Fix YCbCrInput after the ResourcePool texture changes.
[movit] / ycbcr_input.cpp
index 8d58c7d..87140be 100644 (file)
@@ -1,9 +1,61 @@
-#include <string.h>
+#include <Eigen/Core>
+#include <Eigen/LU>
+#include <GL/glew.h>
 #include <assert.h>
+#include <stdio.h>
+#include <string.h>
 
-#include "ycbcr_input.h"
+#include "effect_util.h"
+#include "resource_pool.h"
 #include "util.h"
-#include "opengl.h"
+#include "ycbcr_input.h"
+
+using namespace Eigen;
+
+namespace {
+
+// OpenGL has texel center in (0.5, 0.5), but different formats have
+// chroma in various other places. If luma samples are X, the chroma
+// sample is *, and subsampling is 3x3, the situation with chroma
+// center in (0.5, 0.5) looks approximately like this:
+//
+//   X   X
+//     *   
+//   X   X
+//
+// If, on the other hand, chroma center is in (0.0, 0.5) (common
+// for e.g. MPEG-4), the figure changes to:
+//
+//   X   X
+//   *      
+//   X   X
+//
+// In other words, (0.0, 0.0) means that the chroma sample is exactly
+// co-sited on top of the top-left luma sample. Note, however, that
+// this is _not_ 0.5 texels to the left, since the OpenGL's texel center
+// is in (0.5, 0.5); it is in (0.25, 0.25). In a sense, the four luma samples
+// define a square where chroma position (0.0, 0.0) is in texel position
+// (0.25, 0.25) and chroma position (1.0, 1.0) is in texel position (0.75, 0.75)
+// (the outer border shows the borders of the texel itself, ie. from
+// (0, 0) to (1, 1)):
+//
+//  ---------
+// |         |
+// |  X---X  |
+// |  | * |  |
+// |  X---X  |
+// |         |
+//  ---------
+//
+// Also note that if we have no subsampling, the square will have zero
+// area and the chroma position does not matter at all.
+float compute_chroma_offset(float pos, unsigned subsampling_factor, unsigned resolution)
+{
+       float local_chroma_pos = (0.5 + pos * (subsampling_factor - 1)) / subsampling_factor;
+       return (0.5 - local_chroma_pos) / resolution;
+}
+
+}  // namespace
 
 YCbCrInput::YCbCrInput(const ImageFormat &image_format,
                        const YCbCrFormat &ycbcr_format,
@@ -11,7 +63,6 @@ YCbCrInput::YCbCrInput(const ImageFormat &image_format,
        : image_format(image_format),
          ycbcr_format(ycbcr_format),
          needs_update(false),
-         needs_pbo_recreate(false),
          finalized(false),
          needs_mipmaps(false),
          width(width),
@@ -20,65 +71,42 @@ YCbCrInput::YCbCrInput(const ImageFormat &image_format,
        pbos[0] = pbos[1] = pbos[2] = 0;
        texture_num[0] = texture_num[1] = texture_num[2] = 0;
 
-       pitch[0] = pitch[1] = pitch[2] = width;
-
        assert(width % ycbcr_format.chroma_subsampling_x == 0);
-       widths[0] = width;
-       widths[1] = width / ycbcr_format.chroma_subsampling_x;
-       widths[2] = width / ycbcr_format.chroma_subsampling_x;
+       pitch[0] = widths[0] = width;
+       pitch[1] = widths[1] = width / ycbcr_format.chroma_subsampling_x;
+       pitch[2] = widths[2] = width / ycbcr_format.chroma_subsampling_x;
 
        assert(height % ycbcr_format.chroma_subsampling_y == 0);
        heights[0] = height;
        heights[1] = height / ycbcr_format.chroma_subsampling_y;
        heights[2] = height / ycbcr_format.chroma_subsampling_y;
 
+       pixel_data[0] = pixel_data[1] = pixel_data[2] = NULL;
+
        register_int("needs_mipmaps", &needs_mipmaps);
 }
 
 YCbCrInput::~YCbCrInput()
 {
-       if (pbos[0] != 0) {
-               glDeleteBuffers(3, pbos);
-               check_error();
-       }
-       if (texture_num[0] != 0) {
-               glDeleteTextures(3, texture_num);
-               check_error();
+       for (unsigned channel = 0; channel < 3; ++channel) {
+               if (texture_num[channel] != 0) {
+                       resource_pool->release_2d_texture(texture_num[channel]);
+               }
        }
 }
 
 void YCbCrInput::finalize()
 {
-       glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
-       check_error();
-
-       // Create PBOs to hold the textures holding the input image, and then the texture itself.
-       glGenBuffers(3, pbos);
-       check_error();
-       glGenTextures(3, texture_num);
-       check_error();
-
+       // Create the textures themselves.
        for (unsigned channel = 0; channel < 3; ++channel) {
-               glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbos[channel]);
-               check_error();
-               glBufferData(GL_PIXEL_UNPACK_BUFFER_ARB, pitch[channel] * heights[channel], NULL, GL_STREAM_DRAW);
-               check_error();
-               glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
-               check_error();
-               
+               texture_num[channel] = resource_pool->create_2d_texture(GL_LUMINANCE8, widths[channel], heights[channel]);
                glBindTexture(GL_TEXTURE_2D, texture_num[channel]);
                check_error();
                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
                check_error();
-               glPixelStorei(GL_UNPACK_ROW_LENGTH, pitch[channel]);
-               check_error();
-               glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE8, widths[channel], heights[channel], 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, NULL);
-               check_error();
-               glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
-               check_error();
        }
 
