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-rw-r--r--src/shaders/deinterlacing.c260
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diff --git a/src/shaders/deinterlacing.c b/src/shaders/deinterlacing.c
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+++ b/src/shaders/deinterlacing.c
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+/*
+ * This file is part of libplacebo, but also based on vf_yadif_cuda.cu:
+ * Copyright (C) 2018 Philip Langdale <philipl@overt.org>
+ *
+ * libplacebo is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * libplacebo is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with libplacebo. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "shaders.h"
+
+#include <libplacebo/shaders/deinterlacing.h>
+
+const struct pl_deinterlace_params pl_deinterlace_default_params = { PL_DEINTERLACE_DEFAULTS };
+
+void pl_shader_deinterlace(pl_shader sh, const struct pl_deinterlace_source *src,
+ const struct pl_deinterlace_params *params)
+{
+ params = PL_DEF(params, &pl_deinterlace_default_params);
+
+ const struct pl_tex_params *texparams = &src->cur.top->params;
+ if (!sh_require(sh, PL_SHADER_SIG_NONE, texparams->w, texparams->h))
+ return;
+
+ sh_describe(sh, "deinterlacing");
+ GLSL("vec4 color = vec4(0,0,0,1); \n"
+ "// pl_shader_deinterlace \n"
+ "{ \n");
+
+ uint8_t comp_mask = PL_DEF(src->component_mask, 0xFu);
+ comp_mask &= (1u << texparams->format->num_components) - 1u;
+ if (!comp_mask) {
+ SH_FAIL(sh, "pl_shader_deinterlace: empty component mask?");
+ return;
+ }
+
+ const uint8_t num_comps = sh_num_comps(comp_mask);
+ const char *swiz = sh_swizzle(comp_mask);
+ GLSL("#define T %s \n", sh_float_type(comp_mask));
+
+ ident_t pos, pt;
+ ident_t cur = sh_bind(sh, src->cur.top, PL_TEX_ADDRESS_MIRROR,
+ PL_TEX_SAMPLE_NEAREST, "cur", NULL, &pos, &pt);
+ if (!cur)
+ return;
+
+ GLSL("#define GET(TEX, X, Y) \\\n"
+ " (textureLod(TEX, pos + pt * vec2(X, Y), 0.0).%s) \n"
+ "vec2 pos = "$"; \n"
+ "vec2 pt = "$"; \n"
+ "T res; \n",
+ swiz, pos, pt);
+
+ if (src->field == PL_FIELD_NONE) {
+ GLSL("res = GET("$", 0, 0); \n", cur);
+ goto done;
+ }
+
+ // Don't modify the primary field
+ GLSL("int yh = textureSize("$", 0).y; \n"
+ "int yo = int("$".y * float(yh)); \n"
+ "if (yo %% 2 == %d) { \n"
+ " res = GET("$", 0, 0); \n"
+ "} else { \n",
+ cur, pos,
+ src->field == PL_FIELD_TOP ? 0 : 1,
+ cur);
+
+ switch (params->algo) {
+ case PL_DEINTERLACE_WEAVE:
+ GLSL("res = GET("$", 0, 0); \n", cur);
+ break;
+
+ case PL_DEINTERLACE_BOB:
+ GLSL("res = GET("$", 0, %d); \n", cur,
+ src->field == PL_FIELD_TOP ? -1 : 1);
+ break;
+
+
+ case PL_DEINTERLACE_YADIF: {
+ // Try using a compute shader for this, for the sole reason of
+ // optimizing for thread group synchronicity. Otherwise, because we
+ // alternate between lines output as-is and lines output deinterlaced,
+ // half of our thread group will be mostly idle at any point in time.
+ const int bw = PL_DEF(sh_glsl(sh).subgroup_size, 32);
+ sh_try_compute(sh, bw, 1, true, 0);
+
+ // This magic constant is hard-coded in the original implementation as
+ // '1' on an 8-bit scale. Since we work with arbitrary bit depth
+ // floating point textures, we have to convert this somehow. Hard-code
+ // it as 1/255 under the assumption that the original intent was to be
+ // roughly 1 unit of brightness increment on an 8-bit source. This may
+ // or may not produce suboptimal results on higher-bit-depth content.
