The Tor Browser: media/libvpx/vp9/encoder/vp9_lookahead.c@b8a032363ba2 (annotated)

media/libvpx/vp9/encoder/vp9_lookahead.c@b8a032363ba2 (annotated)

media/libvpx/vp9/encoder/vp9_lookahead.c

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
  *  Copyright (c) 2011 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 <assert.h>
 #include <stdlib.h>
 #include "./vpx_config.h"
 #include "vp9/common/vp9_common.h"
 #include "vp9/encoder/vp9_lookahead.h"
 #include "vp9/common/vp9_extend.h"
 struct lookahead_ctx {
   unsigned int max_sz;         /* Absolute size of the queue */
   unsigned int sz;             /* Number of buffers currently in the queue */
   unsigned int read_idx;       /* Read index */
   unsigned int write_idx;      /* Write index */
   struct lookahead_entry *buf; /* Buffer list */
 };
 /* Return the buffer at the given absolute index and increment the index */
 static struct lookahead_entry * pop(struct lookahead_ctx *ctx,
                                     unsigned int *idx) {
   unsigned int index = *idx;
   struct lookahead_entry *buf = ctx->buf + index;
   assert(index < ctx->max_sz);
   if (++index >= ctx->max_sz)
     index -= ctx->max_sz;
   *idx = index;
   return buf;
 }
 void vp9_lookahead_destroy(struct lookahead_ctx *ctx) {
   if (ctx) {
     if (ctx->buf) {
       unsigned int i;
       for (i = 0; i < ctx->max_sz; i++)
         vp9_free_frame_buffer(&ctx->buf[i].img);
       free(ctx->buf);
     }
     free(ctx);
   }
 }
 struct lookahead_ctx * vp9_lookahead_init(unsigned int width,
                                           unsigned int height,
                                           unsigned int subsampling_x,
                                           unsigned int subsampling_y,
                                           unsigned int depth) {
   struct lookahead_ctx *ctx = NULL;
   // Clamp the lookahead queue depth
   depth = clamp(depth, 1, MAX_LAG_BUFFERS);
   // Allocate the lookahead structures
   ctx = calloc(1, sizeof(*ctx));
   if (ctx) {
     unsigned int i;
     ctx->max_sz = depth;
     ctx->buf = calloc(depth, sizeof(*ctx->buf));
     if (!ctx->buf)
       goto bail;
     for (i = 0; i < depth; i++)
       if (vp9_alloc_frame_buffer(&ctx->buf[i].img,
                                  width, height, subsampling_x, subsampling_y,
                                  VP9BORDERINPIXELS))
         goto bail;
   }
   return ctx;
  bail:
   vp9_lookahead_destroy(ctx);
   return NULL;
 }
 #define USE_PARTIAL_COPY 0
 int vp9_lookahead_push(struct lookahead_ctx *ctx, YV12_BUFFER_CONFIG   *src,
                        int64_t ts_start, int64_t ts_end, unsigned int flags,
                        unsigned char *active_map) {
   struct lookahead_entry *buf;
 #if USE_PARTIAL_COPY
   int row, col, active_end;
   int mb_rows = (src->y_height + 15) >> 4;
   int mb_cols = (src->y_width + 15) >> 4;
 #endif
   if (ctx->sz + 1 > ctx->max_sz)
     return 1;
   ctx->sz++;
   buf = pop(ctx, &ctx->write_idx);
 #if USE_PARTIAL_COPY
   // TODO(jkoleszar): This is disabled for now, as
   // vp9_copy_and_extend_frame_with_rect is not subsampling/alpha aware.
   // Only do this partial copy if the following conditions are all met:
   // 1. Lookahead queue has has size of 1.
   // 2. Active map is provided.
   // 3. This is not a key frame, golden nor altref frame.
   if (ctx->max_sz == 1 && active_map && !flags) {
     for (row = 0; row < mb_rows; ++row) {
       col = 0;
       while (1) {
         // Find the first active macroblock in this row.
         for (; col < mb_cols; ++col) {
           if (active_map[col])
             break;
         }
         // No more active macroblock in this row.
         if (col == mb_cols)
           break;
         // Find the end of active region in this row.
         active_end = col;
         for (; active_end < mb_cols; ++active_end) {
           if (!active_map[active_end])
             break;
         }
         // Only copy this active region.
         vp9_copy_and_extend_frame_with_rect(src, &buf->img,
                                             row << 4,
                                             col << 4, 16,
                                             (active_end - col) << 4);
         // Start again from the end of this active region.
         col = active_end;
       }
       active_map += mb_cols;
     }
   } else {
     vp9_copy_and_extend_frame(src, &buf->img);
   }
 #else
   // Partial copy not implemented yet
   vp9_copy_and_extend_frame(src, &buf->img);
 #endif
   buf->ts_start = ts_start;
   buf->ts_end = ts_end;
   buf->flags = flags;
   return 0;
 }
 struct lookahead_entry * vp9_lookahead_pop(struct lookahead_ctx *ctx,
                                            int drain) {
   struct lookahead_entry *buf = NULL;
   if (ctx->sz && (drain || ctx->sz == ctx->max_sz)) {
     buf = pop(ctx, &ctx->read_idx);
     ctx->sz--;
   }
   return buf;
 }
 struct lookahead_entry * vp9_lookahead_peek(struct lookahead_ctx *ctx,
                                             int index) {
   struct lookahead_entry *buf = NULL;
   assert(index < (int)ctx->max_sz);
   if (index < (int)ctx->sz) {
     index += ctx->read_idx;
     if (index >= (int)ctx->max_sz)
       index -= ctx->max_sz;
     buf = ctx->buf + index;
   }
   return buf;
 }
 unsigned int vp9_lookahead_depth(struct lookahead_ctx *ctx) {
   return ctx->sz;
 }

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media/libvpx/vp9/encoder/vp9_lookahead.c@b8a032363ba2 (annotated)

media/libvpx/vp9/encoder/vp9_lookahead.c