#define NO_SDL_GLEXT 1
-#define WIDTH 1280
-#define HEIGHT 720
-
#include <epoxy/gl.h>
#include <SDL2/SDL.h>
constexpr unsigned finest_level = 1;
constexpr unsigned patch_size_pixels = 12;
+// Weighting constants for the different parts of the variational refinement.
+// These don't correspond 1:1 to the values given in the DIS paper,
+// since we have different normalizations and ranges in some cases.
+float vr_gamma = 10.0f, vr_delta = 5.0f, vr_alpha = 10.0f;
+
// Some global OpenGL objects.
GLuint nearest_sampler, linear_sampler, smoothness_sampler;
GLuint vertex_vbo;
return obj;
}
-
-GLuint load_texture(const char *filename, unsigned width, unsigned height)
+GLuint load_texture(const char *filename, unsigned *width_ret, unsigned *height_ret)
{
- FILE *fp = fopen(filename, "rb");
- if (fp == nullptr) {
- perror(filename);
+ SDL_Surface *surf = IMG_Load(filename);
+ if (surf == nullptr) {
+ fprintf(stderr, "IMG_Load(%s): %s\n", filename, IMG_GetError());
exit(1);
}
- unique_ptr<uint8_t[]> pix(new uint8_t[width * height]);
- if (fread(pix.get(), width * height, 1, fp) != 1) {
- fprintf(stderr, "Short read from %s\n", filename);
+
+ // For whatever reason, SDL doesn't support converting to YUV surfaces
+ // nor grayscale, so we'll do it (slowly) ourselves.
+ SDL_Surface *rgb_surf = SDL_ConvertSurfaceFormat(surf, SDL_PIXELFORMAT_RGBA8888, /*flags=*/0);
+ if (rgb_surf == nullptr) {
+ fprintf(stderr, "SDL_ConvertSurfaceFormat(%s): %s\n", filename, SDL_GetError());
exit(1);
}
- fclose(fp);
- // Convert to bottom-left origin.
- for (unsigned y = 0; y < height / 2; ++y) {
+ SDL_FreeSurface(surf);
+
+ unsigned width = rgb_surf->w, height = rgb_surf->h;
+ const uint8_t *sptr = (uint8_t *)rgb_surf->pixels;
+ unique_ptr<uint8_t[]> pix(new uint8_t[width * height]);
+
+ // Extract the Y component, and convert to bottom-left origin.
+ for (unsigned y = 0; y < height; ++y) {
unsigned y2 = height - 1 - y;
- swap_ranges(&pix[y * width], &pix[y * width + width], &pix[y2 * width]);
+ for (unsigned x = 0; x < width; ++x) {
+ uint8_t r = sptr[(y2 * width + x) * 4 + 3];
+ uint8_t g = sptr[(y2 * width + x) * 4 + 2];
+ uint8_t b = sptr[(y2 * width + x) * 4 + 1];
+
+ // Rec. 709.
+ pix[y * width + x] = lrintf(r * 0.2126f + g * 0.7152f + b * 0.0722f);
+ }
}
+ SDL_FreeSurface(rgb_surf);
int levels = 1;
for (int w = width, h = height; w > 1 || h > 1; ) {
glTextureSubImage2D(tex, 0, 0, 0, width, height, GL_RED, GL_UNSIGNED_BYTE, pix.get());
glGenerateTextureMipmap(tex);
+ *width_ret = width;
+ *height_ret = height;
+
return tex;
}
GLuint smoothness_vao;
GLuint uniform_flow_tex, uniform_diff_flow_tex;
+ GLuint uniform_alpha;
};
ComputeSmoothness::ComputeSmoothness()
uniform_flow_tex = glGetUniformLocation(smoothness_program, "flow_tex");
uniform_diff_flow_tex = glGetUniformLocation(smoothness_program, "diff_flow_tex");
+ uniform_alpha = glGetUniformLocation(smoothness_program, "alpha");
}
void ComputeSmoothness::exec(GLuint flow_tex, GLuint diff_flow_tex, GLuint smoothness_x_tex, GLuint smoothness_y_tex, int level_width, int level_height)
bind_sampler(smoothness_program, uniform_flow_tex, 0, flow_tex, nearest_sampler);
bind_sampler(smoothness_program, uniform_diff_flow_tex, 1, diff_flow_tex, nearest_sampler);
+ glProgramUniform1f(smoothness_program, uniform_alpha, vr_alpha);
GLuint smoothness_fbo; // TODO: cleanup
glCreateFramebuffers(1, &smoothness_fbo);
GLuint uniform_diff_flow_tex, uniform_base_flow_tex;
GLuint uniform_beta_0_tex;
GLuint uniform_smoothness_x_tex, uniform_smoothness_y_tex;
+ GLuint uniform_gamma, uniform_delta;
};
SetupEquations::SetupEquations()
uniform_beta_0_tex = glGetUniformLocation(equations_program, "beta_0_tex");
uniform_smoothness_x_tex = glGetUniformLocation(equations_program, "smoothness_x_tex");
uniform_smoothness_y_tex = glGetUniformLocation(equations_program, "smoothness_y_tex");
+ uniform_gamma = glGetUniformLocation(equations_program, "gamma");
+ uniform_delta = glGetUniformLocation(equations_program, "delta");
}
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 smoothness_x_tex, GLuint smoothness_y_tex, GLuint equation_tex, int level_width, int level_height)
bind_sampler(equations_program, uniform_beta_0_tex, 4, beta_0_tex, nearest_sampler);
bind_sampler(equations_program, uniform_smoothness_x_tex, 5, smoothness_x_tex, smoothness_sampler);
bind_sampler(equations_program, uniform_smoothness_y_tex, 6, smoothness_y_tex, smoothness_sampler);
+ glProgramUniform1f(equations_program, uniform_delta, vr_delta);
+ glProgramUniform1f(equations_program, uniform_gamma, vr_gamma);
GLuint equations_fbo; // TODO: cleanup
glCreateFramebuffers(1, &equations_fbo);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
}
-// Calculate the smoothness constraints between neighboring pixels;
-// s_x(x,y) stores smoothness between pixel (x,y) and (x+1,y),
-// and s_y(x,y) stores between (x,y) and (x,y+1). We'll sample with
-// border color (0,0) later, so that there's zero diffusion out of
-// the border.
