extern "C"
{
#endif
+#include "vpx/vpx_codec.h"
#include "type_aliases.h"
#include "vpx_scale/yv12config.h"
#include "ppflags.h"
int max_bits;
// For CBR we need to also consider buffer fullness.
- // If we are running below the optimal level then we need to gradually tighten up on max_bits.
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER)
{
- double buffer_fullness_ratio = (double)cpi->buffer_level / DOUBLE_DIVIDE_CHECK((double)cpi->oxcf.optimal_buffer_level);
+ max_bits = 2 * cpi->av_per_frame_bandwidth;
+ max_bits -= cpi->estimated_display_frame_size;
+ max_bits *= ((double)cpi->oxcf.two_pass_vbrmax_section / 100.0);
+ }
+ // VBR
+ else
+ {
+ // For VBR base this on the bits and frames left plus the two_pass_vbrmax_section rate passed in by the user
+ max_bits = (int)(((double)cpi->twopass.bits_left / (cpi->twopass.total_stats->count - (double)cpi->common.current_video_frame)) * ((double)cpi->oxcf.two_pass_vbrmax_section / 100.0));
+ }
+
+ // Trap case where we are out of bits
+ if (max_bits < 0)
+ max_bits = 0;
- // For CBR base this on the target average bits per frame plus the maximum sedction rate passed in by the user
- max_bits = (int)(cpi->av_per_frame_bandwidth * ((double)cpi->oxcf.two_pass_vbrmax_section / 100.0));
+ return max_bits;
+}
- // If our buffer is below the optimum level
- if (buffer_fullness_ratio < 1.0)
- {
- // The lower of max_bits / 4 or cpi->av_per_frame_bandwidth / 4.
- int min_max_bits = ((cpi->av_per_frame_bandwidth >> 2) < (max_bits >> 2)) ? cpi->av_per_frame_bandwidth >> 2 : max_bits >> 2;
- max_bits = (int)(max_bits * buffer_fullness_ratio);
+static int gf_group_max_bits(VP8_COMP *cpi)
+{
+ // Max allocation for a golden frame group
+ int max_bits;
- if (max_bits < min_max_bits)
- max_bits = min_max_bits; // Lowest value we will set ... which should allow the buffer to refil.
+ // For CBR we need to also consider buffer fullness.
+ if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER)
+ {
+ max_bits = cpi->av_per_frame_bandwidth * cpi->baseline_gf_interval;
+ if (max_bits > cpi->oxcf.optimal_buffer_level)
+ {
+ max_bits -= cpi->oxcf.optimal_buffer_level;
+ max_bits += cpi->buffer_level;
}
+ else
+ {
+ max_bits -= (cpi->estimated_display_frame_size
+ - cpi->av_per_frame_bandwidth)
+ * cpi->baseline_gf_interval;
+ }
+
+ max_bits *= ((double)cpi->oxcf.two_pass_vbrmax_section / 100.0);
}
- // VBR
else
{
// For VBR base this on the bits and frames left plus the two_pass_vbrmax_section rate passed in by the user
max_bits = (int)(((double)cpi->twopass.bits_left / (cpi->twopass.total_stats->count - (double)cpi->common.current_video_frame)) * ((double)cpi->oxcf.two_pass_vbrmax_section / 100.0));
+ max_bits *= cpi->baseline_gf_interval;
}
+
// Trap case where we are out of bits
if (max_bits < 0)
max_bits = 0;
double abs_mv_in_out_accumulator = 0.0;
double mod_err_per_mb_accumulator = 0.0;
- int max_bits = frame_max_bits(cpi); // Max for a single frame
+ int max_group_bits;
unsigned int allow_alt_ref =
cpi->oxcf.play_alternate && cpi->oxcf.lag_in_frames;
// Clip cpi->twopass.gf_group_bits based on user supplied data rate
// variability limit (cpi->oxcf.two_pass_vbrmax_section)
- if (cpi->twopass.gf_group_bits > max_bits * cpi->baseline_gf_interval)
- cpi->twopass.gf_group_bits = max_bits * cpi->baseline_gf_interval;
+ max_group_bits = gf_group_max_bits(cpi);
+ if (cpi->twopass.gf_group_bits > max_group_bits)
+ cpi->twopass.gf_group_bits = max_group_bits;
// Reset the file position
reset_fpf_position(cpi, start_pos);
}
}
- // Apply an additional limit for CBR
- if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER)
- {
- if (cpi->twopass.gf_bits > (cpi->buffer_level >> 1))
- cpi->twopass.gf_bits = cpi->buffer_level >> 1;
- }
-
// Dont allow a negative value for gf_bits
if (gf_bits < 0)
gf_bits = 0;
cpi->rolling_actual_bits = cpi->av_per_frame_bandwidth;
cpi->long_rolling_target_bits = cpi->av_per_frame_bandwidth;
cpi->long_rolling_actual_bits = cpi->av_per_frame_bandwidth;
+ cpi->estimated_display_frame_size = cpi->av_per_frame_bandwidth;
cpi->total_actual_bits = 0;
cpi->total_target_vs_actual = 0;
break;
}
- if (cpi->pass == 0)
+ if (cpi->pass == 0 && cpi->oxcf.end_usage != USAGE_STREAM_FROM_SERVER)
cpi->auto_worst_q = 1;
cpi->oxcf.worst_allowed_q = q_trans[oxcf->worst_allowed_q];
}
+
+#define MIN(x,y) (((x)<(y))?(x):(y))
+static void update_buffer_levels(VP8_COMP *cpi)
+{
+ int max_network_xfer, actual_network_xfter;
+ int64_t tmp;
+
+ /* Model the size of the displayed frame at t-n.
