Encoding RealVideo Clips RealVideo Encoder enables you to compress video files or input from a video device into one or more RealVideo formats. Output can be sent to a file or directly to RealServer for live broadcasting. You can select input files by browsing from within the Encoder, or you can drag-and-drop files for automated processing. The Encoder window displays information about input and output file formats and has fields for entering descriptive information. (UNIX users work in a command line environment.) This chapter details RealVideo Encoder operations, including supported input data formats, output options, and how to achieve the best possible audio and video quality. Some video editing programs can encode and write files in RealVideo format. For example a RealPlayer Plug-in is available for Adobe Premiere. There is a difference between encoding from a live source and broadcasting a live event. Live encoding requires special license purchased with your RealServer. For information about serving a live stream refer to Delivering Live Content. Source Files AVI Files QuickTime or .MOV files Producing High Quality Video Live Encoding Producing High Quality Audio Encoding Templates RealVideo Encoder Plug-in for Adobe Premiere 4.2 RealVideo Encoder for Windows RealVideo Encoder for Macintosh RealVideo Encoder for UNIX Creating Templates Source Files RealVideo content may be created either from previously recorded digital video files or from an external video source. The Encoder does not support compressed input files. Use a third-party editing utility to convert non-supported formats to a supported format. The following inputs are supported: AVI QuickTime AVI Files RealVideo Encoder accepts compressed or uncompressed format (it is recommended that you use uncompressed formats). The following are AVI requirements: The AVI file must have a color depth of 24-bits. Height and width must both be divisible by 16 or can be 150 x 120. Indeo drivers must be installed on your machine for the encoder to be able to open the AVI. Typically, if you captured the AVI on the same machine as the encoder, the encoder has no problem opening it. Otherwise the Indeo drivers are available from Intel. To determine if you have the AVI video codec for particular AVI file: Right-click the file name. Click Properties. Click the Details tab. Look at the Video Format field. If the Video Format field says "Unknown format" most likely the corresponding AVI video codec is not installed. If the Video Format field lists a format, click the Preview tab. You should be able to view the video in the preview window. Note: If you can preview the video, and still receive an error when encoding the AVI file, the file may not be in 24-bit color. You can convert the file to 24-bit file using a third-party video editing tool. QuickTime or .MOV files RealVideo Encoder accepts uncompressed 24-bit RGB QuickTime video files containing 8- or 16-bit mono and stereo audio. Image Size RealVideo Encoder 1.0 supports any size image that is a multiple of sixteen pixels. The most standard size is 176 pixels by 144 pixels. An image size of 150 x 120 is also supported. Producing High Quality Video To create the best possible streaming video, you must start with the best possible source material. Different video formats yield different qualities when digitized. Because RealVideo compression algorithms are lossy, some of the information contained in your original input is not included in the reconstructed signal sent to RealPlayer. The common video formats in order of quality are: Betacam-sp, also known simply as Beta. This format is common among video production professionals. Laserdisc S-VHS or Super-VHS VHS Satellite television services (e.g. Direct TV) have extremely high quality video. Their feed quality typically exceeds that of Laserdisc. Video playback devices commonly have two types of video outputs, S-video and composite. S-video produces better results. Video Capture Cards Before you can encode RealVideo, you must capture (digitize) your source material to your computer. To digitize video you need a video capture card. In general, any card that supports Video for Windows can be used. The following are capture cards that have been tested by RealNetworks: Video Capture Card Manufacturer Intel Smart Video Recorder Intel Wakeboard Multimedia Pro Digital Video Arts DC30 miro DC20 miro Bravado 