Add file switching, async histogram load

CMakeLists.txt

@@ -1,7 +1,8 @@
 cmake_minimum_required(VERSION 3.10)
 
+
 if(NOT CMAKE_BUILD_TYPE)
-  set(CMAKE_BUILD_TYPE Release)
+  set(CMAKE_BUILD_TYPE Debug)
 endif()
 
 set(CMAKE_CXX_STANDARD 20)
@@ -48,11 +49,13 @@ set(OpenGL_GL_PREFERENCE GLVND)
 find_package(SDL2 REQUIRED)
 find_package(OpenGL REQUIRED)
 find_package(exiv2 REQUIRED)
-include_directories(${SDL2_INCLUDE_DIRS} ${OPENGL_INCLUDE_DIRS})
+find_package(PkgConfig REQUIRED)
+pkg_check_modules(LIBRAW REQUIRED libraw)
+include_directories(${SDL2_INCLUDE_DIRS} ${OPENGL_INCLUDE_DIRS} ${LIBRAW_INCLUDE_DIRS})
 
 set(CMAKE_CXX_FLAGS "-Wall -Wextra")
-set(CMAKE_CXX_FLAGS_DEBUG "-g")
+set(CMAKE_CXX_FLAGS_DEBUG "-g3 -rdynamic -O0")
 set(CMAKE_CXX_FLAGS_RELEASE "-O2")
 
 add_executable(tview ${SOURCES})
-target_link_libraries(tview ${SDL2_LIBRARIES} ${OPENGL_LIBRARIES} exiv2lib)
+target_link_libraries(tview ${SDL2_LIBRARIES} ${OPENGL_LIBRARIES} exiv2lib ${LIBRAW_LIBRARIES})

main.cpp

@@ -1,6 +1,9 @@
 #include <SDL2/SDL_events.h>
 #include <SDL2/SDL_scancode.h>
 #include <cstddef>
+#include <map>
+#include <string>
+
 
 #include "lib/backends/imgui_impl_opengl3.h"
 #include "lib/backends/imgui_impl_sdl2.h"
@@ -12,9 +15,11 @@
 #include <iostream>
 #include <stdexcept>
 #include <stdio.h>
+#include <fstream>
 
 #define STB_IMAGE_IMPLEMENTATION
 #include "lib/stb_image.h"
+#include <libraw/libraw.h>
 
 #if defined(__APPLE__)
 #include <SDL2/SDL.h>
@@ -39,15 +44,18 @@
 #include <exiv2/exiv2.hpp>
 
 #include "lib/histogram.h"
-
+#include <future>
-
+#include <vector>
-
+#include <filesystem>
+#include <algorithm>
+#include <execinfo.h>
+#include <signal.h>
 struct Args : public argparse::Args {
   std::string &fpath = arg("path to the image");
 };
 
-
 struct EXIFData {
+  std::map<std::string, std::string> all_fields;
   std::string CameraMake;
   std::string CameraModel;
   std::string LensModel;
@@ -78,7 +86,106 @@ struct Texture
     EXIFData exif;
 };
 
