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Diffstat (limited to 'video/out/gpu/video_shaders.c')
| -rw-r--r-- | video/out/gpu/video_shaders.c | 1033 |
1 files changed, 1033 insertions, 0 deletions
diff --git a/video/out/gpu/video_shaders.c b/video/out/gpu/video_shaders.c new file mode 100644 index 0000000..6c0e8a8 --- /dev/null +++ b/video/out/gpu/video_shaders.c @@ -0,0 +1,1033 @@ +/* + * This file is part of mpv. + * + * mpv 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. + * + * mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <math.h> + +#include "video_shaders.h" +#include "video.h" + +#define GLSL(x) gl_sc_add(sc, #x "\n"); +#define GLSLF(...) gl_sc_addf(sc, __VA_ARGS__) +#define GLSLH(x) gl_sc_hadd(sc, #x "\n"); +#define GLSLHF(...) gl_sc_haddf(sc, __VA_ARGS__) + +// Set up shared/commonly used variables and macros +void sampler_prelude(struct gl_shader_cache *sc, int tex_num) +{ + GLSLF("#undef tex\n"); + GLSLF("#undef texmap\n"); + GLSLF("#define tex texture%d\n", tex_num); + GLSLF("#define texmap texmap%d\n", tex_num); + GLSLF("vec2 pos = texcoord%d;\n", tex_num); + GLSLF("vec2 size = texture_size%d;\n", tex_num); + GLSLF("vec2 pt = pixel_size%d;\n", tex_num); +} + +static void pass_sample_separated_get_weights(struct gl_shader_cache *sc, + struct scaler *scaler) +{ + gl_sc_uniform_texture(sc, "lut", scaler->lut); + GLSLF("float ypos = LUT_POS(fcoord, %d.0);\n", scaler->lut->params.h); + + int N = scaler->kernel->size; + int width = (N + 3) / 4; // round up + + GLSLF("float weights[%d];\n", N); + for (int i = 0; i < N; i++) { + if (i % 4 == 0) + GLSLF("c = texture(lut, vec2(%f, ypos));\n", (i / 4 + 0.5) / width); + GLSLF("weights[%d] = c[%d];\n", i, i % 4); + } +} + +// Handle a single pass (either vertical or horizontal). The direction is given +// by the vector (d_x, d_y). If the vector is 0, then planar interpolation is +// used instead (samples from texture0 through textureN) +void pass_sample_separated_gen(struct gl_shader_cache *sc, struct scaler *scaler, + int d_x, int d_y) +{ + int N = scaler->kernel->size; + bool use_ar = scaler->conf.antiring > 0; + bool planar = d_x == 0 && d_y == 0; + GLSL(color = vec4(0.0);) + GLSLF("{\n"); + if (!planar) { + GLSLF("vec2 dir = vec2(%d.0, %d.0);\n", d_x, d_y); + GLSL(pt *= dir;) + GLSL(float fcoord = dot(fract(pos * size - vec2(0.5)), dir);) + GLSLF("vec2 base = pos - fcoord * pt - pt * vec2(%d.0);\n", N / 2 - 1); + } + GLSL(vec4 c;) + if (use_ar) { + GLSL(vec4 hi = vec4(0.0);) + GLSL(vec4 lo = vec4(1.0);) + } + pass_sample_separated_get_weights(sc, scaler); + GLSLF("// scaler samples\n"); + for (int n = 0; n < N; n++) { + if (planar) { + GLSLF("c = texture(texture%d, texcoord%d);\n", n, n); + } else { + GLSLF("c = texture(tex, base + pt * vec2(%d.0));\n", n); + } + GLSLF("color += vec4(weights[%d]) * c;\n", n); + if (use_ar && (n == N/2-1 || n == N/2)) { + GLSL(lo = min(lo, c);) + GLSL(hi = max(hi, c);) + } + } + if (use_ar) + GLSLF("color = mix(color, clamp(color, lo, hi), %f);\n", + scaler->conf.antiring); + GLSLF("}\n"); +} + +// Subroutine for computing and adding an individual texel contribution +// If planar is false, samples directly +// If planar is true, takes the pixel from inX[idx] where X is the component and +// `idx` must be defined by the caller +static void polar_sample(struct gl_shader_cache *sc, struct scaler *scaler, + int x, int y, int components, bool planar) +{ + double radius = scaler->kernel->radius * scaler->kernel->filter_scale; + double radius_cutoff = scaler->kernel->radius_cutoff; + + // Since we can't know the subpixel position in advance, assume a + // worst case scenario + int yy = y > 0 ? y-1 : y; + int xx = x > 0 ? x-1 : x; + double dmax = sqrt(xx*xx + yy*yy); + // Skip samples definitely outside the radius + if (dmax >= radius_cutoff) + return; + GLSLF("d = length(vec2(%d.0, %d.0) - fcoord);\n", x, y); + // Check for samples that might be skippable + bool maybe_skippable = dmax >= radius_cutoff - M_SQRT2; + if (maybe_skippable) + GLSLF("if (d < %f) {\n", radius_cutoff); + + // get the weight for this pixel + if (scaler->lut->params.dimensions == 1) { + GLSLF("w = tex1D(lut, LUT_POS(d * 1.0/%f, %d.0)).r;\n", + radius, scaler->lut->params.w); + } else { + GLSLF("w = texture(lut, vec2(0.5, LUT_POS(d * 1.0/%f, %d.0))).r;\n", + radius, scaler->lut->params.h); + } + GLSL(wsum += w;) + + if (planar) { + for (int n = 0; n < components; n++) + GLSLF("color[%d] += w * in%d[idx];\n", n, n); + } else { + GLSLF("in0 = texture(tex, base + pt * vec2(%d.0, %d.0));\n", x, y); + GLSL(color += vec4(w) * in0;) + } + + if (maybe_skippable) + GLSLF("}\n"); +} + +void pass_sample_polar(struct gl_shader_cache *sc, struct scaler *scaler, + int components, bool sup_gather) +{ + GLSL(color = vec4(0.0);) + GLSLF("{\n"); + GLSL(vec2 fcoord = fract(pos * size - vec2(0.5));) + GLSL(vec2 base = pos - fcoord * pt;) + GLSLF("float w, d, wsum = 0.0;\n"); + for (int n = 0; n < components; n++) + GLSLF("vec4 in%d;\n", n); + GLSL(int idx;) + + gl_sc_uniform_texture(sc, "lut", scaler->lut); + + GLSLF("// scaler samples\n"); + int bound = ceil(scaler->kernel->radius_cutoff); + for (int y = 1-bound; y <= bound; y += 2) { + for (int x = 1-bound; x <= bound; x += 2) { + // First we figure out whether it's more efficient to use direct + // sampling or gathering. The problem is that gathering 4 texels + // only to discard some of them is very wasteful, so only do it if + // we suspect it will be a win rather than a loss. This is the case + // exactly when all four texels are within bounds + bool use_gather = sqrt(x*x + y*y) < scaler->kernel->radius_cutoff; + + if (!sup_gather) + use_gather = false; + + if (use_gather) { + // Gather the four surrounding texels simultaneously + for (int n = 0; n < components; n++) { + GLSLF("in%d = textureGatherOffset(tex, base, " + "ivec2(%d, %d), %d);\n", n, x, y, n); + } + + // Mix in all of the points with their weights + for (int p = 0; p < 4; p++) { + // The four texels are gathered counterclockwise starting + // from the bottom left + static const int xo[4] = {0, 1, 1, 0}; + static const int yo[4] = {1, 1, 0, 0}; + if (x+xo[p] > bound || y+yo[p] > bound) + continue; + GLSLF("idx = %d;\n", p); + polar_sample(sc, scaler, x+xo[p], y+yo[p], components, true); + } + } else { + // switch to direct sampling instead, for efficiency/compatibility + for (int yy = y; yy <= bound && yy <= y+1; yy++) { + for (int xx = x; xx <= bound && xx <= x+1; xx++) + polar_sample(sc, scaler, xx, yy, components, false); + } + } + } + } + + GLSL(color = color / vec4(wsum);) + GLSLF("}\n"); +} + +// bw/bh: block size +// iw/ih: input size (pre-calculated to fit all required texels) +void pass_compute_polar(struct gl_shader_cache *sc, struct scaler *scaler, + int components, int bw, int bh, int iw, int ih) +{ + int bound = ceil(scaler->kernel->radius_cutoff); + int offset = bound - 1; // padding top/left + + GLSL(color = vec4(0.0);) + GLSLF("{\n"); + GLSL(vec2 wpos = texmap(gl_WorkGroupID * gl_WorkGroupSize);) + GLSL(vec2 wbase = wpos - pt * fract(wpos * size - vec2(0.5));) + GLSL(vec2 fcoord = fract(pos * size - vec2(0.5));) + GLSL(vec2 base = pos - pt * fcoord;) + GLSL(ivec2 rel = ivec2(round((base - wbase) * size));) + GLSL(int idx;) + GLSLF("float w, d, wsum = 0.0;\n"); + gl_sc_uniform_texture(sc, "lut", scaler->lut); + + // Load all relevant texels into shmem + for (int c = 0; c < components; c++) + GLSLHF("shared float in%d[%d];\n", c, ih * iw); + + GLSL(vec4 c;) + GLSLF("for (int y = int(gl_LocalInvocationID.y); y < %d; y += %d) {\n", ih, bh); + GLSLF("for (int x = int(gl_LocalInvocationID.x); x < %d; x += %d) {\n", iw, bw); + GLSLF("c = texture(tex, wbase + pt * vec2(x - %d, y - %d));\n", offset, offset); + for (int c = 0; c < components; c++) + GLSLF("in%d[%d * y + x] = c[%d];\n", c, iw, c); + GLSLF("}}\n"); + GLSL(groupMemoryBarrier();) + GLSL(barrier();) + + // Dispatch the actual samples + GLSLF("// scaler samples\n"); + for (int y = 1-bound; y <= bound; y++) { + for (int x = 1-bound; x <= bound; x++) { + GLSLF("idx = %d * rel.y + rel.x + %d;\n", iw, + iw * (y + offset) + x + offset); + polar_sample(sc, scaler, x, y, components, true); + } + } + + GLSL(color = color / vec4(wsum);) + GLSLF("}\n"); +} + +static void bicubic_calcweights(struct gl_shader_cache *sc, const char *t, const char *s) +{ + // Explanation of how bicubic scaling with only 4 texel fetches is done: + // http://www.mate.tue.nl/mate/pdfs/10318.pdf + // 'Efficient GPU-Based Texture Interpolation using Uniform B-Splines' + // Explanation why this algorithm normally always blurs, even with unit + // scaling: + // http://bigwww.epfl.ch/preprints/ruijters1001p.pdf + // 'GPU Prefilter for Accurate Cubic B-spline Interpolation' + GLSLF("vec4 %s = vec4(-0.5, 0.1666, 0.3333, -0.3333) * %s" + " + vec4(1, 0, -0.5, 0.5);\n", t, s); + GLSLF("%s = %s * %s + vec4(0, 0, -0.5, 0.5);\n", t, t, s); + GLSLF("%s = %s * %s + vec4(-0.6666, 0, 0.8333, 0.1666);\n", t, t, s); + GLSLF("%s.xy *= vec2(1, 1) / vec2(%s.z, %s.w);\n", t, t, t); + GLSLF("%s.xy += vec2(1.0 + %s, 1.0 - %s);\n", t, s, s); +} + +void pass_sample_bicubic_fast(struct