1000 Truevision Osprey 100 MMAC Osprey 100 MMAC Note: If your video card has an audio input in addition to the video input, the audio input must go into the "line input" jack on the audio card, never into the video card. If your video card has both an s-video input and a composite input, use the s-video input. Computer Hardware When encoding video, the faster the computer, the faster the video and the fewer frames are dropped. A Pentium 150 MHz Windows 95 machine gives a good result. It is possible to use slower equipment, but anything slower than a Pentium is not recommended. Capturing video puts a burden on your computer's ability to write to your hard drive. Seagate manufactures special hard drives for capturing video called AV drives. If you do not use one of these special drives, frames may be dropped during the capture process when the hard drive re-calibrates itself periodically. If you experience dropped frames with a standard drive, you can re-capture the video. Live Encoding The quality of live encoding depends on the power of your computer system. Encoding at higher quality takes longer and requires greater computing resources than encoding at a lower quality. Slower machines give reasonable results in Slide Show mode, at 1 fps or less. The following lists the minimum requirement tested as well as the recommended hardware. Requirement Minimum Recommended CPU Pentium 150 Dual-Pentium Pro 200 OS Windows 95 Windows NT RAM 32 MB< 64 MB Hard Drive 3 MB AV drive, 3 MB The following lists the recommended settings for a variety of different content types: Content Type Total Bit rate Audio codec Frames/sec Quality Setting General 20 6.5 2 100 General 20 6.5 7.5 70 Newscast 20 6.5 4 100 Newscast 45 8.5 10 1 Music 20 12 5 100 Music 45 16 5 70 For low frame-rate live encoding, less than 3 fps, a P166 or better computer, running Windows 95, is required. Any capture board with captures a Video for Windows format of YUV9 or RGB 24 (preferred) will work. If you are not getting the desired frame rate, lower the quality setting. Live Capture-to-File If you have a real-time capture station, you can use it to capture and compress directly into RealVideo format. To do this, use your live feed or the output of a video player (Beta, S-VHS, Laser Disc, etc.) and set the encoder to capture to file instead of capture to a live server feed. This has the advantage of eliminating the need to create and store intermediate AVI files which are very large and take considerable disk space. It is also the fastest way to capture for things like breaking news clips when time-to-post is important. Editing Limited video editing tools are available with RealVideo. For more information, refer to Editing RealVideo Files. For more advanced editing features the following programs are recommended: Adobe Premiere In:sync Kohesion Producing High Quality Audio Use high quality source files. When possible, digitize the sound to a supported file format. Then pre-process the file with a sound editing program. Set the amplitude of your input signal to maximize the use of the available dynamic range. Eliminate any DC offset either while recording content or later with an audio editor. This removes low frequency noise. Use a CD quality sampling rate (44.1 kHz), sampling width (16-bit) and two channels when creating an input file. You can always downsample and convert to one channel later. The source files should contain signals of the maximum allowable amplitude. If the full amplitude range is not used, the resulting RealVideo files may sound flat. Adjust the range using a sound editor before encoding the file. Some sound editors have a Normalize function that maximizes levels automatically. If your original audio file signal exceeds the acceptable amplitude range, the file may contain "clipping." Clipping can give rise to clicks or pops on playback. If your source file contains a clipped signal, your final RealVideo file will have high-frequency background noise or static. When encoding live-source audio, you have less opportunity to manipulate your input signal. Be sure that volume levels are prepared and tested. If you are not doing a live broadcast, you may want to record your input as a .wav or .au file so that you may digitally edit it prior to compression. Cut any unnecessarily long silences from the beginning or end of the output file to conserve space. For an in-depth