User manual TERRATEC DIVX RECORDING

[. . . ] This is done in the Audio tab of the TerraTV software - usually the input port is called "Line In". Step 4: Recording setup Click on the gear or wrench on the upper left side of the TerraTV Software to open the configuration menu. Choose the "Record" tab and adjust the settings as shown below. [. . . ] This can be managed by the variable bitrate mode. In general, variable bitrate encoding requires more CPU power but offers better compression results. General Parameters This looks similar to the general setup of an MPEG codec, and seeing as DivX is basically a modified MPEG-4 codec, it makes sense. The most important setting is the Maximum Keyframe Interval. To explain this setting, we have to dig a bit deeper into MPEG compression technology. MPEG knows 3 basic image (frame) types (and some more advanced settings like motion vectors, but we will not examine them here). The first one is the I-Frame (Intra), which is simply a complete image. The second one is the P-Frame (Modifies Predicted Image), which contains only the information that can change the last I-Frame to a frame that would represent the next frame. This means { I-Frame 1 , I-Frame2 } (almost) equals { I-Frame 1, (I-Frame1 + P-Frame 1) }. Another one is the B-Frame (Bi-directional), which corresponds to the P-Frame, with the difference that it can also be related to the next frame. According to the encoded material the encoder uses a specific frame type sequence, the so called GOP (Group of Pictures). This GOP always begins with an I-Frame and has a specific duration (per default 300 frames). So the keyframe interval is the interval between two I-Frames, which represents the GOP-length. The higher the value, the higher the compression factor, with a negative effect on the quality. In other words: The lower the value, the more complex the scenes can become without causing visual artefacts on the compressed file. For example, cartoon movies can usually be compressed with a higher keyframe interval, action movies should have an interval equal to the default setting or lower. It would be possible, for example, to encode the daily news (without the video reports, just the newscaster) with just one I-Frame (Keyframe) and lots of P-Frames. The scene change threshold affects the automatic keyframing setting, which breaks and restarts the GOP when the scene changes are too complex for managing them with Pand B-Frames. [. . . ] You can end the recording anytime you want by pressing the Stop button or using the Escape key. The file that results from the recording is your new DivX compressed file. :) Useful Links To explore even more possibilities of recording with DivX, here are some links and programs that can help: 1. [. . . ]