X3

MPEG-4 encoder settings
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Bit rate control
The bit rate indicates how much data per second is saved in the video
(playback speed). This makes the bit rate the deciding parameter for the
video to be encoded.
Mode
 Constant bit rate: The constant bit rate should only be used if the device
used to play the video supports constant bit rates.
 Constant quantizer:
 Variable bit rate: The bit rate varies. For faster movements in the video, the
bit rate increases, and for still images or slow pans, a lower bit rate is
sufficient for creating the video in constant quality.
Pass
 Single pass: The encoder process takes place without prior analysis. This
requires the least amount of time, however quality suffers.
 Multi-pass analysis: The first encoding is carried out at the same time as the
analysis for the second encoding is calculated.
 Multi-pass encode: The first encoding is carried out at the same time as the
analysis for the second encoding is calculated and updated. This produces
the best results, but the process requires the most time.
Bit rate (Bits/s)
 In "Constant bit rate" mode: Exactly those values entered are applied to be
able to calculate the size of the video precisely.
 In "Variable bit rate" mode: The values entered here are applied to the
video as an average as a guideline. The size of the video to be exported
can only be approximated.
HSS rate
This is the maximum bit rate that should be present in the video stream, i.e.
maximum number of bits that may be transferred to the decoder.
Note: This option is only available in "Variable bit rate" mode.
CPB size
This sets the size of the "coded picture buffer“ in bits. This is the buffer
where the encoding is carried out. The larger the buffer is, the better the
results will be, but the processing will also take much longer.
Aspect ratio
In the film industry, this is an indictation of the ratio between width and
height of a rectangle, monitor, or screen.