discussion concerning pre-processing, read "Improve Sound Quality in RealVideo Clips" on the RealNetworks Web site: http://www.real.com/help/ Encoding Templates Before you begin encoding, you must make decisions about the appropriate settings for different types of audio and video input. RealNetworks has supplied several pre-defined encoding templates to assist users in making those decisions. You can select from the pre-defined templates, adjust those templates or define a new template for the type of content you are encoding. For a list of templates, refer to Pre-Defined Templates. For information about creating templates, refer to Creating Templates. Each template is optimized for a particular type of audio and video content as well as for bandwidth. Select one or more templates that best suit your needs. RealServer can deliver clips encoded using multiple templates. In this way, you can reach the widest possible audience while still providing high-bandwidth users with the best listening experience. Using Bandwidth Negotiation, you can configure your site to automatically serve the appropriately encoded file. For more information about Bandwidth Negotiation, refer to Managing Content on RealServer. Pre-Defined Templates Below are the default settings for some common content types found in RealVideo Encoder. If one of the following templates does not achieve the effect you are looking for, try creating a new template by basing it on a pre-defined template and then modifying the settings. Note: It is recommended that you do not modify the pre-defined templates. If you want to change some of the settings, save the template as a new template. This way, you do not overwrite the pre-defined templates. Template Name Target Bandwidth Audio Codec Video Bit Rate (Kbps) Total Bit Rate (Kbps) Video Quality Frame Rate (fps) High Action 28.8 w/ Music 28.8 8 Kbps music 11.0 19 100 .25 High Action 28.8 w/ Voice 28.8 6.5 Kbps voice 12.5 19 100 .25 Music Video 28.8, Emphasize Audio 28.8 12 Kbps music 7 19 100 .25 Music Video 28.8, Emphasize Video 28.8 8 Kbps music 11 19 100 .25 Talking Heads 28.8 28.8 6.5 Kbps voice 12.5 19 100 7.5 High Action 56 (Fractal) 56.0 8.5 Kbps voice 36.5 45 70 10 High Action 56 w/ Music 56.0 16 Kbps music, High response 29 45 100 7.5 High Action 56 w/ Voice 56.0 8 Kbps voice 36.5 45 100 7.5 Music Video 56, Emphasize Audio 56.0 16 Kbps music, High response 29 45 100 7.5 Music Video 56, Emphasize Video 56.0 12 Kbps music 33 45 100 7.5 Talking Heads 56 56.0 8.5 Kbps voice 36.5 45 100 7.5 High Action, 112, (Fractal) 112 12 Kbps music 78 90 70 15 * Target Bandwidth indicates the minimum bandwidth necessary to play the file: 28.8 corresponds to a 28.8 Kbps modem 56.0 corresponds to an ISDN or 56 Kbps modem 112 corresponds to a Dual ISDN or T1 line RealVideo Encoder Plug-in for Adobe Premiere 4.2 RealVideo Encoder Plug-in for Adobe Premiere 4.2 exists for both Windows and Macintosh platforms. Currently, the Windows version is installed by RealVideo Encoder 1.0. The Macintosh version of this plug-in can be downloaded independently from RealNetworks Web site. The Windows Adobe Premiere plug-in is installed in the /Premiere/plugins directory. The Macintosh Adobe Premiere plug-in is installed in the plug-in directory in the Premiere folder. The RealVideo Encoder Adobe Premiere plug-in does not work with Adobe Premiere LE because Premiere LE does not support third party plug-ins. Supported File Formats RealVideo Encoder Plug-in for Adobe Premiere supports all of the file types supported by Adobe Premiere. Movie File Formats Audio File Formats Video for Windows (.avi) Audio Interchange (.aif) QuickTime for Windows and Macintosh (.mov) Windows Waveform (.wav) FilmStrip (.flm) Audio source files must be sampled at 11, 22, or 44 kHz. 8-bit and 16-bit mono and stereo audio files are supported. Encoding with Adobe Premiere 4.2 To encode audio and video files in Adobe Premiere 4.2: Start Adobe Premiere 4.2. Click Open from the File menu Select one of the supported file types. The file appears in the Clip window. Select the Clip window. Click Export from the File menu and select RealVideo Encoder. RealVideo Encoder Options window appears (Windows version): In the media options pane, select one of the pre-installed styles. These styles are guidelines for creating content containing both audio and video. You can save your own styles, or delete styles