RealProducer Plus comes with a variety of options that allow you to create RealMedia suited to your needs. This chapter discusses how to change different recording preferences, how to adjust the settings for target audiences, and how to change audio and video capture settings.
RealProducer Plus gives you the option to modify settings that affect all recording sessions. This section shows you how to change general recording preferences, SureStream preferences, and live broadcast settings. You use the Preferences dialog box to make these adjustments.
The General page of the Preferences dialog box allows you to change properties about files you create, start-up options, and the temporary storage directory used by RealProducer Plus.
By changing file properties, you are allowing RealPlayer Plus users to be able to record your RealMedia clip during playback, download your RealMedia clip to their hard drive, disallow search engines to find your clip, and add rating information to your clip. These settings are used for each clip you create.
Selecting the Allow Recording preference allows RealPlayer Plus users the option of recording the playback of your RealMedia clip onto their computers. When your clip is played, the user clicks the Record button and your clip is saved on the user's machine. Deselecting this preference disables the Record button for RealPlayer Plus users.
Selecting the Allow Download preference gives any user--even those without a RealPlayer--the ability to download your RealMedia clip directly onto their hard drive.
Selecting the Files Should Not Be Indexed By Search Engines preference disables the ability for search engines to point users to your clip. When deselected, search engines will use keywords that you add to the clip. See "Creating Keywords" for more information.
You can also choose to give your clip a rating for its content. The following list describes the different Audience Ratings:
During a recording session, RealProducer Plus uses a directory to store media files prior to creating the final RealMedia clip. Using the Preferences dialog box, you can change the directory used for this purpose.
The SureStream page of the Preferences dialog box allows you to change different options when you record SureStream clips. You can create a separate stream for older versions of the Player, and you can decide whether audio or video quality should be given priority during reduced bandwidth conditions.
RealProducer Plus allows you to record RealMedia clips that can be played on both the current version of RealPlayer and version 5.0. During the recording process, RealProducer Plus creates a stream for each version. However, you will still need a RealServer to stream the clip.
We recommend that you select this option only if you are sure that you need compatibility. Not selecting the option will limit file size and processing time.
This option allows you to choose whether your clip will emphasize audio or video when a RealPlayer's connection degrades and must switch to a lower bandwidth stream. Choosing audio means that video quality will be sacrificed before audio quality. Choosing video means that audio quality will be sacrificed before video quality.
These settings are used for any live broadcast you create with RealProducer Plus. They control the protocol that you will use to connect to your server during the broadcast.
You have two choices for connecting to a server:
You can adjust how video data is converted into RealVideo. Using a number of controls, advanced users can fine-tune how video data is filtered, compressed, and encoded into streaming video.
When RealProducer Plus receives video input from a video capture card or from a video file, it first passes the data through different video filters. These filters can remove video "noise," remove unnecessary video frames, and remove video "artifacts" created when the original video was converted into digital video.
Using the filters will generally result in higher quality output clips.
Video noise appears as distortions (blotches) in your input video. This noise can appear in video for a variety of reasons: poor capture cards, cameras, or storage. The noise filter removes this noise from the input video prior to recording.
When you resize input video, you can introduce blurring or aliasing into the video data. The resize filter can remove these problems and create a smoother picture.
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| Use the High Quality Resize filter when high bit rate video is resized. |
Movie film is photographed generally at 24 frames per second (fps). When a film is converted into digital video at 30 fps, extra frames are added by merging frames together or copying entire frames. The film-to-video conversion process is called telecine.
The inverse-telecine filter looks for frames added during a telecine process and removes them, thus eliminating redundant encoding and improving the quality of the frames that are encoded.
This filter removes "artifacts" that can be introduced when encoding NTSC or PAL formatted video. These artifacts are usually a jaggedness surrounding a moving object.
These settings adjust how the video data is encoded by the RealProducer Plus video codec. You can choose what video codec to use, set the codec to analyze the video prior to encoding, increase quality by varying the bit rate, and protect against packet loss.
RealProducer Plus allows you to choose what version of RealVideo you will use to create your streaming media clips. Each version uses different methods to compress your original video data into a format that is best for streaming. The following table gives you a brief description of each version.
| Codec Name | Description |
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| RealVideo G2 | A basic RealVideo codec that works with all RealPlayer versions from G2 and higher. |
| RealVideo G2 with SVT | A RealVideo codec with Scalable Video Technology (SVT); compatible with RealPlayer versions 6.0.6 and above. For more information about SVT, see "About RealVideo with SVT" below. |
| RealVideo 8.0 | This RealVideo codec provides the best quality output for all bit rates, but uses more processing power than the other codecs. It is compatible with RealPlayer 8 and above. Your audience's RealPlayers must update before they can view clips created with this codec. |
When you select RealVideo with SVT, RealProducer Plus creates RealVideo clips that can automatically adjust the following according to the audience's connection and computer processing speed:
Frame Rate-you can create video clips and not worry about the audience's computer speed. If the clip is unable to keep the frame rate on a user's machine, it will gradually reduce the frame rate needed to maintain clear video.
