6 #include <SDL2/SDL_error.h>
7 #include <SDL2/SDL_events.h>
8 #include <SDL2/SDL_image.h>
9 #include <SDL2/SDL_keyboard.h>
10 #include <SDL2/SDL_mouse.h>
11 #include <SDL2/SDL_video.h>
19 #include "gpu_timers.h"
29 #define BUFFER_OFFSET(i) ((char *)nullptr + (i))
35 // Operating point 3 (10 Hz on CPU, excluding preprocessing).
36 constexpr float patch_overlap_ratio = 0.75f;
37 constexpr unsigned coarsest_level = 5;
38 constexpr unsigned finest_level = 1;
39 constexpr unsigned patch_size_pixels = 12;
41 // Weighting constants for the different parts of the variational refinement.
42 // These don't correspond 1:1 to the values given in the DIS paper,
43 // since we have different normalizations and ranges in some cases.
44 // These are found through a simple grid search on some MPI-Sintel data,
45 // although the error (EPE) seems to be fairly insensitive to the precise values.
46 // Only the relative values matter, so we fix alpha (the smoothness constant)
47 // at unity and tweak the others.
48 float vr_alpha = 1.0f, vr_delta = 0.25f, vr_gamma = 0.25f;
50 bool enable_timing = true;
51 bool detailed_timing = false;
52 bool enable_warmup = false;
53 bool in_warmup = false;
54 bool enable_variational_refinement = true; // Just for debugging.
55 bool enable_interpolation = false;
57 // Some global OpenGL objects.
58 // TODO: These should really be part of DISComputeFlow.
59 GLuint nearest_sampler, linear_sampler, zero_border_sampler;
62 // Structures for asynchronous readback. We assume everything is the same size (and GL_RG16F).
63 struct ReadInProgress {
65 string filename0, filename1;
66 string flow_filename, ppm_filename; // Either may be empty for no write.
68 stack<GLuint> spare_pbos;
69 deque<ReadInProgress> reads_in_progress;
71 int find_num_levels(int width, int height)
74 for (int w = width, h = height; w > 1 || h > 1; ) {
82 string read_file(const string &filename)
84 FILE *fp = fopen(filename.c_str(), "r");
86 perror(filename.c_str());
90 int ret = fseek(fp, 0, SEEK_END);
92 perror("fseek(SEEK_END)");
98 ret = fseek(fp, 0, SEEK_SET);
100 perror("fseek(SEEK_SET)");
106 ret = fread(&str[0], size, 1, fp);
112 fprintf(stderr, "Short read when trying to read %d bytes from %s\n",
113 size, filename.c_str());
122 GLuint compile_shader(const string &shader_src, GLenum type)
124 GLuint obj = glCreateShader(type);
125 const GLchar* source[] = { shader_src.data() };
126 const GLint length[] = { (GLint)shader_src.size() };
127 glShaderSource(obj, 1, source, length);
128 glCompileShader(obj);
130 GLchar info_log[4096];
131 GLsizei log_length = sizeof(info_log) - 1;
132 glGetShaderInfoLog(obj, log_length, &log_length, info_log);
133 info_log[log_length] = 0;
134 if (strlen(info_log) > 0) {
135 fprintf(stderr, "Shader compile log: %s\n", info_log);
139 glGetShaderiv(obj, GL_COMPILE_STATUS, &status);
140 if (status == GL_FALSE) {
141 // Add some line numbers to easier identify compile errors.
142 string src_with_lines = "/* 1 */ ";
144 for (char ch : shader_src) {
145 src_with_lines.push_back(ch);
148 snprintf(buf, sizeof(buf), "/* %3zu */ ", ++lineno);
149 src_with_lines += buf;
153 fprintf(stderr, "Failed to compile shader:\n%s\n", src_with_lines.c_str());
165 GLuint load_texture(const char *filename, unsigned *width_ret, unsigned *height_ret, MipmapPolicy mipmaps)
167 SDL_Surface *surf = IMG_Load(filename);
168 if (surf == nullptr) {
169 fprintf(stderr, "IMG_Load(%s): %s\n", filename, IMG_GetError());
173 // For whatever reason, SDL doesn't support converting to YUV surfaces
174 // nor grayscale, so we'll do it ourselves.
175 SDL_Surface *rgb_surf = SDL_ConvertSurfaceFormat(surf, SDL_PIXELFORMAT_RGBA32, /*flags=*/0);
176 if (rgb_surf == nullptr) {
177 fprintf(stderr, "SDL_ConvertSurfaceFormat(%s): %s\n", filename, SDL_GetError());
181 SDL_FreeSurface(surf);
183 unsigned width = rgb_surf->w, height = rgb_surf->h;
184 const uint8_t *sptr = (uint8_t *)rgb_surf->pixels;
185 unique_ptr<uint8_t[]> pix(new uint8_t[width * height * 4]);
187 // Extract the Y component, and convert to bottom-left origin.
188 for (unsigned y = 0; y < height; ++y) {
189 unsigned y2 = height - 1 - y;
190 memcpy(pix.get() + y * width * 4, sptr + y2 * rgb_surf->pitch, width * 4);
192 SDL_FreeSurface(rgb_surf);
194 int num_levels = (mipmaps == WITH_MIPMAPS) ? find_num_levels(width, height) : 1;
197 glCreateTextures(GL_TEXTURE_2D, 1, &tex);
198 glTextureStorage2D(tex, num_levels, GL_RGBA8, width, height);
199 glTextureSubImage2D(tex, 0, 0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pix.get());
201 if (mipmaps == WITH_MIPMAPS) {
202 glGenerateTextureMipmap(tex);
206 *height_ret = height;
211 GLuint link_program(GLuint vs_obj, GLuint fs_obj)
213 GLuint program = glCreateProgram();
214 glAttachShader(program, vs_obj);
215 glAttachShader(program, fs_obj);
216 glLinkProgram(program);
218 glGetProgramiv(program, GL_LINK_STATUS, &success);
219 if (success == GL_FALSE) {
220 GLchar error_log[1024] = {0};
221 glGetProgramInfoLog(program, 1024, nullptr, error_log);
222 fprintf(stderr, "Error linking program: %s\n", error_log);
228 void bind_sampler(GLuint program, GLint location, GLuint texture_unit, GLuint tex, GLuint sampler)
230 if (location == -1) {
234 glBindTextureUnit(texture_unit, tex);
235 glBindSampler(texture_unit, sampler);
236 glProgramUniform1i(program, location, texture_unit);
239 template<size_t num_elements>
240 void PersistentFBOSet<num_elements>::render_to(const array<GLuint, num_elements> &textures)
242 auto it = fbos.find(textures);
243 if (it != fbos.end()) {
244 glBindFramebuffer(GL_FRAMEBUFFER, it->second);
249 glCreateFramebuffers(1, &fbo);
250 GLenum bufs[num_elements];
251 for (size_t i = 0; i < num_elements; ++i) {
252 glNamedFramebufferTexture(fbo, GL_COLOR_ATTACHMENT0 + i, textures[i], 0);
253 bufs[i] = GL_COLOR_ATTACHMENT0 + i;
255 glNamedFramebufferDrawBuffers(fbo, num_elements, bufs);
257 fbos[textures] = fbo;
258 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
261 template<size_t num_elements>
262 void PersistentFBOSetWithDepth<num_elements>::render_to(GLuint depth_rb, const array<GLuint, num_elements> &textures)
264 auto key = make_pair(depth_rb, textures);
266 auto it = fbos.find(key);
267 if (it != fbos.end()) {
268 glBindFramebuffer(GL_FRAMEBUFFER, it->second);
273 glCreateFramebuffers(1, &fbo);
274 GLenum bufs[num_elements];
275 glNamedFramebufferRenderbuffer(fbo, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depth_rb);
276 for (size_t i = 0; i < num_elements; ++i) {
277 glNamedFramebufferTexture(fbo, GL_COLOR_ATTACHMENT0 + i, textures[i], 0);
278 bufs[i] = GL_COLOR_ATTACHMENT0 + i;
280 glNamedFramebufferDrawBuffers(fbo, num_elements, bufs);
283 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
286 GrayscaleConversion::GrayscaleConversion()
288 gray_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
289 gray_fs_obj = compile_shader(read_file("gray.frag"), GL_FRAGMENT_SHADER);
290 gray_program = link_program(gray_vs_obj, gray_fs_obj);
292 // Set up the VAO containing all the required position/texcoord data.