that you do not use. If you delete a style you created yourself, it will be permanently deleted. If you delete a style which was installed by RealVideo Encoder, you can get it back by reinstalling RealVideo Encoder. Once you have selected a style, you can change any of the settings for the audio codec, the video codec, the total bit rate, the Quality, or the Frame Rate. In the properties pane, enter the Title, Author, and Copyright information for your output file. These fields are optional. RealPlayer users with low bandwidth modems can experience files encoded for a higher bandwidth by partially downloading audio data before beginning playback. If you want to allow this, click the Allow PerfectPlay checkbox. This is the default setting. If you want to allow RealPlayer Plus users to save your clip to disk, click the Allow Selective Record checkbox. In the Marker Options frame, click the appropriate option. Refer to Marker Options for more information. In the destination pane, click Select and enter the name of the output file. Click the Encode button. Adobe Premiere begins encoding the file. When the file is encoded, a Status dialog box appears, providing details about the encoded file. Click the OK button. Play the encoded file using RealPlayer 4.0. Marker Options Marker options allow you to take advantage of the Marker feature in Adobe Premiere. Click Off to encode the entire clip regardless of markers. Choosing this option means that you do not have control over which frames get encoded. Click Key Frames to encode a marked file. Choosing this option will ensure that all frames that are marked are encoded Click Slide Show Frames to encode only the marked frames. Choosing this option allows you to create slide shows out of video files and gives you control over exactly which frames you want to use. Refer to your Adobe Premiere documentation for information on how to set and clear numbered and unnumbered markers. The plug-in recognizes both Premiere's numbered (up to 10 available) and unnumbered markers (up to 1000 available). Using RealVideo Encoder for Windows RealVideo Encoder for Windows can do static and live encoding. Whether or not you will be able to do live encoding depends on the license key for your RealServer. RealVideo Encoder 1.0 converts video in common file formats to RealVideo format. You specify the input source and output file, and you can specify options such as the compression type and copyright string to be included in the output file. For a list of supported input formats, see Source Files. RealNetworks has supplied several pre-defined encoding templates to assist users in determining the appropriate settings for different types of video input. You can select a pre-defined template or define a template specifically for the type of video you are encoding. For more information, refer to Encoding Templates and Creating Templates. Note: If you have the appropriate license key for RealServer, RealVideo Encoder can deliver live content for broadcasting live events. For information about RealVideo Live Encoder for Windows, refer to Using the Live Encoder for Windows. To encode a file using RealVideo Encoder for Windows: Start RealVideo Encoder 1.0. RealVideo Encoder window opens: Click Open Session from the File menu. The Open Session window appears: In the source pane, ensure that File is selected. Click the Add button. The Add Source File dialog box appears. Select the file you want to encode. Click the Open button. In the destination pane, ensure that a check appears in RealMedia File checkbox. Click the Select button. The Select Destination File dialog appears. Enter the destination file name. Click the Save button. Click the OK button. The Open Session window closes. In the properties pane, enter the Title, Author, and Copyright information for your output file. These fields are optional. If you want to allow RealPlayer Plus users with low bandwidth modems to experience RealVideo files encoded for a higher bandwidth by partially downloading video data before beginning playback, click the PerfectPlay checkbox. If you want to allow RealPlayer and RealPlayer Plus users to save your RealVideo signal to disk, click the Selective Record checkbox. In the templates pane, select the templates with which to encode the file. For more information, refer to Encoding Templates. If you want to create your own template, click the Advanced