Focus 3.2, Руководство пользователя

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Encoding Requirements and Recommendations
20
Encoding Recommendations
1. Resolution: 720 X 480 or 704 X 480 in NTSC; 704 X 576 in
PAL.
2. Closed GOP (Group of Pictures) with an “I-frame” every 15
frames is recommended.
3. The recommended audio bit rate is 384kbps and a sampling
rate of 48khz. It is recommended to play back test files using
the original source tapes to confirm audio levels
prior to
encoding an entire project. This will allow for calibration of
the encoding system to obtain a standard audio level.
4. Program stream files should have one end code (00 00 01 b9)
at the very end of the file. The Firefly can handle files without
end codes, but it is still a good idea to include one.
5. The bit rate can affect the size and transferability of the files.
The recommended bit rates for various types of video content
are as follows:
Table 1. Bit Rate Encoding Recommendations for Firefly
6. Although Firefly can transcode NTSC and PAL, it is
recommended to encode to the video standard (NTSC or PAL)
that you will be setting your Firefly to display.
Bit Rate Video Content
4 mbps Good quality with low motion
6 mbps Good quality with typical motion
8 mbps Good quality with high motion
10 mbps High quality with demanding content