293 glCreateVertexArrays(1, &gray_vao);
294 glBindVertexArray(gray_vao);
296 GLint position_attrib = glGetAttribLocation(gray_program, "position");
297 glEnableVertexArrayAttrib(gray_vao, position_attrib);
298 glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
300 uniform_tex = glGetUniformLocation(gray_program, "tex");
303 void GrayscaleConversion::exec(GLint tex, GLint gray_tex, int width, int height, int num_layers)
305 glUseProgram(gray_program);
306 bind_sampler(gray_program, uniform_tex, 0, tex, nearest_sampler);
308 glViewport(0, 0, width, height);
309 fbos.render_to(gray_tex);
310 glBindVertexArray(gray_vao);
312 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
317 sobel_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
318 sobel_fs_obj = compile_shader(read_file("sobel.frag"), GL_FRAGMENT_SHADER);
319 sobel_program = link_program(sobel_vs_obj, sobel_fs_obj);
321 uniform_tex = glGetUniformLocation(sobel_program, "tex");
324 void Sobel::exec(GLint tex_view, GLint grad_tex, int level_width, int level_height, int num_layers)
326 glUseProgram(sobel_program);
327 bind_sampler(sobel_program, uniform_tex, 0, tex_view, nearest_sampler);
329 glViewport(0, 0, level_width, level_height);
330 fbos.render_to(grad_tex);
332 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
335 MotionSearch::MotionSearch()
337 motion_vs_obj = compile_shader(read_file("motion_search.vert"), GL_VERTEX_SHADER);
338 motion_fs_obj = compile_shader(read_file("motion_search.frag"), GL_FRAGMENT_SHADER);
339 motion_search_program = link_program(motion_vs_obj, motion_fs_obj);
341 uniform_inv_image_size = glGetUniformLocation(motion_search_program, "inv_image_size");
342 uniform_inv_prev_level_size = glGetUniformLocation(motion_search_program, "inv_prev_level_size");
343 uniform_out_flow_size = glGetUniformLocation(motion_search_program, "out_flow_size");
344 uniform_image_tex = glGetUniformLocation(motion_search_program, "image_tex");
345 uniform_grad_tex = glGetUniformLocation(motion_search_program, "grad_tex");
346 uniform_flow_tex = glGetUniformLocation(motion_search_program, "flow_tex");
349 void MotionSearch::exec(GLuint tex_view, GLuint grad_tex, GLuint flow_tex, GLuint flow_out_tex, int level_width, int level_height, int prev_level_width, int prev_level_height, int width_patches, int height_patches, int num_layers)
351 glUseProgram(motion_search_program);
353 bind_sampler(motion_search_program, uniform_image_tex, 0, tex_view, linear_sampler);
354 bind_sampler(motion_search_program, uniform_grad_tex, 1, grad_tex, nearest_sampler);
355 bind_sampler(motion_search_program, uniform_flow_tex, 2, flow_tex, linear_sampler);
357 glProgramUniform2f(motion_search_program, uniform_inv_image_size, 1.0f / level_width, 1.0f / level_height);
358 glProgramUniform2f(motion_search_program, uniform_inv_prev_level_size, 1.0f / prev_level_width, 1.0f / prev_level_height);
359 glProgramUniform2f(motion_search_program, uniform_out_flow_size, width_patches, height_patches);
361 glViewport(0, 0, width_patches, height_patches);
362 fbos.render_to(flow_out_tex);
363 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
368 densify_vs_obj = compile_shader(read_file("densify.vert"), GL_VERTEX_SHADER);
369 densify_fs_obj = compile_shader(read_file("densify.frag"), GL_FRAGMENT_SHADER);
370 densify_program = link_program(densify_vs_obj, densify_fs_obj);
372 uniform_patch_size = glGetUniformLocation(densify_program, "patch_size");
373 uniform_image_tex = glGetUniformLocation(densify_program, "image_tex");
374 uniform_flow_tex = glGetUniformLocation(densify_program, "flow_tex");
377 void Densify::exec(GLuint tex_view, GLuint flow_tex, GLuint dense_flow_tex, int level_width, int level_height, int width_patches, int height_patches, int num_layers)
379 glUseProgram(densify_program);
381 bind_sampler(densify_program, uniform_image_tex, 0, tex_view, linear_sampler);
382 bind_sampler(densify_program, uniform_flow_tex, 1, flow_tex, nearest_sampler);
384 glProgramUniform2f(densify_program, uniform_patch_size,
385 float(patch_size_pixels) / level_width,
386 float(patch_size_pixels) / level_height);
388 glViewport(0, 0, level_width, level_height);
390 glBlendFunc(GL_ONE, GL_ONE);
391 fbos.render_to(dense_flow_tex);
392 glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
393 glClear(GL_COLOR_BUFFER_BIT);
394 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, width_patches * height_patches * num_layers);
399 prewarp_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
400 prewarp_fs_obj = compile_shader(read_file("prewarp.frag"), GL_FRAGMENT_SHADER);
401 prewarp_program = link_program(prewarp_vs_obj, prewarp_fs_obj);
403 uniform_image_tex = glGetUniformLocation(prewarp_program, "image_tex");
404 uniform_flow_tex = glGetUniformLocation(prewarp_program, "flow_tex");
407 void Prewarp::exec(GLuint tex_view, GLuint flow_tex, GLuint I_tex, GLuint I_t_tex, GLuint normalized_flow_tex, int level_width, int level_height, int num_layers)
409 glUseProgram(prewarp_program);
411 bind_sampler(prewarp_program, uniform_image_tex, 0, tex_view, linear_sampler);
412 bind_sampler(prewarp_program, uniform_flow_tex, 1, flow_tex, nearest_sampler);
414 glViewport(0, 0, level_width, level_height);
416 fbos.render_to(I_tex, I_t_tex, normalized_flow_tex);
417 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
420 Derivatives::Derivatives()
422 derivatives_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
423 derivatives_fs_obj = compile_shader(read_file("derivatives.frag"), GL_FRAGMENT_SHADER);
424 derivatives_program = link_program(derivatives_vs_obj, derivatives_fs_obj);
426 uniform_tex = glGetUniformLocation(derivatives_program, "tex");
429 void Derivatives::exec(GLuint input_tex, GLuint I_x_y_tex, GLuint beta_0_tex, int level_width, int level_height, int num_layers)
431 glUseProgram(derivatives_program);
433 bind_sampler(derivatives_program, uniform_tex, 0, input_tex, nearest_sampler);
435 glViewport(0, 0, level_width, level_height);
437 fbos.render_to(I_x_y_tex, beta_0_tex);
438 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
441 ComputeDiffusivity::ComputeDiffusivity()
443 diffusivity_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
444 diffusivity_fs_obj = compile_shader(read_file("diffusivity.frag"), GL_FRAGMENT_SHADER);
445 diffusivity_program = link_program(diffusivity_vs_obj, diffusivity_fs_obj);
447 uniform_flow_tex = glGetUniformLocation(diffusivity_program, "flow_tex");
448 uniform_diff_flow_tex = glGetUniformLocation(diffusivity_program, "diff_flow_tex");
449 uniform_alpha = glGetUniformLocation(diffusivity_program, "alpha");
450 uniform_zero_diff_flow = glGetUniformLocation(diffusivity_program, "zero_diff_flow");
453 void ComputeDiffusivity::exec(GLuint flow_tex, GLuint diff_flow_tex, GLuint diffusivity_tex, int level_width, int level_height, bool zero_diff_flow, int num_layers)
455 glUseProgram(diffusivity_program);
457 bind_sampler(diffusivity_program, uniform_flow_tex, 0, flow_tex, nearest_sampler);