button. Refer to Creating New Templates. Click the Start button to start the encoding process. When the file is encoded, an Encoding Complete message appears indicating the bit rate achieved. Note: If RealVideo Encoder is unable to encode the file within the selected bit rate, a message window appears. If the final bit rate is not acceptable to your needs, you need to re-encode the file with a different template. Select Volume Control from Options. The Volume Control window displays. You can adjust the volume using the control. Select Crop Input Image from Options. The Image Cropping window displays. Notice the crop lines around the image. These lines show the portion of the image that will be encoded. Use the Left, Top, Width, and Height up-and-down arrows to adjust the size and locaation of the crop lines. View the encoded file with RealPlayer 4.0. Drag-and-Drop Encoding for Windows RealVideo Encoder for Windows supports drag-and-drop encoding: Click an input-video-file icon and drag it onto an open Encoder window. This enters path and file name information into the appropriate Encoder fields. Then, you only need to enter the descriptive information and settings and click the Start button to begin the encoding process. Command Line Encoding for Windows In some situations you may find it convenient to encode within the DOS command line environment by creating a batch file to automate the encoding of many separate input files. You can specify command line arguments that direct the Encoder to process an input file and then shut down. The syntax is: ENCODER file_to_encode [settings_file] where file_to_encode is the digital audio input file and settings_file is an optional file in which you have saved your encoding preferences. For example, the command: ENCODER one.wav prefs.txt encodes the file one.wav using the Encoder settings specified in the file prefs.txt. If you place the files you want to encode and the corresponding settings files in the same directory as RealVideo Encoder, you do not have to specify file paths. However, if you want to encode files in other directories, you need to specify the complete paths to these files. Likewise, if your working directory is not the one in which your Encoder is installed, you need to specify its location. For example, the command: C:\raencode\encoder C:\docs\one.wav C:\prefs.txt creates one.ra in the directory C:\docs from within any working directory. RealVideo Encoder options for Windows are described below: Option Description (defaults in parenthesis) /I Use this option to specify an Input File /O Use this option to specify an outfile or dir - Output File Name or Directory (infile.rm or dir\YYYYMMDDHHMMSS.rm) /L Use this option to specify Use Live Input (ignores /I) /S Use this option to specify "server[:port]/file" - Server Name, Port and File (port defaults to 7070) /W Use this option to specify password - Server Password /D Use this option to specify hhh:mm:ss - Maximum Encoding Duration (continuous) /A Use this option to specify an Audio Codec (0) /V Use this option to specify a Video Codec (0) /F Use this option to specify a framerate - Frame Rate (optimal) /B Use this option to specify Total Kbps for clip (100) /Q Use this option to specify Quality 1-100 (100) /T Use this option to specify a Clip Title /U Use this option to specify a Clip Author /C Use this option to specify a Clip Copyright /P Use this option to Enable Perfect Play 0-1 (1) /R Use this option to Enable Selective Record 0-1 (0) /X Use this option to Enable Audio Encoding 0-1 (1) /Y Use this option to Enable Video Encoding 0-1 (1) /? Use this option to Display this help information Settings File The settings file allows you to specify Compression, Selective Record, PerfectPlay, and Title, Author, and Copyright strings for the .ra file. Any setting not specified within the settings file take the values specified as the default settings within the Encoder. Setting Options Title Text you want to appear as the Title of the RealVideo file. Default: blank Author Text you want to appear as the Author of the RealVideo file. Default: blank Copyright Text you want to appear as the Copyright of the RealVideo file. Default: blank Codec This is the Codec with which to encode and decode this file. Valid options are: Codec Algorithm lpcJ RealVideo 2.0 - 14.4 28_8 RealVideo 2.0 - 28.8 DNET RealAudio 3.0 algorithms Default: DNET Flavor