ref: 3a5b7dd08710be5331030a9defedbbaf9d346ca0
parent: 96f8895266e186f062e5837d0cb8275f5d6a775b
parent: 085f76e535a4376042d8eeadb1e4c5f246d74802
author: Yaowu Xu <[email protected]>
date: Mon Apr 21 05:11:19 EDT 2014
Merge "Add experimental VBR adaptation method."
--- a/vp9/encoder/vp9_firstpass.c
+++ b/vp9/encoder/vp9_firstpass.c
@@ -61,7 +61,7 @@
#define MIN_GF_INTERVAL 4
#endif
-#define DISABLE_RC_LONG_TERM_MEM
+#define LONG_TERM_VBR_CORRECTION
static void swap_yv12(YV12_BUFFER_CONFIG *a, YV12_BUFFER_CONFIG *b) {YV12_BUFFER_CONFIG temp = *a;
@@ -1033,6 +1033,9 @@
reset_fpf_position(twopass, start_pos);
}
+
+ // Reset the vbr bits off target counter
+ cpi->rc.vbr_bits_off_target = 0;
}
// This function gives an estimate of how badly we believe the prediction
@@ -2192,6 +2195,23 @@
cpi->rc.frames_to_key = INT_MAX;
}
+// For VBR...adjustment to the frame target based on error from previous frames
+void vbr_rate_correction(int * this_frame_target,
+ const int64_t vbr_bits_off_target) {+ int max_delta = *this_frame_target / 10;
+
+ // vbr_bits_off_target > 0 means we have extra bits to spend
+ if (vbr_bits_off_target > 0) {+ *this_frame_target +=
+ (vbr_bits_off_target > max_delta) ? max_delta
+ : (int)vbr_bits_off_target;
+ } else {+ *this_frame_target -=
+ (vbr_bits_off_target < -max_delta) ? max_delta
+ : (int)-vbr_bits_off_target;
+ }
+}
+
void vp9_rc_get_second_pass_params(VP9_COMP *cpi) {VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
@@ -2219,8 +2239,15 @@
return;
if (cpi->refresh_alt_ref_frame) {+ int modified_target = twopass->gf_bits;
+ rc->base_frame_target = twopass->gf_bits;
cm->frame_type = INTER_FRAME;
- vp9_rc_set_frame_target(cpi, twopass->gf_bits);
+#ifdef LONG_TERM_VBR_CORRECTION
+ // Correction to rate target based on prior over or under shoot.
+ if (cpi->oxcf.end_usage == USAGE_LOCAL_FILE_PLAYBACK)
+ vbr_rate_correction(&modified_target, rc->vbr_bits_off_target);
+#endif
+ vp9_rc_set_frame_target(cpi, modified_target);
return;
}
@@ -2315,6 +2342,13 @@
target = vp9_rc_clamp_iframe_target_size(cpi, rc->this_frame_target);
else
target = vp9_rc_clamp_pframe_target_size(cpi, rc->this_frame_target);
+
+ rc->base_frame_target = target;
+#ifdef LONG_TERM_VBR_CORRECTION
+ // Correction to rate target based on prior over or under shoot.
+ if (cpi->oxcf.end_usage == USAGE_LOCAL_FILE_PLAYBACK)
+ vbr_rate_correction(&target, rc->vbr_bits_off_target);
+#endif
vp9_rc_set_frame_target(cpi, target);
// Update the total stats remaining structure.
@@ -2322,20 +2356,38 @@
}
void vp9_twopass_postencode_update(VP9_COMP *cpi) {-#ifdef DISABLE_RC_LONG_TERM_MEM
- const uint64_t bits_used = cpi->rc.this_frame_target;
+ RATE_CONTROL *const rc = &cpi->rc;
+#ifdef LONG_TERM_VBR_CORRECTION
+ // In this experimental mode, the VBR correction is done exclusively through
+ // rc->vbr_bits_off_target. Based on the sign of this value, a limited %
+ // adjustment is made to the target rate of subsequent frames, to try and
+ // push it back towards 0. This mode is less likely to suffer from
+ // extreme behaviour at the end of a clip or group of frames.
