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Index: encoder/ratecontrol.c
===================================================================
--- encoder/ratecontrol.c (revision 680)
+++ encoder/ratecontrol.c (working copy)
@@ -43,6 +43,7 @@
int p_tex_bits;
int misc_bits;
uint64_t expected_bits;
+ double expected_vbv;
float new_qscale;
int new_qp;
int i_count;
@@ -1149,7 +1150,7 @@
return;
rct->buffer_fill_final += rct->buffer_rate - bits;
- if( rct->buffer_fill_final < 0 && !rct->b_2pass )
+ if( rct->buffer_fill_final < 0 )
x264_log( h, X264_LOG_WARNING, "VBV underflow (%.0f bits)\n", rct->buffer_fill_final );
rct->buffer_fill_final = x264_clip3f( rct->buffer_fill_final, 0, rct->buffer_size );
}
@@ -1325,6 +1326,28 @@
double w = x264_clip3f( time*100, 0.0, 1.0 );
q *= pow( (double)total_bits / rcc->expected_bits_sum, w );
}
+ if( rcc->b_vbv )
+ {
+ double expected_size = qscale2bits(&rce, q);
+ double expected_vbv = rcc->buffer_fill + rcc->buffer_rate - expected_size;
+ if( (expected_vbv < rcc->buffer_size*.4) && (expected_vbv < rce.expected_vbv) )
+ {
+ double qmax = (expected_vbv < rcc->buffer_size*.15) ? lmax : q*1.5;
+ double size_constraint = 1 + rce.expected_vbv/rcc->buffer_size;
+ while( (expected_vbv < rce.expected_vbv/size_constraint) && (q < qmax) )
+ {
+ q *= 1.05;
+ expected_size = qscale2bits(&rce, q);
+ expected_vbv = rcc->buffer_fill + rcc->buffer_rate - expected_size;
+ }
+/* x264_log( h, X264_LOG_INFO,
+ "frame %d rcc expected vbv = %d encoding expected vbv = %d\n",
+ (int)(h->fenc->i_frame),
+ (int)(rce.expected_vbv),
+ (int)(expected_vbv));*/
+
+ }
+ }
q = x264_clip3f( q, lmin, lmax );
}
else /* 1pass ABR */
@@ -1455,6 +1478,137 @@
/* the rest of the variables are either constant or thread-local */
}
+FILE *fh_vbv;
+
+static int find_underflow( x264_t *h, double *fills, int *t0, int *t1, int over )
+{
+ /* find an interval ending on an overflow or underflow (depending on whether
+ * we're adding or removing bits), and starting on the earliest frame that
+ * can influence the buffer fill of that end frame. */
+ x264_ratecontrol_t *rcc = h->rc;
+ const double buffer_min = (over ? .1 : .1) * rcc->buffer_size;
+ const double buffer_max = .9 * rcc->buffer_size;
+ double fill = fills[*t0-1];
+ double parity = over ? 1. : -1.;
+ int i, start=-1, end=-1;
+ for(i=*t0; i<rcc->num_entries; i++)
+ {
+ fill += (rcc->buffer_rate - qscale2bits(&rcc->entry[i], rcc->entry[i].new_qscale)) * parity;
+ fill = x264_clip3f(fill, 0, rcc->buffer_size);
+ fills[i] = fill;
+ if(fill <= buffer_min || i == 0)
+ {
+ if(end >= 0)
+ break;
+ start = i;
+ }
+ else if(fill >= buffer_max && start >= 0)
+ end = i;
+ }
+ *t0 = start;
+ *t1 = end;
+ return start>=0 && end>=0;
+}
+
+static void fix_underflow( x264_t *h, int t0, int t1, double adjustment )
+{
+ x264_ratecontrol_t *rcc = h->rc;
+ int i;
+ if(t0 > 0)
+ t0++;
+// printf("interval [%d,%d] %.4f\n", t0, t1, adjustment);
+ for(i=t0; i<=t1; i++)
+ rcc->entry[i].new_qscale *= adjustment;
+}
+
+static double count_expected_bits( x264_t *h )
+{
+ x264_ratecontrol_t *rcc = h->rc;
+ double expected_bits = 0;
+ int i;
+ for(i=0; i<rcc->num_entries; i++)
+ {
+ ratecontrol_entry_t *rce = &rcc->entry[i];
+ rce->expected_bits = expected_bits;
+ expected_bits += qscale2bits(rce, rce->new_qscale);
+ }
+ return expected_bits;
+}
+
+static void debug_dump_vbv( x264_t *h )
+{
+ x264_ratecontrol_t *rcc = h->rc;
+ double fill = rcc->buffer_size * h->param.rc.f_vbv_buffer_init;
+ int i;
+ for(i=0; i<rcc->num_entries; i++)
+ {
+ fill += rcc->buffer_rate - qscale2bits(&rcc->entry[i], rcc->entry[i].new_qscale);
+ fill = x264_clip3f(fill, rcc->buffer_size*-.5, rcc->buffer_size);
+ fprintf(fh_vbv, "%d %.0f\n", i, fill);
+ }
+}
+
+static void vbv_pass2( x264_t *h )