This is the Flavor of the Codec. Depending on the Codec chosen valid options are: Codec Flavor Algorithm lpcJ 0 RealVideo 2.0 - 14.4 28_8 0 RealVideo 2.0 - 28.8 DNET 0 RealAudio 3.0 - 28.8 Mono, narrow response DNET 1 RealAudio 3.0 - 28.8 Mono, medium response DNET 2 RealAudio 3.0 - 28.8 Mono, full response DNET 3 RealAudio 3.0 - 28.8 Stereo DNET 4 RealAudio 3.0 - ISDN Mono DNET 5 RealAudio 3.0 - ISDN Stereo DNET 6 RealAudio 3.0 - Dual ISDN Mono DNET 7 RealAudio 3.0 - Dual ISDN Stereo Default: 2 SelectiveRecord This determines if a RealPlayer Plus program user is able to record the RealVideo file. Valid options: 0 Disabled 1 Enabled Default: 0 PerfectPlay This determines if a RealPlayer Plus program user is able to use PerfectPlay. Valid options: 0 Disabled 1 Enabled Default: 1 Example Settings File: [Default Settings] Title = My Song Author = RealNetworks Copyright = 1996 Codec = DNET Flavor = 3 SelectiveRecord = 1 PerfectPlay = 1 Note: The settings file must start with the [Default Settings] line; all other lines are optional. Any option you do not specify in the settings file is set to the default setting. Using RealVideo Encoder for Macintosh RealVideo Encoder for Macintosh can only do static encoding at this time. RealVideo Encoder 1.0 converts video in common file formats to RealVideo format. You specify the input source and output file, and you can specify options such as the compression type and copyright string to be included in the output file. For a list of supported input formats, see Source Files. RealNetworks has supplied several pre-defined encoding templates to assist users in determining the appropriate settings for different types of video input. You can select a pre-defined template or define a template specifically for the type of video you are encoding. For more information, refer to Encoding Templates and Creating Templates. To encode a file using RealVideo Encoder for Macintosh: Double-click RealVideo Encoder icon. RealVideo Encoder window opens. Select Open Session from the File menu. The Open Session window appears. In the source pane, ensure that File is selected. Click the Add button. The Add Source File dialog box appears. Select the file you want to encode. Click the Open button. In the destination pane, ensure that a check appears in RealMedia File checkbox. Click the Select button. The Select Destination File dialog appears. Enter the destination file name. Click the Save button. Click the OK button. The Open Session window closes. In the properties pane, enter the Title, Author, and Copyright information for your output file. These fields are optional. If you want to allow RealPlayer Plus users with low bandwidth modems to experience RealVideo files encoded for a higher bandwidth by partially downloading video data before beginning playback, click the PerfectPlay checkbox. If you want to allow RealPlayer and RealPlayer Plus users to save your RealVideo signal to disk, click the Selective Record checkbox. In the templates pane, select the templates with which to encode the file. For more information, refer to Encoding Templates. If you want to create your own template, click the Advanced button. Refer to Creating New Templates. Click the Start button to start the encoding process. When the file is encoded, an Encoding Complete message appears indicating the bit rate achieved. Note: If RealVideo Encoder is unable to encode the file within the selected bit rate, a message window appears. If the final bit rate is not acceptable to your needs, you need to re-encode the file with a different template. View the encoded file with RealPlayer 4.0. Command Line Encoding for Windows In some situations you may find it convenient to encode within the DOS command line environment by creating a batch file to automate the encoding of many separate input files. You can specify command line arguments that direct the Encoder to process an input file and then shut down. The syntax is: ENCODER file_to_encode [settings_file] where file_to_encode is the digital audio input file and settings_file is an optional file in which you have saved your encoding preferences. For example, the command: ENCODER one.wav prefs.txt encodes the file one.wav using the Encoder settings specified in the file prefs.txt. If you place the files you want to encode and the corresponding settings files in the same directory as RealVideo Encoder, you do not have