Source code
Revision control
Copy as Markdown
Other Tools
/*
* Copyright (c) 2018 The WebRTC 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 "rtc_tools/frame_analyzer/video_geometry_aligner.h"
#include <map>
#include "api/make_ref_counted.h"
#include "api/video/i420_buffer.h"
#include "rtc_base/checks.h"
#include "rtc_tools/frame_analyzer/video_quality_analysis.h"
#include "third_party/libyuv/include/libyuv/scale.h"
namespace webrtc {
namespace test {
namespace {
bool IsValidRegion(const CropRegion& region,
const rtc::scoped_refptr<I420BufferInterface>& frame) {
return region.left >= 0 && region.right >= 0 && region.top >= 0 &&
region.bottom >= 0 && region.left + region.right < frame->width() &&
region.top + region.bottom < frame->height();
}
} // namespace
rtc::scoped_refptr<I420BufferInterface> CropAndZoom(
const CropRegion& crop_region,
const rtc::scoped_refptr<I420BufferInterface>& frame) {
RTC_CHECK(IsValidRegion(crop_region, frame));
const int uv_crop_left = crop_region.left / 2;
const int uv_crop_top = crop_region.top / 2;
const int cropped_width =
frame->width() - crop_region.left - crop_region.right;
const int cropped_height =
frame->height() - crop_region.top - crop_region.bottom;
// Crop by only adjusting pointers.
const uint8_t* y_plane =
frame->DataY() + frame->StrideY() * crop_region.top + crop_region.left;
const uint8_t* u_plane =
frame->DataU() + frame->StrideU() * uv_crop_top + uv_crop_left;
const uint8_t* v_plane =
frame->DataV() + frame->StrideV() * uv_crop_top + uv_crop_left;
// Stretch the cropped frame to the original size using libyuv.
rtc::scoped_refptr<I420Buffer> adjusted_frame =
I420Buffer::Create(frame->width(), frame->height());
libyuv::I420Scale(y_plane, frame->StrideY(), u_plane, frame->StrideU(),
v_plane, frame->StrideV(), cropped_width, cropped_height,
adjusted_frame->MutableDataY(), adjusted_frame->StrideY(),
adjusted_frame->MutableDataU(), adjusted_frame->StrideU(),
adjusted_frame->MutableDataV(), adjusted_frame->StrideV(),
frame->width(), frame->height(), libyuv::kFilterBox);
return adjusted_frame;
}
CropRegion CalculateCropRegion(
const rtc::scoped_refptr<I420BufferInterface>& reference_frame,
const rtc::scoped_refptr<I420BufferInterface>& test_frame) {
RTC_CHECK_EQ(reference_frame->width(), test_frame->width());
RTC_CHECK_EQ(reference_frame->height(), test_frame->height());
CropRegion best_region;
double best_ssim = Ssim(reference_frame, test_frame);
typedef int CropRegion::*CropParameter;
CropParameter crop_parameters[4] = {&CropRegion::left, &CropRegion::top,
&CropRegion::right, &CropRegion::bottom};
while (true) {
// Find the parameter in which direction SSIM improves the most.
CropParameter best_parameter = nullptr;
const CropRegion prev_best_region = best_region;
for (CropParameter crop_parameter : crop_parameters) {
CropRegion test_region = prev_best_region;
++(test_region.*crop_parameter);
if (!IsValidRegion(test_region, reference_frame))
continue;
const double ssim =
Ssim(CropAndZoom(test_region, reference_frame), test_frame);
if (ssim > best_ssim) {
best_ssim = ssim;
best_parameter = crop_parameter;
best_region = test_region;
}
}
// No improvement among any direction, stop iteration.
if (best_parameter == nullptr)
break;
// Iterate in the best direction as long as it improves SSIM.
for (CropRegion test_region = best_region;
IsValidRegion(test_region, reference_frame);
++(test_region.*best_parameter)) {
const double ssim =
Ssim(CropAndZoom(test_region, reference_frame), test_frame);
if (ssim <= best_ssim)
break;
best_ssim = ssim;
best_region = test_region;
}
}
return best_region;
}
rtc::scoped_refptr<I420BufferInterface> AdjustCropping(
const rtc::scoped_refptr<I420BufferInterface>& reference_frame,
const rtc::scoped_refptr<I420BufferInterface>& test_frame) {
return CropAndZoom(CalculateCropRegion(reference_frame, test_frame),
reference_frame);
}
rtc::scoped_refptr<Video> AdjustCropping(
const rtc::scoped_refptr<Video>& reference_video,
const rtc::scoped_refptr<Video>& test_video) {
class CroppedVideo : public Video {
public:
CroppedVideo(const rtc::scoped_refptr<Video>& reference_video,
const rtc::scoped_refptr<Video>& test_video)
: reference_video_(reference_video), test_video_(test_video) {
RTC_CHECK_EQ(reference_video->number_of_frames(),
test_video->number_of_frames());
RTC_CHECK_EQ(reference_video->width(), test_video->width());
RTC_CHECK_EQ(reference_video->height(), test_video->height());
}
int width() const override { return test_video_->width(); }
int height() const override { return test_video_->height(); }
size_t number_of_frames() const override {
return test_video_->number_of_frames();
}
rtc::scoped_refptr<I420BufferInterface> GetFrame(
size_t index) const override {
const rtc::scoped_refptr<I420BufferInterface> reference_frame =
reference_video_->GetFrame(index);
// Only calculate cropping region once per frame since it's expensive.
if (!crop_regions_.count(index)) {
crop_regions_[index] =
CalculateCropRegion(reference_frame, test_video_->GetFrame(index));
}
return CropAndZoom(crop_regions_[index], reference_frame);
}
private:
const rtc::scoped_refptr<Video> reference_video_;
const rtc::scoped_refptr<Video> test_video_;
// Mutable since this is a cache that affects performance and not logical
// behavior.
mutable std::map<size_t, CropRegion> crop_regions_;
};
return rtc::make_ref_counted<CroppedVideo>(reference_video, test_video);
}
} // namespace test
} // namespace webrtc