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// Copyright (c) 2010 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.
// This webpage shows layout of YV12 and other YUV formats
// The actual conversion is best described here
// An article on optimizing YUV conversion using tables instead of multiplies
//
// YV12 is a full plane of Y and a half height, half width chroma planes
// YV16 is a full plane of Y and a full height, half width chroma planes
// YV24 is a full plane of Y and a full height, full width chroma planes
// Y8 is a full plane of Y and no chroma planes (i.e., monochrome)
//
// ARGB pixel format is output, which on little endian is stored as BGRA.
// The alpha is set to 255, allowing the application to use RGBA or RGB32.
#include "yuv_convert.h"
#include "mozilla/StaticPrefs_gfx.h"
#include "libyuv.h"
#include "scale_yuv_argb.h"
// Header for low level row functions.
#include "yuv_row.h"
#include "mozilla/SSE.h"
#include "mozilla/IntegerRange.h"
namespace mozilla {
namespace gfx {
// 16.16 fixed point arithmetic
const int kFractionBits = 16;
const int kFractionMax = 1 << kFractionBits;
const int kFractionMask = ((1 << kFractionBits) - 1);
// clang-format off
libyuv::FourCC FourCCFromYUVType(YUVType aYUVType) {
switch (aYUVType) {
case YV24: return libyuv::FOURCC_I444;
case YV16: return libyuv::FOURCC_I422;
case YV12: return libyuv::FOURCC_I420;
case Y8: return libyuv::FOURCC_I400;
default: return libyuv::FOURCC_ANY;
}
}
int GBRPlanarToARGB(const uint8_t* src_y, int y_pitch,
const uint8_t* src_u, int u_pitch,
const uint8_t* src_v, int v_pitch,
uint8_t* rgb_buf, int rgb_pitch,
int pic_width, int pic_height) {
// libyuv has no native conversion function for this
// fixme: replace with something less awful
for (const auto row : IntegerRange(pic_height)) {
for (const auto col : IntegerRange(pic_width)) {
rgb_buf[rgb_pitch * row + col * 4 + 0] = src_u[u_pitch * row + col];
rgb_buf[rgb_pitch * row + col * 4 + 1] = src_y[y_pitch * row + col];
rgb_buf[rgb_pitch * row + col * 4 + 2] = src_v[v_pitch * row + col];
rgb_buf[rgb_pitch * row + col * 4 + 3] = 255;
}
}
return 0;
}
// Convert a frame of YUV to 32 bit ARGB.
void ConvertYCbCrToRGB32(const uint8_t* y_buf, const uint8_t* u_buf,
const uint8_t* v_buf, uint8_t* rgb_buf, int pic_x,
int pic_y, int pic_width, int pic_height, int y_pitch,
int uv_pitch, int rgb_pitch, YUVType yuv_type,
YUVColorSpace yuv_color_space,
ColorRange color_range) {
// Deprecated function's conversion is accurate.
// libyuv converion is a bit inaccurate to get performance. It dynamically
// calculates RGB from YUV to use simd. In it, signed byte is used for
// conversion's coefficient, but it requests 129. libyuv cut 129 to 127. And
// only 6 bits are used for a decimal part during the dynamic calculation.
//
// The function is still fast on some old intel chips.
bool use_deprecated = StaticPrefs::gfx_ycbcr_accurate_conversion() ||
(supports_mmx() && supports_sse() && !supports_sse3() &&
yuv_color_space == YUVColorSpace::BT601 &&
color_range == ColorRange::LIMITED);
// The deprecated function only support BT601.