+ const int bits_used = rc->base_frame_target;
+ rc->vbr_bits_off_target += rc->base_frame_target - rc->projected_frame_size;
#else
- const uint64_t bits_used = cpi->rc.projected_frame_size;
+ // In this mode, VBR correction is acheived by altering bits_left,
+ // kf_group_bits & gf_group_bits to reflect any deviation from the target
+ // rate in this frame. This alters the allocation of bits to the
+ // remaning frames in the group / clip.
+ // This method can give rise to unstable behaviour near the end of a clip
+ // or kf/gf group of frames where any accumulated error is corrected over an
+ // ever decreasing number of frames.
+ const int bits_used = rc->projected_frame_size;
#endif
+
cpi->twopass.bits_left -= bits_used;
cpi->twopass.bits_left = MAX(cpi->twopass.bits_left, 0);
- // Update bits left to the kf and gf groups to account for overshoot or
- // undershoot on these frames.
+
+#ifdef LONG_TERM_VBR_CORRECTION
+ if (cpi->common.frame_type != KEY_FRAME) {+#else
if (cpi->common.frame_type == KEY_FRAME) {// For key frames kf_group_bits already had the target bits subtracted out.
// So now update to the correct value based on the actual bits used.
cpi->twopass.kf_group_bits += cpi->rc.this_frame_target - bits_used;
} else {+#endif
cpi->twopass.kf_group_bits -= bits_used;
cpi->twopass.gf_group_bits -= bits_used;
cpi->twopass.gf_group_bits = MAX(cpi->twopass.gf_group_bits, 0);
--- a/vp9/encoder/vp9_onyx_if.c
+++ b/vp9/encoder/vp9_onyx_if.c
@@ -1745,8 +1745,8 @@
recon_err = vp9_get_y_sse(cpi->Source, get_frame_new_buffer(cm));
if (cpi->twopass.total_left_stats.coded_error != 0.0)
- fprintf(f, "%10u %10d %10d %10d %10d %10d "
- "%10"PRId64" %10"PRId64" %10d "
+ fprintf(f, "%10u %10d %10d %10d %10d"
+ "%10"PRId64" %10"PRId64" %10"PRId64" %10"PRId64" %10d "
"%7.2lf %7.2lf %7.2lf %7.2lf %7.2lf"
"%6d %6d %5d %5d %5d "
"%10"PRId64" %10.3lf"
@@ -1755,6 +1755,7 @@
cpi->rc.projected_frame_size,
cpi->rc.projected_frame_size / cpi->common.MBs,
(cpi->rc.projected_frame_size - cpi->rc.this_frame_target),
+ cpi->rc.vbr_bits_off_target,
cpi->rc.total_target_vs_actual,
(cpi->oxcf.starting_buffer_level - cpi->rc.bits_off_target),
cpi->rc.total_actual_bits, cm->base_qindex,
--- a/vp9/encoder/vp9_ratectrl.c
+++ b/vp9/encoder/vp9_ratectrl.c
@@ -1033,6 +1033,7 @@
RATE_CONTROL *const rc = &cpi->rc;
rc->this_frame_target = target;
+
// Target rate per SB64 (including partial SB64s.
rc->sb64_target_rate = ((int64_t)rc->this_frame_target * 64 * 64) /
(cm->width * cm->height);
--- a/vp9/encoder/vp9_ratectrl.h
+++ b/vp9/encoder/vp9_ratectrl.h
@@ -27,7 +27,9 @@
typedef struct {// Rate targetting variables
- int this_frame_target;
+ int base_frame_target; // A baseline frame target before adjustment
+ // for previous under or over shoot.
+ int this_frame_target; // Actual frame target after rc adjustment.
int projected_frame_size;
int sb64_target_rate;
int last_q[3]; // Separate values for Intra/Inter/ARF-GF
@@ -67,6 +69,7 @@
int64_t buffer_level;
int64_t bits_off_target;
+ int64_t vbr_bits_off_target;
int decimation_factor;
int decimation_count;