gl_shader_cache *sc) +{ + GLSLF("{\n"); + GLSL(vec2 fcoord = fract(pos * size + vec2(0.5, 0.5));) + bicubic_calcweights(sc, "parmx", "fcoord.x"); + bicubic_calcweights(sc, "parmy", "fcoord.y"); + GLSL(vec4 cdelta;) + GLSL(cdelta.xz = parmx.rg * vec2(-pt.x, pt.x);) + GLSL(cdelta.yw = parmy.rg * vec2(-pt.y, pt.y);) + // first y-interpolation + GLSL(vec4 ar = texture(tex, pos + cdelta.xy);) + GLSL(vec4 ag = texture(tex, pos + cdelta.xw);) + GLSL(vec4 ab = mix(ag, ar, parmy.b);) + // second y-interpolation + GLSL(vec4 br = texture(tex, pos + cdelta.zy);) + GLSL(vec4 bg = texture(tex, pos + cdelta.zw);) + GLSL(vec4 aa = mix(bg, br, parmy.b);) + // x-interpolation + GLSL(color = mix(aa, ab, parmx.b);) + GLSLF("}\n"); +} + +void pass_sample_oversample(struct gl_shader_cache *sc, struct scaler *scaler, + int w, int h) +{ + GLSLF("{\n"); + GLSL(vec2 pos = pos - vec2(0.5) * pt;) // round to nearest + GLSL(vec2 fcoord = fract(pos * size - vec2(0.5));) + // Determine the mixing coefficient vector + gl_sc_uniform_vec2(sc, "output_size", (float[2]){w, h}); + GLSL(vec2 coeff = fcoord * output_size/size;) + float threshold = scaler->conf.kernel.params[0]; + threshold = isnan(threshold) ? 0.0 : threshold; + GLSLF("coeff = (coeff - %f) * 1.0/%f;\n", threshold, 1.0 - 2 * threshold); + GLSL(coeff = clamp(coeff, 0.0, 1.0);) + // Compute the right blend of colors + GLSL(color = texture(tex, pos + pt * (coeff - fcoord));) + GLSLF("}\n"); +} + +// Common constants for SMPTE ST.2084 (HDR) +static const float PQ_M1 = 2610./4096 * 1./4, + PQ_M2 = 2523./4096 * 128, + PQ_C1 = 3424./4096, + PQ_C2 = 2413./4096 * 32, + PQ_C3 = 2392./4096 * 32; + +// Common constants for ARIB STD-B67 (HLG) +static const float HLG_A = 0.17883277, + HLG_B = 0.28466892, + HLG_C = 0.55991073; + +// Common constants for Panasonic V-Log +static const float VLOG_B = 0.00873, + VLOG_C = 0.241514, + VLOG_D = 0.598206; + +// Common constants for Sony S-Log +static const float SLOG_A = 0.432699, + SLOG_B = 0.037584, + SLOG_C = 0.616596 + 0.03, + SLOG_P = 3.538813, + SLOG_Q = 0.030001, + SLOG_K2 = 155.0 / 219.0; + +// Linearize (expand), given a TRC as input. In essence, this is the ITU-R +// EOTF, calculated on an idealized (reference) monitor with a white point of +// MP_REF_WHITE and infinite contrast. +// +// These functions always output to a normalized scale of [0,1], for +// convenience of the video.c code that calls it. To get the values in an +// absolute scale, multiply the result by `mp_trc_nom_peak(trc)` +void pass_linearize(struct gl_shader_cache *sc, enum mp_csp_trc trc) +{ + if (trc == MP_CSP_TRC_LINEAR) + return; + + GLSLF("// linearize\n"); + + // Note that this clamp may technically violate the definition of + // ITU-R BT.2100, which allows for sub-blacks and super-whites to be + // displayed on the display where such would be possible. That said, the + // problem is that not all gamma curves are well-defined on the values + // outside this range, so we ignore it and just clip anyway for sanity. + GLSL(color.rgb = clamp(color.rgb, 0.0, 1.0);) + + switch (trc) { + case MP_CSP_TRC_SRGB: + GLSLF("color.rgb = mix(color.rgb * vec3(1.0/12.92), \n" + " pow((color.rgb + vec3(0.055))/vec3(1.055), vec3(2.4)), \n" + " %s(lessThan(vec3(0.04045), color.rgb))); \n", + gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_BT_1886: + GLSL(color.rgb = pow(color.rgb, vec3(2.4));) + break; + case MP_CSP_TRC_GAMMA18: + GLSL(color.rgb = pow(color.rgb, vec3(1.8));) + break; + case MP_CSP_TRC_GAMMA20: + GLSL(color.rgb = pow(color.rgb, vec3(2.0));) + break; + case MP_CSP_TRC_GAMMA22: + GLSL(color.rgb = pow(color.rgb, vec3(2.2));) + break; + case MP_CSP_TRC_GAMMA24: + GLSL(color.rgb = pow(color.rgb, vec3(2.4));) + break; + case MP_CSP_TRC_GAMMA26: + GLSL(color.rgb = pow(color.rgb, vec3(2.6));) + break; + case MP_CSP_TRC_GAMMA28: + GLSL(color.rgb = pow(color.rgb, vec3(2.8));) + break; + case MP_CSP_TRC_PRO_PHOTO: + GLSLF("color.rgb = mix(color.rgb * vec3(1.0/16.0), \n" + " pow(color.rgb, vec3(1.8)), \n" + " %s(lessThan(vec3(0.03125), color.rgb))); \n", + gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_PQ: + GLSLF("color.rgb = pow(color.rgb, vec3(1.0/%f));\n", PQ_M2); + GLSLF("color.rgb = max(color.rgb - vec3(%f), vec3(0.0)) \n" + " / (vec3(%f) - vec3(%f) * color.rgb);\n", + PQ_C1, PQ_C2, PQ_C3); + GLSLF("color.rgb = pow(color.rgb, vec3(%f));\n", 1.0 / PQ_M1); + // PQ's output range is 0-10000, but we need it to be relative to + // MP_REF_WHITE instead, so rescale + GLSLF("color.rgb *= vec3(%f);\n", 10000 / MP_REF_WHITE); + break; + case