458 bind_sampler(diffusivity_program, uniform_diff_flow_tex, 1, diff_flow_tex, nearest_sampler);
459 glProgramUniform1f(diffusivity_program, uniform_alpha, vr_alpha);
460 glProgramUniform1i(diffusivity_program, uniform_zero_diff_flow, zero_diff_flow);
462 glViewport(0, 0, level_width, level_height);
465 fbos.render_to(diffusivity_tex);
466 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
469 SetupEquations::SetupEquations()
471 equations_vs_obj = compile_shader(read_file("equations.vert"), GL_VERTEX_SHADER);
472 equations_fs_obj = compile_shader(read_file("equations.frag"), GL_FRAGMENT_SHADER);
473 equations_program = link_program(equations_vs_obj, equations_fs_obj);
475 uniform_I_x_y_tex = glGetUniformLocation(equations_program, "I_x_y_tex");
476 uniform_I_t_tex = glGetUniformLocation(equations_program, "I_t_tex");
477 uniform_diff_flow_tex = glGetUniformLocation(equations_program, "diff_flow_tex");
478 uniform_base_flow_tex = glGetUniformLocation(equations_program, "base_flow_tex");
479 uniform_beta_0_tex = glGetUniformLocation(equations_program, "beta_0_tex");
480 uniform_diffusivity_tex = glGetUniformLocation(equations_program, "diffusivity_tex");
481 uniform_gamma = glGetUniformLocation(equations_program, "gamma");
482 uniform_delta = glGetUniformLocation(equations_program, "delta");
483 uniform_zero_diff_flow = glGetUniformLocation(equations_program, "zero_diff_flow");
486 void SetupEquations::exec(GLuint I_x_y_tex, GLuint I_t_tex, GLuint diff_flow_tex, GLuint base_flow_tex, GLuint beta_0_tex, GLuint diffusivity_tex, GLuint equation_red_tex, GLuint equation_black_tex, int level_width, int level_height, bool zero_diff_flow, int num_layers)
488 glUseProgram(equations_program);
490 bind_sampler(equations_program, uniform_I_x_y_tex, 0, I_x_y_tex, nearest_sampler);
491 bind_sampler(equations_program, uniform_I_t_tex, 1, I_t_tex, nearest_sampler);
492 bind_sampler(equations_program, uniform_diff_flow_tex, 2, diff_flow_tex, nearest_sampler);
493 bind_sampler(equations_program, uniform_base_flow_tex, 3, base_flow_tex, nearest_sampler);
494 bind_sampler(equations_program, uniform_beta_0_tex, 4, beta_0_tex, nearest_sampler);
495 bind_sampler(equations_program, uniform_diffusivity_tex, 5, diffusivity_tex, zero_border_sampler);
496 glProgramUniform1f(equations_program, uniform_delta, vr_delta);
497 glProgramUniform1f(equations_program, uniform_gamma, vr_gamma);
498 glProgramUniform1i(equations_program, uniform_zero_diff_flow, zero_diff_flow);
500 glViewport(0, 0, (level_width + 1) / 2, level_height);
502 fbos.render_to(equation_red_tex, equation_black_tex);
503 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
508 sor_vs_obj = compile_shader(read_file("sor.vert"), GL_VERTEX_SHADER);
509 sor_fs_obj = compile_shader(read_file("sor.frag"), GL_FRAGMENT_SHADER);
510 sor_program = link_program(sor_vs_obj, sor_fs_obj);
512 uniform_diff_flow_tex = glGetUniformLocation(sor_program, "diff_flow_tex");
513 uniform_equation_red_tex = glGetUniformLocation(sor_program, "equation_red_tex");
514 uniform_equation_black_tex = glGetUniformLocation(sor_program, "equation_black_tex");
515 uniform_diffusivity_tex = glGetUniformLocation(sor_program, "diffusivity_tex");
516 uniform_phase = glGetUniformLocation(sor_program, "phase");
517 uniform_num_nonzero_phases = glGetUniformLocation(sor_program, "num_nonzero_phases");
520 void SOR::exec(GLuint diff_flow_tex, GLuint equation_red_tex, GLuint equation_black_tex, GLuint diffusivity_tex, int level_width, int level_height, int num_iterations, bool zero_diff_flow, int num_layers, ScopedTimer *sor_timer)
522 glUseProgram(sor_program);
524 bind_sampler(sor_program, uniform_diff_flow_tex, 0, diff_flow_tex, nearest_sampler);
525 bind_sampler(sor_program, uniform_diffusivity_tex, 1, diffusivity_tex, zero_border_sampler);
526 bind_sampler(sor_program, uniform_equation_red_tex, 2, equation_red_tex, nearest_sampler);
527 bind_sampler(sor_program, uniform_equation_black_tex, 3, equation_black_tex, nearest_sampler);
529 if (!zero_diff_flow) {
530 glProgramUniform1i(sor_program, uniform_num_nonzero_phases, 2);
533 // NOTE: We bind to the texture we are rendering from, but we never write any value
534 // that we read in the same shader pass (we call discard for red values when we compute
535 // black, and vice versa), and we have barriers between the passes, so we're fine
537 glViewport(0, 0, level_width, level_height);
539 fbos.render_to(diff_flow_tex);
541 for (int i = 0; i < num_iterations; ++i) {
543 ScopedTimer timer("Red pass", sor_timer);
544 if (zero_diff_flow && i == 0) {
545 glProgramUniform1i(sor_program, uniform_num_nonzero_phases, 0);
547 glProgramUniform1i(sor_program, uniform_phase, 0);
548 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
552 ScopedTimer timer("Black pass", sor_timer);
553 if (zero_diff_flow && i == 0) {
554 glProgramUniform1i(sor_program, uniform_num_nonzero_phases, 1);
556 glProgramUniform1i(sor_program, uniform_phase, 1);
557 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
558 if (zero_diff_flow && i == 0) {
559 glProgramUniform1i(sor_program, uniform_num_nonzero_phases, 2);
561 if (i != num_iterations - 1) {
568 AddBaseFlow::AddBaseFlow()
570 add_flow_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
571 add_flow_fs_obj = compile_shader(read_file("add_base_flow.frag"), GL_FRAGMENT_SHADER);
572 add_flow_program = link_program(add_flow_vs_obj, add_flow_fs_obj);
574 uniform_diff_flow_tex = glGetUniformLocation(add_flow_program, "diff_flow_tex");
577 void AddBaseFlow::exec(GLuint base_flow_tex, GLuint diff_flow_tex, int level_width, int level_height, int num_layers)
579 glUseProgram(add_flow_program);
581 bind_sampler(add_flow_program, uniform_diff_flow_tex, 0, diff_flow_tex, nearest_sampler);
583 glViewport(0, 0, level_width, level_height);
585 glBlendFunc(GL_ONE, GL_ONE);
586 fbos.render_to(base_flow_tex);
588 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
591 ResizeFlow::ResizeFlow()
593 resize_flow_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
594 resize_flow_fs_obj = compile_shader(read_file("resize_flow.frag"), GL_FRAGMENT_SHADER);
595 resize_flow_program = link_program(resize_flow_vs_obj, resize_flow_fs_obj);
597 uniform_flow_tex = glGetUniformLocation(resize_flow_program, "flow_tex");
598 uniform_scale_factor = glGetUniformLocation(resize_flow_program, "scale_factor");
601 void ResizeFlow::exec(GLuint flow_tex, GLuint out_tex, int input_width, int input_height, int output_width, int output_height, int num_layers)
603 glUseProgram(resize_flow_program);
605 bind_sampler(resize_flow_program, uniform_flow_tex, 0, flow_tex, nearest_sampler);
607 glProgramUniform2f(resize_flow_program, uniform_scale_factor, float(output_width) / input_width, float(output_height) / input_height);
609 glViewport(0, 0, output_width, output_height);
611 fbos.render_to(out_tex);
613 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
616 DISComputeFlow::DISComputeFlow(int width, int height)
617 : width(width), height(height)
619 // Make some samplers.
