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 // Weighting constants for the different parts of the variational refinement.
36 // These don't correspond 1:1 to the values given in the DIS paper,
37 // since we have different normalizations and ranges in some cases.
38 // These are found through a simple grid search on some MPI-Sintel data,
39 // although the error (EPE) seems to be fairly insensitive to the precise values.
40 // Only the relative values matter, so we fix alpha (the smoothness constant)
41 // at unity and tweak the others.
42 static float vr_alpha = 1.0f, vr_delta = 0.25f, vr_gamma = 0.25f;
44 bool enable_timing = true;
45 bool detailed_timing = false;
46 bool enable_warmup = false;
47 bool in_warmup = false;
48 bool enable_variational_refinement = true; // Just for debugging.
49 bool enable_interpolation = false;
51 // Some global OpenGL objects.
52 // TODO: These should really be part of DISComputeFlow.
53 GLuint nearest_sampler, linear_sampler, zero_border_sampler;
56 // Structures for asynchronous readback. We assume everything is the same size (and GL_RG16F).
57 struct ReadInProgress {
59 string filename0, filename1;
60 string flow_filename, ppm_filename; // Either may be empty for no write.
62 stack<GLuint> spare_pbos;
63 deque<ReadInProgress> reads_in_progress;
65 int find_num_levels(int width, int height)
68 for (int w = width, h = height; w > 1 || h > 1; ) {
76 string read_file(const string &filename)
78 FILE *fp = fopen(filename.c_str(), "r");
80 perror(filename.c_str());
84 int ret = fseek(fp, 0, SEEK_END);
86 perror("fseek(SEEK_END)");
92 ret = fseek(fp, 0, SEEK_SET);
94 perror("fseek(SEEK_SET)");
100 ret = fread(&str[0], size, 1, fp);
106 fprintf(stderr, "Short read when trying to read %d bytes from %s\n",
107 size, filename.c_str());
116 GLuint compile_shader(const string &shader_src, GLenum type)
118 GLuint obj = glCreateShader(type);
119 const GLchar* source[] = { shader_src.data() };
120 const GLint length[] = { (GLint)shader_src.size() };
121 glShaderSource(obj, 1, source, length);
122 glCompileShader(obj);
124 GLchar info_log[4096];
125 GLsizei log_length = sizeof(info_log) - 1;
126 glGetShaderInfoLog(obj, log_length, &log_length, info_log);
127 info_log[log_length] = 0;
128 if (strlen(info_log) > 0) {
129 fprintf(stderr, "Shader compile log: %s\n", info_log);
133 glGetShaderiv(obj, GL_COMPILE_STATUS, &status);
134 if (status == GL_FALSE) {
135 // Add some line numbers to easier identify compile errors.
136 string src_with_lines = "/* 1 */ ";
138 for (char ch : shader_src) {
139 src_with_lines.push_back(ch);
142 snprintf(buf, sizeof(buf), "/* %3zu */ ", ++lineno);
143 src_with_lines += buf;
147 fprintf(stderr, "Failed to compile shader:\n%s\n", src_with_lines.c_str());
159 GLuint load_texture(const char *filename, unsigned *width_ret, unsigned *height_ret, MipmapPolicy mipmaps)
161 SDL_Surface *surf = IMG_Load(filename);
162 if (surf == nullptr) {
163 fprintf(stderr, "IMG_Load(%s): %s\n", filename, IMG_GetError());
167 // For whatever reason, SDL doesn't support converting to YUV surfaces
168 // nor grayscale, so we'll do it ourselves.
169 SDL_Surface *rgb_surf = SDL_ConvertSurfaceFormat(surf, SDL_PIXELFORMAT_RGBA32, /*flags=*/0);
170 if (rgb_surf == nullptr) {
171 fprintf(stderr, "SDL_ConvertSurfaceFormat(%s): %s\n", filename, SDL_GetError());
175 SDL_FreeSurface(surf);
177 unsigned width = rgb_surf->w, height = rgb_surf->h;
178 const uint8_t *sptr = (uint8_t *)rgb_surf->pixels;
179 unique_ptr<uint8_t[]> pix(new uint8_t[width * height * 4]);
181 // Extract the Y component, and convert to bottom-left origin.