if (yuv_color_space != YUVColorSpace::BT601) {
use_deprecated = false;
}
if (use_deprecated) {
ConvertYCbCrToRGB32_deprecated(y_buf, u_buf, v_buf, rgb_buf, pic_x, pic_y,
pic_width, pic_height, y_pitch, uv_pitch,
rgb_pitch, yuv_type);
return;
}
decltype(libyuv::I420ToARGBMatrix)* fConvertYUVToARGB = nullptr;
const uint8_t* src_y = nullptr;
const uint8_t* src_u = nullptr;
const uint8_t* src_v = nullptr;
const libyuv::YuvConstants* yuv_constant = nullptr;
switch (yuv_color_space) {
case YUVColorSpace::BT2020:
yuv_constant = color_range == ColorRange::LIMITED
? &libyuv::kYuv2020Constants
: &libyuv::kYuvV2020Constants;
break;
case YUVColorSpace::BT709:
yuv_constant = color_range == ColorRange::LIMITED
? &libyuv::kYuvH709Constants
: &libyuv::kYuvF709Constants;
break;
case YUVColorSpace::Identity:
MOZ_ASSERT(yuv_type == YV24, "Identity (aka RGB) with chroma subsampling is unsupported");
if (yuv_type == YV24) {
break;
}
[[fallthrough]]; // Assuming BT601 for unsupported input is better than crashing
default:
MOZ_FALLTHROUGH_ASSERT("Unsupported YUVColorSpace");
case YUVColorSpace::BT601:
yuv_constant = color_range == ColorRange::LIMITED
? &libyuv::kYuvI601Constants
: &libyuv::kYuvJPEGConstants;
break;
}
switch (yuv_type) {
case YV24: {
src_y = y_buf + y_pitch * pic_y + pic_x;
src_u = u_buf + uv_pitch * pic_y + pic_x;
src_v = v_buf + uv_pitch * pic_y + pic_x;
if (yuv_color_space == YUVColorSpace::Identity) {
// Special case for RGB image
DebugOnly<int> err =
GBRPlanarToARGB(src_y, y_pitch, src_u, uv_pitch, src_v, uv_pitch,
rgb_buf, rgb_pitch, pic_width, pic_height);
MOZ_ASSERT(!err);
return;
}
fConvertYUVToARGB = libyuv::I444ToARGBMatrix;
break;
}
case YV16: {
src_y = y_buf + y_pitch * pic_y + pic_x;
src_u = u_buf + uv_pitch * pic_y + pic_x / 2;
src_v = v_buf + uv_pitch * pic_y + pic_x / 2;
fConvertYUVToARGB = libyuv::I422ToARGBMatrix;
break;
}
case YV12: {
src_y = y_buf + y_pitch * pic_y + pic_x;
src_u = u_buf + (uv_pitch * pic_y + pic_x) / 2;
src_v = v_buf + (uv_pitch * pic_y + pic_x) / 2;
fConvertYUVToARGB = libyuv::I420ToARGBMatrix;
break;
}
case Y8: {
src_y = y_buf + y_pitch * pic_y + pic_x;
MOZ_ASSERT(u_buf == nullptr);
MOZ_ASSERT(v_buf == nullptr);
if (color_range == ColorRange::LIMITED) {
DebugOnly<int> err =
libyuv::I400ToARGB(src_y, y_pitch, rgb_buf, rgb_pitch, pic_width,
pic_height);
MOZ_ASSERT(!err);
} else {
DebugOnly<int> err =
libyuv::J400ToARGB(src_y, y_pitch, rgb_buf, rgb_pitch, pic_width,
pic_height);
MOZ_ASSERT(!err);
}
return;
}
default:
MOZ_ASSERT_UNREACHABLE("Unsupported YUV type");
}
DebugOnly<int> err =
fConvertYUVToARGB(src_y, y_pitch, src_u, uv_pitch, src_v, uv_pitch,
rgb_buf, rgb_pitch, yuv_constant, pic_width, pic_height);
MOZ_ASSERT(!err);
}
// Convert a frame of YUV to 32 bit ARGB.
void ConvertYCbCrToRGB32_deprecated(const uint8_t* y_buf,
const uint8_t* u_buf,
const uint8_t* v_buf,
uint8_t* rgb_buf,
int pic_x,
int pic_y,
int pic_width,
int pic_height,
int y_pitch,
int uv_pitch,
int rgb_pitch,
YUVType yuv_type) {
unsigned int y_shift = yuv_type == YV12 ? 1 : 0;
unsigned int x_shift = yuv_type == YV24 ? 0 : 1;
// Test for SSE because the optimized code uses movntq, which is not part of MMX.
bool has_sse = supports_mmx() && supports_sse();
// There is no optimized YV24 SSE routine so we check for this and
// fall back to the C code.
has_sse &= yuv_type != YV24;
bool odd_pic_x = yuv_type != YV24 && pic_x % 2 != 0;
int x_width = odd_pic_x ? pic_width - 1 : pic_width;
for (int y = pic_y; y < pic_height + pic_y; ++y) {
uint8_t* rgb_row = rgb_buf + (y - pic_y) * rgb_pitch;
const uint8_t* y_ptr = y_buf + y * y_pitch + pic_x;
const uint8_t* u_ptr = u_buf + (y >> y_shift) * uv_pitch + (pic_x >> x_shift);
const uint8_t* v_ptr = v_buf + (y >> y_shift) * uv_pitch + (pic_x >> x_shift);
if (odd_pic_x) {
// Handle the single odd pixel manually and use the
// fast routines for the remaining.
