Add CUDA acceleration support

app/app.pro

@@ -182,6 +182,7 @@ ffmpeg {
     SOURCES += \
         streaming/video/ffmpeg.cpp \
         streaming/video/ffmpeg-renderers/sdlvid.cpp \
+        streaming/video/ffmpeg-renderers/cuda.cpp \
         streaming/video/ffmpeg-renderers/pacer/pacer.cpp \
         streaming/video/ffmpeg-renderers/pacer/nullthreadedvsyncsource.cpp
 
@@ -189,6 +190,7 @@ ffmpeg {
         streaming/video/ffmpeg.h \
         streaming/video/ffmpeg-renderers/renderer.h \
         streaming/video/ffmpeg-renderers/sdlvid.h \
+        streaming/video/ffmpeg-renderers/cuda.h \
         streaming/video/ffmpeg-renderers/pacer/pacer.h \
         streaming/video/ffmpeg-renderers/pacer/nullthreadedvsyncsource.h
 }

app/streaming/video/ffmpeg-renderers/cuda.cpp

@@ -0,0 +1,57 @@
+#include "cuda.h"
+
+CUDARenderer::CUDARenderer()
+    : m_HwContext(nullptr)
+{
+
+}
+
+CUDARenderer::~CUDARenderer()
+{
+    if (m_HwContext != nullptr) {
+        av_buffer_unref(&m_HwContext);
+    }
+}
+
+bool CUDARenderer::initialize(PDECODER_PARAMETERS)
+{
+    int err;
+
+    err = av_hwdevice_ctx_create(&m_HwContext, AV_HWDEVICE_TYPE_CUDA, nullptr, nullptr, 0);
+    if (err != 0) {
+        SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
+                     "av_hwdevice_ctx_create(CUDA) failed: %d",
+                     err);
+        return false;
+    }
+
+    return true;
+}
+
+bool CUDARenderer::prepareDecoderContext(AVCodecContext* context)
+{
+    context->hw_device_ctx = av_buffer_ref(m_HwContext);
+
+    SDL_LogInfo(SDL_LOG_CATEGORY_APPLICATION,
+                "Using CUDA accelerated decoder");
+
+    return true;
+}
+
+void CUDARenderer::renderFrame(AVFrame*)
+{
+    // We only support indirect rendering
+    SDL_assert(false);
+}
+
+bool CUDARenderer::needsTestFrame()
+{
+    return true;
+}
+
+bool CUDARenderer::isDirectRenderingSupported()
+{
+    // We only support rendering via SDL read-back
+    return false;
+}
+

app/streaming/video/ffmpeg-renderers/cuda.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "renderer.h"
+
+class CUDARenderer : public IFFmpegRenderer {
+public:
+    CUDARenderer();
+    virtual ~CUDARenderer() override;
+    virtual bool initialize(PDECODER_PARAMETERS) override;
+    virtual bool prepareDecoderContext(AVCodecContext* context) override;
+    virtual void renderFrame(AVFrame* frame) override;
+    virtual bool needsTestFrame() override;
+    virtual bool isDirectRenderingSupported() override;
+
+private:
+    AVBufferRef* m_HwContext;
+};
+