score::gfx::NV12Decoder Struct Reference

Decodes NV12 videos. More...

Inheritance diagram for score::gfx::NV12Decoder:

Detailed Description

Decodes NV12 videos.

Mostly follow the YUV420 shader, things are just laid out differently in memory

Public Member Functions
	NV12Decoder (Video::ImageFormat &d, bool inverted)
std::pair< QShader, QShader >	init (RenderList &r) override
	Initialize a GPUVideoDecoder. More...
void	exec (RenderList &, QRhiResourceUpdateBatch &res, AVFrame &frame) override
	Decode and upload a video frame to the GPU.
void	setYPixels (QRhiResourceUpdateBatch &res, uint8_t *pixels, int stride) const noexcept
void	setUVPixels (QRhiResourceUpdateBatch &res, uint8_t *pixels, int stride) const noexcept
Public Member Functions inherited from score::gfx::GPUVideoDecoder
void	release (RenderList &)
	This method will release all the created samplers and textures.

Public Attributes
Video::ImageFormat &	decoder
bool	nv21 {}
Public Attributes inherited from score::gfx::GPUVideoDecoder
std::vector< Sampler >	samplers

Static Public Attributes
static constexpr const auto	nv12_filter_prologue
static constexpr const auto	nv12_filter_epilogue

Additional Inherited Members
Static Public Member Functions inherited from score::gfx::GPUVideoDecoder
static QRhiTextureSubresourceUploadDescription	createTextureUpload (uint8_t *pixels, int w, int h, int bytesPerPixel, int stride)
	Utility method to create a QRhiTextureSubresourceUploadDescription. More...
static QString	vertexShader () noexcept

Member Function Documentation

init()

std::pair<QShader, QShader> score::gfx::NV12Decoder::init ( RenderList &  r )

inlineoverridevirtual

Initialize a GPUVideoDecoder.

This method must :

• Create samplers and textures for the video format.
• Create shaders that will render the data put into these textures.

It returns a {vertex, fragment} shader pair.

Implements score::gfx::GPUVideoDecoder.

Member Data Documentation

nv12_filter_epilogue

constexpr const auto score::gfx::NV12Decoder::nv12_filter_epilogue

staticconstexpr

Initial value:

= R"_(
 
    yuv += offset;
    fragColor = vec4(0.0, 0.0, 0.0, 1.0);
    fragColor.r = dot(yuv, R_cf);
    fragColor.g = dot(yuv, G_cf);
    fragColor.b = dot(yuv, B_cf);
  })_"

nv12_filter_prologue

constexpr const auto score::gfx::NV12Decoder::nv12_filter_prologue

staticconstexpr

Initial value:

= R"_(#version 450
 
)_" SCORE_GFX_VIDEO_UNIFORMS R"_(
 
  layout(binding=3) uniform sampler2D y_tex;
  layout(binding=4) uniform sampler2D uv_tex;
 
  layout(location = 0) in vec2 v_texcoord;
  layout(location = 0) out vec4 fragColor;
 
  const vec3 R_cf = vec3(1.164383,  0.000000,  1.596027);
  const vec3 G_cf = vec3(1.164383, -0.391762, -0.812968);
  const vec3 B_cf = vec3(1.164383,  2.017232,  0.000000);
  const vec3 offset = vec3(-0.0625, -0.5, -0.5);
 
  void main ()
  {
    float y = texture(y_tex, v_texcoord).r;
    float u = texture(uv_tex, v_texcoord).r;
    float v = texture(uv_tex, v_texcoord).a;
 
)_"

---

The documentation for this struct was generated from the following file:

• NV12.hpp