to specify file paths. However, if you want to encode files in other directories, you need to specify the complete paths to these files. Likewise, if your working directory is not the one in which your Encoder is installed, you need to specify its location. For example, the command: C:\raencode\encoder C:\docs\one.wav C:\prefs.txt creates one.ra in the directory C:\docs from within any working directory. RealVideo Encoder options for Windows are described below: Option Description (defaults in parenthesis) /I Use this option to specify an Input File /O Use this option to specify an outfile or dir - Output File Name or Directory (infile.rm or dir\YYYYMMDDHHMMSS.rm) /L Use this option to specify Use Live Input (ignores /I) /S Use this option to specify "server[:port]/file" - Server Name, Port and File (port defaults to 7070) /W Use this option to specify password - Server Password /D Use this option to specify hhh:mm:ss - Maximum Encoding Duration (continuous) /A Use this option to specify an Audio Codec (0) /V Use this option to specify a Video Codec (0) /F Use this option to specify a framerate - Frame Rate (optimal) /B Use this option to specify Total Kbps for clip (100) /Q Use this option to specify Quality 1-100 (100) /T Use this option to specify a Clip Title /U Use this option to specify a Clip Author /C Use this option to specify a Clip Copyright /P Use this option to Enable Perfect Play 0-1 (1) /R Use this option to Enable Selective Record 0-1 (0) /X Use this option to Enable Audio Encoding 0-1 (1) /Y Use this option to Enable Video Encoding 0-1 (1) /? Use this option to Display this help information Settings File The settings file allows you to specify Compression, Selective Record, PerfectPlay, and Title, Author, and Copyright strings for the .ra file. Any setting not specified within the settings file take the values specified as the default settings within the Encoder. Setting Options Title Text you want to appear as the Title of the RealVideo file. Default: blank Author Text you want to appear as the Author of the RealVideo file. Default: blank Copyright Text you want to appear as the Copyright of the RealVideo file. Default: blank Codec This is the Codec with which to encode and decode this file. Valid options are: Codec Algorithm lpcJ RealVideo 2.0 - 14.4 28_8 RealVideo 2.0 - 28.8 DNET RealAudio 3.0 algorithms Default: DNET Flavor This is the Flavor of the Codec. Depending on the Codec chosen valid options are: Codec Flavor Algorithm lpcJ 0 RealVideo 2.0 - 14.4 28_8 0 RealVideo 2.0 - 28.8 DNET 0 RealAudio 3.0 - 28.8 Mono, narrow response DNET 1 RealAudio 3.0 - 28.8 Mono, medium response DNET 2 RealAudio 3.0 - 28.8 Mono, full response DNET 3 RealAudio 3.0 - 28.8 Stereo DNET 4 RealAudio 3.0 - ISDN Mono DNET 5 RealAudio 3.0 - ISDN Stereo DNET 6 RealAudio 3.0 - Dual ISDN Mono DNET 7 RealAudio 3.0 - Dual ISDN Stereo Default: 2 SelectiveRecord This determines if a RealPlayer Plus program user is able to record the RealVideo file. Valid options: 0 Disabled 1 Enabled Default: 0 PerfectPlay This determines if a RealPlayer Plus program user is able to use PerfectPlay. Valid options: 0 Disabled 1 Enabled Default: 1 Example Settings File: [Default Settings] Title = My Song Author = RealNetworks Copyright = 1996 Codec = DNET Flavor = 3 SelectiveRecord = 1 PerfectPlay = 1 Note: The settings file must start with the [Default Settings] line; all other lines are optional. Any option you do not specify in the settings file is set to the default setting. Using RealVideo Encoder for UNIX RealVideo Encoder for UNIX is run from the command line using the following syntax: rvencoder options where options are any of RealVideo Encoder options described below. Option IDTH=430>IDTH=430>Description -I Use this option to specify an Input File -O Use this option to specify an Output File -A Use this option to specify an Audio Codec* -V Use this option to specify a Video Codec* -F Use this option to specify a Frame Rate -B Use this option to specify a Total Kbps for clip -Q Use this option to specify a Quality 1-100 -T Use this option to specify a Clip Title -U Use this option to specify a Clip Author -C Use this option to specify a Clip Copyright -P Use this option to specify Enable Perfect Play, 0 = Off, 1= On -R Use this option to specify Enable Selective Record, 0 = Off, 1= On -X Use this option to specify Enable Audio Encoding, 0 = Off, 1= On -Y Use