+// Actually solve the equation sets made by SetupEquations, by means of
+// successive over-relaxation (SOR).
//
// See variational_refinement.txt for more information.
class SOR {
return timer.query;
}
+// Take a copy of the flow, bilinearly interpolated and scaled up.
+class ResizeFlow {
+public:
+ ResizeFlow();
+ void exec(GLuint in_tex, GLuint out_tex, int input_width, int input_height, int output_width, int output_height);
+
+private:
+ GLuint resize_flow_vs_obj;
+ GLuint resize_flow_fs_obj;
+ GLuint resize_flow_program;
+ GLuint resize_flow_vao;
+
+ GLuint uniform_flow_tex;
+ GLuint uniform_scale_factor;
+};
+
+ResizeFlow::ResizeFlow()
+{
+ resize_flow_vs_obj = compile_shader(read_file("vs.vert"), GL_VERTEX_SHADER);
+ resize_flow_fs_obj = compile_shader(read_file("resize_flow.frag"), GL_FRAGMENT_SHADER);
+ resize_flow_program = link_program(resize_flow_vs_obj, resize_flow_fs_obj);
+
+ // Set up the VAO containing all the required position/texcoord data.
+ glCreateVertexArrays(1, &resize_flow_vao);
+ glBindVertexArray(resize_flow_vao);
+ glBindBuffer(GL_ARRAY_BUFFER, vertex_vbo);
+
+ GLint position_attrib = glGetAttribLocation(resize_flow_program, "position");
+ glEnableVertexArrayAttrib(resize_flow_vao, position_attrib);
+ glVertexAttribPointer(position_attrib, 2, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(0));
+
+ uniform_flow_tex = glGetUniformLocation(resize_flow_program, "flow_tex");
+ uniform_scale_factor = glGetUniformLocation(resize_flow_program, "scale_factor");
+}
+
+void ResizeFlow::exec(GLuint flow_tex, GLuint out_tex, int input_width, int input_height, int output_width, int output_height)
+{
+ glUseProgram(resize_flow_program);
+
+ bind_sampler(resize_flow_program, uniform_flow_tex, 0, flow_tex, nearest_sampler);
+
+ glProgramUniform2f(resize_flow_program, uniform_scale_factor, float(output_width) / input_width, float(output_height) / input_height);
+
+ GLuint resize_flow_fbo; // TODO: cleanup
+ glCreateFramebuffers(1, &resize_flow_fbo);
+ glNamedFramebufferTexture(resize_flow_fbo, GL_COLOR_ATTACHMENT0, out_tex, 0);
+
+ glViewport(0, 0, output_width, output_height);
+ glDisable(GL_BLEND);
+ glBindVertexArray(resize_flow_vao);
+ glBindFramebuffer(GL_FRAMEBUFFER, resize_flow_fbo);
+
+ glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+}
+
void GPUTimers::print()
{
for (const Timer &timer : timers) {
for (int i = 0; i < timer.level * 2; ++i) {
fprintf(stderr, " ");
}
- fprintf(stderr, "%-30s %4.1f ms\n", timer.name.c_str(), (time_end - time_start) / 1e6);
+ fprintf(stderr, "%-30s %4.1f ms\n", timer.name.c_str(), GLint64(time_end - time_start) / 1e6);
}
}
bool ended = false;
};
-int main(void)
+int main(int argc, char **argv)
{
if (SDL_Init(SDL_INIT_EVERYTHING) == -1) {
fprintf(stderr, "SDL_Init failed: %s\n", SDL_GetError());
assert(context != nullptr);
// Load pictures.