+ static const float spatial_bias = 1 / 255.0f;
+
+ // Calculate spatial prediction
+ ident_t spatial_pred = sh_fresh(sh, "spatial_predictor");
+ GLSLH("float "$"(float a, float b, float c, float d, float e, float f, float g, \n"
+ " float h, float i, float j, float k, float l, float m, float n) \n"
+ "{ \n"
+ " float spatial_pred = (d + k) / 2.0; \n"
+ " float spatial_score = abs(c - j) + abs(d - k) + abs(e - l) - %f; \n"
+
+ " float score = abs(b - k) + abs(c - l) + abs(d - m); \n"
+ " if (score < spatial_score) { \n"
+ " spatial_pred = (c + l) / 2.0; \n"
+ " spatial_score = score; \n"
+ " score = abs(a - l) + abs(b - m) + abs(c - n); \n"
+ " if (score < spatial_score) { \n"
+ " spatial_pred = (b + m) / 2.0; \n"
+ " spatial_score = score; \n"
+ " } \n"
+ " } \n"
+ " score = abs(d - i) + abs(e - j) + abs(f - k); \n"
+ " if (score < spatial_score) { \n"
+ " spatial_pred = (e + j) / 2.0; \n"
+ " spatial_score = score; \n"
+ " score = abs(e - h) + abs(f - i) + abs(g - j); \n"
+ " if (score < spatial_score) { \n"
+ " spatial_pred = (f + i) / 2.0; \n"
+ " spatial_score = score; \n"
+ " } \n"
+ " } \n"
+ " return spatial_pred; \n"
+ "} \n",
+ spatial_pred, spatial_bias);
+
+ GLSL("T a = GET("$", -3, -1); \n"
+ "T b = GET("$", -2, -1); \n"
+ "T c = GET("$", -1, -1); \n"
+ "T d = GET("$", 0, -1); \n"
+ "T e = GET("$", +1, -1); \n"
+ "T f = GET("$", +2, -1); \n"
+ "T g = GET("$", +3, -1); \n"
+ "T h = GET("$", -3, +1); \n"
+ "T i = GET("$", -2, +1); \n"
+ "T j = GET("$", -1, +1); \n"
+ "T k = GET("$", 0, +1); \n"
+ "T l = GET("$", +1, +1); \n"
+ "T m = GET("$", +2, +1); \n"
+ "T n = GET("$", +3, +1); \n",
+ cur, cur, cur, cur, cur, cur, cur, cur, cur, cur, cur, cur, cur, cur);
+
+ if (num_comps == 1) {
+ GLSL("res = "$"(a, b, c, d, e, f, g, h, i, j, k, l, m, n); \n", spatial_pred);
+ } else {
+ for (uint8_t i = 0; i < num_comps; i++) {
+ char c = "xyzw"[i];
+ GLSL("res.%c = "$"(a.%c, b.%c, c.%c, d.%c, e.%c, f.%c, g.%c, \n"
+ " h.%c, i.%c, j.%c, k.%c, l.%c, m.%c, n.%c); \n",
+ c, spatial_pred, c, c, c, c, c, c, c, c, c, c, c, c, c, c);
+ }
+ }
+
+ // Calculate temporal prediction
+ ident_t temporal_pred = sh_fresh(sh, "temporal_predictor");
+ GLSLH("float "$"(float A, float B, float C, float D, float E, float F, \n"
+ " float G, float H, float I, float J, float K, float L, \n"
+ " float spatial_pred) \n"
+ "{ \n"
+ " float p0 = (C + H) / 2.0; \n"
+ " float p1 = F; \n"
+ " float p2 = (D + I) / 2.0; \n"
+ " float p3 = G; \n"
+ " float p4 = (E + J) / 2.0; \n"
+
+ " float tdiff0 = abs(D - I) / 2.0; \n"
