| /* |
| * 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 "RTCMTLI420Renderer.h" |
| |
| #import <Metal/Metal.h> |
| #import <MetalKit/MetalKit.h> |
| |
| #import "base/RTCI420Buffer.h" |
| #import "base/RTCLogging.h" |
| #import "base/RTCVideoFrame.h" |
| #import "base/RTCVideoFrameBuffer.h" |
| |
| #import "RTCMTLRenderer+Private.h" |
| |
| static NSString *const shaderSource = MTL_STRINGIFY( |
| using namespace metal; |
| |
| typedef struct { |
| packed_float2 position; |
| packed_float2 texcoord; |
| } Vertex; |
| |
| typedef struct { |
| float4 position[[position]]; |
| float2 texcoord; |
| } Varyings; |
| |
| vertex Varyings vertexPassthrough(device Vertex * verticies[[buffer(0)]], |
| unsigned int vid[[vertex_id]]) { |
| Varyings out; |
| device Vertex &v = verticies[vid]; |
| out.position = float4(float2(v.position), 0.0, 1.0); |
| out.texcoord = v.texcoord; |
| |
| return out; |
| } |
| |
| fragment half4 fragmentColorConversion( |
| Varyings in[[stage_in]], texture2d<float, access::sample> textureY[[texture(0)]], |
| texture2d<float, access::sample> textureU[[texture(1)]], |
| texture2d<float, access::sample> textureV[[texture(2)]]) { |
| constexpr sampler s(address::clamp_to_edge, filter::linear); |
| float y; |
| float u; |
| float v; |
| float r; |
| float g; |
| float b; |
| // Conversion for YUV to rgb from http://www.fourcc.org/fccyvrgb.php |
| y = textureY.sample(s, in.texcoord).r; |
| u = textureU.sample(s, in.texcoord).r; |
| v = textureV.sample(s, in.texcoord).r; |
| u = u - 0.5; |
| v = v - 0.5; |
| r = y + 1.403 * v; |
| g = y - 0.344 * u - 0.714 * v; |
| b = y + 1.770 * u; |
| |
| float4 out = float4(r, g, b, 1.0); |
| |
| return half4(out); |
| }); |
| |
| @implementation RTCMTLI420Renderer { |
| // Textures. |
| id<MTLTexture> _yTexture; |
| id<MTLTexture> _uTexture; |
| id<MTLTexture> _vTexture; |
| |
| MTLTextureDescriptor *_descriptor; |
| MTLTextureDescriptor *_chromaDescriptor; |
| |
| int _width; |
| int _height; |
| int _chromaWidth; |
| int _chromaHeight; |
| } |
| |
| #pragma mark - Virtual |
| |
| - (NSString *)shaderSource { |
| return shaderSource; |
| } |
| |
| - (void)getWidth:(nonnull int *)width |
| height:(nonnull int *)height |
| cropWidth:(nonnull int *)cropWidth |
| cropHeight:(nonnull int *)cropHeight |
| cropX:(nonnull int *)cropX |
| cropY:(nonnull int *)cropY |
| ofFrame:(nonnull RTCVideoFrame *)frame { |
| *width = frame.width; |
| *height = frame.height; |
| *cropWidth = frame.width; |
| *cropHeight = frame.height; |
| *cropX = 0; |
| *cropY = 0; |
| } |
| |
| - (BOOL)setupTexturesForFrame:(nonnull RTCVideoFrame *)frame { |
| if (![super setupTexturesForFrame:frame]) { |
| return NO; |
| } |
| |
| id<MTLDevice> device = [self currentMetalDevice]; |
| if (!device) { |
| return NO; |
| } |
| |
| id<RTCI420Buffer> buffer = [frame.buffer toI420]; |
| |
| // Luma (y) texture. |
| if (!_descriptor || _width != frame.width || _height != frame.height) { |
| _width = frame.width; |
| _height = frame.height; |
| _descriptor = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatR8Unorm |
| width:_width |
| height:_height |
| mipmapped:NO]; |
| _descriptor.usage = MTLTextureUsageShaderRead; |
| _yTexture = [device newTextureWithDescriptor:_descriptor]; |
| } |
| |
| // Chroma (u,v) textures |
| [_yTexture replaceRegion:MTLRegionMake2D(0, 0, _width, _height) |
| mipmapLevel:0 |
| withBytes:buffer.dataY |
| bytesPerRow:buffer.strideY]; |
| |
| if (!_chromaDescriptor || _chromaWidth != frame.width / 2 || _chromaHeight != frame.height / 2) { |
| _chromaWidth = frame.width / 2; |
| _chromaHeight = frame.height / 2; |
| _chromaDescriptor = |
| [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatR8Unorm |
| width:_chromaWidth |
| height:_chromaHeight |
| mipmapped:NO]; |
| _chromaDescriptor.usage = MTLTextureUsageShaderRead; |
| _uTexture = [device newTextureWithDescriptor:_chromaDescriptor]; |
| _vTexture = [device newTextureWithDescriptor:_chromaDescriptor]; |
| } |
| |
| [_uTexture replaceRegion:MTLRegionMake2D(0, 0, _chromaWidth, _chromaHeight) |
| mipmapLevel:0 |
| withBytes:buffer.dataU |
| bytesPerRow:buffer.strideU]; |
| [_vTexture replaceRegion:MTLRegionMake2D(0, 0, _chromaWidth, _chromaHeight) |
| mipmapLevel:0 |
| withBytes:buffer.dataV |
| bytesPerRow:buffer.strideV]; |
| |
| return (_uTexture != nil) && (_yTexture != nil) && (_vTexture != nil); |
| } |
| |
| - (void)uploadTexturesToRenderEncoder:(id<MTLRenderCommandEncoder>)renderEncoder { |
| [renderEncoder setFragmentTexture:_yTexture atIndex:0]; |
| [renderEncoder setFragmentTexture:_uTexture atIndex:1]; |
| [renderEncoder setFragmentTexture:_vTexture atIndex:2]; |
| } |
| |
| @end |