vo_opengl: remove sharpen scalers, add sharpen sub-option

This turns the old scalers (inherited from MPlayer) into a pre-
processing step (after color conversion and before scaling). The code
for the "sharpen5" scaler is reused for this.

The main reason MPlayer implemented this as scalers was perhaps because
FBOs were too expensive, and making it a scaler allowed to implement
this in 1 pass. But unsharp masking is not really a scaler, and I would
guess the result is more like combining bilinear scaling and unsharp
masking.

4 files changed, 34 insertions, 46 deletions

diff --git a/video/out/opengl/video.c b/video/out/opengl/video.c
index 21bebafc30..291e98d0a8 100644
--- a/video/out/opengl/video.c
+++ b/video/out/opengl/video.c
@@ -53,8 +53,6 @@
 static const char *const fixed_scale_filters[] = {
     "bilinear",
     "bicubic_fast",
-    "sharpen3",
-    "sharpen5",
     "oversample",
     "custom",
     NULL
@@ -167,6 +165,7 @@ struct gl_video {
     struct fbotex chroma_deband_fbo;
     struct fbotex indirect_fbo;
     struct fbotex blend_subs_fbo;
+    struct fbotex unsharp_fbo;
     struct fbosurface surfaces[FBOSURFACES_MAX];
 
     // these are duplicated so we can keep rendering back and forth between
@@ -427,6 +426,7 @@ const struct m_sub_options gl_video_conf = {
         OPT_STRINGLIST("post-shaders", post_shaders, 0),
         OPT_FLAG("deband", deband, 0),
         OPT_SUBSTRUCT("deband", deband_opts, deband_conf, 0),
+        OPT_FLOAT("sharpen", unsharp, 0),
 
         OPT_REMOVED("approx-gamma", "this is always enabled now"),
         OPT_REMOVED("cscale-down", "chroma is never downscaled"),
@@ -576,6 +576,7 @@ static void uninit_rendering(struct gl_video *p)
     fbotex_uninit(&p->chroma_deband_fbo);
     fbotex_uninit(&p->indirect_fbo);
     fbotex_uninit(&p->blend_subs_fbo);
+    fbotex_uninit(&p->unsharp_fbo);
 
     for (int n = 0; n < 2; n++) {
         fbotex_uninit(&p->pre_fbo[n]);
@@ -1098,10 +1099,6 @@ static void pass_sample(struct gl_video *p, int src_tex, struct scaler *scaler,
         GLSL(vec4 color = texture(tex, pos);)
     } else if (strcmp(name, "bicubic_fast") == 0) {
         pass_sample_bicubic_fast(p->sc);
-    } else if (strcmp(name, "sharpen3") == 0) {
-        pass_sample_sharpen3(p->sc, scaler);
-    } else if (strcmp(name, "sharpen5") == 0) {
-        pass_sample_sharpen5(p->sc, scaler);
     } else if (strcmp(name, "oversample") == 0) {
         pass_sample_oversample(p->sc, scaler, w, h);
     } else if (strcmp(name, "custom") == 0) {
@@ -1666,6 +1663,11 @@ static void pass_render_frame(struct gl_video *p)
     apply_shaders(p, p->opts.pre_shaders, &p->pre_fbo[0], 0,
                   p->image_w, p->image_h);
 
+    if (p->opts.unsharp != 0.0) {
+        finish_pass_fbo(p, &p->unsharp_fbo, p->image_w, p->image_h, 0, 0);
+        pass_sample_unsharp(p->sc, p->opts.unsharp);
+    }
+
     pass_scale_main(p);
 
     int vp_w = p->dst_rect.x1 - p->dst_rect.x0,
diff --git a/video/out/opengl/video.h b/video/out/opengl/video.h
index f03cac9c34..c5aa6c4913 100644
--- a/video/out/opengl/video.h
+++ b/video/out/opengl/video.h
@@ -98,6 +98,7 @@ struct gl_video_opts {
     char **post_shaders;
     int deband;
     struct deband_opts *deband_opts;
+    float unsharp;
 };
 
 extern const struct m_sub_options gl_video_conf;
diff --git a/video/out/opengl/video_shaders.c b/video/out/opengl/video_shaders.c
index 2ea57b781d..90cfba5166 100644
--- a/video/out/opengl/video_shaders.c
+++ b/video/out/opengl/video_shaders.c
@@ -200,44 +200,6 @@ void pass_sample_bicubic_fast(struct gl_shader_cache *sc)
     GLSLF("}\n");
 }
 