+enum class DetectedFileType
+{
+    RAW,
+    JPEG,
+    PNG,
+    TIFF,
+    UNKNOWN
+};
+
+void handler(int sig) {
+  void *array[10];
+  size_t size;
+
+  // get void*'s for all entries on the stack
+  size = backtrace(array, 10);
+
+  // print out all the frames to stderr
+  fprintf(stderr, "Error: signal %d:\n", sig);
+  backtrace_symbols_fd(array, size, STDERR_FILENO);
+  exit(1);
+}
+
 static uint8_t* image = nullptr;
+static std::vector<std::string> image_files;
+static int current_image_index = -1;
+
+static DetectedFileType detectFileType(const std::string &filePath)
+{
+    std::ifstream file(filePath, std::ios::binary);
+    if (!file)
+        return DetectedFileType::UNKNOWN;
+
+    unsigned char magic[12]; // Read enough bytes for common signatures
+    file.read(reinterpret_cast<char *>(magic), sizeof(magic));
+    if (!file)
+        return DetectedFileType::UNKNOWN;
+
+    // Check common signatures
+    if (magic[0] == 0xFF && magic[1] == 0xD8 && magic[2] == 0xFF)
+        return DetectedFileType::JPEG;
+    if (magic[0] == 0x89 && magic[1] == 'P' && magic[2] == 'N' && magic[3] == 'G')
+        return DetectedFileType::PNG;
+    if ((magic[0] == 'I' && magic[1] == 'I' && magic[2] == 0x2A && magic[3] == 0x00) || // Little-endian TIFF
+        (magic[0] == 'M' && magic[1] == 'M' && magic[2] == 0x00 && magic[3] == 0x2A))   // Big-endian TIFF
+    {
+
+        size_t dotPos = filePath.rfind('.');
+        if (dotPos != std::string::npos)
+        {
+            std::string ext = filePath.substr(dotPos);
+            std::transform(ext.begin(), ext.end(), ext.begin(), ::tolower);
+
+            // Common RAW formats that use TIFF structure
+            const char *rawTiffExtensions[] = {
+                ".nef", // Nikon
+                ".cr2", // Canon
+                ".dng", // Adobe/Various
+                ".arw", // Sony
+                ".srw", // Samsung
+                ".orf", // Olympus
+                ".pef", // Pentax
+                ".raf", // Fuji
+                ".rw2"  // Panasonic
+            };
+
+            for (const char *rawExt : rawTiffExtensions)
+            {
+                if (ext == rawExt)
+                    return DetectedFileType::RAW;
+            }
+        }
+        return DetectedFileType::TIFF;
+    }
+
+    // If no standard signature matches, check extension for RAW as a fallback
+    // (LibRaw handles many internal variations)
+    size_t dotPos = filePath.rfind('.');
+    if (dotPos != std::string::npos)
+    {
+        std::string ext = filePath.substr(dotPos);
+        std::transform(ext.begin(), ext.end(), ext.begin(), ::tolower);
+        const char *rawExtensions[] = {
+            ".3fr", ".ari", ".arw", ".bay", ".braw", ".crw", ".cr2", ".cr3", ".cap",
+            ".data", ".dcs", ".dcr", ".dng", ".drf", ".eip", ".erf", ".fff", ".gpr",
+            ".iiq", ".k25", ".kdc", ".mdc", ".mef", ".mos", ".mrw", ".nef", ".nrw",
+            ".obm", ".orf", ".pef", ".ptx", ".pxn", ".r3d", ".raf", ".raw", ".rwl",
+            ".rw2", ".rwz", ".sr2", ".srf", ".srw", ".tif", ".x3f" // Note: .tif can be RAW or regular TIFF
+        };
+        for (const char *rawExt : rawExtensions)
+        {
+            if (ext == rawExt)
+                return DetectedFileType::RAW;
+        }
+        // Special case: Leica .dng can also be loaded by LibRaw
+        if (ext == ".dng")
+            return DetectedFileType::RAW;
+    }
+
+    return DetectedFileType::UNKNOWN;
+}
 
 
 EXIFData printExifData(const std::string& imagePath) {
@@ -104,6 +211,10 @@ EXIFData printExifData(const std::string& imagePath) {
             return d;
         }
 
+        for (auto i = exifData.begin(); i != exifData.end(); ++i) {
+          d.all_fields[i->key()] = i->value().toString();
+        }
+
         // Helper function to print EXIF data if available
         auto printExifValue = [&exifData](const char* key, std::string *d) {
             Exiv2::ExifKey exifKey(key);
@@ -173,8 +284,6 @@ Exif.GPSInfo.GPSLongitude                    0x0004 Rational    3  73/1 59/1 166
   return d;
 }
 