+ *
+ * The decoder lags the encoder by the starting_buffer_level, so we
+ * calculate an average per-frame bitrate over that window.
+ *
+ * It is calculated accordingly:
+ *
+ * A = Average Bits Per Frame In The Buffer
+ * P = New Frame Size
+ * N = Number of bits in the buffer
+ * W = Weight of this frame
+ *
+ * We recalculate the average as so:
+ * (N-W)*A + W*P
+ * A' = -------------
+ * N
+ */
+ tmp = (cpi->oxcf.starting_buffer_level - cpi->av_per_frame_bandwidth)
+ * cpi->estimated_display_frame_size;
+ tmp += cpi->av_per_frame_bandwidth * cpi->projected_frame_size;
+ cpi->estimated_display_frame_size = tmp / cpi->oxcf.starting_buffer_level;
+
+
+ /* Update the network buffer model (leaky bucket) */
+ max_network_xfer = cpi->av_per_frame_bandwidth;
+ actual_network_xfter = MIN(max_network_xfer, cpi->network_buffer_level);
+ cpi->network_buffer_level += cpi->projected_frame_size;
+ cpi->network_buffer_level -= actual_network_xfter;
+
+ if(cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER)
+ {
+ /* In CBR mode, the rate at which the buffer is refilled is
+ * constrained by the network bandwidth and the actual number of
+ * bits that have previously been transmitted. This is modeling
+ * the live streaming case.
+ */
+
+ /* Update the client buffer model (leaky bucket) */
+ cpi->client_buffer_level += actual_network_xfter;
+ if (cpi->total_byte_count > cpi->oxcf.starting_buffer_level / 8)
+ cpi->client_buffer_level -= cpi->estimated_display_frame_size;
+
+ /* The control variable is the buffer on the client's side */
+ cpi->buffer_level = cpi->client_buffer_level;
+ }
+ else
+ {
+ /* In VBR mode, the available bandwidth is essentially unlimited
+ * so the buffer level can grow and be consumed without bound.
+ */
+ cpi->buffer_level = cpi->bits_off_target;
+ }
+}
+
+
static void encode_frame_to_data_rate
(
VP8_COMP *cpi,
// For CBR if the buffer reaches its maximum level then we can no longer
// save up bits for later frames so we might as well use them up
// on the current frame.
- if ((cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) &&
+ if (cpi->pass == 2
+ && (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) &&
(cpi->buffer_level >= cpi->oxcf.optimal_buffer_level) && cpi->buffered_mode)
{
int Adjustment = cpi->active_worst_quality / 4; // Max adjustment is 1/4
}
else
{
+ if(cpi->pass != 2)
+ Q = cpi->auto_worst_q?
+ cpi->active_worst_quality:cpi->avg_frame_qindex;
+
cpi->active_best_quality = inter_minq[Q];
// For the constant/constrained quality mode we dont want
(cpi->active_worst_quality < cpi->worst_quality) &&
(cpi->projected_frame_size > frame_over_shoot_limit))
{
- int over_size_percent = ((cpi->projected_frame_size - frame_over_shoot_limit) * 100) / frame_over_shoot_limit;
+ /* step down active_worst_quality such that the corresponding
+ * active_best_quality will be equal to the current
+ * active_worst_quality + 1. Once the limit on active_best_quality
+ * is reached, active_worst_quality will equal worst_quality.
+ */
+ int i;
- // If so is there any scope for relaxing it
- while ((cpi->active_worst_quality < cpi->worst_quality) && (over_size_percent > 0))
- {
- cpi->active_worst_quality++;
- top_index = cpi->active_worst_quality;
- over_size_percent = (int)(over_size_percent * 0.96); // Assume 1 qstep = about 4% on frame size.
- }
+ for(i=cpi->active_worst_quality; i<cpi->worst_quality; i++)
+ if(inter_minq[i] >= cpi->active_worst_quality + 1)
+ break;
+ cpi->active_worst_quality = i;
// If we have updated the active max Q do not call vp8_update_rate_correction_factors() this loop.
active_worst_qchanged = TRUE;
// Update the buffer level variable.
// Non-viewable frames are a special case and are treated as pure overhead.