Frame Size-create clips for vastly different bit rates without worrying about the size of the image. RealVideo with SVT creates the optimal frame size for each stream, based on bit rate and other video settings.
Data Loss-if packets are lost during video delivery, special packet that correct errors are sent to reconstruct the lost data.
Two-pass encoding increases quality of output video by analyzing video data before encoding the input video. The first pass analyzes the entire clip, looking for transitions and overall complexity. The second pass encodes the clip using the analysis from the first pass. Using this feature will increase encoding time.
When you use two-pass encoding, no video appears in the video preview window during the first pass.
This feature enables the video codec to vary the bit rate throughout the clip depending on the type of content being encoded. More bits are spent on high-action scenes, taking away bits from low-action scenes.
When you select this feature, you make the output video more resilient to "lossy" environments. A lossy environment is when packets of streaming video data are lost during transition from the server to the player. Bad phone lines or heavy network traffic can both create a lossy environment.
These features allow you to fine-tune the encoded output video, but should only be used by an expert. Adjusting these settings incorrectly can seriously degrade your output video.
If you selected to use VBR encoding in the Video Codec tab, you can also specify the maximum time that latency will occur before the clip begins.
Keyframes are used to reset a video image during encoding. All other frames are created for minor adjustments between the keyframes. This setting allows you to specify how frequently the video is reset.
Note that more frequent keyframes may increase the bit rate needed to stream the output clip. Otherwise, the quality of the video is decreased.
RealProducer Plus gives you the option to adjust the settings for a particular target audience. Each target audience setting is an array of various codecs (compression/decompression algorithms) and other settings that work best for that particular target bit rate.
The quality of the recorded output is affected by these settings and by the actual content (for example, fixed camera shots, amount of motion, and multiple camera shots).
There are two types of target audience settings: settings for video clips, and settings for audio-only clips. The following sections describe how to modify each type of setting.
Target audience settings for video clips are used to determine how RealProducer Plus creates RealMedia from your combined audio and video input when various target audiences are selected. These settings include an audio codec, a video codec, maximum frame rate, and target bit rate.
The Target Audience Settings - Video Clips dialog opens to the Audio page.
When you select a codec, read the description below. This helps you determine whether the codec is appropriate for the target audience. The frequency response supported by the codec is also listed.
At lower values, the output emphasizes image clarity at the expense of smooth-looking motion. For example, if your content contains a lot of motion and you set the slider closer to the 7.5 fps setting, the resulting video image will be clearer, but will exhibit choppier motion.
You cannot set the frame rate higher than the input file's frame rate.
Generally, you should reduce the expected total bit rate by 25% to compensate for connection and packet overhead. For example, choose 20 Kbps for a 28.8 Kbps modem.
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| You can click Restore Defaults at any time during the above steps to delete your changes and return the target audience to its original settings. |
Target audience settings for audio clips are used to determine how RealProducer Plus creates RealAudio from your audio-only input when various target audiences are selected. These settings include an audio codec and whether you are creating a stand-alone clip, or for use in a multimedia presentation with other RealMedia (RealVideo, RealPix, and RealText).
When you select a codec, read the description below. This helps you determine whether the codec is appropriate for the selected target audience.
RealProducer Plus allows you to make other changes to how video is recorded during a session. You can crop out sections of the video input you don't want to record or resize the output.
RealProducer Plus's cropping feature allows you to record any portion of a video image that you wish. By cropping an image, you can reduce the overall bit rate of your recorded clip while removing unnecessary image space.
The smallest size that you can crop an image to is 32 x 32.
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| You can also select from a list of crop settings used previously. |
RealProducer Plus supports any size image from any video source, but it will automatically crop the height and width to multiples of 4. The most common video image sizes are 160 x 120, 176 x 144 pixels, or 320 x 240 pixels.
We recommend that you do not resize video while capturing live video to a file. In these cases, use your video capture card's settings to change video size.
The Video Settings dialog box opens with the current output size listed at the top.
The Encoded Output will change to reflect what you enter. All values will be rounded to multiples of 4.