182 for (unsigned y = 0; y < height; ++y) {
183 unsigned y2 = height - 1 - y;
184 memcpy(pix.get() + y * width * 4, sptr + y2 * rgb_surf->pitch, width * 4);
186 SDL_FreeSurface(rgb_surf);
188 int num_levels = (mipmaps == WITH_MIPMAPS) ? find_num_levels(width, height) : 1;
191 glCreateTextures(GL_TEXTURE_2D, 1, &tex);
192 glTextureStorage2D(tex, num_levels, GL_RGBA8, width, height);
193 glTextureSubImage2D(tex, 0, 0, 0, width, height, GL_RGBA, GL_UNSIGNED_BYTE, pix.get());
195 if (mipmaps == WITH_MIPMAPS) {
196 glGenerateTextureMipmap(tex);
200 *height_ret = height;
205 GLuint link_program(GLuint vs_obj, GLuint fs_obj)
207 GLuint program = glCreateProgram();
208 glAttachShader(program, vs_obj);
209 glAttachShader(program, fs_obj);
210 glLinkProgram(program);
212 glGetProgramiv(program, GL_LINK_STATUS, &success);
213 if (success == GL_FALSE) {
214 GLchar error_log[1024] = {0};
215 glGetProgramInfoLog(program, 1024, nullptr, error_log);
216 fprintf(stderr, "Error linking program: %s\n", error_log);
222 void bind_sampler(GLuint program, GLint location, GLuint texture_unit, GLuint tex, GLuint sampler)
224 if (location == -1) {
228 glBindTextureUnit(texture_unit, tex);
229 glBindSampler(texture_unit, sampler);
230 glProgramUniform1i(program, location, texture_unit);
233 template<size_t num_elements>
234 void PersistentFBOSet<num_elements>::render_to(const array<GLuint, num_elements> &textures)
236 auto it = fbos.find(textures);
237 if (it != fbos.end()) {
238 glBindFramebuffer(GL_FRAMEBUFFER, it->second);
243 glCreateFramebuffers(1, &fbo);
244 GLenum bufs[num_elements];
245 for (size_t i = 0; i < num_elements; ++i) {
246 glNamedFramebufferTexture(fbo, GL_COLOR_ATTACHMENT0 + i, textures[i], 0);
247 bufs[i] = GL_COLOR_ATTACHMENT0 + i;
249 glNamedFramebufferDrawBuffers(fbo, num_elements, bufs);
251 fbos[textures] = fbo;
252 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
255 template<size_t num_elements>
256 void PersistentFBOSetWithDepth<num_elements>::render_to(GLuint depth_rb, const array<GLuint, num_elements> &textures)
258 auto key = make_pair(depth_rb, textures);
260 auto it = fbos.find(key);
261 if (it != fbos.end()) {
262 glBindFramebuffer(GL_FRAMEBUFFER, it->second);
267 glCreateFramebuffers(1, &fbo);
268 GLenum bufs[num_elements];
269 glNamedFramebufferRenderbuffer(fbo, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depth_rb);
270 for (size_t i = 0; i < num_elements; ++i) {
271 glNamedFramebufferTexture(fbo, GL_COLOR_ATTACHMENT0 + i, textures[i], 0);
272 bufs[i] = GL_COLOR_ATTACHMENT0 + i;
274 glNamedFramebufferDrawBuffers(fbo, num_elements, bufs);
277 glBindFramebuffer(GL_FRAMEBUFFER, fbo);
280 GrayscaleConversion::GrayscaleConversion()
282 gray_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
283 gray_fs_obj = compile_shader(read_file("gray.frag"), GL_FRAGMENT_SHADER);
284 gray_program = link_program(gray_vs_obj, gray_fs_obj);
286 // Set up the VAO containing all the required position/texcoord data.
