]> git.sesse.net Git - movit/blobdiff - gamma_expansion_effect.h
In ResampleEffect, precompute the Lanczos function into a table.
[movit] / gamma_expansion_effect.h
index 497a38c7ec4f756d1f222f300d897dc9d51f8e24..20a5a76fba04315d74f9aa09502eaac3e196e658 100644 (file)
@@ -1,15 +1,46 @@
-#ifndef _GAMMA_EXPANSION_EFFECT_H 
-#define _GAMMA_EXPANSION_EFFECT_H 1
+#ifndef _MOVIT_GAMMA_EXPANSION_EFFECT_H 
+#define _MOVIT_GAMMA_EXPANSION_EFFECT_H 1
+
+// An effect to convert the given gamma curve into linear light,
+// typically inserted by the framework automatically at the beginning
+// of the processing chain.
+//
+// Currently supports sRGB, Rec. 601/709 and Rec. 2020 (10- and 12-bit).
+// Note that Movit's internal formats generally do not have enough accuracy
+// for 12-bit input or output.
+
+#include <epoxy/gl.h>
+#include <string>
 
 #include "effect.h"
-#include "effect_chain.h"
+#include "image_format.h"
+
+namespace movit {
 
 class GammaExpansionEffect : public Effect {
-public:
+private:
+       // Should not be instantiated by end users.
        GammaExpansionEffect();
+       friend class EffectChain;
+
+public:
+       virtual std::string effect_type_id() const { return "GammaExpansionEffect"; }
+       std::string output_fragment_shader();
+       virtual void set_gl_state(GLuint glsl_program_num, const std::string &prefix, unsigned *sampler_num);
+
+       virtual bool needs_linear_light() const { return false; }
+       virtual bool needs_srgb_primaries() const { return false; }
+       virtual bool one_to_one_sampling() const { return true; }
+
+       // Actually processes its input in a nonlinear fashion,
+       // but does not touch alpha, and we are a special case anyway.
+       virtual AlphaHandling alpha_handling() const { return DONT_CARE_ALPHA_TYPE; }
 
 private:
        GammaCurve source_curve;
+       float uniform_linear_scale, uniform_c0, uniform_c1, uniform_c2, uniform_c3, uniform_c4, uniform_beta;
 };
 
-#endif // !defined(_GAMMA_EXPANSION_EFFECT_H)
+}  // namespace movit
+
+#endif // !defined(_MOVIT_GAMMA_EXPANSION_EFFECT_H)