MP_CSP_TRC_HLG: + GLSLF("color.rgb = mix(vec3(4.0) * color.rgb * color.rgb,\n" + " exp((color.rgb - vec3(%f)) * vec3(1.0/%f)) + vec3(%f),\n" + " %s(lessThan(vec3(0.5), color.rgb)));\n", + HLG_C, HLG_A, HLG_B, gl_sc_bvec(sc, 3)); + GLSLF("color.rgb *= vec3(1.0/%f);\n", MP_REF_WHITE_HLG); + break; + case MP_CSP_TRC_V_LOG: + GLSLF("color.rgb = mix((color.rgb - vec3(0.125)) * vec3(1.0/5.6), \n" + " pow(vec3(10.0), (color.rgb - vec3(%f)) * vec3(1.0/%f)) \n" + " - vec3(%f), \n" + " %s(lessThanEqual(vec3(0.181), color.rgb))); \n", + VLOG_D, VLOG_C, VLOG_B, gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_S_LOG1: + GLSLF("color.rgb = pow(vec3(10.0), (color.rgb - vec3(%f)) * vec3(1.0/%f))\n" + " - vec3(%f);\n", + SLOG_C, SLOG_A, SLOG_B); + break; + case MP_CSP_TRC_S_LOG2: + GLSLF("color.rgb = mix((color.rgb - vec3(%f)) * vec3(1.0/%f), \n" + " (pow(vec3(10.0), (color.rgb - vec3(%f)) * vec3(1.0/%f)) \n" + " - vec3(%f)) * vec3(1.0/%f), \n" + " %s(lessThanEqual(vec3(%f), color.rgb))); \n", + SLOG_Q, SLOG_P, SLOG_C, SLOG_A, SLOG_B, SLOG_K2, gl_sc_bvec(sc, 3), SLOG_Q); + break; + case MP_CSP_TRC_ST428: + GLSL(color.rgb = vec3(52.37/48.0) * pow(color.rgb, vec3(2.6));); + break; + default: + abort(); + } + + // Rescale to prevent clipping on non-float textures + GLSLF("color.rgb *= vec3(1.0/%f);\n", mp_trc_nom_peak(trc)); +} + +// Delinearize (compress), given a TRC as output. This corresponds to the +// inverse EOTF (not the OETF) in ITU-R terminology, again assuming a +// reference monitor. +// +// Like pass_linearize, this functions ingests values on an normalized scale +void pass_delinearize(struct gl_shader_cache *sc, enum mp_csp_trc trc) +{ + if (trc == MP_CSP_TRC_LINEAR) + return; + + GLSLF("// delinearize\n"); + GLSL(color.rgb = clamp(color.rgb, 0.0, 1.0);) + GLSLF("color.rgb *= vec3(%f);\n", mp_trc_nom_peak(trc)); + + switch (trc) { + case MP_CSP_TRC_SRGB: + GLSLF("color.rgb = mix(color.rgb * vec3(12.92), \n" + " vec3(1.055) * pow(color.rgb, vec3(1.0/2.4)) \n" + " - vec3(0.055), \n" + " %s(lessThanEqual(vec3(0.0031308), color.rgb))); \n", + gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_BT_1886: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/2.4));) + break; + case MP_CSP_TRC_GAMMA18: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/1.8));) + break; + case MP_CSP_TRC_GAMMA20: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/2.0));) + break; + case MP_CSP_TRC_GAMMA22: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/2.2));) + break; + case MP_CSP_TRC_GAMMA24: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/2.4));) + break; + case MP_CSP_TRC_GAMMA26: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/2.6));) + break; + case MP_CSP_TRC_GAMMA28: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/2.8));) + break; + case MP_CSP_TRC_PRO_PHOTO: + GLSLF("color.rgb = mix(color.rgb * vec3(16.0), \n" + " pow(color.rgb, vec3(1.0/1.8)), \n" + " %s(lessThanEqual(vec3(0.001953), color.rgb))); \n", + gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_PQ: + GLSLF("color.rgb *= vec3(1.0/%f);\n", 10000 / MP_REF_WHITE); + GLSLF("color.rgb = pow(color.rgb, vec3(%f));\n", PQ_M1); + GLSLF("color.rgb = (vec3(%f) + vec3(%f) * color.rgb) \n" + " / (vec3(1.0) + vec3(%f) * color.rgb);\n", + PQ_C1, PQ_C2, PQ_C3); + GLSLF("color.rgb = pow(color.rgb, vec3(%f));\n", PQ_M2); + break; + case MP_CSP_TRC_HLG: + GLSLF("color.rgb *= vec3(%f);\n", MP_REF_WHITE_HLG); + GLSLF("color.rgb = mix(vec3(0.5) * sqrt(color.rgb),\n" + " vec3(%f) * log(color.rgb - vec3(%f)) + vec3(%f),\n" + " %s(lessThan(vec3(1.0), color.rgb)));\n", + HLG_A, HLG_B, HLG_C, gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_V_LOG: + GLSLF("color.rgb = mix(vec3(5.6) * color.rgb + vec3(0.125), \n" + " vec3(%f) * log(color.rgb + vec3(%f)) \n" + " + vec3(%f), \n" + " %s(lessThanEqual(vec3(0.01), color.rgb))); \n", + VLOG_C / M_LN10, VLOG_B, VLOG_D, gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_S_LOG1: + GLSLF("color.rgb = vec3(%f) * log(color.rgb + vec3(%f)) + vec3(%f);\n", + SLOG_A / M_LN10, SLOG_B, SLOG_C); + break; + case MP_CSP_TRC_S_LOG2: + GLSLF("color.rgb = mix(vec3(%f) * color.rgb + vec3(%f), \n" + " vec3(%f) * log(vec3(%f) * color.rgb + vec3(%f)) \n" + " + vec3(%f), \n" + " %s(lessThanEqual(vec3(0.0), color.rgb))); \n", + SLOG_P, SLOG_Q, SLOG_A / M_LN10, SLOG_K2, SLOG_B, SLOG_C, gl_sc_bvec(sc, 3)); + break; + case MP_CSP_TRC_ST428: + GLSL(color.rgb = pow(color.rgb * vec3(48.0/52.37), vec3(1.0/2.6));); + break; + default: + abort(); + } +} + +// Apply the OOTF mapping from a given light type to