287 glCreateVertexArrays(1, &gray_vao);
288 glBindVertexArray(gray_vao);
290 GLint position_attrib = glGetAttribLocation(gray_program, "position");
291 glEnableVertexArrayAttrib(gray_vao, position_attrib);
292 glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
294 uniform_tex = glGetUniformLocation(gray_program, "tex");
297 void GrayscaleConversion::exec(GLint tex, GLint gray_tex, int width, int height, int num_layers)
299 glUseProgram(gray_program);
300 bind_sampler(gray_program, uniform_tex, 0, tex, nearest_sampler);
302 glViewport(0, 0, width, height);
303 fbos.render_to(gray_tex);
304 glBindVertexArray(gray_vao);
306 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
311 sobel_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
312 sobel_fs_obj = compile_shader(read_file("sobel.frag"), GL_FRAGMENT_SHADER);
313 sobel_program = link_program(sobel_vs_obj, sobel_fs_obj);
315 uniform_tex = glGetUniformLocation(sobel_program, "tex");
318 void Sobel::exec(GLint tex_view, GLint grad_tex, int level_width, int level_height, int num_layers)
320 glUseProgram(sobel_program);
321 bind_sampler(sobel_program, uniform_tex, 0, tex_view, nearest_sampler);
323 glViewport(0, 0, level_width, level_height);
324 fbos.render_to(grad_tex);
326 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
329 MotionSearch::MotionSearch(const OperatingPoint &op)
332 motion_vs_obj = compile_shader(read_file("motion_search.vert"), GL_VERTEX_SHADER);
333 motion_fs_obj = compile_shader(read_file("motion_search.frag"), GL_FRAGMENT_SHADER);
334 motion_search_program = link_program(motion_vs_obj, motion_fs_obj);
336 uniform_inv_image_size = glGetUniformLocation(motion_search_program, "inv_image_size");
337 uniform_inv_prev_level_size = glGetUniformLocation(motion_search_program, "inv_prev_level_size");
338 uniform_out_flow_size = glGetUniformLocation(motion_search_program, "out_flow_size");
339 uniform_image_tex = glGetUniformLocation(motion_search_program, "image_tex");
340 uniform_grad_tex = glGetUniformLocation(motion_search_program, "grad_tex");
341 uniform_flow_tex = glGetUniformLocation(motion_search_program, "flow_tex");
342 uniform_patch_size = glGetUniformLocation(motion_search_program, "patch_size");
343 uniform_num_iterations = glGetUniformLocation(motion_search_program, "num_iterations");
346 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)
348 glUseProgram(motion_search_program);
350 bind_sampler(motion_search_program, uniform_image_tex, 0, tex_view, linear_sampler);
351 bind_sampler(motion_search_program, uniform_grad_tex, 1, grad_tex, nearest_sampler);
352 bind_sampler(motion_search_program, uniform_flow_tex, 2, flow_tex, linear_sampler);
354 glProgramUniform2f(motion_search_program, uniform_inv_image_size, 1.0f / level_width, 1.0f / level_height);
355 glProgramUniform2f(motion_search_program, uniform_inv_prev_level_size, 1.0f / prev_level_width, 1.0f / prev_level_height);
356 glProgramUniform2f(motion_search_program, uniform_out_flow_size, width_patches, height_patches);
357 glProgramUniform1ui(motion_search_program, uniform_patch_size, op.patch_size_pixels);
358 glProgramUniform1ui(motion_search_program, uniform_num_iterations, op.search_iterations);
360 glViewport(0, 0, width_patches, height_patches);
361 fbos.render_to(flow_out_tex);
362 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, num_layers);
365 Densify::Densify(const OperatingPoint &op)
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(op.patch_size_pixels) / level_width,
386 float(op.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, const OperatingPoint &op)
617 : width(width), height(height), op(op), motion_search(op), densify(op)
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 = op.coarsest_level; level >= int(op.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 = op.patch_size_pixels * (1.0f - op.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 (op.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 (op.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);
845 Splat::Splat(const OperatingPoint &op)
848 splat_vs_obj = compile_shader(read_file("splat.vert"), GL_VERTEX_SHADER);
849 splat_fs_obj = compile_shader(read_file("splat.frag"), GL_FRAGMENT_SHADER);
850 splat_program = link_program(splat_vs_obj, splat_fs_obj);
852 uniform_splat_size = glGetUniformLocation(splat_program, "splat_size");
853 uniform_alpha = glGetUniformLocation(splat_program, "alpha");
854 uniform_image_tex = glGetUniformLocation(splat_program, "image_tex");
855 uniform_flow_tex = glGetUniformLocation(splat_program, "flow_tex");
856 uniform_inv_flow_size = glGetUniformLocation(splat_program, "inv_flow_size");
859 void Splat::exec(GLuint image_tex, GLuint bidirectional_flow_tex, GLuint flow_tex, GLuint depth_rb, int width, int height, float alpha)
861 glUseProgram(splat_program);
863 bind_sampler(splat_program, uniform_image_tex, 0, image_tex, linear_sampler);
864 bind_sampler(splat_program, uniform_flow_tex, 1, bidirectional_flow_tex, nearest_sampler);
866 glProgramUniform2f(splat_program, uniform_splat_size, op.splat_size / width, op.splat_size / height);
867 glProgramUniform1f(splat_program, uniform_alpha, alpha);
868 glProgramUniform2f(splat_program, uniform_inv_flow_size, 1.0f / width, 1.0f / height);
870 glViewport(0, 0, width, height);
872 glEnable(GL_DEPTH_TEST);
873 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.)
875 fbos.render_to(depth_rb, flow_tex);
877 // Evidently NVIDIA doesn't use fast clears for glClearTexImage, so clear now that
878 // we've got it bound.
879 glClearColor(1000.0f, 1000.0f, 0.0f, 1.0f); // Invalid flow.
880 glClearDepth(1.0f); // Effectively infinity.
