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content / browser / media / capture / frame_test_util.cc [blame]
// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/342213636): Remove this and spanify to fix the errors.
#pragma allow_unsafe_buffers
#endif
#include "content/browser/media/capture/frame_test_util.h"
#include <stdint.h>
#include <cmath>
#include "base/numerics/safe_conversions.h"
#include "media/base/video_frame.h"
#include "media/base/video_types.h"
#include "third_party/skia/include/core/SkColor.h"
#include "third_party/skia/include/core/SkColorSpace.h"
#include "third_party/skia/include/core/SkTypes.h"
#include "ui/gfx/color_space.h"
#include "ui/gfx/color_transform.h"
#include "ui/gfx/geometry/rect.h"
#include "ui/gfx/geometry/rect_conversions.h"
#include "ui/gfx/geometry/rect_f.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/geometry/transform.h"
namespace content {
namespace {
using TriStim = gfx::ColorTransform::TriStim;
// Copies YUV row data into an array of TriStims, mapping [0,255]⇒[0.0,1.0]. The
// chroma planes are assumed to be half-width.
void LoadStimsFromYUV(const uint8_t y_src[],
const uint8_t u_src[],
const uint8_t v_src[],
int width,
TriStim stims[]) {
for (int i = 0; i < width; ++i) {
stims[i].SetPoint(y_src[i] / 255.0f, u_src[i / 2] / 255.0f,
v_src[i / 2] / 255.0f);
}
}
void LoadStimsFromYUV(const uint8_t y_src[],
const uint16_t uv_src[],
int width,
TriStim stims[]) {
// https://docs.microsoft.com/en-us/windows/win32/medfound/recommended-8-bit-yuv-formats-for-video-rendering#nv12
// "All of the Y samples appear first in memory as an array of unsigned char
// values with an even number of lines. The Y plane is followed immediately by
// an array of unsigned char values that contains packed U (Cb) and V (Cr)
// samples. When the combined U-V array is addressed as an array of
// little-endian WORD values, the LSBs contain the U values, and the MSBs
// contain the V values."
#if defined(SK_CPU_BENDIAN)
for (int i = 0; i < width; ++i) {
stims[i].SetPoint(
y_src[i] / 255.0f,
(uv_src[i / 2] >> 8) / 255.0f, // MSB contains U values on LE
(uv_src[i / 2] & 0xFF) / 255.0f);
}
#else
for (int i = 0; i < width; ++i) {
stims[i].SetPoint(
y_src[i] / 255.0f,
(uv_src[i / 2] & 0xFF) / 255.0f, // LSB contains U values on LE
(uv_src[i / 2] >> 8) / 255.0f);
}
#endif
}
// Maps [0.0,1.0]⇒[0,255], rounding to the nearest integer.
uint8_t QuantizeAndClamp(float value) {
return base::saturated_cast<uint8_t>(
std::fma(value, 255.0f, 0.5f /* rounding */));
}
// Copies the array of TriStims to the BGRA/RGBA output, mapping
// [0.0,1.0]⇒[0,255].
void StimsToN32Row(const TriStim row[], int width, uint8_t bgra_out[]) {
for (int i = 0; i < width; ++i) {
bgra_out[(i * 4) + (SK_R32_SHIFT / 8)] = QuantizeAndClamp(row[i].x());
bgra_out[(i * 4) + (SK_G32_SHIFT / 8)] = QuantizeAndClamp(row[i].y());
bgra_out[(i * 4) + (SK_B32_SHIFT / 8)] = QuantizeAndClamp(row[i].z());
bgra_out[(i * 4) + (SK_A32_SHIFT / 8)] = 255;
}
}
} // namespace
// static
SkBitmap FrameTestUtil::ConvertToBitmap(const media::VideoFrame& frame) {
CHECK(frame.ColorSpace().IsValid());
SkBitmap bitmap;
bitmap.allocPixels(SkImageInfo::MakeN32Premul(frame.visible_rect().width(),
frame.visible_rect().height(),
SkColorSpace::MakeSRGB()));
// Note: The hand-optimized libyuv::H420ToARGB() would be more-desirable for
// runtime performance. However, while it claims to convert from the REC709
// color space to sRGB, as of this writing, it does not do so accurately. For
// example, a YUV triplet that should become almost exactly yellow (0xffff01)
// is converted as 0xfeff0c (the blue channel has a difference of 11!). Since
// one goal of these tests is to confirm color space correctness, the
// following color transformation code is provided:
// Construct the ColorTransform.
const auto transform = gfx::ColorTransform::NewColorTransform(
frame.ColorSpace(), gfx::ColorSpace::CreateSRGB());
CHECK(transform);
// Convert one row at a time.
