}
-static void calc_iframe_target_size(VP8_COMP *cpi);
+static int estimate_bits_at_q(int frame_kind, int Q, int MBs,
+ double correction_factor)
+{
+ int Bpm = (int)(.5 + correction_factor * vp8_bits_per_mb[frame_kind][Q]);
+
+ /* Attempt to retain reasonable accuracy without overflow. The cutoff is
+ * chosen such that the maximum product of Bpm and MBs fits 31 bits. The
+ * largest Bpm takes 20 bits.
+ */
+ if (MBs > (1 << 11))
+ return (Bpm >> BPER_MB_NORMBITS) * MBs;
+ else
+ return (Bpm * MBs) >> BPER_MB_NORMBITS;
+}
-static void calc_auto_iframe_target_size(VP8_COMP *cpi)
+static void calc_iframe_target_size(VP8_COMP *cpi)
{
// boost defaults to half second
int kf_boost;
+ int target;
// Clear down mmx registers to allow floating point in what follows
vp8_clear_system_state(); //__asm emms;
if (cpi->oxcf.fixed_q >= 0)
{
- calc_iframe_target_size(cpi);
- return;
- }
+ int Q = cpi->oxcf.key_q;
- if (cpi->pass == 2)
+ target = estimate_bits_at_q(INTRA_FRAME, Q, cpi->common.MBs,
+ cpi->key_frame_rate_correction_factor);
+ }
+ else if (cpi->pass == 2)
{
- cpi->this_frame_target = cpi->per_frame_bandwidth; // New Two pass RC
+ // New Two pass RC
+ target = cpi->per_frame_bandwidth;
+ }
+ // First Frame is a special case
+ else if (cpi->common.current_video_frame == 0)
+ {
+ /* 1 Pass there is no information on which to base size so use
+ * bandwidth per second * fraction of the initial buffer
+ * level
+ */
+ target = cpi->oxcf.starting_buffer_level / 2;
+
+ if(target > cpi->oxcf.target_bandwidth * 3 / 2)
+ target = cpi->oxcf.target_bandwidth * 3 / 2;
}
else
{
+ // if this keyframe was forced, use a more recent Q estimate
+ int Q = (cpi->common.frame_flags & FRAMEFLAGS_KEY)
+ ? cpi->avg_frame_qindex : cpi->ni_av_qi;
+
// Boost depends somewhat on frame rate
kf_boost = (int)(2 * cpi->output_frame_rate - 16);
// adjustment up based on q
- kf_boost = kf_boost * kf_boost_qadjustment[cpi->ni_av_qi] / 100;
+ kf_boost = kf_boost * kf_boost_qadjustment[Q] / 100;
// frame separation adjustment ( down)
if (cpi->frames_since_key < cpi->output_frame_rate / 2)
- kf_boost = (int)(kf_boost * cpi->frames_since_key / (cpi->output_frame_rate / 2));
+ kf_boost = (int)(kf_boost
+ * cpi->frames_since_key / (cpi->output_frame_rate / 2));
if (kf_boost < 16)
kf_boost = 16;
- // Reset the active worst quality to the baseline value for key frames.
- cpi->active_worst_quality = cpi->worst_quality;
-
- cpi->this_frame_target = ((16 + kf_boost) * cpi->per_frame_bandwidth) >> 4;
+ target = ((16 + kf_boost) * cpi->per_frame_bandwidth) >> 4;
}
- // Should the next frame be an altref frame
- if (cpi->pass != 2)
+ if (cpi->oxcf.rc_max_intra_bitrate_pct)
{
- // For now Alt ref is not allowed except in 2 pass modes.
- cpi->source_alt_ref_pending = FALSE;
+ unsigned int max_rate = cpi->per_frame_bandwidth
+ * cpi->oxcf.rc_max_intra_bitrate_pct / 100;
- /*if ( cpi->oxcf.fixed_q == -1)
- {
- if ( cpi->oxcf.play_alternate && ( (cpi->last_boost/2) > (100+(AF_THRESH*cpi->frames_till_gf_update_due)) ) )
- cpi->source_alt_ref_pending = TRUE;
- else
- cpi->source_alt_ref_pending = FALSE;
- }*/
+ if (target > max_rate)
+ target = max_rate;
}
- if (0)
+ cpi->this_frame_target = target;
+
+ // TODO: if we separate rate targeting from Q targetting, move this.
+ // Reset the active worst quality to the baseline value for key frames.
+ cpi->active_worst_quality = cpi->worst_quality;
+
+#if 0
{
FILE *f;
fclose(f);
}
+#endif
}
+
// Do the best we can to define the parameteres for the next GF based on what information we have available.
static void calc_gf_params(VP8_COMP *cpi)
{
}*/
}
}
-/* This is equvialent to estimate_bits_at_q without the rate_correction_factor. */
-static int baseline_bits_at_q(int frame_kind, int Q, int MBs)
-{
- int Bpm = vp8_bits_per_mb[frame_kind][Q];
-
- /* Attempt to retain reasonable accuracy without overflow. The cutoff is
- * chosen such that the maximum product of Bpm and MBs fits 31 bits. The
- * largest Bpm takes 20 bits.
- */
- if (MBs > (1 << 11))
- return (Bpm >> BPER_MB_NORMBITS) * MBs;
- else
- return (Bpm * MBs) >> BPER_MB_NORMBITS;
-}
-
-
-static void calc_iframe_target_size(VP8_COMP *cpi)
-{
- int Q;
- int Boost = 100;
-
- Q = (cpi->oxcf.fixed_q >= 0) ? cpi->oxcf.fixed_q : cpi->avg_frame_qindex;
-
- if (cpi->auto_adjust_key_quantizer == 1)
- {
- // If (auto_adjust_key_quantizer==1) then a lower Q is selected for key-frames.