+ " float tdiff1 = (abs(A - F) + abs(B - G)) / 2.0; \n"
+ " float tdiff2 = (abs(K - F) + abs(G - L)) / 2.0; \n"
+ " float diff = max(tdiff0, max(tdiff1, tdiff2)); \n",
+ temporal_pred);
+ if (!params->skip_spatial_check) {
+ GLSLH("float maxi = max(p2 - min(p3, p1), min(p0 - p1, p4 - p3)); \n"
+ "float mini = min(p2 - max(p3, p1), max(p0 - p1, p4 - p3)); \n"
+ "diff = max(diff, max(mini, -maxi)); \n");
+ }
+ GLSLH(" if (spatial_pred > p2 + diff) \n"
+ " spatial_pred = p2 + diff; \n"
+ " if (spatial_pred < p2 - diff) \n"
+ " spatial_pred = p2 - diff; \n"
+ " return spatial_pred; \n"
+ "} \n");
+
+ ident_t prev2 = cur, next2 = cur;
+ if (src->prev.top && src->prev.top != src->cur.top) {
+ pl_assert(src->prev.top->params.w == texparams->w);
+ pl_assert(src->prev.top->params.h == texparams->h);
+ prev2 = sh_bind(sh, src->prev.top, PL_TEX_ADDRESS_MIRROR,
+ PL_TEX_SAMPLE_NEAREST, "prev", NULL, NULL, NULL);
+ if (!prev2)
+ return;
+ }
+
+ if (src->next.top && src->next.top != src->cur.top) {
+ pl_assert(src->next.top->params.w == texparams->w);
+ pl_assert(src->next.top->params.h == texparams->h);
+ next2 = sh_bind(sh, src->next.top, PL_TEX_ADDRESS_MIRROR,
+ PL_TEX_SAMPLE_NEAREST, "next", NULL, NULL, NULL);
+ if (!next2)
+ return;
+ }
+
+ enum pl_field first_field = PL_DEF(src->first_field, PL_FIELD_TOP);
+ ident_t prev1 = src->field == first_field ? prev2 : cur;
+ ident_t next1 = src->field == first_field ? cur : next2;
+
+ GLSL("T A = GET("$", 0, -1); \n"
+ "T B = GET("$", 0, 1); \n"
+ "T C = GET("$", 0, -2); \n"
+ "T D = GET("$", 0, 0); \n"
+ "T E = GET("$", 0, +2); \n"
+ "T F = GET("$", 0, -1); \n"
+ "T G = GET("$", 0, +1); \n"
+ "T H = GET("$", 0, -2); \n"
+ "T I = GET("$", 0, 0); \n"
+ "T J = GET("$", 0, +2); \n"
+ "T K = GET("$", 0, -1); \n"
+ "T L = GET("$", 0, +1); \n",
+ prev2, prev2,
+ prev1, prev1, prev1,
+ cur, cur,
+ next1, next1, next1,
+ next2, next2);
+
+ if (num_comps == 1) {
+ GLSL("res = "$"(A, B, C, D, E, F, G, H, I, J, K, L, res); \n", temporal_pred);
+ } else {
+ for (uint8_t i = 0; i < num_comps; i++) {
+ char c = "xyzw"[i];
+ GLSL("res.%c = "$"(A.%c, B.%c, C.%c, D.%c, E.%c, F.%c, \n"
+ " G.%c, H.%c, I.%c, J.%c, K.%c, L.%c, \n"
+ " res.%c); \n",
+ c, temporal_pred, c, c, c, c, c, c, c, c, c, c, c, c, c);
+ }
+ }
+ break;
+ }
+
+ case PL_DEINTERLACE_ALGORITHM_COUNT:
+ pl_unreachable();
+ }
+
+ GLSL("}\n"); // End of primary/secondary field branch
+
+done:
+ GLSL("color.%s = res; \n"
+ "#undef T \n"
+ "#undef GET \n"
+ "} \n",
+ swiz);
+}
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