FastConvertYUVToRGB32Row_C(y_ptr++,
u_ptr++,
v_ptr++,
rgb_row,
1,
x_shift);
rgb_row += 4;
}
if (has_sse) {
FastConvertYUVToRGB32Row(y_ptr,
u_ptr,
v_ptr,
rgb_row,
x_width);
}
else {
FastConvertYUVToRGB32Row_C(y_ptr,
u_ptr,
v_ptr,
rgb_row,
x_width,
x_shift);
}
}
// MMX used for FastConvertYUVToRGB32Row requires emms instruction.
if (has_sse)
EMMS();
}
// C version does 8 at a time to mimic MMX code
static void FilterRows_C(uint8_t* ybuf, const uint8_t* y0_ptr, const uint8_t* y1_ptr,
int source_width, int source_y_fraction) {
int y1_fraction = source_y_fraction;
int y0_fraction = 256 - y1_fraction;
uint8_t* end = ybuf + source_width;
do {
ybuf[0] = (y0_ptr[0] * y0_fraction + y1_ptr[0] * y1_fraction) >> 8;
ybuf[1] = (y0_ptr[1] * y0_fraction + y1_ptr[1] * y1_fraction) >> 8;
ybuf[2] = (y0_ptr[2] * y0_fraction + y1_ptr[2] * y1_fraction) >> 8;
ybuf[3] = (y0_ptr[3] * y0_fraction + y1_ptr[3] * y1_fraction) >> 8;
ybuf[4] = (y0_ptr[4] * y0_fraction + y1_ptr[4] * y1_fraction) >> 8;
ybuf[5] = (y0_ptr[5] * y0_fraction + y1_ptr[5] * y1_fraction) >> 8;
ybuf[6] = (y0_ptr[6] * y0_fraction + y1_ptr[6] * y1_fraction) >> 8;
ybuf[7] = (y0_ptr[7] * y0_fraction + y1_ptr[7] * y1_fraction) >> 8;
y0_ptr += 8;
y1_ptr += 8;
ybuf += 8;
} while (ybuf < end);
}
#ifdef MOZILLA_MAY_SUPPORT_MMX
void FilterRows_MMX(uint8_t* ybuf, const uint8_t* y0_ptr, const uint8_t* y1_ptr,
int source_width, int source_y_fraction);
#endif
#ifdef MOZILLA_MAY_SUPPORT_SSE2
void FilterRows_SSE2(uint8_t* ybuf, const uint8_t* y0_ptr, const uint8_t* y1_ptr,
int source_width, int source_y_fraction);
#endif
static inline void FilterRows(uint8_t* ybuf, const uint8_t* y0_ptr,
const uint8_t* y1_ptr, int source_width,
int source_y_fraction) {
#ifdef MOZILLA_MAY_SUPPORT_SSE2
if (mozilla::supports_sse2()) {
FilterRows_SSE2(ybuf, y0_ptr, y1_ptr, source_width, source_y_fraction);
return;
}
#endif
#ifdef MOZILLA_MAY_SUPPORT_MMX
if (mozilla::supports_mmx()) {
FilterRows_MMX(ybuf, y0_ptr, y1_ptr, source_width, source_y_fraction);
return;
}
#endif
FilterRows_C(ybuf, y0_ptr, y1_ptr, source_width, source_y_fraction);
}
// Scale a frame of YUV to 32 bit ARGB.
void ScaleYCbCrToRGB32(const uint8_t* y_buf,
const uint8_t* u_buf,
const uint8_t* v_buf,
uint8_t* rgb_buf,
int source_width,
int source_height,
int width,
int height,
int y_pitch,
int uv_pitch,
int rgb_pitch,
YUVType yuv_type,
YUVColorSpace yuv_color_space,
ScaleFilter filter) {
bool use_deprecated =
StaticPrefs::gfx_ycbcr_accurate_conversion() ||
#if defined(XP_WIN) && defined(_M_X64)
supports_sse3() ||
#endif
(supports_mmx() && supports_sse() && !supports_sse3());
// The deprecated function only support BT601.
if (yuv_color_space != YUVColorSpace::BT601) {
use_deprecated = false;
}
if (use_deprecated) {
ScaleYCbCrToRGB32_deprecated(y_buf, u_buf, v_buf,
rgb_buf,
source_width, source_height,
width, height,
y_pitch, uv_pitch,
rgb_pitch,
yuv_type,
ROTATE_0,
filter);
return;
}
DebugOnly<int> err =
libyuv::YUVToARGBScale(y_buf, y_pitch,
u_buf, uv_pitch,
v_buf, uv_pitch,
FourCCFromYUVType(yuv_type),
yuv_color_space,
source_width, source_height,
rgb_buf, rgb_pitch,
width, height,
libyuv::kFilterBilinear);
MOZ_ASSERT(!err);
return;
}
// Scale a frame of YUV to 32 bit ARGB.