-void pass_sample_sharpen3(struct gl_shader_cache *sc, struct scaler *scaler)
-{
-    GLSL(vec4 color;)
-    GLSLF("{\n");
-    GLSL(vec2 st = pt * 0.5;)
-    GLSL(vec4 p = texture(tex, pos);)
-    GLSL(vec4 sum = texture(tex, pos + st * vec2(+1, +1))
-                  + texture(tex, pos + st * vec2(+1, -1))
-                  + texture(tex, pos + st * vec2(-1, +1))
-                  + texture(tex, pos + st * vec2(-1, -1));)
-    float param = scaler->conf.kernel.params[0];
-    param = isnan(param) ? 0.5 : param;
-    GLSLF("color = p + (p - 0.25 * sum) * %f;\n", param);
-    GLSLF("}\n");
-}
-
-void pass_sample_sharpen5(struct gl_shader_cache *sc, struct scaler *scaler)
-{
-    GLSL(vec4 color;)
-    GLSLF("{\n");
-    GLSL(vec2 st1 = pt * 1.2;)
-    GLSL(vec4 p = texture(tex, pos);)
-    GLSL(vec4 sum1 = texture(tex, pos + st1 * vec2(+1, +1))
-                   + texture(tex, pos + st1 * vec2(+1, -1))
-                   + texture(tex, pos + st1 * vec2(-1, +1))
-                   + texture(tex, pos + st1 * vec2(-1, -1));)
-    GLSL(vec2 st2 = pt * 1.5;)
-    GLSL(vec4 sum2 = texture(tex, pos + st2 * vec2(+1,  0))
-                   + texture(tex, pos + st2 * vec2( 0, +1))
-                   + texture(tex, pos + st2 * vec2(-1,  0))
-                   + texture(tex, pos + st2 * vec2( 0, -1));)
-    GLSL(vec4 t = p * 0.859375 + sum2 * -0.1171875 + sum1 * -0.09765625;)
-    float param = scaler->conf.kernel.params[0];
-    param = isnan(param) ? 0.5 : param;
-    GLSLF("color = p + t * %f;\n", param);
-    GLSLF("}\n");
-}
-
 void pass_sample_oversample(struct gl_shader_cache *sc, struct scaler *scaler,
                                    int w, int h)
 {
@@ -435,3 +397,26 @@ void pass_sample_deband(struct gl_shader_cache *sc, struct deband_opts *opts,
     GLSL(noise.z = rand(h); h = permute(h);)
     GLSLF("color.xyz += %f * (noise - vec3(0.5));\n", opts->grain/8192.0);
 }
+
+void pass_sample_unsharp(struct gl_shader_cache *sc, float param)
+{
+    GLSLF("// unsharp\n");
+    sampler_prelude(sc, 0);
+
+    GLSL(vec4 color;)
+    GLSLF("{\n");
+    GLSL(vec2 st1 = pt * 1.2;)
+    GLSL(vec4 p = texture(tex, pos);)
+    GLSL(vec4 sum1 = texture(tex, pos + st1 * vec2(+1, +1))
+                   + texture(tex, pos + st1 * vec2(+1, -1))
+                   + texture(tex, pos + st1 * vec2(-1, +1))
+                   + texture(tex, pos + st1 * vec2(-1, -1));)
+    GLSL(vec2 st2 = pt * 1.5;)
+    GLSL(vec4 sum2 = texture(tex, pos + st2 * vec2(+1,  0))
+                   + texture(tex, pos + st2 * vec2( 0, +1))
+                   + texture(tex, pos + st2 * vec2(-1,  0))
+                   + texture(tex, pos + st2 * vec2( 0, -1));)
+    GLSL(vec4 t = p * 0.859375 + sum2 * -0.1171875 + sum1 * -0.09765625;)
+    GLSLF("color = p + t * %f;\n", param);
+    GLSLF("}\n");
+}
diff --git a/video/out/opengl/video_shaders.h b/video/out/opengl/video_shaders.h
index aa4afa2289..e5f031cb26 100644
--- a/video/out/opengl/video_shaders.h
+++ b/video/out/opengl/video_shaders.h
@@ -37,8 +37,6 @@ void pass_sample_separated_gen(struct gl_shader_cache *sc, struct scaler *scaler
                                int d_x, int d_y);
 void pass_sample_polar(struct gl_shader_cache *sc, struct scaler *scaler);
 void pass_sample_bicubic_fast(struct gl_shader_cache *sc);
-void pass_sample_sharpen3(struct gl_shader_cache *sc, struct scaler *scaler);
-void pass_sample_sharpen5(struct gl_shader_cache *sc, struct scaler *scaler);
 void pass_sample_oversample(struct gl_shader_cache *sc, struct scaler *scaler,
                             int w, int h);
 
@@ -49,4 +47,6 @@ void pass_sample_deband(struct gl_shader_cache *sc, struct deband_opts *opts,
                         int tex_num, GLenum tex_target, float tex_mul,
                         float img_w, float img_h, AVLFG *lfg);
 
+void pass_sample_unsharp(struct gl_shader_cache *sc, float param);
+
 #endif