libvpx: Add VP9 decoder.

source/libvpx/vp9/encoder/vp9_picklpf.c

+/*
+ *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+
+#include "vp9/common/vp9_onyxc_int.h"
+#include "vp9/encoder/vp9_onyx_int.h"
+#include "vp9/encoder/vp9_picklpf.h"
+#include "vp9/encoder/vp9_quantize.h"
+#include "vpx_mem/vpx_mem.h"
+#include "vpx_scale/vpxscale.h"
+#include "vp9/common/vp9_alloccommon.h"
+#include "vp9/common/vp9_loopfilter.h"
+#include "./vpx_scale_rtcd.h"
+
+void vp9_yv12_copy_partial_frame_c(YV12_BUFFER_CONFIG *src_ybc,
+                                   YV12_BUFFER_CONFIG *dst_ybc, int Fraction) {
+  unsigned char *src_y, *dst_y;
+  int yheight;
+  int ystride;
+  int border;
+  int yoffset;
+  int linestocopy;
+
+  border   = src_ybc->border;
+  yheight  = src_ybc->y_height;
+  ystride  = src_ybc->y_stride;
+
+  linestocopy = (yheight >> (Fraction + 4));
+
+  if (linestocopy < 1)
+    linestocopy = 1;
+
+  linestocopy <<= 4;
+
+  yoffset  = ystride * ((yheight >> 5) * 16 - 8);
+  src_y = src_ybc->y_buffer + yoffset;
+  dst_y = dst_ybc->y_buffer + yoffset;
+
+  vpx_memcpy(dst_y, src_y, ystride * (linestocopy + 16));
+}
+
+static int calc_partial_ssl_err(YV12_BUFFER_CONFIG *source,
+                                YV12_BUFFER_CONFIG *dest, int Fraction) {
+  int i, j;
+  int Total = 0;
+  int srcoffset, dstoffset;
+  unsigned char *src = source->y_buffer;
+  unsigned char *dst = dest->y_buffer;
+
+  int linestocopy = (source->y_height >> (Fraction + 4));
+
+  if (linestocopy < 1)
+    linestocopy = 1;
+
+  linestocopy <<= 4;
+
+
+  srcoffset = source->y_stride   * (dest->y_height >> 5) * 16;
+  dstoffset = dest->y_stride     * (dest->y_height >> 5) * 16;
+
+  src += srcoffset;
+  dst += dstoffset;
+
+  // Loop through the Y plane raw and reconstruction data summing (square differences)
+  for (i = 0; i < linestocopy; i += 16) {
+    for (j = 0; j < source->y_width; j += 16) {
+      unsigned int sse;
+      Total += vp9_mse16x16(src + j, source->y_stride, dst + j, dest->y_stride,
+                            &sse);
+    }
+
+    src += 16 * source->y_stride;
+    dst += 16 * dest->y_stride;
+  }
+
+  return Total;
+}
+
+// Enforce a minimum filter level based upon baseline Q
+static int get_min_filter_level(VP9_COMP *cpi, int base_qindex) {
+  int min_filter_level;
+  /*int q = (int) vp9_convert_qindex_to_q(base_qindex);
+
+  if (cpi->source_alt_ref_active && cpi->common.refresh_golden_frame && !cpi->common.refresh_alt_ref_frame)
+      min_filter_level = 0;
+  else
+  {
+      if (q <= 10)
+          min_filter_level = 0;
+      else if (q <= 64)
+          min_filter_level = 1;
+      else
+          min_filter_level = (q >> 6);
+  }
+  */
+  min_filter_level = 0;
+
+  return min_filter_level;
+}
+
+// Enforce a maximum filter level based upon baseline Q
+static int get_max_filter_level(VP9_COMP *cpi, int base_qindex) {
+  // PGW August 2006: Highest filter values almost always a bad idea
+
+  // jbb chg: 20100118 - not so any more with this overquant stuff allow high values
+  // with lots of intra coming in.