881 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
883 glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, width * height * 2);
885 glDisable(GL_DEPTH_TEST);
890 fill_vs_obj = compile_shader(read_file("hole_fill.vert"), GL_VERTEX_SHADER);
891 fill_fs_obj = compile_shader(read_file("hole_fill.frag"), GL_FRAGMENT_SHADER);
892 fill_program = link_program(fill_vs_obj, fill_fs_obj);
894 uniform_tex = glGetUniformLocation(fill_program, "tex");
895 uniform_z = glGetUniformLocation(fill_program, "z");
896 uniform_sample_offset = glGetUniformLocation(fill_program, "sample_offset");
899 void HoleFill::exec(GLuint flow_tex, GLuint depth_rb, GLuint temp_tex[3], int width, int height)
901 glUseProgram(fill_program);
903 bind_sampler(fill_program, uniform_tex, 0, flow_tex, nearest_sampler);
905 glProgramUniform1f(fill_program, uniform_z, 1.0f - 1.0f / 1024.0f);
907 glViewport(0, 0, width, height);
909 glEnable(GL_DEPTH_TEST);
910 glDepthFunc(GL_LESS); // Only update the values > 0.999f (ie., only invalid pixels).
912 fbos.render_to(depth_rb, flow_tex); // NOTE: Reading and writing to the same texture.
914 // Fill holes from the left, by shifting 1, 2, 4, 8, etc. pixels to the right.
915 for (int offs = 1; offs < width; offs *= 2) {
916 glProgramUniform2f(fill_program, uniform_sample_offset, -offs / float(width), 0.0f);
917 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
920 glCopyImageSubData(flow_tex, GL_TEXTURE_2D, 0, 0, 0, 0, temp_tex[0], GL_TEXTURE_2D, 0, 0, 0, 0, width, height, 1);
922 // Similar to the right; adjust Z a bit down, so that we re-fill the pixels that
923 // were overwritten in the last algorithm.
924 glProgramUniform1f(fill_program, uniform_z, 1.0f - 2.0f / 1024.0f);
925 for (int offs = 1; offs < width; offs *= 2) {
926 glProgramUniform2f(fill_program, uniform_sample_offset, offs / float(width), 0.0f);
927 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
930 glCopyImageSubData(flow_tex, GL_TEXTURE_2D, 0, 0, 0, 0, temp_tex[1], GL_TEXTURE_2D, 0, 0, 0, 0, width, height, 1);
933 glProgramUniform1f(fill_program, uniform_z, 1.0f - 3.0f / 1024.0f);
934 for (int offs = 1; offs < height; offs *= 2) {
935 glProgramUniform2f(fill_program, uniform_sample_offset, 0.0f, -offs / float(height));
936 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
939 glCopyImageSubData(flow_tex, GL_TEXTURE_2D, 0, 0, 0, 0, temp_tex[2], GL_TEXTURE_2D, 0, 0, 0, 0, width, height, 1);
942 glProgramUniform1f(fill_program, uniform_z, 1.0f - 4.0f / 1024.0f);
943 for (int offs = 1; offs < height; offs *= 2) {
944 glProgramUniform2f(fill_program, uniform_sample_offset, 0.0f, offs / float(height));
945 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
949 glDisable(GL_DEPTH_TEST);
952 HoleBlend::HoleBlend()
954 blend_vs_obj = compile_shader(read_file("hole_fill.vert"), GL_VERTEX_SHADER); // Reuse the vertex shader from the fill.
955 blend_fs_obj = compile_shader(read_file("hole_blend.frag"), GL_FRAGMENT_SHADER);
956 blend_program = link_program(blend_vs_obj, blend_fs_obj);
958 uniform_left_tex = glGetUniformLocation(blend_program, "left_tex");
959 uniform_right_tex = glGetUniformLocation(blend_program, "right_tex");
960 uniform_up_tex = glGetUniformLocation(blend_program, "up_tex");
961 uniform_down_tex = glGetUniformLocation(blend_program, "down_tex");
962 uniform_z = glGetUniformLocation(blend_program, "z");
963 uniform_sample_offset = glGetUniformLocation(blend_program, "sample_offset");
966 void HoleBlend::exec(GLuint flow_tex, GLuint depth_rb, GLuint temp_tex[3], int width, int height)
968 glUseProgram(blend_program);
970 bind_sampler(blend_program, uniform_left_tex, 0, temp_tex[0], nearest_sampler);
971 bind_sampler(blend_program, uniform_right_tex, 1, temp_tex[1], nearest_sampler);
972 bind_sampler(blend_program, uniform_up_tex, 2, temp_tex[2], nearest_sampler);
973 bind_sampler(blend_program, uniform_down_tex, 3, flow_tex, nearest_sampler);
975 glProgramUniform1f(blend_program, uniform_z, 1.0f - 4.0f / 1024.0f);
976 glProgramUniform2f(blend_program, uniform_sample_offset, 0.0f, 0.0f);
978 glViewport(0, 0, width, height);
980 glEnable(GL_DEPTH_TEST);
981 glDepthFunc(GL_LEQUAL); // Skip over all of the pixels that were never holes to begin with.
