Add VAVDA, the VAAPI Video Decode Accelerator for Intel CPUs.

content/common/gpu/media/h264_dpb.cc

Index: content/common/gpu/media/h264_dpb.cc
diff --git a/content/common/gpu/media/h264_dpb.cc b/content/common/gpu/media/h264_dpb.cc
new file mode 100644
index 0000000000000000000000000000000000000000..1ed5010937494862241a4bc74f16f0f5b6d55647
--- /dev/null
+++ b/content/common/gpu/media/h264_dpb.cc
@@ -0,0 +1,142 @@
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "h264_dpb.h"
+
+#include <algorithm>
+
+#include "base/logging.h"
+#include "base/stl_util.h"
+
+namespace content {
+
+H264DPB::H264DPB() {}
+
+H264DPB::~H264DPB() {
+  Clear();
+}
+
+void H264DPB::Clear() {
+  STLDeleteElements(&pics_);
+}
+
+void H264DPB::RemovePic(const H264Picture::PtrVector::iterator iter) {
+  DVLOG(3) << "Removing pic_num: " << (*iter)->pic_num << " from DPB";
+  delete *iter;
+  pics_.erase(iter);
+}
+
+void H264DPB::RemoveByPOC(int poc) {
+  for (H264Picture::PtrVector::iterator it = pics_.begin(); it != pics_.end();
+      ++it) {
+    if ((*it)->pic_order_cnt == poc) {
+      RemovePic(it);
+      return;
+    }
+  }
+  DVLOG(1) << "Missing POC: " << poc;

[Ami GONE FROM CHROMIUM, 2012/04/09 02:41:47]

Is this not a DCHECK-able offense?

[Pawel Osciak, 2012/05/03 16:22:07]

Yeah, I'm reconsidering error resilience especially with what you've said about
not caring about malformed streams too much.

+}
+
+void H264DPB::RemoveUnused() {
+  for (H264Picture::PtrVector::iterator it = pics_.begin(); it != pics_.end();
+      ++it) {
+    if ((*it)->outputted && !(*it)->ref)
+      RemovePic(it);

[Ami GONE FROM CHROMIUM, 2012/04/09 02:41:47]

Isn't this a bug (erase inside RemovePic invalidates |it|).
I think you need to lose the ++it in the loop and instead
if (condition)
  RemovePic(it++);
else
  ++it;

[Pawel Osciak, 2012/05/03 16:22:07]

Of course. I always forget.

+  }
+}
+
+void H264DPB::StorePic(H264Picture* pic) {
+  DCHECK_LT(pics_.size(), kDPBMaxSize);
+  DVLOG(3) << "Adding PicNum: " << pic->pic_num << " ref: " << (int)pic->ref
+           << " longterm: " << (int)pic->long_term << " to DPB";
+  pics_.push_back(pic);
+}
+
+int H264DPB::CountRefPics() {
+  int ret = 0;
+  for (size_t i = 0; i < pics_.size(); ++i) {
+    if (pics_[i]->ref)
+      ++ret;
+  }
+  return ret;
+}
+
+void H264DPB::MarkAllUnusedForRef() {
+  for (size_t i = 0; i < pics_.size(); ++i)
+    pics_[i]->ref = false;
+}
+
+H264Picture* H264DPB::GetShortRefPicByPicNum(int pic_num) {
+  for (size_t i = 0; i < pics_.size(); ++i) {
+    H264Picture* pic = pics_[i];
+    if (pic->ref && !pic->long_term && pic->pic_num == pic_num)
+      return pic;
+  }
+
+  DVLOG(1) << "Missing short ref pic num: " << pic_num;

[Ami GONE FROM CHROMIUM, 2012/04/09 02:41:47]

Here and elsewhere aren't these properties of a malformed stream?
I ask b/c things like ShiftRightAndInsert DCHECK the non-NULLness of them.
DCHECK==programming invariant.  If it's invalid for these to return NULL why not
just CHECK here?
If a malformed stream can trigger a NULL return then callers must test for
NULLness and error out instead of crashing the process.

[Pawel Osciak, 2012/05/03 16:22:07]

My intention was to die gracefully with a stream error, but I failed to do that
in this case. Fixing.

+  return NULL;
+}
+
+H264Picture* H264DPB::GetLongRefPicByLongTermPicNum(int pic_num) {
+  for (size_t i = 0; i < pics_.size(); ++i) {
+    H264Picture* pic = pics_[i];
+    if (pic->ref && pic->long_term && pic->long_term_pic_num == pic_num)
+      return pic;
+  }
+
+  DVLOG(1) << "Missing long term pic num: " << pic_num;
+  return NULL;
+}
+
+H264Picture* H264DPB::GetLowestFrameNumWrapShortRefPic() {
+  H264Picture* ret = NULL;

[Ami GONE FROM CHROMIUM, 2012/04/09 02:41:47]

A trick to avoid the need for the !ret (and an extra set of parens below) is to
initialize ret to pics_[0], assuming you know pics_ is non-empty.

[Pawel Osciak, 2012/05/03 16:22:07]

Yeah, that's basically the case, but feel more comfortable keeping it this
way...

+  for (size_t i = 0; i < pics_.size(); ++i) {
+    H264Picture* pic = pics_[i];
+    if (pic->ref && !pic->long_term &&
+        (!ret || pic->frame_num_wrap < ret->frame_num_wrap))
+      ret = pic;
+  }
+  return ret;
+}
+
+struct IsH264PictureOutputted {
+  bool operator()(H264Picture*& pic) {
+    return pic->outputted;
+  }
+};
+
+void H264DPB::GetNotOutputtedPicsAppending(H264Picture::PtrVector& out) {
+  // Append to ret all not outputted pictures.
+  std::remove_copy_if(pics_.begin(), pics_.end(), std::back_inserter(out),
+                      IsH264PictureOutputted());

[Ami GONE FROM CHROMIUM, 2012/04/09 02:41:47]

Why algorithms instead of a loop?
(here and below).

[Pawel Osciak, 2012/05/03 16:22:07]

You really hate stl, don't you? ;)
Done, even without iterators, as you like it :)

[Ami GONE FROM CHROMIUM, 2012/05/03 23:22:53]

Hey, it's not just me - your editor (and future readers!) thank you as well.
Just look at the before/after of this code in 
https://chromiumcodereview.appspot.com/9814001/diff2/14001:23002/content/comm...
and tell me *you* don't prefer it algorithm-free, too!

+}
+
+struct IsH264PictureShortTermRef
+    : public std::unary_function<H264Picture*, bool> {
+  bool operator()(const H264Picture* pic) const {
+    return (pic->ref && !pic->long_term);
+  }
+};
+
+void H264DPB::GetShortTermRefPicsAppending(H264Picture::PtrVector& out) {
+  // copy_if in terms of remove_copy_if.
+  std::remove_copy_if(pics_.begin(), pics_.end(), std::back_inserter(out),
+                      std::not1(IsH264PictureShortTermRef()));
+}
+
+struct IsH264PictureLongTermRef
+    : public std::unary_function<H264Picture*, bool> {
+  bool operator()(const H264Picture* pic) const {
+    return (pic->ref && pic->long_term);
+  }
+};
+
+void H264DPB::GetLongTermRefPicsAppending(H264Picture::PtrVector& out) {
+  // copy_if in terms of remove_copy_if.
+  std::remove_copy_if(pics_.begin(), pics_.end(), std::back_inserter(out),
+                      std::not1(IsH264PictureLongTermRef()));
+}
+
+}  // namespace content
+