void ScaleYCbCrToRGB32_deprecated(const uint8_t* y_buf,
const uint8_t* u_buf,
const uint8_t* v_buf,
uint8_t* rgb_buf,
int source_width,
int source_height,
int width,
int height,
int y_pitch,
int uv_pitch,
int rgb_pitch,
YUVType yuv_type,
Rotate view_rotate,
ScaleFilter filter) {
bool has_mmx = supports_mmx();
// 4096 allows 3 buffers to fit in 12k.
// Helps performance on CPU with 16K L1 cache.
// Large enough for 3830x2160 and 30" displays which are 2560x1600.
const int kFilterBufferSize = 4096;
// Disable filtering if the screen is too big (to avoid buffer overflows).
// This should never happen to regular users: they don't have monitors
// wider than 4096 pixels.
// TODO(fbarchard): Allow rotated videos to filter.
if (source_width > kFilterBufferSize || view_rotate)
filter = FILTER_NONE;
unsigned int y_shift = yuv_type == YV12 ? 1 : 0;
// Diagram showing origin and direction of source sampling.
// ->0 4<-
// 7 3
//
// 6 5
// ->1 2<-
// Rotations that start at right side of image.
if ((view_rotate == ROTATE_180) ||
(view_rotate == ROTATE_270) ||
(view_rotate == MIRROR_ROTATE_0) ||
(view_rotate == MIRROR_ROTATE_90)) {
y_buf += source_width - 1;
u_buf += source_width / 2 - 1;
v_buf += source_width / 2 - 1;
source_width = -source_width;
}
// Rotations that start at bottom of image.
if ((view_rotate == ROTATE_90) ||
(view_rotate == ROTATE_180) ||
(view_rotate == MIRROR_ROTATE_90) ||
(view_rotate == MIRROR_ROTATE_180)) {
y_buf += (source_height - 1) * y_pitch;
u_buf += ((source_height >> y_shift) - 1) * uv_pitch;
v_buf += ((source_height >> y_shift) - 1) * uv_pitch;
source_height = -source_height;
}
// Handle zero sized destination.
if (width == 0 || height == 0)
return;
int source_dx = source_width * kFractionMax / width;
int source_dy = source_height * kFractionMax / height;
int source_dx_uv = source_dx;
if ((view_rotate == ROTATE_90) ||
(view_rotate == ROTATE_270)) {
int tmp = height;
height = width;
width = tmp;
tmp = source_height;
source_height = source_width;
source_width = tmp;
int original_dx = source_dx;
int original_dy = source_dy;
source_dx = ((original_dy >> kFractionBits) * y_pitch) << kFractionBits;
source_dx_uv = ((original_dy >> kFractionBits) * uv_pitch) << kFractionBits;
source_dy = original_dx;
if (view_rotate == ROTATE_90) {
y_pitch = -1;
uv_pitch = -1;
source_height = -source_height;
} else {
y_pitch = 1;
uv_pitch = 1;
}
}
// Need padding because FilterRows() will write 1 to 16 extra pixels
// after the end for SSE2 version.
uint8_t yuvbuf[16 + kFilterBufferSize * 3 + 16];
uint8_t* ybuf =
reinterpret_cast<uint8_t*>(reinterpret_cast<uintptr_t>(yuvbuf + 15) & ~15);
uint8_t* ubuf = ybuf + kFilterBufferSize;
uint8_t* vbuf = ubuf + kFilterBufferSize;
// TODO(fbarchard): Fixed point math is off by 1 on negatives.
int yscale_fixed = (source_height << kFractionBits) / height;
// TODO(fbarchard): Split this into separate function for better efficiency.
for (int y = 0; y < height; ++y) {
uint8_t* dest_pixel = rgb_buf + y * rgb_pitch;
int source_y_subpixel = (y * yscale_fixed);
if (yscale_fixed >= (kFractionMax * 2)) {
source_y_subpixel += kFractionMax / 2; // For 1/2 or less, center filter.
