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<p class="MsoNormal">Hi All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m working on an application where we need to make an accurate as possible prediction of what the output frame size will be in VBV single frame encoding mode.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Currently I’m seeing a lot of fluctuation in the actual output frame size compared to what I’ve set the target frame size too using bitrate and vbv_max_bitrate and vbv_buffer_size, anywhere from 5-50%+ is required to be padded in the buffer.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I understand that this is expected at some level and *<b>some</b>* overhead is required to avoid overflow, but is there anything that can be done to predictably force the encoder to use more bytes available to it up to the max_bitrate?
Also, is it expected that the encoder could be out by as much as 50% of more on the target size?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The reason being the application of the encoding is with an aim to save network bytes vs. video quality – need to make use of as many bytes as possible rather than adding this waste padding post-encoding. I’ve an example of what’s being
output from the encoder here in annexb format if anyone wants a look - <a href="https://www.fileconvoy.com/dfl.php?id=g781609c1931ef8509994117496219f4e1154c6ece">
https://www.fileconvoy.com/dfl.php?id=g781609c1931ef8509994117496219f4e1154c6ece</a><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advance,<o:p></o:p></p>
<p class="MsoNormal">Paul McDermott<o:p></o:p></p>
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