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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 "media/cast/sender/external_video_encoder.h"
#include <stdint.h>
#include "media/base/video_frame.h"
#include "media/base/video_types.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace media {
namespace cast {
namespace {
scoped_refptr<VideoFrame> CreateFrame(const uint8_t* y_plane_data,
const gfx::Size& size) {
scoped_refptr<VideoFrame> result = VideoFrame::CreateFrame(PIXEL_FORMAT_I420,
size,
gfx::Rect(size),
size,
base::TimeDelta());
for (int y = 0, y_end = size.height(); y < y_end; ++y) {
memcpy(result->visible_data(VideoFrame::kYPlane) +
y * result->stride(VideoFrame::kYPlane),
y_plane_data + y * size.width(),
size.width());
}
return result;
}
} // namespace
TEST(QuantizerEstimator, EstimatesForTrivialFrames) {
QuantizerEstimator qe;
const gfx::Size frame_size(320, 180);
const scoped_ptr<uint8_t[]> black_frame_data(
new uint8_t[frame_size.GetArea()]);
memset(black_frame_data.get(), 0, frame_size.GetArea());
const scoped_refptr<VideoFrame> black_frame =
CreateFrame(black_frame_data.get(), frame_size);
// A solid color frame should always generate a minimum quantizer value (4.0)
// as a key frame. If it is provided repeatedly as delta frames, the minimum
// quantizer value should be repeatedly generated since there is no difference
// between frames.
EXPECT_EQ(4.0, qe.EstimateForKeyFrame(*black_frame));
for (int i = 0; i < 3; ++i)
EXPECT_EQ(4.0, qe.EstimateForDeltaFrame(*black_frame));
const scoped_ptr<uint8_t[]> checkerboard_frame_data(
new uint8_t[frame_size.GetArea()]);
for (int i = 0, end = frame_size.GetArea(); i < end; ++i)
checkerboard_frame_data.get()[i] = (((i % 2) == 0) ? 0 : 255);
const scoped_refptr<VideoFrame> checkerboard_frame =
CreateFrame(checkerboard_frame_data.get(), frame_size);
// Now, introduce a frame with a checkerboard pattern. Half of the pixels
// will have a difference of 255, and half will have zero difference.
// Therefore, the Shannon Entropy should be 1.0 and the resulting quantizer
// estimate should be ~11.9.
EXPECT_NEAR(11.9, qe.EstimateForDeltaFrame(*checkerboard_frame), 0.1);
// Now, introduce a series of frames with "random snow" in them. Expect this
// results in high quantizer estimates.
for (int i = 0; i < 3; ++i) {
int rand_seed = 0xdeadbeef + i;
const scoped_ptr<uint8_t[]> random_frame_data(
new uint8_t[frame_size.GetArea()]);
for (int j = 0, end = frame_size.GetArea(); j < end; ++j) {
rand_seed = (1103515245 * rand_seed + 12345) % (1 << 31);
random_frame_data.get()[j] = static_cast<uint8_t>(rand_seed & 0xff);
}
const scoped_refptr<VideoFrame> random_frame =
CreateFrame(random_frame_data.get(), frame_size);
EXPECT_LE(50.0, qe.EstimateForDeltaFrame(*random_frame));
}
}
} // namespace cast
} // namespace media
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