+{
+ /* foreach interval of buffer_full .. underflow
+ * uniformly increase the qp of all frames in the interval until either
+ * buffer is full at some intermediate frame
+ * or the last frame in the interval no longer underflows
+ * recompute intervals and repeat
+ * then do the converse to put bits back into overflow areas until target size is met */
+
+ x264_ratecontrol_t *rcc = h->rc;
+ double *fills = x264_malloc((rcc->num_entries+1)*sizeof(double));
+ double all_available_bits = h->param.rc.i_bitrate * 1000. * rcc->num_entries / rcc->fps;
+ double expected_bits, prev_bits, adjustment;
+ int i, t0, t1, space;
+
+ fills++;
+// fh_vbv = fopen("vbv.log", "w");
+
+ //adjust overall stream size
+ do {
+ space = 0;
+
+ fills[-1] = rcc->buffer_size * (1. - h->param.rc.f_vbv_buffer_init);
+ t0 = 0;
+ //fix underflows
+ while(find_underflow(h, fills, &t0, &t1, 0))
+ {
+ fix_underflow(h, t0, t1, 1.001);
+ space = 1;
+ }
+
+ prev_bits = expected_bits = count_expected_bits(h);
+ adjustment = X264_MAX(expected_bits / all_available_bits, 0.999);
+ fills[-1] = rcc->buffer_size * h->param.rc.f_vbv_buffer_init;
+ t0 = 0;
+ //fix overflows
+ while(find_underflow(h, fills, &t0, &t1, 1))
+ {
+ fix_underflow(h, t0, t1, adjustment);
+ t0 = t1;
+ space = 1;
+ }
+ expected_bits = count_expected_bits(h);
+ } while(space && expected_bits < .995*all_available_bits && expected_bits >= prev_bits+1);
+
+ //better undersizing target than underflowing vbv
+ fills[-1] = rcc->buffer_size * (1. - h->param.rc.f_vbv_buffer_init);
+ t0 = 0;
+ while(find_underflow(h, fills, &t0, &t1, 0))
+ fix_underflow(h, t0, t1, 1.001);
+
+// debug_dump_vbv(h);
+
+ //store expected vbv filling values for tracking when encoding
+ for(i=0; i<rcc->num_entries; i++)
+ rcc->entry[i].expected_vbv = rcc->buffer_size - fills[i];
+
+// fclose(fh_vbv);
+ x264_free(fills-1);
+}
+
static int init_pass2( x264_t *h )
{
x264_ratecontrol_t *rcc = h->rc;
@@ -1543,7 +1697,6 @@
rcc->last_non_b_pict_type = -1;
rcc->last_accum_p_norm = 1;
rcc->accum_p_norm = 0;
- rcc->buffer_fill = rcc->buffer_size * h->param.rc.f_vbv_buffer_init;
/* find qscale */
for(i=0; i<rcc->num_entries; i++){
@@ -1580,15 +1733,9 @@
/* find expected bits */
for(i=0; i<rcc->num_entries; i++){
ratecontrol_entry_t *rce = &rcc->entry[i];
- double bits;
rce->new_qscale = clip_qscale(h, rce->pict_type, blurred_qscale[i]);
assert(rce->new_qscale >= 0);
- bits = qscale2bits(rce, rce->new_qscale);
-
- rce->expected_bits = expected_bits;
- expected_bits += bits;
- update_vbv(h, bits);
- rcc->buffer_fill = rcc->buffer_fill_final;
+ expected_bits += qscale2bits(rce, rce->new_qscale);
}
//printf("expected:%llu available:%llu factor:%lf avgQ:%lf\n", (uint64_t)expected_bits, all_available_bits, rate_factor);
@@ -1599,6 +1746,10 @@
if(filter_size > 1)
x264_free(blurred_qscale);
+ if(rcc->b_vbv)
+ vbv_pass2(h);
+ expected_bits = count_expected_bits(h);
+
if(fabs(expected_bits/all_available_bits - 1.0) > 0.01)
{
double avgq = 0;
@@ -1606,7 +1757,8 @@
avgq += rcc->entry[i].new_qscale;
avgq = qscale2qp(avgq / rcc->num_entries);
- x264_log(h, X264_LOG_WARNING, "Error: 2pass curve failed to converge\n");
+ if ((expected_bits > all_available_bits) || (!rcc->b_vbv))
+ x264_log(h, X264_LOG_WARNING, "Error: 2pass curve failed to converge\n");
x264_log(h, X264_LOG_WARNING, "target: %.2f kbit/s, expected: %.2f kbit/s, avg QP: %.4f\n",
(float)h->param.rc.i_bitrate,
expected_bits * rcc->fps / (rcc->num_entries * 1000.),
@@ -1625,7 +1777,7 @@
else
x264_log(h, X264_LOG_WARNING, "try increasing target bitrate\n");
}
- else
+ else if(!(rcc->b_2pass && rcc->b_vbv))
x264_log(h, X264_LOG_WARNING, "internal error\n");
}
@@ -1633,3 +1785,4 @@
}
+
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