display-referred light. +// Assumes absolute scale values. `peak` is used to tune the OOTF where +// applicable (currently only HLG). +static void pass_ootf(struct gl_shader_cache *sc, enum mp_csp_light light, + float peak) +{ + if (light == MP_CSP_LIGHT_DISPLAY) + return; + + GLSLF("// apply ootf\n"); + + switch (light) + { + case MP_CSP_LIGHT_SCENE_HLG: { + // HLG OOTF from BT.2100, scaled to the chosen display peak + float gamma = MPMAX(1.0, 1.2 + 0.42 * log10(peak * MP_REF_WHITE / 1000.0)); + GLSLF("color.rgb *= vec3(%f * pow(dot(src_luma, color.rgb), %f));\n", + peak / pow(12.0 / MP_REF_WHITE_HLG, gamma), gamma - 1.0); + break; + } + case MP_CSP_LIGHT_SCENE_709_1886: + // This OOTF is defined by encoding the result as 709 and then decoding + // it as 1886; although this is called 709_1886 we actually use the + // more precise (by one decimal) values from BT.2020 instead + GLSLF("color.rgb = mix(color.rgb * vec3(4.5), \n" + " vec3(1.0993) * pow(color.rgb, vec3(0.45)) - vec3(0.0993), \n" + " %s(lessThan(vec3(0.0181), color.rgb))); \n", + gl_sc_bvec(sc, 3)); + GLSL(color.rgb = pow(color.rgb, vec3(2.4));) + break; + case MP_CSP_LIGHT_SCENE_1_2: + GLSL(color.rgb = pow(color.rgb, vec3(1.2));) + break; + default: + abort(); + } +} + +// Inverse of the function pass_ootf, for completeness' sake. +static void pass_inverse_ootf(struct gl_shader_cache *sc, enum mp_csp_light light, + float peak) +{ + if (light == MP_CSP_LIGHT_DISPLAY) + return; + + GLSLF("// apply inverse ootf\n"); + + switch (light) + { + case MP_CSP_LIGHT_SCENE_HLG: { + float gamma = MPMAX(1.0, 1.2 + 0.42 * log10(peak * MP_REF_WHITE / 1000.0)); + GLSLF("color.rgb *= vec3(1.0/%f);\n", peak / pow(12.0 / MP_REF_WHITE_HLG, gamma)); + GLSLF("color.rgb /= vec3(max(1e-6, pow(dot(src_luma, color.rgb), %f)));\n", + (gamma - 1.0) / gamma); + break; + } + case MP_CSP_LIGHT_SCENE_709_1886: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/2.4));) + GLSLF("color.rgb = mix(color.rgb * vec3(1.0/4.5), \n" + " pow((color.rgb + vec3(0.0993)) * vec3(1.0/1.0993), \n" + " vec3(1/0.45)), \n" + " %s(lessThan(vec3(0.08145), color.rgb))); \n", + gl_sc_bvec(sc, 3)); + break; + case MP_CSP_LIGHT_SCENE_1_2: + GLSL(color.rgb = pow(color.rgb, vec3(1.0/1.2));) + break; + default: + abort(); + } +} + +// Average light level for SDR signals. This is equal to a signal level of 0.5 +// under a typical presentation gamma of about 2.0. +static const float sdr_avg = 0.25; + +static void hdr_update_peak(struct gl_shader_cache *sc, + const struct gl_tone_map_opts *opts) +{ + // Update the sig_peak/sig_avg from the old SSBO state + GLSL(if (average.y > 0.0) {) + GLSL( sig_avg = max(1e-3, average.x);) + GLSL( sig_peak = max(1.00, average.y);) + GLSL(}) + + // Chosen to avoid overflowing on an 8K buffer + const float log_min = 1e-3, log_scale = 400.0, sig_scale = 10000.0; + + // For performance, and to avoid overflows, we tally up the sub-results per + // pixel using shared memory first + GLSLH(shared int wg_sum;) + GLSLH(shared uint wg_max;) + GLSL(wg_sum = 0; wg_max = 0u;) + GLSL(barrier();) + GLSLF("float sig_log = log(max(sig_max, %f));\n", log_min); + GLSLF("atomicAdd(wg_sum, int(sig_log * %f));\n", log_scale); + GLSLF("atomicMax(wg_max, uint(sig_max * %f));\n", sig_scale); + + // Have one thread per work group update the global atomics + GLSL(memoryBarrierShared();) + GLSL(barrier();) + GLSL(if (gl_LocalInvocationIndex == 0u) {) + GLSL( int wg_avg = wg_sum / int(gl_WorkGroupSize.x * gl_WorkGroupSize.y);) + GLSL( atomicAdd(frame_sum, wg_avg);) + GLSL( atomicMax(frame_max, wg_max);) + GLSL( memoryBarrierBuffer();) + GLSL(}) + GLSL(barrier();) + + // Finally, to update the global state, we increment a counter per dispatch + GLSL(uint num_wg = gl_NumWorkGroups.x * gl_NumWorkGroups.y;) + GLSL(if (gl_LocalInvocationIndex == 0u && atomicAdd(counter, 1u) == num_wg - 1u) {) + GLSL( counter = 0u;) + GLSL( vec2 cur = vec2(float(frame_sum) / float(num_wg), frame_max);) + GLSLF(" cur *= vec2(1.0/%f, 1.0/%f);\n", log_scale, sig_scale); + GLSL( cur.x = exp(cur.x);) + GLSL( if (average.y == 0.0)) + GLSL( average = cur;) + + // Use an IIR low-pass filter to smooth out the detected values, with a + // configurable decay rate based on the desired time constant (tau) + if (opts->decay_rate) { + float decay = 1.0f - expf(-1.0f / opts->decay_rate); + GLSLF(" average += %f * (cur - average);\n", decay); + } else { + GLSLF(" average = cur;\n"); + } + + // Scene change hysteresis + float log_db = 10.0 / log(10.0); + GLSLF(" float weight = smoothstep(%f, %f, abs(log(cur.x / average.x)));\n", + opts->scene_threshold_low / log_db, + opts->scene_threshold_high / log_db); + GLSL( average = mix(average, cur, weight);) + + // Reset SSBO state for the next frame + GLSL( frame_sum = 0; frame_max = 0u;) + GLSL( memoryBarrierBuffer();) + GLSL(}) +} + +static inline float pq_delinearize(float x) +{ + x *= MP_REF_WHITE / 10000.0; + x = powf(x, PQ_M1); + x = (PQ_C1 + PQ_C2 * x) / (1.0 + PQ_C3 * x); + x = pow(x, PQ_M2); + return x; +} + +// Tone map from a known peak brightness to the range [0,1]. If ref_peak +// is 0, we will use peak detection instead +static void pass_tone_map(struct gl_shader_cache *sc, + float src_peak, float dst_peak, + const struct gl_tone_map_opts *opts) +{ + GLSLF("// HDR tone mapping\n"); + + // To prevent discoloration due to out-of-bounds clipping, we need to make + // sure to reduce the value range as far as necessary to keep the entire + // signal in range, so tone map based on the brightest component. + GLSL(int sig_idx = 0;) + GLSL(if (color[1] > color[sig_idx]) sig_idx = 1;) + GLSL(if (color[2] > color[sig_idx]) sig_idx = 2;) + GLSL(float sig_max = color[sig_idx];) + GLSLF("float sig_peak = %f;\n", src_peak); + GLSLF("float sig_avg = %f;\n", sdr_avg); + + if (opts->compute_peak >= 0) + hdr_update_peak(sc, opts); + + // Always hard-clip the upper bound of the signal range to avoid functions + // exploding on inputs greater than 1.0 + GLSLF("vec3 sig = min(color.rgb, sig_peak);\n"); + + // This function always operates on an absolute scale, so ignore the + // dst_peak normalization for it + float dst_scale = dst_peak; + enum tone_mapping curve = opts->curve ? opts->curve : TONE_MAPPING_BT_2390; + if (curve == TONE_MAPPING_BT_2390) + dst_scale = 1.0; + + // Rescale the variables in order to bring it into a representation where + // 1.0 represents the dst_peak. This is because all of the tone mapping + // algorithms are defined in such a way that they map to the range [0.0, 1.0]. + if (dst_scale > 1.0) { + GLSLF("sig *= 1.0/%f;\n", dst_scale); + GLSLF("sig_peak *= 1.0/%f;\n", dst_scale); + } + + GLSL(float sig_orig = sig[sig_idx];) + GLSLF("float slope = min(%f, %f / sig_avg);\n", opts->max_boost, sdr_avg); + GLSL(sig *= slope;) + GLSL(sig_peak *= slope;) + + float param = opts->curve_param; + switch (curve) { + case TONE_MAPPING_CLIP: + GLSLF("sig = min(%f * sig, 1.0);\n", isnan(param) ? 1.0 : param); + break; + + case TONE_MAPPING_MOBIUS: + GLSLF("if (sig_peak > (1.0 + 1e-6)) {\n"); + GLSLF("const float j = %f;\n", isnan(param) ? 0.3 : param); + // solve for M(j) = j; M(sig_peak) = 1.0; M'(j) = 1.0 + // where M(x) = scale * (x+a)/(x+b) + GLSLF("float a = -j*j * (sig_peak - 1.0) / (j*j - 2.0*j + sig_peak);\n"); + GLSLF("float b = (j*j - 2.0*j*sig_peak + sig_peak) / " + "max(1e-6, sig_peak - 1.0);\n"); + GLSLF("float scale = (b*b + 2.0*b*j + j*j) / (b-a);\n"); + GLSLF("sig = mix(sig, scale * (sig + vec3(a)) / (sig + vec3(b))," + " %s(greaterThan(sig, vec3(j))));\n", + gl_sc_bvec(sc, 3)); + GLSLF("}\n"); + break; + + case TONE_MAPPING_REINHARD: { + float contrast = isnan(param) ? 0.5 : param, + offset = (1.0 - contrast) / contrast; + GLSLF("sig = sig / (sig + vec3(%f));\n", offset); + GLSLF("float scale = (sig_peak + %f) / sig_peak;\n", offset); + GLSL(sig *= scale;) + break; + } + + case TONE_MAPPING_HABLE: { + float A = 0.15, B = 0.50, C = 0.10, D = 0.20, E = 0.02, F = 0.30; + GLSLHF("vec3 hable(vec3 x) {\n"); + GLSLHF("return (x * (%f*x + vec3(%f)) + vec3(%f)) / " + " (x * (%f*x + vec3(%f)) + vec3(%f)) " + " - vec3(%f);\n", + A, C*B, D*E, + A, B, D*F, + E/F); + GLSLHF("}\n"); + GLSLF("sig = hable(max(vec3(0.0), sig)) / hable(vec3(sig_peak)).x;\n"); + break; + } + + case TONE_MAPPING_GAMMA: { + float gamma = isnan(param) ? 1.8 : param; + GLSLF("const float cutoff = 0.05, gamma = 1.0/%f;\n", gamma); + GLSL(float scale = pow(cutoff / sig_peak, gamma.x) / cutoff;) + GLSLF("sig = mix(scale * sig," + " pow(sig / sig_peak, vec3(gamma))," + " %s(greaterThan(sig, vec3(cutoff))));\n", + gl_sc_bvec(sc, 3)); + break; + } + + case TONE_MAPPING_LINEAR: { + float coeff = isnan(param) ? 