620 glCreateSamplers(1, &nearest_sampler);
621 glSamplerParameteri(nearest_sampler, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
622 glSamplerParameteri(nearest_sampler, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
623 glSamplerParameteri(nearest_sampler, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
624 glSamplerParameteri(nearest_sampler, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
626 glCreateSamplers(1, &linear_sampler);
627 glSamplerParameteri(linear_sampler, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
628 glSamplerParameteri(linear_sampler, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
629 glSamplerParameteri(linear_sampler, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
630 glSamplerParameteri(linear_sampler, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
632 // The smoothness is sampled so that once we get to a smoothness involving
633 // a value outside the border, the diffusivity between the two becomes zero.
634 // Similarly, gradients are zero outside the border, since the edge is taken
636 glCreateSamplers(1, &zero_border_sampler);
637 glSamplerParameteri(zero_border_sampler, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
638 glSamplerParameteri(zero_border_sampler, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
639 glSamplerParameteri(zero_border_sampler, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
640 glSamplerParameteri(zero_border_sampler, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
641 float zero[] = { 0.0f, 0.0f, 0.0f, 0.0f }; // Note that zero alpha means we can also see whether we sampled outside the border or not.
642 glSamplerParameterfv(zero_border_sampler, GL_TEXTURE_BORDER_COLOR, zero);
644 // Initial flow is zero, 1x1.
645 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &initial_flow_tex);
646 glTextureStorage3D(initial_flow_tex, 1, GL_RG16F, 1, 1, 1);
647 glClearTexImage(initial_flow_tex, 0, GL_RG, GL_FLOAT, nullptr);
649 // Set up the vertex data that will be shared between all passes.
656 glCreateBuffers(1, &vertex_vbo);
657 glNamedBufferData(vertex_vbo, sizeof(vertices), vertices, GL_STATIC_DRAW);
659 glCreateVertexArrays(1, &vao);
660 glBindVertexArray(vao);
661 glBindBuffer(GL_ARRAY_BUFFER, vertex_vbo);
663 GLint position_attrib = 0; // Hard-coded in every vertex shader.
664 glEnableVertexArrayAttrib(vao, position_attrib);
665 glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
668 GLuint DISComputeFlow::exec(GLuint tex, FlowDirection flow_direction, ResizeStrategy resize_strategy)
670 int num_layers = (flow_direction == FORWARD_AND_BACKWARD) ? 2 : 1;
671 int prev_level_width = 1, prev_level_height = 1;
672 GLuint prev_level_flow_tex = initial_flow_tex;
676 glBindVertexArray(vao);
678 ScopedTimer total_timer("Compute flow", &timers);
679 for (int level = coarsest_level; level >= int(finest_level); --level) {
680 char timer_name[256];
681 snprintf(timer_name, sizeof(timer_name), "Level %d (%d x %d)", level, width >> level, height >> level);
682 ScopedTimer level_timer(timer_name, &total_timer);
684 int level_width = width >> level;
685 int level_height = height >> level;
686 float patch_spacing_pixels = patch_size_pixels * (1.0f - patch_overlap_ratio);
688 // Make sure we have patches at least every Nth pixel, e.g. for width=9
689 // and patch_spacing=3 (the default), we put out patch centers in
690 // x=0, x=3, x=6, x=9, which is four patches. The fragment shader will
691 // lock all the centers to integer coordinates if needed.
692 int width_patches = 1 + ceil(level_width / patch_spacing_pixels);
693 int height_patches = 1 + ceil(level_height / patch_spacing_pixels);
695 // Make sure we always read from the correct level; the chosen
696 // mipmapping could otherwise be rather unpredictable, especially
697 // during motion search.
699 glGenTextures(1, &tex_view);
700 glTextureView(tex_view, GL_TEXTURE_2D_ARRAY, tex, GL_R8, level, 1, 0, 2);
702 // Create a new texture to hold the gradients.
703 GLuint grad_tex = pool.get_texture(GL_R32UI, level_width, level_height, num_layers);
705 // Find the derivative.
707 ScopedTimer timer("Sobel", &level_timer);
708 sobel.exec(tex_view, grad_tex, level_width, level_height, num_layers);
711 // Motion search to find the initial flow. We use the flow from the previous
712 // level (sampled bilinearly; no fancy tricks) as a guide, then search from there.
714 // Create an output flow texture.
715 GLuint flow_out_tex = pool.get_texture(GL_RGB16F, width_patches, height_patches, num_layers);
719 ScopedTimer timer("Motion search", &level_timer);
720 motion_search.exec(tex_view, grad_tex, prev_level_flow_tex, flow_out_tex, level_width, level_height, prev_level_width, prev_level_height, width_patches, height_patches, num_layers);
722 pool.release_texture(grad_tex);
726 // Set up an output texture (cleared in Densify).
727 GLuint dense_flow_tex = pool.get_texture(GL_RGB16F, level_width, level_height, num_layers);
731 ScopedTimer timer("Densification", &level_timer);
732 densify.exec(tex_view, flow_out_tex, dense_flow_tex, level_width, level_height, width_patches, height_patches, num_layers);
734 pool.release_texture(flow_out_tex);
736 // Everything below here in the loop belongs to variational refinement.
737 ScopedTimer varref_timer("Variational refinement", &level_timer);
739 // Prewarping; create I and I_t, and a normalized base flow (so we don't
740 // have to normalize it over and over again, and also save some bandwidth).
742 // During the entire rest of the variational refinement, flow will be measured
743 // in pixels, not 0..1 normalized OpenGL texture coordinates.
744 // This is because variational refinement depends so heavily on derivatives,
745 // which are measured in intensity levels per pixel.
746 GLuint I_tex = pool.get_texture(GL_R16F, level_width, level_height, num_layers);
747 GLuint I_t_tex = pool.get_texture(GL_R16F, level_width, level_height, num_layers);
748 GLuint base_flow_tex = pool.get_texture(GL_RG16F, level_width, level_height, num_layers);
750 ScopedTimer timer("Prewarping", &varref_timer);
751 prewarp.exec(tex_view, dense_flow_tex, I_tex, I_t_tex, base_flow_tex, level_width, level_height, num_layers);
753 pool.release_texture(dense_flow_tex);
754 glDeleteTextures(1, &tex_view);
756 // Calculate I_x and I_y. We're only calculating first derivatives;
757 // the others will be taken on-the-fly in order to sample from fewer
758 // textures overall, since sampling from the L1 cache is cheap.
759 // (TODO: Verify that this is indeed faster than making separate
760 // double-derivative textures.)
761 GLuint I_x_y_tex = pool.get_texture(GL_RG16F, level_width, level_height, num_layers);
762 GLuint beta_0_tex = pool.get_texture(GL_R16F, level_width, level_height, num_layers);
764 ScopedTimer timer("First derivatives", &varref_timer);
765 derivatives.exec(I_tex, I_x_y_tex, beta_0_tex, level_width, level_height, num_layers);
767 pool.release_texture(I_tex);
769 // We need somewhere to store du and dv (the flow increment, relative
770 // to the non-refined base flow u0 and v0). It's initially garbage,
771 // but not read until we've written something sane to it.
772 GLuint diff_flow_tex = pool.get_texture(GL_RG16F, level_width, level_height, num_layers);
774 // And for diffusivity.
775 GLuint diffusivity_tex = pool.get_texture(GL_R16F, level_width, level_height, num_layers);
777 // And finally for the equation set. See SetupEquations for
778 // the storage format.
779 GLuint equation_red_tex = pool.get_texture(GL_RGBA32UI, (level_width + 1) / 2, level_height, num_layers);
780 GLuint equation_black_tex = pool.get_texture(GL_RGBA32UI, (level_width + 1) / 2, level_height, num_layers);
782 for (int outer_idx = 0; outer_idx < level + 1; ++outer_idx) {
783 // Calculate the diffusivity term for each pixel.