983 fbos.render_to(depth_rb, flow_tex); // NOTE: Reading and writing to the same texture.
985 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
987 glDisable(GL_DEPTH_TEST);
992 blend_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
993 blend_fs_obj = compile_shader(read_file("blend.frag"), GL_FRAGMENT_SHADER);
994 blend_program = link_program(blend_vs_obj, blend_fs_obj);
996 uniform_image_tex = glGetUniformLocation(blend_program, "image_tex");
997 uniform_flow_tex = glGetUniformLocation(blend_program, "flow_tex");
998 uniform_alpha = glGetUniformLocation(blend_program, "alpha");
999 uniform_flow_consistency_tolerance = glGetUniformLocation(blend_program, "flow_consistency_tolerance");
1002 void Blend::exec(GLuint image_tex, GLuint flow_tex, GLuint output_tex, int level_width, int level_height, float alpha)
1004 glUseProgram(blend_program);
1005 bind_sampler(blend_program, uniform_image_tex, 0, image_tex, linear_sampler);
1006 bind_sampler(blend_program, uniform_flow_tex, 1, flow_tex, linear_sampler); // May be upsampled.
1007 glProgramUniform1f(blend_program, uniform_alpha, alpha);
1009 glViewport(0, 0, level_width, level_height);
1010 fbos.render_to(output_tex);
1011 glDisable(GL_BLEND); // A bit ironic, perhaps.
1012 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
1015 Interpolate::Interpolate(int width, int height, const OperatingPoint &op)
1016 : width(width), height(height), flow_level(op.finest_level), op(op), splat(op) {
1017 // Set up the vertex data that will be shared between all passes.
1018 float vertices[] = {
1024 glCreateBuffers(1, &vertex_vbo);
1025 glNamedBufferData(vertex_vbo, sizeof(vertices), vertices, GL_STATIC_DRAW);
1027 glCreateVertexArrays(1, &vao);
1028 glBindVertexArray(vao);
1029 glBindBuffer(GL_ARRAY_BUFFER, vertex_vbo);
1031 GLint position_attrib = 0; // Hard-coded in every vertex shader.
1032 glEnableVertexArrayAttrib(vao, position_attrib);
1033 glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
1036 GLuint Interpolate::exec(GLuint image_tex, GLuint bidirectional_flow_tex, GLuint width, GLuint height, float alpha)
1040 ScopedTimer total_timer("Interpolate", &timers);
1042 glBindVertexArray(vao);
1044 // Pick out the right level to test splatting results on.
1046 glGenTextures(1, &tex_view);
1047 glTextureView(tex_view, GL_TEXTURE_2D_ARRAY, image_tex, GL_RGBA8, flow_level, 1, 0, 2);
1049 int flow_width = width >> flow_level;
1050 int flow_height = height >> flow_level;