-       needs_update = false;
+       needs_update = true;
        finalized = true;
 }
        
@@ -90,27 +118,16 @@ void YCbCrInput::set_gl_state(GLuint glsl_program_num, const std::string& prefix
                glBindTexture(GL_TEXTURE_2D, texture_num[channel]);
                check_error();
 
-               if (needs_update || needs_pbo_recreate) {
+               if (needs_update) {
+                       // Re-upload the texture.
                        // Copy the pixel data into the PBO.
                        glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, pbos[channel]);
                        check_error();
-
-                       if (needs_pbo_recreate) {
-                               // The pitch has changed; we need to reallocate this PBO.
-                               glBufferData(GL_PIXEL_UNPACK_BUFFER_ARB, pitch[channel] * heights[channel], NULL, GL_STREAM_DRAW);
-                               check_error();
-                       }
-
-                       void *mapped_pbo = glMapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB, GL_WRITE_ONLY);
-                       memcpy(mapped_pbo, pixel_data[channel], pitch[channel] * heights[channel]);
-
-                       glUnmapBufferARB(GL_PIXEL_UNPACK_BUFFER_ARB);
+                       glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
                        check_error();
-
-                       // Re-upload the texture from the PBO.
                        glPixelStorei(GL_UNPACK_ROW_LENGTH, pitch[channel]);
                        check_error();
-                       glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, widths[channel], heights[channel], GL_LUMINANCE, GL_UNSIGNED_BYTE, BUFFER_OFFSET(0));
+                       glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, widths[channel], heights[channel], GL_LUMINANCE, GL_UNSIGNED_BYTE, pixel_data[channel]);
                        check_error();
                        glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
                        check_error();
@@ -118,11 +135,12 @@ void YCbCrInput::set_gl_state(GLuint glsl_program_num, const std::string& prefix
                        check_error();
                        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
                        check_error();
-                       glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
-                       check_error();
                }
        }
 
+       glBindBuffer(GL_PIXEL_UNPACK_BUFFER_ARB, 0);
+       check_error();
+
        // Bind samplers.
        set_uniform_int(glsl_program_num, prefix, "tex_y", *sampler_num + 0);
        set_uniform_int(glsl_program_num, prefix, "tex_cb", *sampler_num + 1);
@@ -130,7 +148,6 @@ void YCbCrInput::set_gl_state(GLuint glsl_program_num, const std::string& prefix
 
        *sampler_num += 3;
        needs_update = false;
-       needs_pbo_recreate = false;
 }
 
 std::string YCbCrInput::output_fragment_shader()
@@ -151,6 +168,14 @@ std::string YCbCrInput::output_fragment_shader()
                coeff[1] = 0.7152;
                coeff[2] = 0.0722;
                break;
+
+       case YCBCR_REC_2020:
+               // Rec. 2020, page 4.
+               coeff[0] = 0.2627;
+               coeff[1] = 0.6780;
+               coeff[2] = 0.0593;
+               break;
+
        default:
                assert(false);
        }
@@ -164,7 +189,7 @@ std::string YCbCrInput::output_fragment_shader()
                scale[1] = 1.0;
                scale[2] = 1.0;
        } else {
-               // Rec. 601, page 4; Rec. 709, page 19.
+               // Rec. 601, page 4; Rec. 709, page 19; Rec. 2020, page 4.
                offset[0] = 16.0 / 255.0;
                offset[1] = 128.0 / 255.0;
                offset[2] = 128.0 / 255.0;
@@ -175,38 +200,29 @@ std::string YCbCrInput::output_fragment_shader()
        }
 
