sdl video push conversion stream and toxav video sink

src/frame_streams/sdl/video_push_converter.cpp

@@ -0,0 +1,58 @@
+#include "./video_push_converter.hpp"
+
+SDL_Surface* convertYUY2_IYUV(SDL_Surface* surf) {
+	if (surf->format != SDL_PIXELFORMAT_YUY2) {
+		return nullptr;
+	}
+	if ((surf->w % 2) != 0) {
+		SDL_SetError("YUY2->IYUV does not support odd widths");
+		// hmmm, we dont handle odd widths
+		return nullptr;
+	}
+
+	SDL_LockSurface(surf);
+
+	SDL_Surface* conv_surf = SDL_CreateSurface(surf->w, surf->h, SDL_PIXELFORMAT_IYUV);
+	SDL_LockSurface(conv_surf);
+
+	// YUY2 is 4:2:2 packed
+	// Y is simple, we just copy it over
+	// U V are double the resolution (vertically), so we avg both
+	// Packed mode: Y0+U0+Y1+V0 (1 plane)
+
+	uint8_t* y_plane = static_cast<uint8_t*>(conv_surf->pixels);
+	uint8_t* u_plane = static_cast<uint8_t*>(conv_surf->pixels) + conv_surf->w*conv_surf->h;
+	uint8_t* v_plane = static_cast<uint8_t*>(conv_surf->pixels) + conv_surf->w*conv_surf->h + (conv_surf->w/2)*(conv_surf->h/2);
+
+	const uint8_t* yuy2_data = static_cast<const uint8_t*>(surf->pixels);
+
+	for (int y = 0; y < surf->h; y++) {
+		for (int x = 0; x < surf->w; x += 2) {
+			// every pixel uses 2 bytes
+			const uint8_t* yuy2_curser = yuy2_data + y*surf->w*2 + x*2;
+			uint8_t src_y0 = yuy2_curser[0];
+			uint8_t src_u = yuy2_curser[1];
+			uint8_t src_y1 = yuy2_curser[2];
+			uint8_t src_v = yuy2_curser[3];
+
+			y_plane[y*conv_surf->w + x] = src_y0;
+			y_plane[y*conv_surf->w + x+1] = src_y1;
+
+			size_t uv_index = (y/2) * (conv_surf->w/2) + x/2;
+			if (y % 2 == 0) {
+				// first write
+				u_plane[uv_index] = src_u;
+				v_plane[uv_index] = src_v;
+			} else {
+				// second write, mix with existing value
+				u_plane[uv_index] = (int(u_plane[uv_index]) + int(src_u)) / 2;
+				v_plane[uv_index] = (int(v_plane[uv_index]) + int(src_v)) / 2;
+			}
+		}
+	}
+
+	SDL_UnlockSurface(conv_surf);
+	SDL_UnlockSurface(surf);
+	return conv_surf;
+}
+

src/frame_streams/sdl/video_push_converter.hpp

@@ -0,0 +1,89 @@
+#pragma once
+
+#include "./video.hpp"
+#include "../frame_stream2.hpp"
+
+#include <cassert>
+
+#include <iostream> // meh
+
+static bool isFormatYUV(SDL_PixelFormat f) {
+	return
+		f == SDL_PIXELFORMAT_YV12 ||
+		f == SDL_PIXELFORMAT_IYUV ||
+		f == SDL_PIXELFORMAT_YUY2 ||
+		f == SDL_PIXELFORMAT_UYVY ||
+		f == SDL_PIXELFORMAT_YVYU ||
+		f == SDL_PIXELFORMAT_NV12 ||
+		f == SDL_PIXELFORMAT_NV21 ||
+		f == SDL_PIXELFORMAT_P010
+	;
+}
+
+SDL_Surface* convertYUY2_IYUV(SDL_Surface* surf);
+
+template<typename RealStream>
+struct PushConversionVideoStream : public RealStream {
+	SDL_PixelFormat _forced_format {SDL_PIXELFORMAT_IYUV};
+
+	template<typename... Args>
+	PushConversionVideoStream(SDL_PixelFormat forced_format, Args&&... args) : RealStream(std::forward<Args>(args)...), _forced_format(forced_format) {}
+	~PushConversionVideoStream(void) {}
+
+	bool push(const SDLVideoFrame& value) override {
+		SDL_Surface* surf = value.surface.get();
+		if (surf->format != _forced_format) {
+			//std::cerr << "DTC: need to convert from " << SDL_GetPixelFormatName(converted_surf->format) << " to SDL_PIXELFORMAT_IYUV\n";
+			if (surf->format == SDL_PIXELFORMAT_YUY2 && _forced_format == SDL_PIXELFORMAT_IYUV) {
+				// optimized custom impl
+
+				//auto start = Message::getTimeMS();
+				surf = convertYUY2_IYUV(surf);
+				//auto end = Message::getTimeMS();
+				// 3ms
+				//std::cerr << "DTC: timing " << SDL_GetPixelFormatName(converted_surf->format) << "->SDL_PIXELFORMAT_IYUV: " << end-start << "ms\n";
+			} else if (isFormatYUV(surf->format)) {
+				// TODO: fix sdl rgb->yuv conversion resulting in too dark (colorspace) issues
+				// https://github.com/libsdl-org/SDL/issues/10877
+
+				// meh, need to convert to rgb as a stopgap
+
+				//auto start = Message::getTimeMS();
+				SDL_Surface* tmp_conv_surf = SDL_ConvertSurfaceAndColorspace(surf, SDL_PIXELFORMAT_RGB24, nullptr, SDL_COLORSPACE_RGB_DEFAULT, 0);
+				//auto end = Message::getTimeMS();
+				// 1ms
+				//std::cerr << "DTC: timing " << SDL_GetPixelFormatName(converted_surf->format) << "->SDL_PIXELFORMAT_RGB24: " << end-start << "ms\n";
+
+				//start = Message::getTimeMS();
+				surf = SDL_ConvertSurfaceAndColorspace(tmp_conv_surf, _forced_format, nullptr, SDL_COLORSPACE_YUV_DEFAULT, 0);
+				//end = Message::getTimeMS();
+				// 60ms
+				//std::cerr << "DTC: timing SDL_PIXELFORMAT_RGB24->" << SDL_GetPixelFormatName(_forced_format) << ": " << end-start << "ms\n";
+
+				SDL_DestroySurface(tmp_conv_surf);
+			} else {
+				surf = SDL_ConvertSurface(surf, _forced_format);
+			}
+
+			if (surf == nullptr) {
+				// oh god
+				std::cerr << "DTC error: failed to convert surface to IYUV: " << SDL_GetError() << "\n";
+				return false;
+			}
+		}
+		assert(surf != nullptr);
+		if (surf != value.surface.get()) {
+			// TODO: add ctr with uptr
+			SDLVideoFrame new_value{value.timestampUS, nullptr};
+			new_value.surface = {
+				surf,
+				&SDL_DestroySurface
+			};
+
+			return RealStream::push(std::move(new_value));
+		} else {
+			return RealStream::push(value);
+		}
+	}
+};
+