785 ScopedTimer timer("Compute diffusivity", &varref_timer);
786 compute_diffusivity.exec(base_flow_tex, diff_flow_tex, diffusivity_tex, level_width, level_height, outer_idx == 0, num_layers);
789 // Set up the 2x2 equation system for each pixel.
791 ScopedTimer timer("Set up equations", &varref_timer);
792 setup_equations.exec(I_x_y_tex, I_t_tex, diff_flow_tex, base_flow_tex, beta_0_tex, diffusivity_tex, equation_red_tex, equation_black_tex, level_width, level_height, outer_idx == 0, num_layers);
795 // Run a few SOR iterations. Note that these are to/from the same texture.
797 ScopedTimer timer("SOR", &varref_timer);
798 sor.exec(diff_flow_tex, equation_red_tex, equation_black_tex, diffusivity_tex, level_width, level_height, 5, outer_idx == 0, num_layers, &timer);
802 pool.release_texture(I_t_tex);
803 pool.release_texture(I_x_y_tex);
804 pool.release_texture(beta_0_tex);
805 pool.release_texture(diffusivity_tex);
806 pool.release_texture(equation_red_tex);
807 pool.release_texture(equation_black_tex);
809 // Add the differential flow found by the variational refinement to the base flow,
810 // giving the final flow estimate for this level.
811 // The output is in diff_flow_tex; we don't need to make a new texture.
813 // Disabling this doesn't save any time (although we could easily make it so that
814 // it is more efficient), but it helps debug the motion search.
815 if (enable_variational_refinement) {
816 ScopedTimer timer("Add differential flow", &varref_timer);
817 add_base_flow.exec(base_flow_tex, diff_flow_tex, level_width, level_height, num_layers);
819 pool.release_texture(diff_flow_tex);
821 if (prev_level_flow_tex != initial_flow_tex) {
822 pool.release_texture(prev_level_flow_tex);
824 prev_level_flow_tex = base_flow_tex;
825 prev_level_width = level_width;
826 prev_level_height = level_height;
834 // Scale up the flow to the final size (if needed).
835 if (finest_level == 0 || resize_strategy == DO_NOT_RESIZE_FLOW) {
836 return prev_level_flow_tex;
838 GLuint final_tex = pool.get_texture(GL_RG16F, width, height, num_layers);
839 resize_flow.exec(prev_level_flow_tex, final_tex, prev_level_width, prev_level_height, width, height, num_layers);
840 pool.release_texture(prev_level_flow_tex);
847 splat_vs_obj = compile_shader(read_file("splat.vert"), GL_VERTEX_SHADER);
848 splat_fs_obj = compile_shader(read_file("splat.frag"), GL_FRAGMENT_SHADER);
849 splat_program = link_program(splat_vs_obj, splat_fs_obj);
851 uniform_splat_size = glGetUniformLocation(splat_program, "splat_size");
852 uniform_alpha = glGetUniformLocation(splat_program, "alpha");
853 uniform_image_tex = glGetUniformLocation(splat_program, "image_tex");
854 uniform_flow_tex = glGetUniformLocation(splat_program, "flow_tex");
855 uniform_inv_flow_size = glGetUniformLocation(splat_program, "inv_flow_size");
858 void Splat::exec(GLuint image_tex, GLuint bidirectional_flow_tex, GLuint flow_tex, GLuint depth_rb, int width, int height, float alpha)
860 glUseProgram(splat_program);
862 bind_sampler(splat_program, uniform_image_tex, 0, image_tex, linear_sampler);
863 bind_sampler(splat_program, uniform_flow_tex, 1, bidirectional_flow_tex, nearest_sampler);
865 // FIXME: This is set to 1.0 right now so not to trigger Haswell's “PMA stall”.
866 // Move to 2.0 later, or even 4.0.
867 // (Since we have hole filling, it's not critical, but larger values seem to do
868 // better than hole filling for large motion, blurs etc.)
869 float splat_size = 1.0f; // 4x4 splat means 16x overdraw, 2x2 splat means 4x overdraw.
870 glProgramUniform2f(splat_program, uniform_splat_size, splat_size / width, splat_size / height);
871 glProgramUniform1f(splat_program, uniform_alpha, alpha);
872 glProgramUniform2f(splat_program, uniform_inv_flow_size, 1.0f / width, 1.0f / height);
874 glViewport(0, 0, width, height);
876 glEnable(GL_DEPTH_TEST);
877 glDepthFunc(GL_LESS); // We store the difference between I_0 and I_1, where less difference is good. (Default 1.0 is effectively +inf, which always loses.)
879 fbos.render_to(depth_rb, flow_tex);
881 // Evidently NVIDIA doesn't use fast clears for glClearTexImage, so clear now that
882 // we've got it bound.
883 glClearColor(1000.0f, 1000.0f, 0.0f, 1.0f); // Invalid flow.
884 glClearDepth(1.0f); // Effectively infinity.
885 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
887 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, width * height * 2);
889 glDisable(GL_DEPTH_TEST);
894 fill_vs_obj = compile_shader(read_file("hole_fill.vert"), GL_VERTEX_SHADER);
895 fill_fs_obj = compile_shader(read_file("hole_fill.frag"), GL_FRAGMENT_SHADER);
896 fill_program = link_program(fill_vs_obj, fill_fs_obj);
898 uniform_tex = glGetUniformLocation(fill_program, "tex");
899 uniform_z = glGetUniformLocation(fill_program, "z");
900 uniform_sample_offset = glGetUniformLocation(fill_program, "sample_offset");
903 void HoleFill::exec(GLuint flow_tex, GLuint depth_rb, GLuint temp_tex[3], int width, int height)
905 glUseProgram(fill_program);
907 bind_sampler(fill_program, uniform_tex, 0, flow_tex, nearest_sampler);
909 glProgramUniform1f(fill_program, uniform_z, 1.0f - 1.0f / 1024.0f);
911 glViewport(0, 0, width, height);
913 glEnable(GL_DEPTH_TEST);
914 glDepthFunc(GL_LESS); // Only update the values > 0.999f (ie., only invalid pixels).
916 fbos.render_to(depth_rb, flow_tex); // NOTE: Reading and writing to the same texture.
918 // Fill holes from the left, by shifting 1, 2, 4, 8, etc. pixels to the right.
919 for (int offs = 1; offs < width; offs *= 2) {
920 glProgramUniform2f(fill_program, uniform_sample_offset, -offs / float(width), 0.0f);
921 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
924 glCopyImageSubData(flow_tex, GL_TEXTURE_2D, 0, 0, 0, 0, temp_tex[0], GL_TEXTURE_2D, 0, 0, 0, 0, width, height, 1);
926 // Similar to the right; adjust Z a bit down, so that we re-fill the pixels that
927 // were overwritten in the last algorithm.
928 glProgramUniform1f(fill_program, uniform_z, 1.0f - 2.0f / 1024.0f);
929 for (int offs = 1; offs < width; offs *= 2) {
930 glProgramUniform2f(fill_program, uniform_sample_offset, offs / float(width), 0.0f);
931 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
934 glCopyImageSubData(flow_tex, GL_TEXTURE_2D, 0, 0, 0, 0, temp_tex[1], GL_TEXTURE_2D, 0, 0, 0, 0, width, height, 1);
937 glProgramUniform1f(fill_program, uniform_z, 1.0f - 3.0f / 1024.0f);
938 for (int offs = 1; offs < height; offs *= 2) {
939 glProgramUniform2f(fill_program, uniform_sample_offset, 0.0f, -offs / float(height));
940 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
943 glCopyImageSubData(flow_tex, GL_TEXTURE_2D, 0, 0, 0, 0, temp_tex[2], GL_TEXTURE_2D, 0, 0, 0, 0, width, height, 1);
946 glProgramUniform1f(fill_program, uniform_z, 1.0f - 4.0f / 1024.0f);
947 for (int offs = 1; offs < height; offs *= 2) {
948 glProgramUniform2f(fill_program, uniform_sample_offset, 0.0f, offs / float(height));
949 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
953 glDisable(GL_DEPTH_TEST);
956 HoleBlend::HoleBlend()
958 blend_vs_obj = compile_shader(read_file("hole_fill.vert"), GL_VERTEX_SHADER); // Reuse the vertex shader from the fill.