        // Matrix to convert RGB to YCbCr. See e.g. Rec. 601.
-       Matrix3x3 rgb_to_ycbcr;
-       rgb_to_ycbcr[0] = coeff[0];
-       rgb_to_ycbcr[3] = coeff[1];
-       rgb_to_ycbcr[6] = coeff[2];
+       Matrix3d rgb_to_ycbcr;
+       rgb_to_ycbcr(0,0) = coeff[0];
+       rgb_to_ycbcr(0,1) = coeff[1];
+       rgb_to_ycbcr(0,2) = coeff[2];
 
        float cb_fac = (224.0 / 219.0) / (coeff[0] + coeff[1] + 1.0f - coeff[2]);
-       rgb_to_ycbcr[1] = -coeff[0] * cb_fac;
-       rgb_to_ycbcr[4] = -coeff[1] * cb_fac;
-       rgb_to_ycbcr[7] = (1.0f - coeff[2]) * cb_fac;
+       rgb_to_ycbcr(1,0) = -coeff[0] * cb_fac;
+       rgb_to_ycbcr(1,1) = -coeff[1] * cb_fac;
+       rgb_to_ycbcr(1,2) = (1.0f - coeff[2]) * cb_fac;
 
        float cr_fac = (224.0 / 219.0) / (1.0f - coeff[0] + coeff[1] + coeff[2]);
-       rgb_to_ycbcr[2] = (1.0f - coeff[0]) * cr_fac;
-       rgb_to_ycbcr[5] = -coeff[1] * cr_fac;
-       rgb_to_ycbcr[8] = -coeff[2] * cr_fac;
+       rgb_to_ycbcr(2,0) = (1.0f - coeff[0]) * cr_fac;
+       rgb_to_ycbcr(2,1) = -coeff[1] * cr_fac;
+       rgb_to_ycbcr(2,2) = -coeff[2] * cr_fac;
 
        // Inverting the matrix gives us what we need to go from YCbCr back to RGB.
-       Matrix3x3 ycbcr_to_rgb;
-       invert_3x3_matrix(rgb_to_ycbcr, ycbcr_to_rgb);
+       Matrix3d ycbcr_to_rgb = rgb_to_ycbcr.inverse();
 
        std::string frag_shader;
 
-       char buf[1024];
-       sprintf(buf,
-               "const mat3 PREFIX(inv_ycbcr_matrix) = mat3(\n"
-               "    %.8f, %.8f, %.8f,\n"
-               "    %.8f, %.8f, %.8f,\n"
-               "    %.8f, %.8f, %.8f);\n",
-               ycbcr_to_rgb[0], ycbcr_to_rgb[1], ycbcr_to_rgb[2],
-               ycbcr_to_rgb[3], ycbcr_to_rgb[4], ycbcr_to_rgb[5],
-               ycbcr_to_rgb[6], ycbcr_to_rgb[7], ycbcr_to_rgb[8]);
-       frag_shader = buf;
+       frag_shader = output_glsl_mat3("PREFIX(inv_ycbcr_matrix)", ycbcr_to_rgb);
 
+       char buf[256];
        sprintf(buf, "const vec3 PREFIX(offset) = vec3(%.8f, %.8f, %.8f);\n",
                offset[0], offset[1], offset[2]);
        frag_shader += buf;
@@ -215,29 +231,20 @@ std::string YCbCrInput::output_fragment_shader()
                scale[0], scale[1], scale[2]);
        frag_shader += buf;
 
-       // OpenGL has texel center in (0.5, 0.5), but different formats have
-       // chroma in various other places. If luma samples are X, the chroma
-       // sample is *, and subsampling is 3x3, the situation with chroma
-       // center in (0.5, 0.5) looks approximately like this:
-       //
-       //   X     X
-       //      *   
-       //   X     X
-       //
-       // If, on the other hand, chroma center is in (0.0, 0.5) (common
-       // for e.g. MPEG-4), the figure changes to:
-       //
-       //   X     X
-       //   *      
-       //   X     X
-       //
-       // Obviously, the chroma plane here needs to be moved to the left,
-       // which means _adding_ 0.5 to the texture coordinates when sampling
-       // chroma.
-       float chroma_offset_x = (0.5f - ycbcr_format.chroma_x_position) / widths[1];
-       float chroma_offset_y = (0.5f - ycbcr_format.chroma_y_position) / heights[1];
-       sprintf(buf, "const vec2 PREFIX(chroma_offset) = vec2(%.8f, %.8f);\n",
-               chroma_offset_x, chroma_offset_y);
+       float cb_offset_x = compute_chroma_offset(
+               ycbcr_format.cb_x_position, ycbcr_format.chroma_subsampling_x, widths[1]);
+       float cb_offset_y = compute_chroma_offset(
+               ycbcr_format.cb_y_position, ycbcr_format.chroma_subsampling_y, heights[1]);
+       sprintf(buf, "const vec2 PREFIX(cb_offset) = vec2(%.8f, %.8f);\n",
+               cb_offset_x, cb_offset_y);
+       frag_shader += buf;
+
+       float cr_offset_x = compute_chroma_offset(
+               ycbcr_format.cr_x_position, ycbcr_format.chroma_subsampling_x, widths[2]);
+       float cr_offset_y = compute_chroma_offset(
+               ycbcr_format.cr_y_position, ycbcr_format.chroma_subsampling_y, heights[2]);
+       sprintf(buf, "const vec2 PREFIX(cr_offset) = vec2(%.8f, %.8f);\n",
+               cr_offset_x, cr_offset_y);
        frag_shader += buf;
 
        frag_shader += read_file("ycbcr_input.frag");