-
-
 Texture ReloadTexture(Texture tin, int width, int height) {
     GLuint tid = (GLuint)(uintptr_t)tin.texture;
     glDeleteTextures((GLsizei)1, &tid);
@@ -225,10 +334,53 @@ Texture LoadImage(const char * path) {
     const int channelCount = 4;
     int imageFileChannelCount;
     int width, height;
-    image = (uint8_t *)stbi_load(path, &width, &height, &imageFileChannelCount, channelCount);
+
-    if (image == NULL) {
+    // Detect File type
-        fprintf(stderr, "%s\nFailed to open %s\n", stbi_failure_reason(), path);
+    DetectedFileType fileType = detectFileType(path);
-        return {nullptr,{0,0}};
+
+    if (fileType == DetectedFileType::RAW) {
+        LibRaw iProcessor;
+        iProcessor.open_file(path);
+        iProcessor.unpack();
+        iProcessor.imgdata.params.use_camera_wb = 1;
+        iProcessor.dcraw_process();
+
+        libraw_processed_image_t *processed_image = iProcessor.dcraw_make_mem_image();
+        if (processed_image == NULL) {
+            fprintf(stderr, "Failed to process RAW file %s\n", path);
+            return {nullptr,{0,0}};
+        }
+
+        width = processed_image->width;
+        height = processed_image->height;
+        imageFileChannelCount = processed_image->colors;
+
+        image = new uint8_t[width * height * channelCount];
+        
+        if (processed_image->bits == 16) {
+            for (int i = 0; i < width * height; ++i) {
+                image[i * channelCount + 0] = processed_image->data[i * imageFileChannelCount + 0] / 256;
+                image[i * channelCount + 1] = processed_image->data[i * imageFileChannelCount + 1] / 256;
+                image[i * channelCount + 2] = processed_image->data[i * imageFileChannelCount + 2] / 256;
+                image[i * channelCount + 3] = 255; // Alpha channel
+            }
+        } else { // 8-bit
+            for (int i = 0; i < width * height; ++i) {
+                image[i * channelCount + 0] = processed_image->data[i * imageFileChannelCount + 0];
+                image[i * channelCount + 1] = processed_image->data[i * imageFileChannelCount + 1];
+                image[i * channelCount + 2] = processed_image->data[i * imageFileChannelCount + 2];
+                image[i * channelCount + 3] = 255; // Alpha channel
+            }
+        }
+        
+        iProcessor.dcraw_clear_mem(processed_image);
+
+    } else {
+      image = (uint8_t *)stbi_load(path, &width, &height, &imageFileChannelCount, channelCount);
+      if (image == NULL) {
+          fprintf(stderr, "%s\nFailed to open %s\n", stbi_failure_reason(), path);
+          return {nullptr,{0,0}};
+      }
     }
     auto exif = printExifData(path);
 
@@ -273,16 +425,18 @@ Texture LoadTexture(Texture tin) {
 }
 
 
-
 const int MAX_ANNOATED_TEXELS = 10000;
 
 // Main code
 int main(int argc, char* argv[]) {
+  signal(SIGSEGV, handler);
   Texture t;
+  std::string current_fpath;
 
   try {
     auto args = argparse::parse<Args>(argc, argv, true);
-    t = LoadImage(args.fpath.c_str());
+    current_fpath = args.fpath;
+    t = LoadImage(current_fpath.c_str());
     if (t.texture == nullptr) {
       std::cerr << "failed load image" << std::endl;
       return -1;
@@ -291,6 +445,21 @@ int main(int argc, char* argv[]) {
     std::cerr << "failed to parse arguments: " << e.what() << std::endl;
     return -1;
   }
+
+  std::filesystem::path p(current_fpath);
+  auto parent_path = p.parent_path();
+  for (const auto& entry : std::filesystem::directory_iterator(parent_path)) {
+      if (entry.is_regular_file()) {
+          if (detectFileType(entry.path().string()) != DetectedFileType::UNKNOWN) {
+              image_files.push_back(entry.path().string());
+          }
+      }
+  }
+  std::sort(image_files.begin(), image_files.end());
+  auto it = std::find(image_files.begin(), image_files.end(), current_fpath);
+  if (it != image_files.end()) {
+      current_image_index = std::distance(image_files.begin(), it);
+  }
   // Setup SDL
   if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_TIMER | SDL_INIT_GAMECONTROLLER) !=
       0) {
@@ -305,6 +474,8 @@ int main(int argc, char* argv[]) {
   bool SHOW_EXIF = false;
   bool SHOW_HISTOGRAM = false;
   int MODE = 0;
+  bool histogram_ready = false;
+  std::future<Texture> image_load_future;
 
   // Decide GL+GLSL versions
 #if defined(IMGUI_IMPL_OPENGL_ES2)
@@ -363,11 +534,15 @@ int main(int argc, char* argv[]) {
   SDL_GLContext gl_context = SDL_GL_CreateContext(window);
   SDL_GL_MakeCurrent(window, gl_context);
   SDL_GL_SetSwapInterval(1); // Enable vsync
+  
 
   // Setup Dear ImGui context
   IMGUI_CHECKVERSION();
+  
+
   ImGui::CreateContext();
   ImGuiIO &io = ImGui::GetIO();
+  ImGui::GetIO().IniFilename = NULL;
   (void)io;
   io.ConfigFlags |=
       ImGuiConfigFlags_NavEnableKeyboard;           // Enable Keyboard Controls
@@ -384,12 +559,31 @@ int main(int argc, char* argv[]) {
 
   t = LoadTexture(t);
   Histogram histogram = Histogram(t.size.x, t.size.y, t.channels);
-  histogram.Load(image);
+  auto histogram_future = std::async(std::launch::async, [&]() {
+    histogram.Load(image);
+    histogram_ready = true;
+  });
 
