Race Technology Knowledge Base | ConfiguringTheVIDEO4 / RecordingQuality

Settings related to recording quality of VIDEO4

A. Bit-rate

This is the maximum possible number of bits that can be written to disk per second while recording. When the bit-rate is low, the video file is smaller, but the quality is reduced. If the bit-rate is high, the videos file get larger but the quality is improved. It is required to decide the bit-rate depending on the speed of the disk, disk size, required quality and time needs to record.

Video4 is capable to handle Bit-rates from 2 Mbps to 12 Mbps.

Bit-rate is required to set in the overlay file.

Typically:

2Mbps is fine for when the video is required for quick track side analysis with the data and used within the analysis

software. In this case load time of the video is more important than overall quality. When recording at this bit rate there are obvious "compression artifacts" around text, just as you get with a very compressed JPEG image.

4Mbps is considered the "normal" for video/data analysis with improved quality compared with 2Mbps. This setting is also adequate for generating DVD and subsequent playback on television.
6Mbps is consider the "normal" if the intention is to generate DVDs for playback on television. The DVD standard states that all players should support 6Mbps, although in practice most will support higher bit rates.
8Mbps can be used to generate very high quality DVDs although at this bitrate 100% compatibility cannot be garanteed.
9Mbps-12Mbps can be used to generate the highest quality video footage, however it is not recommended to generate DVDs at such high bitrates unless you previously tested you DVD player at these rates.

B. Video format

IMPORTANT: for nearly all applications it is recommended that this setting is left as the standard "IPB" setting.

There are three options to set for video format

I stand for Intra frames. I frames are large in size, but very very fast to decode and display

P stands for Predictive frame. These frames are about half size of I frame and take longer to display as we need to decode from the preceeding I frame and work forwards.

B stands for Bidirectional predictive frames. These frames are about quarter size of I frame, but take even longer to decode than a P frame as they more complex than a P frame in structure.

With option one, the VIDEO4 will only record video with Intra frames. This will result in reduced video quality compared to using P and B frames, but it will be faster in operation when using the analysis software.
With option two the VIDEO4 use a mixture of I and P frames (In the sequence of I PPPPPP I ….). The videos that are recorded with this setting will have good compression quality, and quite fast in operation.
The third option IPB is the optimal setting for VIDEO4. This is the DVD standard method for recording videos (The video will have a frame sequence I BB P BB P BB P…..). This is the best option for good quality video, but the decode speed will be reduced further.

Video format is required to set in the overlay file.