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// Copyright 2015 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 "vp8_decoder.h"
namespace media {
VP8Decoder::VP8Accelerator::VP8Accelerator() {}
VP8Decoder::VP8Accelerator::~VP8Accelerator() {}
VP8Decoder::VP8Decoder(VP8Accelerator* accelerator)
: state_(kNeedStreamMetadata),
curr_frame_start_(nullptr),
frame_size_(0),
accelerator_(accelerator) {
DCHECK(accelerator_);
}
VP8Decoder::~VP8Decoder() {}
bool VP8Decoder::Flush() {
DVLOG(2) << "Decoder flush";
Reset();
return true;
}
void VP8Decoder::SetStream(const uint8_t* ptr, size_t size) {
DCHECK(ptr);
DCHECK(size);
curr_frame_start_ = ptr;
frame_size_ = size;
DVLOG(4) << "New input stream at: " << (void*)ptr << " size: " << size;
}
void VP8Decoder::Reset() {
curr_pic_ = nullptr;
curr_frame_hdr_ = nullptr;
curr_frame_start_ = nullptr;
frame_size_ = 0;
last_frame_ = nullptr;
golden_frame_ = nullptr;
alt_frame_ = nullptr;
if (state_ == kDecoding)
state_ = kAfterReset;
}
VP8Decoder::DecodeResult VP8Decoder::Decode() {
if (!curr_frame_start_ || frame_size_ == 0)
return kRanOutOfStreamData;
if (!curr_frame_hdr_) {
curr_frame_hdr_.reset(new Vp8FrameHeader());
if (!parser_.ParseFrame(curr_frame_start_, frame_size_,
curr_frame_hdr_.get())) {
DVLOG(1) << "Error during decode";
state_ = kError;
return kDecodeError;
}
}
if (curr_frame_hdr_->IsKeyframe()) {
Size new_pic_size(curr_frame_hdr_->width, curr_frame_hdr_->height);
if (new_pic_size.IsEmpty())
return kDecodeError;
if (new_pic_size != pic_size_) {
DVLOG(2) << "New resolution: " << new_pic_size.ToString();
pic_size_ = new_pic_size;
DCHECK(!curr_pic_);
last_frame_ = nullptr;
golden_frame_ = nullptr;
alt_frame_ = nullptr;
return kAllocateNewSurfaces;
}
state_ = kDecoding;
} else {
if (state_ != kDecoding) {
// Need a resume point.
curr_frame_hdr_.reset();
return kRanOutOfStreamData;
}
}
curr_pic_ = accelerator_->CreateVP8Picture();
if (!curr_pic_)
return kRanOutOfSurfaces;
if (!DecodeAndOutputCurrentFrame())
return kDecodeError;
return kRanOutOfStreamData;
}
void VP8Decoder::RefreshReferenceFrames() {
if (curr_frame_hdr_->IsKeyframe()) {
last_frame_ = curr_pic_;
golden_frame_ = curr_pic_;
alt_frame_ = curr_pic_;
return;
}
// Save current golden since we overwrite it here,
// but may have to use it to update alt below.
scoped_refptr<VP8Picture> curr_golden = golden_frame_;
if (curr_frame_hdr_->refresh_golden_frame) {
golden_frame_ = curr_pic_;
} else {
switch (curr_frame_hdr_->copy_buffer_to_golden) {
case Vp8FrameHeader::COPY_LAST_TO_GOLDEN:
DCHECK(last_frame_);
golden_frame_ = last_frame_;
break;
case Vp8FrameHeader::COPY_ALT_TO_GOLDEN:
DCHECK(alt_frame_);
golden_frame_ = alt_frame_;
break;
}
}
if (curr_frame_hdr_->refresh_alternate_frame) {
alt_frame_ = curr_pic_;
} else {
switch (curr_frame_hdr_->copy_buffer_to_alternate) {
case Vp8FrameHeader::COPY_LAST_TO_ALT:
DCHECK(last_frame_);
alt_frame_ = last_frame_;
break;
case Vp8FrameHeader::COPY_GOLDEN_TO_ALT:
DCHECK(curr_golden);
alt_frame_ = curr_golden;
break;
}
}
if (curr_frame_hdr_->refresh_last)
last_frame_ = curr_pic_;
}
bool VP8Decoder::DecodeAndOutputCurrentFrame() {
DCHECK(!pic_size_.IsEmpty());
DCHECK(curr_pic_);
DCHECK(curr_frame_hdr_);
if (curr_frame_hdr_->IsKeyframe()) {
horizontal_scale_ = curr_frame_hdr_->horizontal_scale;
vertical_scale_ = curr_frame_hdr_->vertical_scale;
} else {
// Populate fields from decoder state instead.
curr_frame_hdr_->width = pic_size_.width();
curr_frame_hdr_->height = pic_size_.height();
curr_frame_hdr_->horizontal_scale = horizontal_scale_;
curr_frame_hdr_->vertical_scale = vertical_scale_;
}
if (!accelerator_->SubmitDecode(curr_pic_, curr_frame_hdr_.get(), last_frame_,
golden_frame_, alt_frame_))
return false;
if (curr_frame_hdr_->show_frame)
if (!accelerator_->OutputPicture(curr_pic_))
return false;
RefreshReferenceFrames();
curr_pic_ = nullptr;
curr_frame_hdr_ = nullptr;
curr_frame_start_ = nullptr;
frame_size_ = 0;
return true;
}
Size VP8Decoder::GetPicSize() const {
return pic_size_;
}
size_t VP8Decoder::GetRequiredNumOfPictures() const {
const size_t kVP8NumFramesActive = 4;
// TODO(johnylin): see if we could get rid of kMaxVideoFrames.
const size_t kMaxVideoFrames = 4;
const size_t kPicsInPipeline = kMaxVideoFrames + 2;
return kVP8NumFramesActive + kPicsInPipeline;
}
} // namespace media
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