959 blend_fs_obj = compile_shader(read_file("hole_blend.frag"), GL_FRAGMENT_SHADER);
960 blend_program = link_program(blend_vs_obj, blend_fs_obj);
962 uniform_left_tex = glGetUniformLocation(blend_program, "left_tex");
963 uniform_right_tex = glGetUniformLocation(blend_program, "right_tex");
964 uniform_up_tex = glGetUniformLocation(blend_program, "up_tex");
965 uniform_down_tex = glGetUniformLocation(blend_program, "down_tex");
966 uniform_z = glGetUniformLocation(blend_program, "z");
967 uniform_sample_offset = glGetUniformLocation(blend_program, "sample_offset");
970 void HoleBlend::exec(GLuint flow_tex, GLuint depth_rb, GLuint temp_tex[3], int width, int height)
972 glUseProgram(blend_program);
974 bind_sampler(blend_program, uniform_left_tex, 0, temp_tex[0], nearest_sampler);
975 bind_sampler(blend_program, uniform_right_tex, 1, temp_tex[1], nearest_sampler);
976 bind_sampler(blend_program, uniform_up_tex, 2, temp_tex[2], nearest_sampler);
977 bind_sampler(blend_program, uniform_down_tex, 3, flow_tex, nearest_sampler);
979 glProgramUniform1f(blend_program, uniform_z, 1.0f - 4.0f / 1024.0f);
980 glProgramUniform2f(blend_program, uniform_sample_offset, 0.0f, 0.0f);
982 glViewport(0, 0, width, height);
984 glEnable(GL_DEPTH_TEST);
985 glDepthFunc(GL_LEQUAL); // Skip over all of the pixels that were never holes to begin with.
987 fbos.render_to(depth_rb, flow_tex); // NOTE: Reading and writing to the same texture.
989 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
991 glDisable(GL_DEPTH_TEST);
996 blend_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
997 blend_fs_obj = compile_shader(read_file("blend.frag"), GL_FRAGMENT_SHADER);
998 blend_program = link_program(blend_vs_obj, blend_fs_obj);
1000 uniform_image_tex = glGetUniformLocation(blend_program, "image_tex");
1001 uniform_flow_tex = glGetUniformLocation(blend_program, "flow_tex");
1002 uniform_alpha = glGetUniformLocation(blend_program, "alpha");
1003 uniform_flow_consistency_tolerance = glGetUniformLocation(blend_program, "flow_consistency_tolerance");
1006 void Blend::exec(GLuint image_tex, GLuint flow_tex, GLuint output_tex, int level_width, int level_height, float alpha)
1008 glUseProgram(blend_program);
1009 bind_sampler(blend_program, uniform_image_tex, 0, image_tex, linear_sampler);
1010 bind_sampler(blend_program, uniform_flow_tex, 1, flow_tex, linear_sampler); // May be upsampled.
1011 glProgramUniform1f(blend_program, uniform_alpha, alpha);
1013 glViewport(0, 0, level_width, level_height);
1014 fbos.render_to(output_tex);
1015 glDisable(GL_BLEND); // A bit ironic, perhaps.
1016 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
1019 Interpolate::Interpolate(int width, int height, int flow_level)
1020 : width(width), height(height), flow_level(flow_level) {
1021 // Set up the vertex data that will be shared between all passes.
1022 float vertices[] = {
1028 glCreateBuffers(1, &vertex_vbo);
1029 glNamedBufferData(vertex_vbo, sizeof(vertices), vertices, GL_STATIC_DRAW);
1031 glCreateVertexArrays(1, &vao);
1032 glBindVertexArray(vao);
1033 glBindBuffer(GL_ARRAY_BUFFER, vertex_vbo);
1035 GLint position_attrib = 0; // Hard-coded in every vertex shader.
1036 glEnableVertexArrayAttrib(vao, position_attrib);
1037 glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
1040 GLuint Interpolate::exec(GLuint image_tex, GLuint bidirectional_flow_tex, GLuint width, GLuint height, float alpha)
1044 ScopedTimer total_timer("Interpolate", &timers);
1046 glBindVertexArray(vao);
1048 // Pick out the right level to test splatting results on.
1050 glGenTextures(1, &tex_view);
1051 glTextureView(tex_view, GL_TEXTURE_2D_ARRAY, image_tex, GL_RGBA8, flow_level, 1, 0, 2);
1053 int flow_width = width >> flow_level;
1054 int flow_height = height >> flow_level;
1056 GLuint flow_tex = pool.get_texture(GL_RG16F, flow_width, flow_height);
1057 GLuint depth_rb = pool.get_renderbuffer(GL_DEPTH_COMPONENT16, flow_width, flow_height); // Used for ranking flows.
1060 ScopedTimer timer("Splat", &total_timer);
1061 splat.exec(tex_view, bidirectional_flow_tex, flow_tex, depth_rb, flow_width, flow_height, alpha);
1063 glDeleteTextures(1, &tex_view);
1066 temp_tex[0] = pool.get_texture(GL_RG16F, flow_width, flow_height);
1067 temp_tex[1] = pool.get_texture(GL_RG16F, flow_width, flow_height);
1068 temp_tex[2] = pool.get_texture(GL_RG16F, flow_width, flow_height);
1071 ScopedTimer timer("Fill holes", &total_timer);
1072 hole_fill.exec(flow_tex, depth_rb, temp_tex, flow_width, flow_height);
1073 hole_blend.exec(flow_tex, depth_rb, temp_tex, flow_width, flow_height);
1076 pool.release_texture(temp_tex[0]);
1077 pool.release_texture(temp_tex[1]);
1078 pool.release_texture(temp_tex[2]);
1079 pool.release_renderbuffer(depth_rb);
1081 GLuint output_tex = pool.get_texture(GL_RGBA8, width, height);
1083 ScopedTimer timer("Blend", &total_timer);
1084 blend.exec(image_tex, flow_tex, output_tex, width, height, alpha);
1086 pool.release_texture(flow_tex);
1095 GLuint TexturePool::get_texture(GLenum format, GLuint width, GLuint height, GLuint num_layers)
1097 for (Texture &tex : textures) {
1098 if (!tex.in_use && !tex.is_renderbuffer && tex.format == format &&
1099 tex.width == width && tex.height == height && tex.num_layers == num_layers) {
1106 if (num_layers == 0) {
1107 glCreateTextures(GL_TEXTURE_2D, 1, &tex.tex_num);
1108 glTextureStorage2D(tex.tex_num, 1, format, width, height);
1110 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &tex.tex_num);
1111 glTextureStorage3D(tex.tex_num, 1, format, width, height, num_layers);
1113 tex.format = format;
1115 tex.height = height;
1116 tex.num_layers = num_layers;
1118 tex.is_renderbuffer = false;
1119 textures.push_back(tex);
1123 GLuint TexturePool::get_renderbuffer(GLenum format, GLuint width, GLuint height)
1125 for (Texture &tex : textures) {
1126 if (!tex.in_use && tex.is_renderbuffer && tex.format == format &&
1127 tex.width == width && tex.height == height) {
1134 glCreateRenderbuffers(1, &tex.tex_num);
1135 glNamedRenderbufferStorage(tex.tex_num, format, width, height);
1137 tex.format = format;
1139 tex.height = height;
1141 tex.is_renderbuffer = true;
1142 textures.push_back(tex);
1146 void TexturePool::release_texture(GLuint tex_num)
1148 for (Texture &tex : textures) {
1149 if (!tex.is_renderbuffer && tex.tex_num == tex_num) {
1158 void TexturePool::release_renderbuffer(GLuint tex_num)
1160 for (Texture &tex : textures) {
1161 if (tex.is_renderbuffer && tex.tex_num == tex_num) {
1170 // OpenGL uses a bottom-left coordinate system, .flo files use a top-left coordinate system.