std::vector<gfx::ColorTransform::TriStim> stims(bitmap.width());
for (int row = 0; row < bitmap.height(); ++row) {
if (frame.format() == media::VideoPixelFormat::PIXEL_FORMAT_I420) {
LoadStimsFromYUV(
frame.visible_data(media::VideoFrame::Plane::kY) +
row * frame.stride(media::VideoFrame::Plane::kY),
frame.visible_data(media::VideoFrame::Plane::kU) +
(row / 2) * frame.stride(media::VideoFrame::Plane::kU),
frame.visible_data(media::VideoFrame::Plane::kV) +
(row / 2) * frame.stride(media::VideoFrame::Plane::kV),
bitmap.width(), stims.data());
} else {
CHECK_EQ(frame.format(), media::VideoPixelFormat::PIXEL_FORMAT_NV12);
LoadStimsFromYUV(
frame.visible_data(media::VideoFrame::Plane::kY) +
row * frame.stride(media::VideoFrame::Plane::kY),
reinterpret_cast<const uint16_t*>(
frame.visible_data(media::VideoFrame::Plane::kUV) +
(row / 2) * frame.stride(media::VideoFrame::Plane::kUV)),
bitmap.width(), stims.data());
}
transform->Transform(stims.data(), stims.size());
StimsToN32Row(stims.data(), bitmap.width(),
reinterpret_cast<uint8_t*>(bitmap.getAddr32(0, row)));
}
return bitmap;
}
// static
gfx::Rect FrameTestUtil::ToSafeIncludeRect(const gfx::RectF& rect_f,
int fuzzy_border) {
gfx::Rect result = gfx::ToEnclosedRect(rect_f);
CHECK_GT(result.width(), 2 * fuzzy_border);
CHECK_GT(result.height(), 2 * fuzzy_border);
result.Inset(fuzzy_border);
return result;
}
// static
gfx::Rect FrameTestUtil::ToSafeExcludeRect(const gfx::RectF& rect_f,
int fuzzy_border) {
gfx::Rect result = gfx::ToEnclosingRect(rect_f);
result.Inset(-fuzzy_border);
return result;
}
// static
FrameTestUtil::RGB FrameTestUtil::ComputeAverageColor(
SkBitmap frame,
const gfx::Rect& raw_include_rect,
const gfx::Rect& raw_exclude_rect) {
// Clip the rects to the valid region within |frame|. Also, only the subregion
// of |exclude_rect| within |include_rect| is relevant.
gfx::Rect include_rect = raw_include_rect;
include_rect.Intersect(gfx::Rect(0, 0, frame.width(), frame.height()));
gfx::Rect exclude_rect = raw_exclude_rect;
exclude_rect.Intersect(include_rect);
// Sum up the color values in each color channel for all pixels in
// |include_rect| not contained by |exclude_rect|.
int64_t include_sums[3] = {0};
for (int y = include_rect.y(), bottom = include_rect.bottom(); y < bottom;
++y) {
for (int x = include_rect.x(), right = include_rect.right(); x < right;
++x) {
if (exclude_rect.Contains(x, y)) {
continue;
}
const SkColor color = frame.getColor(x, y);
include_sums[0] += SkColorGetR(color);
include_sums[1] += SkColorGetG(color);
include_sums[2] += SkColorGetB(color);
}
}
// Divide the sums by the area to compute the average color.
const int include_area =
include_rect.size().GetArea() - exclude_rect.size().GetArea();
if (include_area <= 0) {
return RGB{NAN, NAN, NAN};
} else {
const auto include_area_f = static_cast<double>(include_area);
return RGB{include_sums[0] / include_area_f,
include_sums[1] / include_area_f,
include_sums[2] / include_area_f};
}
}
// static
bool FrameTestUtil::IsApproximatelySameColor(SkColor color,
const RGB& rgb,
int max_diff) {
const double r_diff = std::abs(SkColorGetR(color) - rgb.r);
const double g_diff = std::abs(SkColorGetG(color) - rgb.g);
const double b_diff = std::abs(SkColorGetB(color) - rgb.b);
return r_diff < max_diff && g_diff < max_diff && b_diff < max_diff;
}
// static
bool FrameTestUtil::IsApproximatelySameColor(SkColor color,
SkColor expected_color,
int max_diff) {
const int r_diff = std::abs(static_cast<int>(SkColorGetR(color)) -
static_cast<int>(SkColorGetR(expected_color)));
const int g_diff = std::abs(static_cast<int>(SkColorGetG(color)) -
static_cast<int>(SkColorGetG(expected_color)));
const int b_diff = std::abs(static_cast<int>(SkColorGetB(color)) -
static_cast<int>(SkColorGetB(expected_color)));
return r_diff < max_diff && g_diff < max_diff && b_diff < max_diff;
}
bool FrameTestUtil::IsApproximatelySameColor(SkBitmap frame,
const gfx::Rect& raw_include_rect,
const gfx::Rect& raw_exclude_rect,
SkColor expected_color,
int max_diff) {
// Clip the rects to the valid region within |frame|. Also, only the subregion
// of |exclude_rect| within |include_rect| is relevant.
gfx::Rect include_rect = raw_include_rect;
include_rect.Intersect(gfx::Rect(0, 0, frame.width(), frame.height()));
gfx::Rect exclude_rect = raw_exclude_rect;
exclude_rect.Intersect(include_rect);
for (int y = include_rect.y(), bottom = include_rect.bottom(); y < bottom;
++y) {
for (int x = include_rect.x(), right = include_rect.right(); x < right;
++x) {
if (exclude_rect.Contains(x, y)) {
continue;
}
const SkColor color = frame.getColor(x, y);
if (!IsApproximatelySameColor(color, expected_color, max_diff)) {
return false;
}
}
}
return true;
}
// static
gfx::RectF FrameTestUtil::TransformSimilarly(const gfx::Rect& original,
const gfx::RectF& transformed,
const gfx::Rect& rect) {
if (original.IsEmpty()) {
return gfx::RectF(transformed.x() - original.x(),
transformed.y() - original.y(), 0.0f, 0.0f);
}
return gfx::MapRect(gfx::RectF(rect), gfx::RectF(original), transformed);
}
std::ostream& operator<<(std::ostream& out, const FrameTestUtil::RGB& rgb) {
return (out << "{r=" << rgb.r << ",g=" << rgb.g << ",b=" << rgb.b << '}');
}
} // namespace content