bytes, the smallest packet size that Expression Encoder allows when streaming.

    • Max Packet Size (Advanced)   Specifies the maximum size in bytes of UDP packets that stream across the network. This setting applies to single bit-rate content that is streamed from a Windows Media server. Enter a value to represent, in bytes, the largest packet size that Expression Encoder allows when streaming.

To add metadata

  1. Click the Metadata tab in the Settings panel.

  2. Type your metadata in the appropriate boxes. The metadata that you add is present in the broadcast stream when you are performing a live broadcast, and is also stored with the file if you decide to archive it.

To add captions

  1. If you can't see the Script Commands panel, on the Window menu, click Script Commands.

  2. In the Type column, click the blank space and type a name for the caption. Then, in the Command column, click the blank space and type the exact text of the caption.

  3. Press ENTER. Note that a new row appears underneath the one that you are working with. Repeat Steps 2 and 3 for each caption that you want to create. After you have specified a type, you can choose it again from the menu, in order to prevent retyping it. Generally, you want your captions to be pertinent to your video or audio. This may be easier to do in advance if you know your source material, but if you are doing a live broadcast, you may want to add captions on the fly. In that case, you can follow these steps to add captions as you broadcast. Expression Encoder will execute these commands when you click the Send button next to the command as you broadcast. Instructions on how to do this are in the below procedure "To begin your Live Encoding presentation."

  4. To delete a row, click the Remove button.


    The caption will not display in the Output panel as you record your presentation. The caption displays only when the video is played back. However, if you decide to archive the file, you will see the caption text in addition to the corresponding marker when you open the file in the default view of Expression Encoder. You can then modify the caption text and the markers.

To set output options

  1. Click the Output tab in the Settings panel.

  2. Select the Streaming check box to enable the streaming settings.

  3. Select the streaming mode that you want to use. For an in-depth explanation of the streaming modes, see About streaming modes. Depending on what mode you select, specify the following options:

    • Broadcast   Enter a local port to which you want to send your streaming content. A remote client then pulls the content from the encoder using the port that you specify. For Max Connections, enter the maximum number of users you will allow to log on to your system.

    • Publishing Point   For Location, type the full address of the Media Services server to which you will be pushing content. You can generally use the syntax http://<ServerName>:<Port>/<PublishingPointName>. Click Pre Connect to enter any authentication information and establish a connection to the server. If you do not click Pre Connect now, you will be prompted for authentication information, if necessary, when you start your streaming session.

    • Launch Preview   Click this button to preview your broadcast in a Silverlight template. You cannot alter the template.

  4. If you want to save your streaming presentation as a file, select the File Archive check box and specify the following options:

    • Filename   Type a file name and output file path. To browse to a location, click BrowseCc294579.b2c2da7c-7d8d-4578-ae1f-4ee611d2a274(en-us,Expression.30).png.

    • **Append output to job on close   **Select this check box if you want to open the archived file as a new job in Expression Encoder. Once you finish your streaming broadcast and exit the Live Encoding mode, your archived file either appears as a job in the standard Expression Encoder workspace or, if you already opened a job before entering the Live Encoding mode, is appended to the open job. You can then apply other modifications to your file, such as adding markers, overlays, or a Silverlight template.

  5. Under Error/Frame Count, choose either of the following options:

    • In the On Error list, select the action that you want to occur when there is an error during streaming. To freeze the stream, select On Hold. To switch to another source, select Jump To, and then, in the list that appears underneath, choose the live or file source that you want to begin playing. To exit the streaming presentation, click Stop.

    • Select the Show frame count check box if you want to view a running count of the number of captured frames and the number of dropped frames in your broadcast. The numbers display underneath the live source window and underneath the Start button.

To begin your Live Encoding presentation

  1. Make sure that you have set all your options. To change any options, see the previous tasks.

  2. To cue your initial source, do one of the following:

    • If you want to begin with a live source, in the Live Sources viewing area, click Play in the appropriate source thumbnail. The Play label becomes the Cue label, and a green light next to the label will alert you that it is ready to play.

    • If you want to begin with a file source, in the File Sources viewing area, click the source that you want to stream first. A green light next to the Cue label will alert you that it is ready to play.

  3. Above the Settings panel, click Start. If you are pushing your content to a Windows Streaming server, and you have not already connected to it, you may be prompted now to enter authentication information.

  4. As your presentation records, do one of the following:

    • Click Play to activate various live sources.

    • Click Cue to activate any file source. Note that if one file source is still playing when you switch to another source, when you return to the first souce, it will resume playing at the point it was at where you switched sources.

  5. Monitor your performance in the Output panel. The viewer pane displays your live and file-based sources as they play, and the green bar to the right of the viewer pane displays the audio levels. If you set a video file source to Play then hold, when it has finished playing, the Restart button on the file thumbnail activates. Click this button to play the file again if you want to repeat it. Click Play on the live source thumbnail to activate that source.

  6. To mark a spot for a script command, such as a caption, to activate, click the Send button corresponding to the row that contains the command that you want to activate at the time that you want to activate it. When the broadcast is viewed, or the file is played back, the script command executes, or displays, until you click Send on another row.

  7. When you are finished, click Stop.

To modify your archived presentation

  1. After you have completed your streaming broadcasts, below the transport controls, click Exit Live Mode.

  2. Do one of the following:

    • If, on the Output tab in the Live Encoding Settings panel, you did not select the Append output to job on close check box, you must import your video in order to work with it. On the File menu, click Import and browse to the encoded file.

    • If, on the Output tab, you did select the Append output to job on close check box, you will see your encoded files listed in the Media Content panel as a single job or appended to a job that you already opened.

  3. You can now work with your files as you would with any other files that you import into Expression Encoder.

See also

Other resources

The Live Encoding workspace