1171 void flip_coordinate_system(float *dense_flow, unsigned width, unsigned height)
1173 for (unsigned i = 0; i < width * height; ++i) {
1174 dense_flow[i * 2 + 1] = -dense_flow[i * 2 + 1];
1178 // Not relevant for RGB.
1179 void flip_coordinate_system(uint8_t *dense_flow, unsigned width, unsigned height)
1183 void write_flow(const char *filename, const float *dense_flow, unsigned width, unsigned height)
1185 FILE *flowfp = fopen(filename, "wb");
1186 fprintf(flowfp, "FEIH");
1187 fwrite(&width, 4, 1, flowfp);
1188 fwrite(&height, 4, 1, flowfp);
1189 for (unsigned y = 0; y < height; ++y) {
1190 int yy = height - y - 1;
1191 fwrite(&dense_flow[yy * width * 2], width * 2 * sizeof(float), 1, flowfp);
1196 // Not relevant for RGB.
1197 void write_flow(const char *filename, const uint8_t *dense_flow, unsigned width, unsigned height)
1202 void write_ppm(const char *filename, const float *dense_flow, unsigned width, unsigned height)
1204 FILE *fp = fopen(filename, "wb");
1205 fprintf(fp, "P6\n%d %d\n255\n", width, height);
1206 for (unsigned y = 0; y < unsigned(height); ++y) {
1207 int yy = height - y - 1;
1208 for (unsigned x = 0; x < unsigned(width); ++x) {
1209 float du = dense_flow[(yy * width + x) * 2 + 0];
1210 float dv = dense_flow[(yy * width + x) * 2 + 1];
1213 flow2rgb(du, dv, &r, &g, &b);
1222 void write_ppm(const char *filename, const uint8_t *rgba, unsigned width, unsigned height)
1224 unique_ptr<uint8_t[]> rgb_line(new uint8_t[width * 3 + 1]);
1226 FILE *fp = fopen(filename, "wb");
1227 fprintf(fp, "P6\n%d %d\n255\n", width, height);
1228 for (unsigned y = 0; y < height; ++y) {
1229 unsigned y2 = height - 1 - y;
1230 for (size_t x = 0; x < width; ++x) {
1231 memcpy(&rgb_line[x * 3], &rgba[(y2 * width + x) * 4], 4);
1233 fwrite(rgb_line.get(), width * 3, 1, fp);
1240 static constexpr GLenum gl_format = GL_RG;
1241 static constexpr GLenum gl_type = GL_FLOAT;
1242 static constexpr int num_channels = 2;
1246 using type = uint8_t;
1247 static constexpr GLenum gl_format = GL_RGBA;
1248 static constexpr GLenum gl_type = GL_UNSIGNED_BYTE;
1249 static constexpr int num_channels = 4;
1252 template <class Type>
1253 void finish_one_read(GLuint width, GLuint height)
1255 using T = typename Type::type;
1256 constexpr int bytes_per_pixel = Type::num_channels * sizeof(T);
1258 assert(!reads_in_progress.empty());
1259 ReadInProgress read = reads_in_progress.front();
1260 reads_in_progress.pop_front();
1262 unique_ptr<T[]> flow(new typename Type::type[width * height * Type::num_channels]);
1263 void *buf = glMapNamedBufferRange(read.pbo, 0, width * height * bytes_per_pixel, GL_MAP_READ_BIT); // Blocks if the read isn't done yet.
1264 memcpy(flow.get(), buf, width * height * bytes_per_pixel); // TODO: Unneeded for RGBType, since flip_coordinate_system() does nothing.:
1265 glUnmapNamedBuffer(read.pbo);
1266 spare_pbos.push(read.pbo);
1268 flip_coordinate_system(flow.get(), width, height);
1269 if (!read.flow_filename.empty()) {
1270 write_flow(read.flow_filename.c_str(), flow.get(), width, height);
1271 fprintf(stderr, "%s %s -> %s\n", read.filename0.c_str(), read.filename1.c_str(), read.flow_filename.c_str());
1273 if (!read.ppm_filename.empty()) {
1274 write_ppm(read.ppm_filename.c_str(), flow.get(), width, height);
1278 template <class Type>
1279 void schedule_read(GLuint tex, GLuint width, GLuint height, const char *filename0, const char *filename1, const char *flow_filename, const char *ppm_filename)
1281 using T = typename Type::type;
1282 constexpr int bytes_per_pixel = Type::num_channels * sizeof(T);
1284 if (spare_pbos.empty()) {
1285 finish_one_read<Type>(width, height);
1287 assert(!spare_pbos.empty());
1288 reads_in_progress.emplace_back(ReadInProgress{ spare_pbos.top(), filename0, filename1, flow_filename, ppm_filename });
1289 glBindBuffer(GL_PIXEL_PACK_BUFFER, spare_pbos.top());
1291 glGetTextureImage(tex, 0, Type::gl_format, Type::gl_type, width * height * bytes_per_pixel, nullptr);
1292 glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
1295 void compute_flow_only(int argc, char **argv, int optind)
1297 const char *filename0 = argc >= (optind + 1) ? argv[optind] : "test1499.png";
1298 const char *filename1 = argc >= (optind + 2) ? argv[optind + 1] : "test1500.png";
1299 const char *flow_filename = argc >= (optind + 3) ? argv[optind + 2] : "flow.flo";
1302 unsigned width1, height1, width2, height2;
1303 GLuint tex0 = load_texture(filename0, &width1, &height1, WITHOUT_MIPMAPS);
1304 GLuint tex1 = load_texture(filename1, &width2, &height2, WITHOUT_MIPMAPS);
1306 if (width1 != width2 || height1 != height2) {
1307 fprintf(stderr, "Image dimensions don't match (%dx%d versus %dx%d)\n",
1308 width1, height1, width2, height2);
1312 // Move them into an array texture, since that's how the rest of the code
1315 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &image_tex);
1316 glTextureStorage3D(image_tex, 1, GL_RGBA8, width1, height1, 2);
1317 glCopyImageSubData(tex0, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 0, width1, height1, 1);
1318 glCopyImageSubData(tex1, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 1, width1, height1, 1);
1319 glDeleteTextures(1, &tex0);
1320 glDeleteTextures(1, &tex1);
1322 // Set up some PBOs to do asynchronous readback.
1324 glCreateBuffers(5, pbos);
1325 for (int i = 0; i < 5; ++i) {
1326 glNamedBufferData(pbos[i], width1 * height1 * 2 * 2 * sizeof(float), nullptr, GL_STREAM_READ);
1327 spare_pbos.push(pbos[i]);
1330 int levels = find_num_levels(width1, height1);
1333 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &tex_gray);
1334 glTextureStorage3D(tex_gray, levels, GL_R8, width1, height1, 2);
1336 GrayscaleConversion gray;
1337 gray.exec(image_tex, tex_gray, width1, height1, /*num_layers=*/2);
1338 glGenerateTextureMipmap(tex_gray);
1340 DISComputeFlow compute_flow(width1, height1);
1342 if (enable_warmup) {
1344 for (int i = 0; i < 10; ++i) {
1345 GLuint final_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD, DISComputeFlow::RESIZE_FLOW_TO_FULL_SIZE);
1346 compute_flow.release_texture(final_tex);
1351 GLuint final_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD, DISComputeFlow::RESIZE_FLOW_TO_FULL_SIZE);
1352 //GLuint final_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD_AND_BACKWARD, DISComputeFlow::RESIZE_FLOW_TO_FULL_SIZE);
1354 schedule_read<FlowType>(final_tex, width1, height1, filename0, filename1, flow_filename, "flow.ppm");
1355 compute_flow.release_texture(final_tex);
1357 // See if there are more flows on the command line (ie., more than three arguments),
1358 // and if so, process them.