   // Main loop
   bool done = false;
   while (!done)
   {
+    if (image_load_future.valid()) {
+        auto status = image_load_future.wait_for(std::chrono::seconds(0));
+        if (status == std::future_status::ready) {
+            auto new_texture_data = image_load_future.get();
+            GLuint textureID = (GLuint)(uintptr_t)t.texture;
+            glDeleteTextures(1, &textureID);
+            t = new_texture_data;
+            t = LoadTexture(t);
+            histogram = Histogram(t.size.x, t.size.y, t.channels);
+            histogram_ready = false;
+            histogram_future = std::async(std::launch::async, [&]() {
+                histogram.Load(image);
+                histogram_ready = true;
+            });
+        }
+    }
 
     // Poll and handle events (inputs, window resize, etc.)
     SDL_Event event;
@@ -402,11 +596,11 @@ int main(int argc, char* argv[]) {
 
       switch (event.type) {
         case SDL_QUIT:
-          done = true;
+
-          break;
         case SDL_KEYDOWN:
         switch (event.key.keysym.scancode) {
             case SDL_SCANCODE_G:
+
               GRID_ENABLED = !GRID_ENABLED;
               break;
             case SDL_SCANCODE_T:
@@ -434,8 +628,33 @@ int main(int argc, char* argv[]) {
             case SDL_SCANCODE_C:
               SHOW_HISTOGRAM = !SHOW_HISTOGRAM;
               break;
+            case SDL_SCANCODE_LEFT:
+                if (current_image_index > 0) {
+                    current_image_index--;
+                } else {
+                    current_image_index = image_files.size() - 1;
+                }
+                if (!image_load_future.valid() || image_load_future.wait_for(std::chrono::seconds(0)) == std::future_status::ready) {
+                    image_load_future = std::async(std::launch::async, [&]() {
+                        return LoadImage(image_files[current_image_index].c_str());
+                    });
+                }
+                break;
+            case SDL_SCANCODE_RIGHT:
+                if (current_image_index < (int)image_files.size() - 1) {
+                    current_image_index++;
+                } else {
+                    current_image_index = 0;
+                }
+                if (!image_load_future.valid() || image_load_future.wait_for(std::chrono::seconds(0)) == std::future_status::ready) {
+                    image_load_future = std::async(std::launch::async, [&]() {
+                        return LoadImage(image_files[current_image_index].c_str());
+                    });
+                }
+                break;
+
             default:
-              break;
+                break;
         }
       }
     }
@@ -554,121 +773,145 @@ int main(int argc, char* argv[]) {
         topmost.ClassId = ImHashStr("TopMost");
         topmost.ViewportFlagsOverrideSet = ImGuiViewportFlags_TopMost;
         ImGui::SetNextWindowClass(&topmost);
-        ImGui::Begin("EXIF", NULL, ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_AlwaysAutoResize  | ImGuiWindowFlags_NoFocusOnAppearing);
+        ImGui::SetNextWindowSize(ImVec2(600, 600), ImGuiCond_FirstUseEver);
-        if(ImGui::BeginTable("Hardware", 2)) {
+        ImGui::Begin("EXIF", NULL, ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoFocusOnAppearing);
+        if(ImGui::BeginTable("Hardware", 2, ImGuiTableFlags_Resizable)) {
+          ImGui::TableSetupColumn("Field", ImGuiTableColumnFlags_WidthFixed, ImGuiTableColumnFlags_NoHide, 150.0f);
+          ImGui::TableSetupColumn("Value", ImGuiTableColumnFlags_WidthStretch);
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Make");
+          ImGui::TextWrapped("Make");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.CameraMake.c_str());
+          ImGui::TextWrapped("%s", t.exif.CameraMake.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Model");
+          ImGui::TextWrapped("Model");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.CameraModel.c_str());
+          ImGui::TextWrapped("%s", t.exif.CameraModel.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Lens");
+          ImGui::TextWrapped("Lens");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.LensModel.c_str());
+          ImGui::TextWrapped("%s", t.exif.LensModel.c_str());
 
           ImGui::EndTable();
         }
 
         ImGui::Separator();
 
