Clip buffer level to the maximum buffer size in CBR

The buffer level was able to increase indefinitely rather than
being clipped to the maximum buffer size specified by the user.

This change checks the buffrer level and prevents it from
going beyond the upper limit of the buffer.

Change-Id: Ifff55f79d3c018e4d3d77e554b11ada543cc1654
This commit is contained in:
Adrian Grange 2011-11-17 15:57:37 -08:00
parent 6dddcbc57d
commit eb15fe85e0
2 changed files with 14 additions and 0 deletions

View File

@ -3771,6 +3771,11 @@ static void encode_frame_to_data_rate
{
cpi->decimation_count --;
cpi->bits_off_target += cpi->av_per_frame_bandwidth;
// Clip the buffer level at the maximum buffer size
if (cpi->bits_off_target > cpi->oxcf.maximum_buffer_size)
cpi->bits_off_target = cpi->oxcf.maximum_buffer_size;
cm->current_video_frame++;
cpi->frames_since_key++;
@ -4614,6 +4619,10 @@ static void encode_frame_to_data_rate
else
cpi->bits_off_target += cpi->av_per_frame_bandwidth - cpi->projected_frame_size;
// Clip the buffer level at the maximum buffer size
if (cpi->bits_off_target > cpi->oxcf.maximum_buffer_size)
cpi->bits_off_target = cpi->oxcf.maximum_buffer_size;
// Rolling monitors of whether we are over or underspending used to help regulate min and Max Q in two pass.
cpi->rolling_target_bits = ((cpi->rolling_target_bits * 3) + cpi->this_frame_target + 2) / 4;
cpi->rolling_actual_bits = ((cpi->rolling_actual_bits * 3) + cpi->projected_frame_size + 2) / 4;

View File

@ -1028,6 +1028,11 @@ static void calc_pframe_target_size(VP8_COMP *cpi)
{
// Update the buffer level variable.
cpi->bits_off_target += cpi->av_per_frame_bandwidth;
// Clip the buffer level at the maximum buffer size
if (cpi->bits_off_target > cpi->oxcf.maximum_buffer_size)
cpi->bits_off_target = cpi->oxcf.maximum_buffer_size;
cpi->buffer_level = cpi->bits_off_target;
}
else