1052 GLuint flow_tex = pool.get_texture(GL_RG16F, flow_width, flow_height);
1053 GLuint depth_rb = pool.get_renderbuffer(GL_DEPTH_COMPONENT16, flow_width, flow_height); // Used for ranking flows.
1056 ScopedTimer timer("Splat", &total_timer);
1057 splat.exec(tex_view, bidirectional_flow_tex, flow_tex, depth_rb, flow_width, flow_height, alpha);
1059 glDeleteTextures(1, &tex_view);
1062 temp_tex[0] = pool.get_texture(GL_RG16F, flow_width, flow_height);
1063 temp_tex[1] = pool.get_texture(GL_RG16F, flow_width, flow_height);
1064 temp_tex[2] = pool.get_texture(GL_RG16F, flow_width, flow_height);
1067 ScopedTimer timer("Fill holes", &total_timer);
1068 hole_fill.exec(flow_tex, depth_rb, temp_tex, flow_width, flow_height);
1069 hole_blend.exec(flow_tex, depth_rb, temp_tex, flow_width, flow_height);
1072 pool.release_texture(temp_tex[0]);
1073 pool.release_texture(temp_tex[1]);
1074 pool.release_texture(temp_tex[2]);
1075 pool.release_renderbuffer(depth_rb);
1077 GLuint output_tex = pool.get_texture(GL_RGBA8, width, height);
1079 ScopedTimer timer("Blend", &total_timer);
1080 blend.exec(image_tex, flow_tex, output_tex, width, height, alpha);
1082 pool.release_texture(flow_tex);
1091 GLuint TexturePool::get_texture(GLenum format, GLuint width, GLuint height, GLuint num_layers)
1093 for (Texture &tex : textures) {
1094 if (!tex.in_use && !tex.is_renderbuffer && tex.format == format &&
1095 tex.width == width && tex.height == height && tex.num_layers == num_layers) {
1102 if (num_layers == 0) {
1103 glCreateTextures(GL_TEXTURE_2D, 1, &tex.tex_num);
1104 glTextureStorage2D(tex.tex_num, 1, format, width, height);
1106 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &tex.tex_num);
1107 glTextureStorage3D(tex.tex_num, 1, format, width, height, num_layers);
1109 tex.format = format;
1111 tex.height = height;
1112 tex.num_layers = num_layers;
1114 tex.is_renderbuffer = false;
1115 textures.push_back(tex);
1119 GLuint TexturePool::get_renderbuffer(GLenum format, GLuint width, GLuint height)
1121 for (Texture &tex : textures) {
1122 if (!tex.in_use && tex.is_renderbuffer && tex.format == format &&
1123 tex.width == width && tex.height == height) {
1130 glCreateRenderbuffers(1, &tex.tex_num);
1131 glNamedRenderbufferStorage(tex.tex_num, format, width, height);
1133 tex.format = format;
1135 tex.height = height;
1137 tex.is_renderbuffer = true;
1138 textures.push_back(tex);
1142 void TexturePool::release_texture(GLuint tex_num)
1144 for (Texture &tex : textures) {
1145 if (!tex.is_renderbuffer && tex.tex_num == tex_num) {
1154 void TexturePool::release_renderbuffer(GLuint tex_num)
1156 for (Texture &tex : textures) {
1157 if (tex.is_renderbuffer && tex.tex_num == tex_num) {
1166 // OpenGL uses a bottom-left coordinate system, .flo files use a top-left coordinate system.
1167 void flip_coordinate_system(float *dense_flow, unsigned width, unsigned height)
1169 for (unsigned i = 0; i < width * height; ++i) {
1170 dense_flow[i * 2 + 1] = -dense_flow[i * 2 + 1];
1174 // Not relevant for RGB.
1175 void flip_coordinate_system(uint8_t *dense_flow, unsigned width, unsigned height)
1179 void write_flow(const char *filename, const float *dense_flow, unsigned width, unsigned height)
1181 FILE *flowfp = fopen(filename, "wb");
1182 fprintf(flowfp, "FEIH");
1183 fwrite(&width, 4, 1, flowfp);
1184 fwrite(&height, 4, 1, flowfp);
1185 for (unsigned y = 0; y < height; ++y) {
1186 int yy = height - y - 1;
1187 fwrite(&dense_flow[yy * width * 2], width * 2 * sizeof(float), 1, flowfp);
1192 // Not relevant for RGB.
1193 void write_flow(const char *filename, const uint8_t *dense_flow, unsigned width, unsigned height)
1198 void write_ppm(const char *filename, const float *dense_flow, unsigned width, unsigned height)
1200 FILE *fp = fopen(filename, "wb");
1201 fprintf(fp, "P6\n%d %d\n255\n", width, height);
1202 for (unsigned y = 0; y < unsigned(height); ++y) {
1203 int yy = height - y - 1;
1204 for (unsigned x = 0; x < unsigned(width); ++x) {
1205 float du = dense_flow[(yy * width + x) * 2 + 0];
1206 float dv = dense_flow[(yy * width + x) * 2 + 1];
1209 flow2rgb(du, dv, &r, &g, &b);
1218 void write_ppm(const char *filename, const uint8_t *rgba, unsigned width, unsigned height)
1220 unique_ptr<uint8_t[]> rgb_line(new uint8_t[width * 3 + 1]);
1222 FILE *fp = fopen(filename, "wb");
1223 fprintf(fp, "P6\n%d %d\n255\n", width, height);
1224 for (unsigned y = 0; y < height; ++y) {
1225 unsigned y2 = height - 1 - y;
1226 for (size_t x = 0; x < width; ++x) {
1227 memcpy(&rgb_line[x * 3], &rgba[(y2 * width + x) * 4], 4);
1229 fwrite(rgb_line.get(), width * 3, 1, fp);
1236 static constexpr GLenum gl_format = GL_RG;
1237 static constexpr GLenum gl_type = GL_FLOAT;
1238 static constexpr int num_channels = 2;
1242 using type = uint8_t;
1243 static constexpr GLenum gl_format = GL_RGBA;
1244 static constexpr GLenum gl_type = GL_UNSIGNED_BYTE;
1245 static constexpr int num_channels = 4;
1248 template <class Type>
1249 void finish_one_read(GLuint width, GLuint height)
1251 using T = typename Type::type;
1252 constexpr int bytes_per_pixel = Type::num_channels * sizeof(T);
1254 assert(!reads_in_progress.empty());
1255 ReadInProgress read = reads_in_progress.front();
1256 reads_in_progress.pop_front();
1258 unique_ptr<T[]> flow(new typename Type::type[width * height * Type::num_channels]);
1259 void *buf = glMapNamedBufferRange(read.pbo, 0, width * height * bytes_per_pixel, GL_MAP_READ_BIT); // Blocks if the read isn't done yet.