- if ( !cm->show_frame )
- cpi->bits_off_target -= cpi->projected_frame_size;
- else
- cpi->bits_off_target += cpi->av_per_frame_bandwidth - cpi->projected_frame_size;
+ if ( cm->show_frame )
+ cpi->bits_off_target += cpi->av_per_frame_bandwidth;
+ cpi->bits_off_target -= cpi->projected_frame_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;
// Debug stats
cpi->total_target_vs_actual += (cpi->this_frame_target - cpi->projected_frame_size);
- cpi->buffer_level = cpi->bits_off_target;
+ update_buffer_levels(cpi);
// Update bits left to the kf and gf groups to account for overshoot or undershoot on these frames
if (cm->frame_type == KEY_FRAME)
int per_frame_bandwidth; // Current section per frame bandwidth target
int av_per_frame_bandwidth; // Average frame size target for clip
int min_frame_bandwidth; // Minimum allocation that should be used for any frame
+ int estimated_display_frame_size; // Recent average bitrate
+
int inter_frame_target;
double output_frame_rate;
int64_t last_time_stamp_seen;
int buffer_level;
int bits_off_target;
+ int network_buffer_level;
+ int client_buffer_level;
int rolling_target_bits;
int rolling_actual_bits;
int min_frame_target;
int Adjustment;
- min_frame_target = 0;
+ min_frame_target = 1;
if (cpi->pass == 2)
{
if (min_frame_target < (cpi->av_per_frame_bandwidth >> 5))
min_frame_target = cpi->av_per_frame_bandwidth >> 5;
}
- else if (min_frame_target < cpi->per_frame_bandwidth / 4)
- min_frame_target = cpi->per_frame_bandwidth / 4;
-
+ else
+ {
+ if (min_frame_target < cpi->per_frame_bandwidth / 4)
+ min_frame_target = cpi->per_frame_bandwidth / 4;
+ }
// Special alt reference frame case
if (cpi->common.refresh_alt_ref_frame)
// One Pass specific code
if (cpi->pass == 0)
{
+#if 1
+ int one_pct_bits, bits_off_optimum, pct_off_optimum;
+
+ one_pct_bits = 1 + cpi->oxcf.optimal_buffer_level / 100;
+ bits_off_optimum = cpi->buffer_level - cpi->oxcf.optimal_buffer_level;
+ pct_off_optimum = bits_off_optimum / one_pct_bits;
+
+ /* Clamp error to limit response agressiveness */
+ if (pct_off_optimum > cpi->oxcf.over_shoot_pct)
+ pct_off_optimum = cpi->oxcf.over_shoot_pct;
+ else if (pct_off_optimum < -cpi->oxcf.under_shoot_pct)
+ pct_off_optimum = -cpi->oxcf.under_shoot_pct;
+
+printf("%d\t%d\t%d\t",cpi->client_buffer_level, cpi->network_buffer_level, cpi->buffer_level);
+printf("%d\t%d\t%d\t",cpi->oxcf.optimal_buffer_level, bits_off_optimum, pct_off_optimum);
+printf("%d\t",cpi->this_frame_target);
+
+ if (cpi->network_buffer_level > cpi->estimated_display_frame_size)
+ {
+ /* Network buffer is full, the client buffer will be filled at
+ * the maximum rate. To increase the buffer level, we must reduce
+ * the average frame size. To decrease the buffer level, we must
+ * increase the recent bitrate.
+ */
+ pct_off_optimum *= -1;
+ }
+ else
+ {
+ /* Network buffer is empty. To increase the buffer level,
+ * we must send data faster than the network. To decrease the
+ * buffer level, we must send less than the recent bitrate.
+ */
+ cpi->this_frame_target = cpi->estimated_display_frame_size;
+ }
+
+ cpi->this_frame_target -= (cpi->this_frame_target * pct_off_optimum)
+ / 125;
+
+printf("%d\n",cpi->this_frame_target);
+
+
+ cpi->active_worst_quality = cpi->worst_quality;
+ // Worst quality obviously must not be better than best quality
+ if (cpi->active_worst_quality <= cpi->active_best_quality)
+ cpi->active_worst_quality = cpi->active_best_quality + 1;
+#else
// Adapt target frame size with respect to any buffering constraints:
if (cpi->buffered_mode)
{
{
cpi->active_worst_quality = cpi->cq_target_quality;
}
+#endif
}
// Test to see if we have to drop a frame
}
}
+
+#if 0
+ if (cpi->pass==0
+ && cpi->common.refresh_golden_frame
+ && cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
+ int64_t adjust;
+
+ /*
+ frames_in_buffer = cpi->oxcf.maximum_buffer_size
+ / cpi->av_per_frame_bandwidth;
+ gf_in_buffer = frames_in_buffer /
+ cpi->frames_till_gf_update_due;
+ overshoot_per_gf = cpi->accumulated_overshoot / gf_in_buffer;
+
+ */
+
+ adjust = cpi->accumulated_overshoot;
+ adjust *= cpi->frames_till_gf_update_due + 1;
+ adjust *= cpi->av_per_frame_bandwidth;
+ adjust /= cpi->oxcf.maximum_buffer_size;
+
+ if (adjust > (cpi->this_frame_target - min_frame_target))
+ adjust = (cpi->this_frame_target - min_frame_target);
+ else if (adjust < 0)
+ adjust = 0;
+
+ cpi->this_frame_target -= adjust;
+ }
+#endif
}
projects / libvpx / commitdiff