1.0 : param; + GLSLF("sig = min(%f / sig_peak, 1.0) * sig;\n", coeff); + break; + } + + case TONE_MAPPING_BT_2390: + // We first need to encode both sig and sig_peak into PQ space + GLSLF("vec4 sig_pq = vec4(sig.rgb, sig_peak); \n" + "sig_pq *= vec4(1.0/%f); \n" + "sig_pq = pow(sig_pq, vec4(%f)); \n" + "sig_pq = (vec4(%f) + vec4(%f) * sig_pq) \n" + " / (vec4(1.0) + vec4(%f) * sig_pq); \n" + "sig_pq = pow(sig_pq, vec4(%f)); \n", + 10000.0 / MP_REF_WHITE, PQ_M1, PQ_C1, PQ_C2, PQ_C3, PQ_M2); + // Encode both the signal and the target brightness to be relative to + // the source peak brightness, and figure out the target peak in this space + GLSLF("float scale = 1.0 / sig_pq.a; \n" + "sig_pq.rgb *= vec3(scale); \n" + "float maxLum = %f * scale; \n", + pq_delinearize(dst_peak)); + // Apply piece-wise hermite spline + GLSLF("float ks = 1.5 * maxLum - 0.5; \n" + "vec3 tb = (sig_pq.rgb - vec3(ks)) / vec3(1.0 - ks); \n" + "vec3 tb2 = tb * tb; \n" + "vec3 tb3 = tb2 * tb; \n" + "vec3 pb = (2.0 * tb3 - 3.0 * tb2 + vec3(1.0)) * vec3(ks) + \n" + " (tb3 - 2.0 * tb2 + tb) * vec3(1.0 - ks) + \n" + " (-2.0 * tb3 + 3.0 * tb2) * vec3(maxLum); \n" + "sig = mix(pb, sig_pq.rgb, %s(lessThan(sig_pq.rgb, vec3(ks)))); \n", + gl_sc_bvec(sc, 3)); + // Convert back from PQ space to linear light + GLSLF("sig *= vec3(sig_pq.a); \n" + "sig = pow(sig, vec3(1.0/%f)); \n" + "sig = max(sig - vec3(%f), 0.0) / \n" + " (vec3(%f) - vec3(%f) * sig); \n" + "sig = pow(sig, vec3(1.0/%f)); \n" + "sig *= vec3(%f); \n", + PQ_M2, PQ_C1, PQ_C2, PQ_C3, PQ_M1, 10000.0 / MP_REF_WHITE); + break; + + default: + abort(); + } + + GLSLF("float coeff = max(sig[sig_idx] - %f, 1e-6) / \n" + " max(sig[sig_idx], 1.0); \n" + "coeff = %f * pow(coeff / %f, %f); \n" + "color.rgb *= sig[sig_idx] / sig_orig; \n" + "color.rgb = mix(color.rgb, %f * sig, coeff); \n", + 0.18 / dst_scale, 0.90, dst_scale, 0.20, dst_scale); +} + +// Map colors from one source space to another. These source spaces must be +// known (i.e. not MP_CSP_*_AUTO), as this function won't perform any +// auto-guessing. If is_linear is true, we assume the input has already been +// linearized (e.g. for linear-scaling). If `opts->compute_peak` is true, we +// will detect the peak instead of relying on metadata. Note that this requires +// the caller to have already bound the appropriate SSBO and set up the compute +// shader metadata +void pass_color_map(struct gl_shader_cache *sc, bool is_linear, + struct mp_colorspace src, struct mp_colorspace dst, + const struct gl_tone_map_opts *opts) +{ + GLSLF("// color mapping\n"); + + // Some operations need access to the video's luma coefficients, so make + // them available + float rgb2xyz[3][3]; + mp_get_rgb2xyz_matrix(mp_get_csp_primaries(src.primaries), rgb2xyz); + gl_sc_uniform_vec3(sc, "src_luma", rgb2xyz[1]); + mp_get_rgb2xyz_matrix(mp_get_csp_primaries(dst.primaries), rgb2xyz); + gl_sc_uniform_vec3(sc, "dst_luma", rgb2xyz[1]); + + bool need_ootf = src.light != dst.light; + if (src.light == MP_CSP_LIGHT_SCENE_HLG && src.hdr.max_luma != dst.hdr.max_luma) + need_ootf = true; + + // All operations from here on require linear light as a starting point, + // so we linearize even if src.gamma == dst.gamma when one of the other + // operations needs it + bool need_linear = src.gamma != dst.gamma || + src.primaries != dst.primaries || + src.hdr.max_luma != dst.hdr.max_luma || + need_ootf; + + if (need_linear && !is_linear) { + // We also pull it up so that 1.0 is the reference white + pass_linearize(sc, src.gamma); + is_linear = true; + } + + // Pre-scale the incoming values into an absolute scale + GLSLF("color.rgb *= vec3(%f);\n", mp_trc_nom_peak(src.gamma)); + + if (need_ootf) + pass_ootf(sc, src.light, src.hdr.max_luma / MP_REF_WHITE); + + // Tone map to prevent clipping due to excessive brightness + if (src.hdr.max_luma > dst.hdr.max_luma) { + pass_tone_map(sc, src.hdr.max_luma / MP_REF_WHITE, + dst.hdr.max_luma / MP_REF_WHITE, opts); + } + + // Adapt to the right colorspace if necessary + if (src.primaries != dst.primaries) { + struct mp_csp_primaries csp_src = mp_get_csp_primaries(src.primaries), + csp_dst = mp_get_csp_primaries(dst.primaries); + float m[3][3] = {{0}}; + mp_get_cms_matrix(csp_src, csp_dst, MP_INTENT_RELATIVE_COLORIMETRIC, m); + gl_sc_uniform_mat3(sc, "cms_matrix", true, &m[0][0]); + GLSL(color.rgb = cms_matrix * color.rgb;) + + if (!opts->gamut_mode || opts->gamut_mode == GAMUT_DESATURATE) { + GLSL(float cmin = min(min(color.r, color.g), color.b);) + GLSL(if (cmin < 0.0) { + float luma = dot(dst_luma, color.rgb); + float coeff = cmin / (cmin - luma); + color.rgb = mix(color.rgb, vec3(luma), coeff); + }) + GLSLF("float cmax = 1.0/%f * max(max(color.r, color.g), color.b);\n", + dst.hdr.max_luma / MP_REF_WHITE); + GLSL(if (cmax > 1.0) color.rgb /= cmax;) + } + } + + if (need_ootf) + pass_inverse_ootf(sc, dst.light, dst.hdr.max_luma / MP_REF_WHITE); + + // Post-scale the outgoing values from absolute scale to normalized. + // For SDR, we normalize to the chosen signal peak. For HDR, we normalize + // to the encoding range of the transfer function. + float dst_range = dst.hdr.max_luma / MP_REF_WHITE; + if (mp_trc_is_hdr(dst.gamma)) + dst_range = mp_trc_nom_peak(dst.gamma); + + GLSLF("color.rgb *= vec3(%f);\n", 1.0 / dst_range); + + // Warn for remaining out-of-gamut colors if enabled + if (opts->gamut_mode == GAMUT_WARN) { + GLSL(if (any(greaterThan(color.rgb, vec3(1.005))) || + any(lessThan(color.rgb, vec3(-0.005))))) + GLSL(color.rgb = vec3(1.0) - color.rgb;) // invert + } + + if (is_linear) + pass_delinearize(sc, dst.gamma); +} + +// Wide usage friendly PRNG, shamelessly stolen from a GLSL tricks forum post. +// Obtain random numbers by calling rand(h), followed by h = permute(h) to +// update the state. Assumes the texture was hooked. +// permute() was modified from the original to avoid "large" numbers in +// calculations, since low-end mobile GPUs choke on them (overflow). +static void prng_init(struct gl_shader_cache *sc, AVLFG *lfg) +{ + GLSLH(float mod289(float x) { return x - floor(x * 1.0/289.0) * 289.0; }) + GLSLHF("float permute(float x) {\n"); + GLSLH(return mod289( mod289(34.0*x + 1.0) * (fract(x) + 1.0) );) + GLSLHF("}\n"); + GLSLH(float rand(float x) { return fract(x * 1.0/41.0); }) + + // Initialize the PRNG by hashing the position + a random uniform + GLSL(vec3 _m = vec3(HOOKED_pos, random) + vec3(1.0);) + GLSL(float h = permute(permute(permute(_m.x)+_m.y)+_m.z);) + gl_sc_uniform_dynamic(sc); + gl_sc_uniform_f(sc, "random", (double)av_lfg_get(lfg) / UINT32_MAX); +} + +const struct deband_opts deband_opts_def = { + .iterations = 1, + .threshold = 48.0, + .range = 16.0, + .grain = 32.0, +}; + +#define OPT_BASE_STRUCT struct deband_opts +const struct m_sub_options deband_conf = { + .opts = (const m_option_t[]) { + {"iterations", OPT_INT(iterations), M_RANGE(0, 16)}, + {"threshold", OPT_FLOAT(threshold), M_RANGE(0.0, 4096.0)}, + {"range", OPT_FLOAT(range), M_RANGE(1.0, 64.0)}, + {"grain", OPT_FLOAT(grain), M_RANGE(0.0, 4096.0)}, + {0} + }, + .size = sizeof(struct deband_opts), + .defaults = &deband_opts_def, +}; + +// Stochastically sample a debanded result from a hooked texture. +void pass_sample_deband(struct gl_shader_cache *sc, struct deband_opts *opts, + AVLFG *lfg, enum mp_csp_trc trc) +{ + // Initialize the PRNG + GLSLF("{\n"); + prng_init(sc, lfg); + + // Helper: Compute a stochastic approximation of the avg color around a + // pixel + GLSLHF("vec4 average(float range, inout float h) {\n"); + // Compute a random rangle and distance + GLSLH(float dist = rand(h) * range; h = permute(h);) + GLSLH(float dir = rand(h) * 6.2831853; h = permute(h);) + GLSLH(vec2 o = dist * vec2(cos(dir), sin(dir));) + + // Sample at quarter-turn intervals around the source pixel + GLSLH(vec4 ref[4];) + GLSLH(ref[0] = HOOKED_texOff(vec2( o.x, o.y));) + GLSLH(ref[1] = HOOKED_texOff(vec2(-o.y, o.x));) + GLSLH(ref[2] = HOOKED_texOff(vec2(-o.x, -o.y));) + GLSLH(ref[3] = HOOKED_texOff(vec2( o.y, -o.x));) + + // Return the (normalized) average + GLSLH(return (ref[0] + ref[1] + ref[2] + ref[3])*0.25;) + GLSLHF("}\n"); + + // Sample the source pixel + GLSL(color = HOOKED_tex(HOOKED_pos);) + GLSLF("vec4 avg, diff;\n"); + for (int i = 1; i <= opts->iterations; i++) { + // Sample the average pixel and use it instead of the original if + // the difference is below the given threshold + GLSLF("avg = average(%f, h);\n", i * opts->range); + GLSL(diff = abs(color - avg);) + GLSLF("color = mix(avg, color, %s(greaterThan(diff, vec4(%f))));\n", + gl_sc_bvec(sc, 4), opts->threshold / (i * 16384.0)); + } + + // Add some random noise to smooth out residual differences + GLSL(vec3 noise;) + GLSL(noise.x = rand(h); h = permute(h);) + GLSL(noise.y = rand(h); h = permute(h);) + GLSL(noise.z = rand(h); h = permute(h);) + + // Noise is scaled to the signal level to prevent extreme noise for HDR + float gain = opts->grain/8192.0 / mp_trc_nom_peak(trc); + GLSLF("color.xyz += %f * (noise - vec3(0.5));\n", gain); + GLSLF("}\n"); +} + +// Assumes the texture was hooked +void pass_sample_unsharp(struct gl_shader_cache *sc, float param) { + GLSLF("{\n"); + GLSL(float st1 = 1.2;) + GLSL(vec4 p = HOOKED_tex(HOOKED_pos);) + GLSL(vec4 sum1 = HOOKED_texOff(st1 * vec2(+1, +1)) + + HOOKED_texOff(st1 * vec2(+1, -1)) + + HOOKED_texOff(st1 * vec2(-1, +1)) + + HOOKED_texOff(st1 * vec2(-1, -1));) + GLSL(float st2 = 1.5;) + GLSL(vec4 sum2 = HOOKED_texOff(st2 * vec2(+1, 0)) + + HOOKED_texOff(st2 * vec2( 0, +1)) + + HOOKED_texOff(st2 * vec2(-1, 0)) + + HOOKED_texOff(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"); +} |