- GLuint tex0 = load_texture("test1499.pgm", WIDTH, HEIGHT);
- GLuint tex1 = load_texture("test1500.pgm", WIDTH, HEIGHT);
+ unsigned width1, height1, width2, height2;
+ GLuint tex0 = load_texture(argc >= 2 ? argv[1] : "test1499.png", &width1, &height1);
+ GLuint tex1 = load_texture(argc >= 3 ? argv[2] : "test1500.png", &width2, &height2);
+
+ if (width1 != width2 || height1 != height2) {
+ fprintf(stderr, "Image dimensions don't match (%dx%d versus %dx%d)\n",
+ width1, height1, width2, height2);
+ exit(1);
+ }
// Make some samplers.
glCreateSamplers(1, &nearest_sampler);
GLuint initial_flow_tex;
glCreateTextures(GL_TEXTURE_2D, 1, &initial_flow_tex);
glTextureStorage2D(initial_flow_tex, 1, GL_RG16F, 1, 1);
+ glClearTexImage(initial_flow_tex, 0, GL_RG, GL_FLOAT, nullptr);
int prev_level_width = 1, prev_level_height = 1;
GLuint prev_level_flow_tex = initial_flow_tex;
SetupEquations setup_equations;
SOR sor;
AddBaseFlow add_base_flow;
+ ResizeFlow resize_flow;
GLuint query;
glGenQueries(1, &query);
snprintf(timer_name, sizeof(timer_name), "Level %d", level);
ScopedTimer level_timer(timer_name, &total_timer);
- int level_width = WIDTH >> level;
- int level_height = HEIGHT >> level;
+ int level_width = width1 >> level;
+ int level_height = height1 >> level;
float patch_spacing_pixels = patch_size_pixels * (1.0f - patch_overlap_ratio);
int width_patches = 1 + lrintf((level_width - patch_size_pixels) / patch_spacing_pixels);
int height_patches = 1 + lrintf((level_height - patch_size_pixels) / patch_spacing_pixels);
// Add the differential flow found by the variational refinement to the base flow,
// giving the final flow estimate for this level.
// The output is in diff_flow_tex; we don't need to make a new texture.
- // You can comment out this prat if you wish to test disabling of the variational refinement.
+ // You can comment out this part if you wish to test disabling of the variational refinement.
{
ScopedTimer timer("Add differential flow", &varref_timer);
add_base_flow.exec(base_flow_tex, du_dv_tex, level_width, level_height);
timers.print();
- int level_width = WIDTH >> finest_level;
- int level_height = HEIGHT >> finest_level;
- unique_ptr<float[]> dense_flow(new float[level_width * level_height * 2]);
- glGetTextureImage(prev_level_flow_tex, 0, GL_RG, GL_FLOAT, level_width * level_height * 2 * sizeof(float), dense_flow.get());
+ // Scale up the flow to the final size (if needed).
+ GLuint final_tex;
+ if (finest_level == 0) {
+ final_tex = prev_level_flow_tex;
+ } else {
+ glCreateTextures(GL_TEXTURE_2D, 1, &final_tex);
+ glTextureStorage2D(final_tex, 1, GL_RG16F, width1, height1);
+ resize_flow.exec(prev_level_flow_tex, final_tex, prev_level_width, prev_level_height, width1, height1);
+ }
+
+ unique_ptr<float[]> dense_flow(new float[width1 * height1 * 2]);
+ glGetTextureImage(final_tex, 0, GL_RG, GL_FLOAT, width1 * height1 * 2 * sizeof(float), dense_flow.get());
FILE *fp = fopen("flow.ppm", "wb");
FILE *flowfp = fopen("flow.flo", "wb");
- fprintf(fp, "P6\n%d %d\n255\n", level_width, level_height);
+ fprintf(fp, "P6\n%d %d\n255\n", width1, height1);
fprintf(flowfp, "FEIH");
- fwrite(&level_width, 4, 1, flowfp);
- fwrite(&level_height, 4, 1, flowfp);
- for (unsigned y = 0; y < unsigned(level_height); ++y) {
- int yy = level_height - y - 1;
- for (unsigned x = 0; x < unsigned(level_width); ++x) {
- float du = dense_flow[(yy * level_width + x) * 2 + 0];
- float dv = dense_flow[(yy * level_width + x) * 2 + 1];
+ fwrite(&width1, 4, 1, flowfp);
+ fwrite(&height1, 4, 1, flowfp);
+ for (unsigned y = 0; y < unsigned(height1); ++y) {
+ int yy = height1 - y - 1;
+ for (unsigned x = 0; x < unsigned(width1); ++x) {
+ float du = dense_flow[(yy * width1 + x) * 2 + 0];
+ float dv = dense_flow[(yy * width1 + x) * 2 + 1];
dv = -dv;
projects / nageru / blobdiff