1260 memcpy(flow.get(), buf, width * height * bytes_per_pixel); // TODO: Unneeded for RGBType, since flip_coordinate_system() does nothing.:
1261 glUnmapNamedBuffer(read.pbo);
1262 spare_pbos.push(read.pbo);
1264 flip_coordinate_system(flow.get(), width, height);
1265 if (!read.flow_filename.empty()) {
1266 write_flow(read.flow_filename.c_str(), flow.get(), width, height);
1267 fprintf(stderr, "%s %s -> %s\n", read.filename0.c_str(), read.filename1.c_str(), read.flow_filename.c_str());
1269 if (!read.ppm_filename.empty()) {
1270 write_ppm(read.ppm_filename.c_str(), flow.get(), width, height);
1274 template <class Type>
1275 void schedule_read(GLuint tex, GLuint width, GLuint height, const char *filename0, const char *filename1, const char *flow_filename, const char *ppm_filename)
1277 using T = typename Type::type;
1278 constexpr int bytes_per_pixel = Type::num_channels * sizeof(T);
1280 if (spare_pbos.empty()) {
1281 finish_one_read<Type>(width, height);
1283 assert(!spare_pbos.empty());
1284 reads_in_progress.emplace_back(ReadInProgress{ spare_pbos.top(), filename0, filename1, flow_filename, ppm_filename });
1285 glBindBuffer(GL_PIXEL_PACK_BUFFER, spare_pbos.top());
1287 glGetTextureImage(tex, 0, Type::gl_format, Type::gl_type, width * height * bytes_per_pixel, nullptr);
1288 glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
1291 void compute_flow_only(int argc, char **argv, int optind)
1293 const char *filename0 = argc >= (optind + 1) ? argv[optind] : "test1499.png";
1294 const char *filename1 = argc >= (optind + 2) ? argv[optind + 1] : "test1500.png";
1295 const char *flow_filename = argc >= (optind + 3) ? argv[optind + 2] : "flow.flo";
1298 unsigned width1, height1, width2, height2;
1299 GLuint tex0 = load_texture(filename0, &width1, &height1, WITHOUT_MIPMAPS);
1300 GLuint tex1 = load_texture(filename1, &width2, &height2, WITHOUT_MIPMAPS);
1302 if (width1 != width2 || height1 != height2) {
1303 fprintf(stderr, "Image dimensions don't match (%dx%d versus %dx%d)\n",
1304 width1, height1, width2, height2);
1308 // Move them into an array texture, since that's how the rest of the code
1311 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &image_tex);
1312 glTextureStorage3D(image_tex, 1, GL_RGBA8, width1, height1, 2);
1313 glCopyImageSubData(tex0, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 0, width1, height1, 1);
1314 glCopyImageSubData(tex1, GL_TEXTURE_2D, 0, 0, 0, 0, image_tex, GL_TEXTURE_2D_ARRAY, 0, 0, 0, 1, width1, height1, 1);
1315 glDeleteTextures(1, &tex0);
1316 glDeleteTextures(1, &tex1);
1318 // Set up some PBOs to do asynchronous readback.
