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RealVideo® User Guide
Including RealVideo® files in your site
Unix Professional and Unix Premier accounts include the use of the popular RealVideo® server.
STEP 1: CAPTURE THE VIDEO FILE
In order to to encode the RealVideo files, the video must first be in a format that the RealVideo encoder can use. The video that you have must be captured in the one of the following formats.
VHS, Beta or Laser Disc can be the source for the actual video content to capture. Consult your video capture card documentation on how to capture video in to AVI or QuickTime formats.
- NOTE:
RealVideo supports any frame size with a height and width that are multiples of 16. The RealVideo encoder will also accept a 160x120 image size. When creating content, it is recommend to use a frame size of 176x144. Most video capture cards do not support this size. Indeo drivers must be installed on your machine for the encoder to be able to open the AVI. If the AVI file was captured with the same machine there is usually no problem. You can locate the INDEO drivers at this location; http://developer.intel.com/ial/indeo/video/
STEP 2: CREATE THE REALVIDEO FILE
You must have the RealVideo encoder to encode Video for the RealVideo server. You can download a copy of the encoder from http://www.real.com/
You must set three Parameters when encoding the RealVideo file: Audio codec,
video bit rate, and frame rate. The quality of the video file depends on these three settings.
First choose the bit rate for the video. See table below.
| Targeted Modem Rate |
Total Bit Rate |
| 28.8 kbps |
19 |
| 56.0 kbps |
44 |
| 64.0 kbps |
56 |
| 128.0 kbps |
105 |
- Choose the Audio codec. In order to figure out which codec to use. Follow this formula.
Video Bit Rate = (Total Bit Rate) - (Bandwidth of Audio Codec)
The RealVideo has discreet bandwidths. The video bit rate will be the difference between the total bit rate and the bit rate used by the chosen audio codec:
**Video Bit rate is calculated by the real video encoder automatically.
- Now choose the Frame Rate for the video. This depends on the content type of the video. If you have talking head type video The highest frame rate that can be achieved at 19 kbps, will be 7.5 to 10 frames per second (fps) for talking head type content with decent quality. A sporting event may only support 1 fps or maybe less. See the table below for a guidelines.
| Content type |
Target Bandwidth |
Total Bit Rate |
Audio Codec |
Audio Bit Rate |
Frame Rate |
| Talking Heads 28.8 |
28.8 |
19 |
6.5 Kbps voice |
6.5 |
optimize |
| Talking Heads 56 |
56.0 |
44 |
6.5 Kbps voice |
8.5 |
optimize |
Music Video
28.8, Emphasize Audio |
28.8 |
20 |
RealMedia 12 kbps |
12 |
.25 |
Music Video
56, Emphasize Audio |
56.0 |
44 |
RealAudio 3.0 - 28.8 Mono, full response |
16 |
optimize |
Music Video
28.8, Emphasize Video |
28.8 |
20 |
RealMedia 8 kbps |
8 |
optimize |
| Music Video 56, Emphasize Video |
56 |
44 |
RealMedia 12 kbps |
12 |
optimize |
| High Action w/ Voice, 28.8 |
28.8 |
19 |
6.5 Kbps voice |
6.5 |
1 |
| High Action w/ Voice, 56 |
56 |
44 |
RealAudio 2.0 - 28.8 |
15.2 |
optimize |
| High Action w/Music, 28.8 |
28.8 |
19 |
RealMedia 8 kbps |
8 |
1 |
| High Action w/ Music, 56 |
56 |
44 |
RealAudio 3.0 - 28.8 Mono, full response |
16 |
optimize |
| High Action, 56,Fractal |
56 |
44 |
RealAudio 3.0 - 28.8 Mono, full response |
8.5 |
10 |
| High Action, 112, Fractal |
112.0 |
44 |
RealAudio 3.0 - 28.8 Mono, full response |
8.5 |
10 |
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