}
int source_y = source_y_subpixel >> kFractionBits;
const uint8_t* y0_ptr = y_buf + source_y * y_pitch;
const uint8_t* y1_ptr = y0_ptr + y_pitch;
const uint8_t* u0_ptr = u_buf + (source_y >> y_shift) * uv_pitch;
const uint8_t* u1_ptr = u0_ptr + uv_pitch;
const uint8_t* v0_ptr = v_buf + (source_y >> y_shift) * uv_pitch;
const uint8_t* v1_ptr = v0_ptr + uv_pitch;
// vertical scaler uses 16.8 fixed point
int source_y_fraction = (source_y_subpixel & kFractionMask) >> 8;
int source_uv_fraction =
((source_y_subpixel >> y_shift) & kFractionMask) >> 8;
const uint8_t* y_ptr = y0_ptr;
const uint8_t* u_ptr = u0_ptr;
const uint8_t* v_ptr = v0_ptr;
// Apply vertical filtering if necessary.
// TODO(fbarchard): Remove memcpy when not necessary.
if (filter & mozilla::gfx::FILTER_BILINEAR_V) {
if (yscale_fixed != kFractionMax &&
source_y_fraction && ((source_y + 1) < source_height)) {
FilterRows(ybuf, y0_ptr, y1_ptr, source_width, source_y_fraction);
} else {
memcpy(ybuf, y0_ptr, source_width);
}
y_ptr = ybuf;
ybuf[source_width] = ybuf[source_width-1];
int uv_source_width = (source_width + 1) / 2;
if (yscale_fixed != kFractionMax &&
source_uv_fraction &&
(((source_y >> y_shift) + 1) < (source_height >> y_shift))) {
FilterRows(ubuf, u0_ptr, u1_ptr, uv_source_width, source_uv_fraction);
FilterRows(vbuf, v0_ptr, v1_ptr, uv_source_width, source_uv_fraction);
} else {
memcpy(ubuf, u0_ptr, uv_source_width);
memcpy(vbuf, v0_ptr, uv_source_width);
}
u_ptr = ubuf;
v_ptr = vbuf;
ubuf[uv_source_width] = ubuf[uv_source_width - 1];
vbuf[uv_source_width] = vbuf[uv_source_width - 1];
}
if (source_dx == kFractionMax) { // Not scaled
FastConvertYUVToRGB32Row(y_ptr, u_ptr, v_ptr,
dest_pixel, width);
} else if (filter & FILTER_BILINEAR_H) {
LinearScaleYUVToRGB32Row(y_ptr, u_ptr, v_ptr,
dest_pixel, width, source_dx);
} else {
// Specialized scalers and rotation.
#if defined(MOZILLA_MAY_SUPPORT_SSE) && defined(_MSC_VER) && defined(_M_IX86) && !defined(__clang__)
if(mozilla::supports_sse()) {
if (width == (source_width * 2)) {
DoubleYUVToRGB32Row_SSE(y_ptr, u_ptr, v_ptr,
dest_pixel, width);
} else if ((source_dx & kFractionMask) == 0) {
// Scaling by integer scale factor. ie half.
ConvertYUVToRGB32Row_SSE(y_ptr, u_ptr, v_ptr,
dest_pixel, width,
source_dx >> kFractionBits);
} else if (source_dx_uv == source_dx) { // Not rotated.
ScaleYUVToRGB32Row(y_ptr, u_ptr, v_ptr,
dest_pixel, width, source_dx);
} else {
RotateConvertYUVToRGB32Row_SSE(y_ptr, u_ptr, v_ptr,
dest_pixel, width,
source_dx >> kFractionBits,
source_dx_uv >> kFractionBits);
}
}
else {
ScaleYUVToRGB32Row_C(y_ptr, u_ptr, v_ptr,
dest_pixel, width, source_dx);
}
#else
(void)source_dx_uv;
ScaleYUVToRGB32Row(y_ptr, u_ptr, v_ptr,
dest_pixel, width, source_dx);
#endif
}
}
// MMX used for FastConvertYUVToRGB32Row and FilterRows requires emms.
if (has_mmx)
EMMS();
}
void ConvertI420AlphaToARGB32(const uint8_t* y_buf,
const uint8_t* u_buf,
const uint8_t* v_buf,
const uint8_t* a_buf,
uint8_t* argb_buf,
int pic_width,
int pic_height,
int ya_pitch,
int uv_pitch,
int argb_pitch) {
// The downstream graphics stack expects an attenuated input, hence why the
// attenuation parameter is set.
DebugOnly<int> err = libyuv::I420AlphaToARGB(y_buf, ya_pitch,
u_buf, uv_pitch,
v_buf, uv_pitch,
a_buf, ya_pitch,
argb_buf, argb_pitch,
pic_width, pic_height, 1);
MOZ_ASSERT(!err);
}
} // namespace gfx
} // namespace mozilla