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/*
* Copyright 2017 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.
*/
#import "RTCI420TextureCache.h"
#import <OpenGLES/ES3/gl.h>
#import "base/RTCI420Buffer.h"
#import "base/RTCVideoFrameBuffer.h"
#include <vector>
// Two sets of 3 textures are used here, one for each of the Y, U and V planes. Having two sets
// alleviates CPU blockage in the event that the GPU is asked to render to a texture that is already
// in use.
static const GLsizei kNumTextureSets = 2;
static const GLsizei kNumTexturesPerSet = 3;
static const GLsizei kNumTextures = kNumTexturesPerSet * kNumTextureSets;
@implementation RTCI420TextureCache {
BOOL _hasUnpackRowLength;
GLint _currentTextureSet;
// Handles for OpenGL constructs.
GLuint _textures[kNumTextures];
// Used to create a non-padded plane for GPU upload when we receive padded frames.
std::vector<uint8_t> _planeBuffer;
}
- (GLuint)yTexture {
return _textures[_currentTextureSet * kNumTexturesPerSet];
}
- (GLuint)uTexture {
return _textures[_currentTextureSet * kNumTexturesPerSet + 1];
}
- (GLuint)vTexture {
return _textures[_currentTextureSet * kNumTexturesPerSet + 2];
}
- (instancetype)initWithContext:(GlContextType *)context {
self = [super init];
if (self) {
_hasUnpackRowLength = (context.API == kEAGLRenderingAPIOpenGLES3);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
[self setupTextures];
}
return self;
}
- (void)dealloc {
glDeleteTextures(kNumTextures, _textures);
}
- (void)setupTextures {
glGenTextures(kNumTextures, _textures);
// Set parameters for each of the textures we created.
for (GLsizei i = 0; i < kNumTextures; i++) {
glBindTexture(GL_TEXTURE_2D, _textures[i]);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
}
}
- (void)uploadPlane:(const uint8_t *)plane
texture:(GLuint)texture
width:(size_t)width
height:(size_t)height
stride:(int32_t)stride {
glBindTexture(GL_TEXTURE_2D, texture);
const uint8_t *uploadPlane = plane;
if ((size_t)stride != width) {
if (_hasUnpackRowLength) {
// GLES3 allows us to specify stride.
glPixelStorei(GL_UNPACK_ROW_LENGTH, stride);
glTexImage2D(GL_TEXTURE_2D,
0,
RTC_PIXEL_FORMAT,
static_cast<GLsizei>(width),
static_cast<GLsizei>(height),
0,
RTC_PIXEL_FORMAT,
GL_UNSIGNED_BYTE,
uploadPlane);
glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
return;
} else {
// Make an unpadded copy and upload that instead. Quick profiling showed
// that this is faster than uploading row by row using glTexSubImage2D.
uint8_t *unpaddedPlane = _planeBuffer.data();
for (size_t y = 0; y < height; ++y) {
memcpy(unpaddedPlane + y * width, plane + y * stride, width);
}
uploadPlane = unpaddedPlane;
}
}
glTexImage2D(GL_TEXTURE_2D,
0,
RTC_PIXEL_FORMAT,
static_cast<GLsizei>(width),
static_cast<GLsizei>(height),
0,
RTC_PIXEL_FORMAT,
GL_UNSIGNED_BYTE,
uploadPlane);
}
- (void)uploadFrameToTextures:(RTC_OBJC_TYPE(RTCVideoFrame) *)frame {
_currentTextureSet = (_currentTextureSet + 1) % kNumTextureSets;
id<RTC_OBJC_TYPE(RTCI420Buffer)> buffer = [frame.buffer toI420];
const int chromaWidth = buffer.chromaWidth;
const int chromaHeight = buffer.chromaHeight;
if (buffer.strideY != frame.width || buffer.strideU != chromaWidth ||
buffer.strideV != chromaWidth) {
_planeBuffer.resize(buffer.width * buffer.height);
}
[self uploadPlane:buffer.dataY
texture:self.yTexture
width:buffer.width
height:buffer.height
stride:buffer.strideY];
[self uploadPlane:buffer.dataU
texture:self.uTexture
width:chromaWidth
height:chromaHeight
stride:buffer.strideU];
[self uploadPlane:buffer.dataV
texture:self.vTexture
width:chromaWidth
height:chromaHeight
stride:buffer.strideV];
}
@end