+  int max_filter_level = MAX_LOOP_FILTER;// * 3 / 4;
+  (void)base_qindex;
+
+  if (cpi->twopass.section_intra_rating > 8)
+    max_filter_level = MAX_LOOP_FILTER * 3 / 4;
+
+  return max_filter_level;
+}
+
+void vp9_pick_filter_level_fast(YV12_BUFFER_CONFIG *sd, VP9_COMP *cpi) {
+  VP9_COMMON *cm = &cpi->common;
+
+  int best_err = 0;
+  int filt_err = 0;
+  int min_filter_level = get_min_filter_level(cpi, cm->base_qindex);
+  int max_filter_level = get_max_filter_level(cpi, cm->base_qindex);
+  int filt_val;
+  int best_filt_val = cm->filter_level;
+
+  //  Make a copy of the unfiltered / processed recon buffer
+  vp9_yv12_copy_partial_frame(cm->frame_to_show, &cpi->last_frame_uf, 3);
+
+  if (cm->frame_type == KEY_FRAME)
+    cm->sharpness_level = 0;
+  else
+    cm->sharpness_level = cpi->oxcf.Sharpness;
+
+  if (cm->sharpness_level != cm->last_sharpness_level) {
+    vp9_loop_filter_update_sharpness(&cm->lf_info, cm->sharpness_level);
+    cm->last_sharpness_level = cm->sharpness_level;
+  }
+
+  // Start the search at the previous frame filter level unless it is now out of range.
+  if (cm->filter_level < min_filter_level)
+    cm->filter_level = min_filter_level;
+  else if (cm->filter_level > max_filter_level)
+    cm->filter_level = max_filter_level;
+
+  filt_val = cm->filter_level;
+  best_filt_val = filt_val;
+
+  // Get the err using the previous frame's filter value.
+  vp9_loop_filter_partial_frame(cm, &cpi->mb.e_mbd, filt_val);
+
+  best_err = calc_partial_ssl_err(sd, cm->frame_to_show, 3);
+
+  //  Re-instate the unfiltered frame
+  vp9_yv12_copy_partial_frame(&cpi->last_frame_uf, cm->frame_to_show, 3);
+
+  filt_val -= (1 + ((filt_val > 10) ? 1 : 0));
+
+  // Search lower filter levels
+  while (filt_val >= min_filter_level) {
+    // Apply the loop filter
+    vp9_loop_filter_partial_frame(cm, &cpi->mb.e_mbd, filt_val);
+
+    // Get the err for filtered frame
+    filt_err = calc_partial_ssl_err(sd, cm->frame_to_show, 3);
+
+    //  Re-instate the unfiltered frame
+    vp9_yv12_copy_partial_frame(&cpi->last_frame_uf, cm->frame_to_show, 3);
+
+
+    // Update the best case record or exit loop.
+    if (filt_err < best_err) {
+      best_err = filt_err;
+      best_filt_val = filt_val;
+    } else
+      break;
+
+    // Adjust filter level
+    filt_val -= (1 + ((filt_val > 10) ? 1 : 0));
+  }
+
+  // Search up (note that we have already done filt_val = cm->filter_level)
+  filt_val = cm->filter_level + (1 + ((filt_val > 10) ? 1 : 0));
+
+  if (best_filt_val == cm->filter_level) {
+    // Resist raising filter level for very small gains
+    best_err -= (best_err >> 10);
+
+    while (filt_val < max_filter_level) {
+      // Apply the loop filter
+      vp9_loop_filter_partial_frame(cm, &cpi->mb.e_mbd, filt_val);
+
+      // Get the err for filtered frame
+      filt_err = calc_partial_ssl_err(sd, cm->frame_to_show, 3);
+
+      //  Re-instate the unfiltered frame
+      vp9_yv12_copy_partial_frame(&cpi->last_frame_uf,
+                                      cm->frame_to_show, 3);
+
+      // Update the best case record or exit loop.
+      if (filt_err < best_err) {
+        // Do not raise filter level if improvement is < 1 part in 4096
+        best_err = filt_err - (filt_err >> 10);
+
+        best_filt_val = filt_val;
+      } else
+        break;
+
+      // Adjust filter level
+      filt_val += (1 + ((filt_val > 10) ? 1 : 0));
+    }
+  }
+
+  cm->filter_level = best_filt_val;
+
+  if (cm->filter_level < min_filter_level)
+    cm->filter_level = min_filter_level;
+
+  if (cm->filter_level > max_filter_level)
+    cm->filter_level = max_filter_level;
+}
+
+// Stub function for now Alt LF not used
+void vp9_set_alt_lf_level(VP9_COMP *cpi, int filt_val) {
+}
+
+void vp9_pick_filter_level(YV12_BUFFER_CONFIG *sd, VP9_COMP *cpi) {
+  VP9_COMMON *cm = &cpi->common;
+
+  int best_err = 0;
+  int filt_err = 0;
+  int min_filter_level = get_min_filter_level(cpi, cm->base_qindex);
+  int max_filter_level = get_max_filter_level(cpi, cm->base_qindex);
+
+  int filter_step;
+  int filt_high = 0;
+  int filt_mid = cm->filter_level;      // Start search at previous frame filter level
+  int filt_low = 0;
+  int filt_best;
+  int filt_direction = 0;
+
+  int Bias = 0;                       // Bias against raising loop filter and in favour of lowering it
+
+  //  Make a copy of the unfiltered / processed recon buffer
+  vp8_yv12_copy_frame(cm->frame_to_show, &cpi->last_frame_uf);
+
+  if (cm->frame_type == KEY_FRAME)
+    cm->sharpness_level = 0;
+  else
+    cm->sharpness_level = cpi->oxcf.Sharpness;
+
+  // Start the search at the previous frame filter level unless it is now out of range.
