Hi, everyone<br> <br> In X264, I set a small value for vbv_bufsize and get a message "The VBV buffer size to samll, and <br>using xxx kbit". In the code, I find its default value is three times average frame size.
<br> h->param.rc.i_vbv_buffer_size = 3 * h->param.rc.i_vbv_max_bitrate / rc->fps;<br>can anyone suggest how to set the value for vbv_bufsize. I think the buffer at least should be able to cantain the<br>biggest frame that the encoder generates.
<br><br>The default vaue for vbv_buffer_init is 0.9. When I set vbv_buffer_init to 0, I find that the first I frame<br>gets a bigger QP than 0.9. In my opinion, when the vbv buffer contains less bits, Rate Control should give out
<br>a small QP to fill the buffer. <br><br> In Rate Control, vbv buffer is filled by <br>rct->buffer_fill_final += rct->buffer_rate - bits;<br> The bits exceeding the average frame size will accumulate in the VBV buffer. In video coding, I find the value is
<br>near the size of vbv buffer. VBV buffer is the input buffer of decoders. In anytime of video decoding, bitstream for<br>next frame should be feeded in input buffer, then decoders begin to decode the bitstream. If accumulating bits in vbv
<br>buffer is near its size, decoders can't put more bits in the input buffer. Am I right?<br><br>Thanks<br>Jogging