Bit Rate Control
They are two philosophies when compressing a video stream:
- Constant bit rate (CBR): adapt automatically the video quality to keep the bit rate constant.
- Variable bit rate (VBR): keep the quality constant and allow the bit rate to vary.
Constant Bit Rate (CBR)
The user specifies the desired bit rate (in bits per second). The compression hardware tries to compress the video stream to achieve this bit rate.
Be aware that the effective bit rate depends on image content and amount of motion in the video. It is possible that the desired bit rate is never reached.
The CBR setting is available on Picolo Diligent with following output formats: MEDIASUBTYPE_DX50, WMMEDIASUBTYPE_MP4S.
Variable Bit Rate (VBR)
The user specifies the desired video quality (in percent). The compression hardware compresses the video stream and maintains the video quality. This leads to a variations of the bit rate depending on the amount of motion and the level of details in the video.
The VBR setting is available on Picolo Diligent with following output formats: MEDIASUBTYPE_DX50, WMMEDIASUBTYPE_MP4S.