X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=ycbcr_input.h;fp=ycbcr_input.h;h=fd9db273d52ba1a049c0ff98411f507a97ccc723;hb=9dcbd93164611ea111cc29519c18193d4f571ac1;hp=0000000000000000000000000000000000000000;hpb=ef82f39846c48a654b63797b78bf8b0b8935d348;p=movit

diff --git a/ycbcr_input.h b/ycbcr_input.h
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+++ b/ycbcr_input.h
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+#ifndef _YCBCR_INPUT_H
+#define _YCBCR_INPUT_H 1
+
+// YCbCrInput is for handling planar 8-bit Y'CbCr (also sometimes, usually rather
+// imprecisely, called “YUV”), which is typically what you get from a video decoder.
+// It upsamples planes as needed, using the default linear upsampling OpenGL gives you.
+
+#include "input.h"
+
+struct YCbCrFormat {
+	// Which formula for Y' to use.
+	YCbCrLumaCoefficients luma_coefficients;
+
+	// If true, assume Y'CbCr coefficients are full-range, ie. go from 0 to 255
+	// instead of the limited 220/225 steps in classic MPEG. For instance,
+	// JPEG uses the Rec. 601 luma coefficients, but full range.
+	bool full_range;
+
+	// Sampling factors for chroma components. For no subsampling (4:4:4),
+	// set both to 1.
+	unsigned chroma_subsampling_x, chroma_subsampling_y;
+
+	// Positioning of the chroma samples. MPEG-1 and JPEG is (0.5, 0.5);
+	// MPEG-2 and newer typically are (0.0, 0.5).
+	float chroma_x_position, chroma_y_position;
+};
+
+class YCbCrInput : public Input {
+public:
+	YCbCrInput(const ImageFormat &image_format,
+	           const YCbCrFormat &ycbcr_format,
+	           unsigned width, unsigned height);
+
+	// Create the texture itself. We cannot do this in the constructor,
+	// because we don't necessarily know all the settings (sRGB texture,
+	// mipmap generation) at that point.
+	void finalize();
+
+	virtual bool can_output_linear_gamma() const { return false; }
+
+	std::string output_fragment_shader();
+
+	// Uploads the texture if it has changed since last time.
+	void set_gl_state(GLuint glsl_program_num, const std::string& prefix, unsigned *sampler_num);
+
+	ColorSpace get_color_space() const { return image_format.color_space; }
+	GammaCurve get_gamma_curve() const { return image_format.gamma_curve; }
+
+	// Tells the input where to fetch the actual pixel data. Note that if you change
+	// this data, you must either call set_pixel_data() again (using the same pointer
+	// is fine), or invalidate_pixel_data(). Otherwise, the texture won't be re-uploaded
+	// on subsequent frames.
+	void set_pixel_data(unsigned channel, const unsigned char *pixel_data)
+	{
+		assert(channel >= 0 && channel < 3);
+		this->pixel_data[channel] = pixel_data;
+		invalidate_pixel_data();
+	}
+
+	void invalidate_pixel_data()
+	{
+		needs_update = true;
+	}
+
+	const unsigned char *get_pixel_data(unsigned channel) const
+	{
+		assert(channel >= 0 && channel < 3);
+		return pixel_data[channel];
+	}
+
+	void set_pitch(unsigned channel, unsigned pitch) {
+		assert(!finalized);
+		assert(channel >= 0 && channel < 3);
+		this->pitch[channel] = pitch;
+	}
+
+	unsigned get_pitch(unsigned channel) {
+		assert(channel >= 0 && channel < 3);
+		return pitch[channel];
+	}
+
+private:
+	ImageFormat image_format;
+	YCbCrFormat ycbcr_format;
+	GLuint pbos[3], texture_num[3];
+	bool needs_update, finalized;
+
+	int needs_mipmaps;
+
+	unsigned width, height, widths[3], heights[3];
+	const unsigned char *pixel_data[3];
+	unsigned pitch[3];
+};
+
+#endif // !defined(_YCBCR_INPUT_H)