+  filt_mid = cm->filter_level;
+
+  if (filt_mid < min_filter_level)
+    filt_mid = min_filter_level;
+  else if (filt_mid > max_filter_level)
+    filt_mid = max_filter_level;
+
+  // Define the initial step size
+  filter_step = (filt_mid < 16) ? 4 : filt_mid / 4;
+
+  // Get baseline error score
+  vp9_set_alt_lf_level(cpi, filt_mid);
+  vp9_loop_filter_frame_yonly(cm, &cpi->mb.e_mbd, filt_mid);
+
+  best_err = vp9_calc_ss_err(sd, cm->frame_to_show);
+  filt_best = filt_mid;
+
+  //  Re-instate the unfiltered frame
+  vp8_yv12_copy_y(&cpi->last_frame_uf, cm->frame_to_show);
+
+  while (filter_step > 0) {
+    Bias = (best_err >> (15 - (filt_mid / 8))) * filter_step; // PGW change 12/12/06 for small images
+
+    // jbb chg: 20100118 - in sections with lots of new material coming in don't bias as much to a low filter value
+    if (cpi->twopass.section_intra_rating < 20)
+      Bias = Bias * cpi->twopass.section_intra_rating / 20;
+
+    // yx, bias less for large block size
+    if (cpi->common.txfm_mode != ONLY_4X4)
+      Bias >>= 1;
+
+    filt_high = ((filt_mid + filter_step) > max_filter_level) ? max_filter_level : (filt_mid + filter_step);
+    filt_low = ((filt_mid - filter_step) < min_filter_level) ? min_filter_level : (filt_mid - filter_step);
+
+    if ((filt_direction <= 0) && (filt_low != filt_mid)) {
+      // Get Low filter error score
+      vp9_set_alt_lf_level(cpi, filt_low);
+      vp9_loop_filter_frame_yonly(cm, &cpi->mb.e_mbd, filt_low);
+
+      filt_err = vp9_calc_ss_err(sd, cm->frame_to_show);
+
+      //  Re-instate the unfiltered frame
+      vp8_yv12_copy_y(&cpi->last_frame_uf, cm->frame_to_show);
+
+      // If value is close to the best so far then bias towards a lower loop filter value.
+      if ((filt_err - Bias) < best_err) {
+        // Was it actually better than the previous best?
+        if (filt_err < best_err)
+          best_err = filt_err;
+
+        filt_best = filt_low;
+      }
+    }
+
+    // Now look at filt_high
+    if ((filt_direction >= 0) && (filt_high != filt_mid)) {
+      vp9_set_alt_lf_level(cpi, filt_high);
+      vp9_loop_filter_frame_yonly(cm, &cpi->mb.e_mbd, filt_high);
+
+      filt_err = vp9_calc_ss_err(sd, cm->frame_to_show);
+
+      //  Re-instate the unfiltered frame
+      vp8_yv12_copy_y(&cpi->last_frame_uf, cm->frame_to_show);
+
+      // Was it better than the previous best?
+      if (filt_err < (best_err - Bias)) {
+        best_err = filt_err;
+        filt_best = filt_high;
+      }
+    }
+
+    // Half the step distance if the best filter value was the same as last time
+    if (filt_best == filt_mid) {
+      filter_step = filter_step / 2;
+      filt_direction = 0;
+    } else {
+      filt_direction = (filt_best < filt_mid) ? -1 : 1;
+      filt_mid = filt_best;
+    }
+  }
+
+  cm->filter_level = filt_best;
+}