1359 int num_flows = (argc - optind) / 3;
1360 for (int i = 1; i < num_flows; ++i) {
1361 const char *filename0 = argv[optind + i * 3 + 0];
1362 const char *filename1 = argv[optind + i * 3 + 1];
1363 const char *flow_filename = argv[optind + i * 3 + 2];
1364 GLuint width, height;
1365 GLuint tex0 = load_texture(filename0, &width, &height, WITHOUT_MIPMAPS);
1366 if (width != width1 || height != height1) {
1367 fprintf(stderr, "%s: Image dimensions don't match (%dx%d versus %dx%d)\n",
1368 filename0, width, height, width1, height1);
1371 glCopyImageSubData(tex0, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 0, width1, height1, 1);
1372 glDeleteTextures(1, &tex0);
1374 GLuint tex1 = load_texture(filename1, &width, &height, WITHOUT_MIPMAPS);
1375 if (width != width1 || height != height1) {
1376 fprintf(stderr, "%s: Image dimensions don't match (%dx%d versus %dx%d)\n",
1377 filename1, width, height, width1, height1);
1380 glCopyImageSubData(tex1, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 1, width1, height1, 1);
1381 glDeleteTextures(1, &tex1);
1383 gray.exec(image_tex, tex_gray, width1, height1, /*num_layers=*/2);
1384 glGenerateTextureMipmap(tex_gray);
1386 GLuint final_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD, DISComputeFlow::RESIZE_FLOW_TO_FULL_SIZE);
1388 schedule_read<FlowType>(final_tex, width1, height1, filename0, filename1, flow_filename, "");
1389 compute_flow.release_texture(final_tex);
1391 glDeleteTextures(1, &tex_gray);
1393 while (!reads_in_progress.empty()) {
1394 finish_one_read<FlowType>(width1, height1);
1398 // Interpolate images based on
1400 // Herbst, Seitz, Baker: “Occlusion Reasoning for Temporal Interpolation
1401 // Using Optical Flow”
1403 // or at least a reasonable subset thereof. Unfinished.
1404 void interpolate_image(int argc, char **argv, int optind)
1406 const char *filename0 = argc >= (optind + 1) ? argv[optind] : "test1499.png";
1407 const char *filename1 = argc >= (optind + 2) ? argv[optind + 1] : "test1500.png";
1408 //const char *out_filename = argc >= (optind + 3) ? argv[optind + 2] : "interpolated.png";
1411 unsigned width1, height1, width2, height2;
1412 GLuint tex0 = load_texture(filename0, &width1, &height1, WITH_MIPMAPS);
1413 GLuint tex1 = load_texture(filename1, &width2, &height2, WITH_MIPMAPS);
1415 if (width1 != width2 || height1 != height2) {
1416 fprintf(stderr, "Image dimensions don't match (%dx%d versus %dx%d)\n",
1417 width1, height1, width2, height2);
1421 // Move them into an array texture, since that's how the rest of the code
1423 int levels = find_num_levels(width1, height1);
1425 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &image_tex);
1426 glTextureStorage3D(image_tex, levels, GL_RGBA8, width1, height1, 2);
1427 glCopyImageSubData(tex0, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 0, width1, height1, 1);
1428 glCopyImageSubData(tex1, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 1, width1, height1, 1);
1429 glDeleteTextures(1, &tex0);
1430 glDeleteTextures(1, &tex1);
1431 glGenerateTextureMipmap(image_tex);
1433 // Set up some PBOs to do asynchronous readback.
1435 glCreateBuffers(5, pbos);
1436 for (int i = 0; i < 5; ++i) {
1437 glNamedBufferData(pbos[i], width1 * height1 * 4 * sizeof(uint8_t), nullptr, GL_STREAM_READ);
1438 spare_pbos.push(pbos[i]);
1441 DISComputeFlow compute_flow(width1, height1);
1442 GrayscaleConversion gray;
1443 Interpolate interpolate(width1, height1, finest_level);
1446 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &tex_gray);
1447 glTextureStorage3D(tex_gray, levels, GL_R8, width1, height1, 2);
1448 gray.exec(image_tex, tex_gray, width1, height1, /*num_layers=*/2);
1449 glGenerateTextureMipmap(tex_gray);
1451 if (enable_warmup) {
1453 for (int i = 0; i < 10; ++i) {
1454 GLuint bidirectional_flow_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD_AND_BACKWARD, DISComputeFlow::DO_NOT_RESIZE_FLOW);
1455 GLuint interpolated_tex = interpolate.exec(image_tex, bidirectional_flow_tex, width1, height1, 0.5f);
1456 compute_flow.release_texture(bidirectional_flow_tex);
1457 interpolate.release_texture(interpolated_tex);
1462 GLuint bidirectional_flow_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD_AND_BACKWARD, DISComputeFlow::DO_NOT_RESIZE_FLOW);
1464 for (int frameno = 1; frameno < 60; ++frameno) {
1465 char ppm_filename[256];
1466 snprintf(ppm_filename, sizeof(ppm_filename), "interp%04d.ppm", frameno);
1468 float alpha = frameno / 60.0f;
1469 GLuint interpolated_tex = interpolate.exec(image_tex, bidirectional_flow_tex, width1, height1, alpha);
1471 schedule_read<RGBAType>(interpolated_tex, width1, height1, filename0, filename1, "", ppm_filename);
1472 interpolate.release_texture(interpolated_tex);
1475 while (!reads_in_progress.empty()) {
1476 finish_one_read<RGBAType>(width1, height1);
1480 int main(int argc, char **argv)
1482 static const option long_options[] = {
1483 { "smoothness-relative-weight", required_argument, 0, 's' }, // alpha.
1484 { "intensity-relative-weight", required_argument, 0, 'i' }, // delta.
1485 { "gradient-relative-weight", required_argument, 0, 'g' }, // gamma.
1486 { "disable-timing", no_argument, 0, 1000 },
1487 { "detailed-timing", no_argument, 0, 1003 },
1488 { "ignore-variational-refinement", no_argument, 0, 1001 }, // Still calculates it, just doesn't apply it.
1489 { "interpolate", no_argument, 0, 1002 },
1490 { "warmup", no_argument, 0, 1004 }
1494 int option_index = 0;
1495 int c = getopt_long(argc, argv, "s:i:g:", long_options, &option_index);
1502 vr_alpha = atof(optarg);
1505 vr_delta = atof(optarg);
1508 vr_gamma = atof(optarg);
1511 enable_timing = false;
1514 enable_variational_refinement = false;
1517 enable_interpolation = true;
1520 detailed_timing = true;
1523 enable_warmup = true;
1526 fprintf(stderr, "Unknown option '%s'\n", argv[option_index]);
1531 if (SDL_Init(SDL_INIT_EVERYTHING) == -1) {
1532 fprintf(stderr, "SDL_Init failed: %s\n", SDL_GetError());
1535 SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);
1536 SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 0);
1537 SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0);
1538 SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
1540 SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
1541 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 4);
1542 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 5);
1543 // SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG);
1544 window = SDL_CreateWindow("OpenGL window",
1545 SDL_WINDOWPOS_UNDEFINED,
1546 SDL_WINDOWPOS_UNDEFINED,
1548 SDL_WINDOW_OPENGL | SDL_WINDOW_HIDDEN);
1549 SDL_GLContext context = SDL_GL_CreateContext(window);
1550 assert(context != nullptr);
1552 glDisable(GL_DITHER);
1554 // FIXME: Should be part of DISComputeFlow (but needs to be initialized
1555 // before all the render passes).
1556 float vertices[] = {
1562 glCreateBuffers(1, &vertex_vbo);
1563 glNamedBufferData(vertex_vbo, sizeof(vertices), vertices, GL_STATIC_DRAW);
1564 glBindBuffer(GL_ARRAY_BUFFER, vertex_vbo);
1566 if (enable_interpolation) {
1567 interpolate_image(argc, argv, optind);
1569 compute_flow_only(argc, argv, optind);