1320 glCreateBuffers(5, pbos);
1321 for (int i = 0; i < 5; ++i) {
1322 glNamedBufferData(pbos[i], width1 * height1 * 2 * 2 * sizeof(float), nullptr, GL_STREAM_READ);
1323 spare_pbos.push(pbos[i]);
1326 int levels = find_num_levels(width1, height1);
1329 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &tex_gray);
1330 glTextureStorage3D(tex_gray, levels, GL_R8, width1, height1, 2);
1332 GrayscaleConversion gray;
1333 gray.exec(image_tex, tex_gray, width1, height1, /*num_layers=*/2);
1334 glGenerateTextureMipmap(tex_gray);
1336 OperatingPoint op = operating_point3;
1337 if (!enable_variational_refinement) {
1338 op.variational_refinement = false;
1340 DISComputeFlow compute_flow(width1, height1, op);
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 OperatingPoint op = operating_point3;
1442 if (!enable_variational_refinement) {
1443 op.variational_refinement = false;
1445 DISComputeFlow compute_flow(width1, height1, op);
1446 GrayscaleConversion gray;
1447 Interpolate interpolate(width1, height1, op);
1450 glCreateTextures(GL_TEXTURE_2D_ARRAY, 1, &tex_gray);
1451 glTextureStorage3D(tex_gray, levels, GL_R8, width1, height1, 2);
1452 gray.exec(image_tex, tex_gray, width1, height1, /*num_layers=*/2);
1453 glGenerateTextureMipmap(tex_gray);
1455 if (enable_warmup) {
1457 for (int i = 0; i < 10; ++i) {
1458 GLuint bidirectional_flow_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD_AND_BACKWARD, DISComputeFlow::DO_NOT_RESIZE_FLOW);
1459 GLuint interpolated_tex = interpolate.exec(image_tex, bidirectional_flow_tex, width1, height1, 0.5f);
1460 compute_flow.release_texture(bidirectional_flow_tex);
1461 interpolate.release_texture(interpolated_tex);
1466 GLuint bidirectional_flow_tex = compute_flow.exec(tex_gray, DISComputeFlow::FORWARD_AND_BACKWARD, DISComputeFlow::DO_NOT_RESIZE_FLOW);
1468 for (int frameno = 1; frameno < 60; ++frameno) {
1469 char ppm_filename[256];
1470 snprintf(ppm_filename, sizeof(ppm_filename), "interp%04d.ppm", frameno);
1472 float alpha = frameno / 60.0f;
1473 GLuint interpolated_tex = interpolate.exec(image_tex, bidirectional_flow_tex, width1, height1, alpha);
1475 schedule_read<RGBAType>(interpolated_tex, width1, height1, filename0, filename1, "", ppm_filename);
1476 interpolate.release_texture(interpolated_tex);
1479 while (!reads_in_progress.empty()) {
1480 finish_one_read<RGBAType>(width1, height1);
1484 int main(int argc, char **argv)
1486 static const option long_options[] = {
1487 { "smoothness-relative-weight", required_argument, 0, 's' }, // alpha.
1488 { "intensity-relative-weight", required_argument, 0, 'i' }, // delta.
1489 { "gradient-relative-weight", required_argument, 0, 'g' }, // gamma.
1490 { "disable-timing", no_argument, 0, 1000 },
1491 { "detailed-timing", no_argument, 0, 1003 },
1492 { "ignore-variational-refinement", no_argument, 0, 1001 }, // Still calculates it, just doesn't apply it.
1493 { "interpolate", no_argument, 0, 1002 },
1494 { "warmup", no_argument, 0, 1004 }
1498 int option_index = 0;
1499 int c = getopt_long(argc, argv, "s:i:g:", long_options, &option_index);
1506 vr_alpha = atof(optarg);
1509 vr_delta = atof(optarg);
1512 vr_gamma = atof(optarg);
1515 enable_timing = false;
1518 enable_variational_refinement = false;
1521 enable_interpolation = true;
1524 detailed_timing = true;
1527 enable_warmup = true;
1530 fprintf(stderr, "Unknown option '%s'\n", argv[option_index]);
1535 if (SDL_Init(SDL_INIT_EVERYTHING) == -1) {
1536 fprintf(stderr, "SDL_Init failed: %s\n", SDL_GetError());
1539 SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);
1540 SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 0);
1541 SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0);
1542 SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
1544 SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
1545 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 4);
1546 SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 5);
1547 // SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG);
1548 window = SDL_CreateWindow("OpenGL window",
1549 SDL_WINDOWPOS_UNDEFINED,
1550 SDL_WINDOWPOS_UNDEFINED,
1552 SDL_WINDOW_OPENGL | SDL_WINDOW_HIDDEN);
1553 SDL_GLContext context = SDL_GL_CreateContext(window);
1554 assert(context != nullptr);
1556 glDisable(GL_DITHER);
1558 // FIXME: Should be part of DISComputeFlow (but needs to be initialized
1559 // before all the render passes).
1560 float vertices[] = {
1566 glCreateBuffers(1, &vertex_vbo);
1567 glNamedBufferData(vertex_vbo, sizeof(vertices), vertices, GL_STATIC_DRAW);
1568 glBindBuffer(GL_ARRAY_BUFFER, vertex_vbo);
1570 if (enable_interpolation) {
1571 interpolate_image(argc, argv, optind);
1573 compute_flow_only(argc, argv, optind);