this option to specify Enable Video Encoding, 0 = Off, 1= On -H Use this option to specify display this help information *The list of audio and video codecs is displayed when you type RVEncoder -H; use the number of the codec when choosing a codec using the -A and -V flags. +Frame rate is in frames per second and may a contain decimal, for example F7.5. By default, RealVideo Encoder for UNIX displays a progress indicator on your screen as the file is encoded. If you plan to encode large numbers of files on a regular schedule, you can write a shell script for batch encoding. The following is an example of the command line: rvencode -i foo.mv -A 2 -V 0 -F 1.0 -B 40 -Q 100 -T The Title -P 1 This example encodes a movie file using audio codec 2, video codec 0, at 1 frame per second, a video quality of 100, a target bandwidth of 40 Kbps, and with PerfectPlay enabled. Creating Templates Each template is comprised of an audio codec, video bit rate, total bit rate, quality and frame rate. The quality of RealVideo encoding is affected by these settings and by the actual content. Below are content elements that can affect the quality of a video encoding at 19 Kbps: Content Type Expected Encoding Results Fixed camera shot, low motion Clean frames, with high frame rates Fixed camera shot, medium motion Clean frames, somewhat lower frame rates Multiple camera shots, low motion Clean frames with 1 fps or less Zoom with low motion Clean frames with moderate frame rate Fixed camera shot, high motion Clean frames with moderate frame rate Multiple camera shots, high motion Clean frames with less than 1 fps Subjective results based on content elements RealVideo encoder produces significantly better frames with higher frame rates when used with bandwidths higher than 28.8 Kbps. When deciding which parameters to set, the total bit rate must be considered. The total bit rate is the actual bit rate at which the AVI is encoded. If the target bit rate is 28.8 Kbps, then the total bit rate should be 19 Kbps. The following are the recommended total bit rates for common bandwidths. Target Bit Rate Total Bit Rate 28.8 Kbps 19 Kbps 56.0 Kbps 45 Kbps 64.0 Kbps 56 Kbps 128.0 Kbps 105 Kbps Target and total bit rates After selecting the total bit rate according to the table above, choose an audio codec. Audio Algorithms 6.5 Kbps voice 8 Kbps music 8.5 Kbps music 12 Kbps music 15.2 Kbps voice 16 Kbps music High response 16 Kbps music Low response 16 Kbps music Medium response 20 Kbps music stereo 40 Kbps music mono 40 Kbps music stereo 80 Kbps music mono 80 Kbps music stereo Since RealAudio codecs have discreet bandwidths, the video bit rate is the difference between the total bit rate and the bit rate of the chosen audio codec: Video Bit Rate = (Total Bit Rate) - (Bit Rate of Audio Codec). In RealVideo Encoder, the video bit rate is calculated automatically. Next choose a frame rate. Not all content types support high frame rates for a given bandwidth. The highest frame rate that can be achieved at 19 Kbps is 7.5 frames per second (fps) for Talking Head type content. Different content types require different frame rates. For example, while Talking Heads at 19 Kbps might support 7.5 fps, music videos only support 1 fps or less. Creating New Templates To create a new template: In the templates pane, click the Advanced button. The Advanced Setting window appears: Enter the name of the new template in the Template Name field. Note: It is recommended that you do not modify the pre-defined templates. If you want to change some of the settings, save the template as a new template. This way you do not overwrite the pre-defined templates. Select an Audio codec. Select a Video codec. RealVideo Encoder 1.0 has two video codecs available, RealVideo (Standard) and RealVideo (Fractal). The bit rate of RealVideo 1.0 codec varies depending on the video codec and total bit rate selected. Select the total bit rate for the encoded video file. Select the Quality by moving the slider. Select the Frame Rate by moving the slider. When using the RealVideo Standard video codec, you can select Optimize Frame Rate to let the encoder automatically select the frame rate. Click the Save button to save the template or click the Apply button to apply the settings without saving the template. Click the Close button to close the Advanced Settings window.

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