- // The enhanced Q is calculated so as to boost the key frame size by a factor
- // specified in kf_boost_qadjustment. Also, can adjust based on distance
- // between key frames.
-
- // Adjust boost based upon ambient Q
- Boost = kf_boost_qadjustment[Q];
-
- // Make the Key frame boost less if the seperation from the previous key frame is small
- if (cpi->frames_since_key < 16)
- Boost = Boost * kf_boost_seperation_adjustment[cpi->frames_since_key] / 100;
- else
- Boost = Boost * kf_boost_seperation_adjustment[15] / 100;
-
- // Apply limits on boost
- if (Boost > kf_gf_boost_qlimits[Q])
- Boost = kf_gf_boost_qlimits[Q];
- else if (Boost < 120)
- Boost = 120;
- }
-
- // Keep a record of the boost that was used
- cpi->last_boost = Boost;
-
- // Should the next frame be an altref frame
- if (cpi->pass != 2)
- {
- // For now Alt ref is not allowed except in 2 pass modes.
- cpi->source_alt_ref_pending = FALSE;
-
- /*if ( cpi->oxcf.fixed_q == -1)
- {
- if ( cpi->oxcf.play_alternate && ( (cpi->last_boost/2) > (100+(AF_THRESH*cpi->frames_till_gf_update_due)) ) )
- cpi->source_alt_ref_pending = TRUE;
- else
- cpi->source_alt_ref_pending = FALSE;
- }*/
- }
-
- if (cpi->oxcf.fixed_q >= 0)
- {
- cpi->this_frame_target = (baseline_bits_at_q(0, Q, cpi->common.MBs) * Boost) / 100;
- }
- else
- {
-
- int bits_per_mb_at_this_q ;
-
- if (cpi->oxcf.error_resilient_mode == 1)
- {
- cpi->this_frame_target = 2 * cpi->av_per_frame_bandwidth;
- return;
- }
-
- // Rate targetted scenario:
- // Be careful of 32-bit OVERFLOW if restructuring the caluclation of cpi->this_frame_target
- bits_per_mb_at_this_q = (int)(.5 +
- cpi->key_frame_rate_correction_factor * vp8_bits_per_mb[0][Q]);
-
- cpi->this_frame_target = (((bits_per_mb_at_this_q * cpi->common.MBs) >> BPER_MB_NORMBITS) * Boost) / 100;
-
- // Reset the active worst quality to the baseline value for key frames.
- if (cpi->pass < 2)
- cpi->active_worst_quality = cpi->worst_quality;
- }
-}
static void calc_pframe_target_size(VP8_COMP *cpi)
}
}
else
- cpi->this_frame_target = (baseline_bits_at_q(1, Q, cpi->common.MBs) * cpi->last_boost) / 100;
+ cpi->this_frame_target =
+ (estimate_bits_at_q(1, Q, cpi->common.MBs, 1.0)
+ * cpi->last_boost) / 100;
}
// If there is an active ARF at this location use the minimum
}
}
-static int estimate_bits_at_q(VP8_COMP *cpi, int Q)
-{
- int Bpm = (int)(.5 + cpi->rate_correction_factor * vp8_bits_per_mb[INTER_FRAME][Q]);
-
- /* Attempt to retain reasonable accuracy without overflow. The cutoff is
- * chosen such that the maximum product of Bpm and MBs fits 31 bits. The
- * largest Bpm takes 20 bits.
- */
- if (cpi->common.MBs > (1 << 11))
- return (Bpm >> BPER_MB_NORMBITS) * cpi->common.MBs;
- else
- return (Bpm * cpi->common.MBs) >> BPER_MB_NORMBITS;
-
-}
-
int vp8_regulate_q(VP8_COMP *cpi, int target_bits_per_frame)
{
{
VP8_COMMON *cm = &cpi->common;
- // First Frame is a special case
- if (cm->current_video_frame == 0)
- {
-#if !(CONFIG_REALTIME_ONLY)
-
- if (cpi->pass == 2)
- calc_auto_iframe_target_size(cpi);
-
- else
-#endif
- {
- /* 1 Pass there is no information on which to base size so use
- * bandwidth per second * fraction of the initial buffer
- * level
- */
- cpi->this_frame_target = cpi->oxcf.starting_buffer_level / 2;
-
- if(cpi->this_frame_target > cpi->oxcf.target_bandwidth * 3 / 2)
- cpi->this_frame_target = cpi->oxcf.target_bandwidth * 3 / 2;
- }
-
- // Key frame from VFW/auto-keyframe/first frame
- cm->frame_type = KEY_FRAME;
-
- }
- // Special case for forced key frames
- // The frame sizing here is still far from ideal for 2 pass.
- else if (cm->frame_flags & FRAMEFLAGS_KEY)
- {
+ if (cm->frame_type == KEY_FRAME)
calc_iframe_target_size(cpi);
- }
- else if (cm->frame_type == KEY_FRAME)
- {
- calc_auto_iframe_target_size(cpi);
- }
else
{
- // INTER frame: compute target frame size
- cm->frame_type = INTER_FRAME;
calc_pframe_target_size(cpi);
// Check if we're dropping the frame:
return 0;
}
}
-
- /* Apply limits on keyframe target.
- *
- * TODO: move this after consolidating
- * calc_iframe_target_size() and calc_auto_iframe_target_size()
- */
- if (cm->frame_type == KEY_FRAME && cpi->oxcf.rc_max_intra_bitrate_pct)
- {
- unsigned int max_rate = cpi->av_per_frame_bandwidth
- * cpi->oxcf.rc_max_intra_bitrate_pct / 100;
-
- if (cpi->this_frame_target > max_rate)
- cpi->this_frame_target = max_rate;
- }
return 1;
}