-        if(ImGui::BeginTable("Photo", 2)) {
+        if(ImGui::BeginTable("Photo", 2, ImGuiTableFlags_Resizable)) {
+          ImGui::TableSetupColumn("Field", ImGuiTableColumnFlags_WidthFixed, ImGuiTableColumnFlags_NoHide, 150.0f);
+          ImGui::TableSetupColumn("Value", ImGuiTableColumnFlags_WidthStretch);
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Shutter Speed");
+          ImGui::TextWrapped("Shutter Speed");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ShutterSpeed.c_str());
+          ImGui::TextWrapped("%s", t.exif.ShutterSpeed.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("F-Stop");
+          ImGui::TextWrapped("F-Stop");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.FNumber.c_str());
+          ImGui::TextWrapped("%s", t.exif.FNumber.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("ISO");
+          ImGui::TextWrapped("ISO");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ISO.c_str());
+          ImGui::TextWrapped("%s", t.exif.ISO.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Focal Length");
+          ImGui::TextWrapped("Focal Length");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.FocalLength.c_str());
+          ImGui::TextWrapped("%s", t.exif.FocalLength.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Exposure Comp");
+          ImGui::TextWrapped("Exposure Comp");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ExposureBias.c_str());
+          ImGui::TextWrapped("%s", t.exif.ExposureBias.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Metering Mode");
+          ImGui::TextWrapped("Metering Mode");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.MeteringMode.c_str());
+          ImGui::TextWrapped("%s", t.exif.MeteringMode.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Flash");
+          ImGui::TextWrapped("Flash");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.Flash.c_str());
+          ImGui::TextWrapped("%s", t.exif.Flash.c_str());
 
           ImGui::EndTable();
         }
 
         ImGui::Separator();
 
-        if(ImGui::BeginTable("Meta", 2)) {
+        if(ImGui::BeginTable("Meta", 2, ImGuiTableFlags_Resizable)) {
+          ImGui::TableSetupColumn("Field", ImGuiTableColumnFlags_WidthFixed, ImGuiTableColumnFlags_NoHide, 150.0f);
+          ImGui::TableSetupColumn("Value", ImGuiTableColumnFlags_WidthStretch);
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Date");
+          ImGui::TextWrapped("Date");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s %s", t.exif.TimeTaken.c_str(), t.exif.TimeTakenOffset.c_str());
+          ImGui::TextWrapped("%s %s", t.exif.TimeTaken.c_str(), t.exif.TimeTakenOffset.c_str());
 
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Dimensions");
+          ImGui::TextWrapped("Dimensions");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%sx%s", t.exif.ImageDimensionX.c_str(), t.exif.ImageDimensiony.c_str());
+          ImGui::TextWrapped("%sx%s", t.exif.ImageDimensionX.c_str(), t.exif.ImageDimensiony.c_str());
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Orientation");
+          ImGui::TextWrapped("Orientation");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ImageOrientation.c_str());
+          ImGui::TextWrapped("%s", t.exif.ImageOrientation.c_str());
 
           ImGui::EndTable();
         }
 
         ImGui::Separator();
 
-        if(ImGui::BeginTable("Location", 2)) {
+        if(ImGui::BeginTable("Location", 2, ImGuiTableFlags_Resizable)) {
+          ImGui::TableSetupColumn("Field", ImGuiTableColumnFlags_WidthFixed, ImGuiTableColumnFlags_NoHide, 150.0f);
+          ImGui::TableSetupColumn("Value", ImGuiTableColumnFlags_WidthStretch);
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Latitude");
+          ImGui::TextWrapped("Latitude");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s %s", t.exif.GPSLat.c_str(), t.exif.GPSLatref.c_str());
+          ImGui::TextWrapped("%s %s", t.exif.GPSLat.c_str(), t.exif.GPSLatref.c_str());
 
 
           ImGui::TableNextRow();
           ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Longitude");
+          ImGui::TextWrapped("Longitude");
           ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s %s", t.exif.GPSLon.c_str(), t.exif.GPSLonref.c_str());
+          ImGui::TextWrapped("%s %s", t.exif.GPSLon.c_str(), t.exif.GPSLonref.c_str());
 
           ImGui::EndTable();
         }
 
+        ImGui::Separator();
+        if(ImGui::BeginTable("All EXIF", 2, ImGuiTableFlags_Resizable)) {
+          ImGui::TableSetupColumn("Field", ImGuiTableColumnFlags_WidthFixed, ImGuiTableColumnFlags_NoHide, 150.0f);
+          ImGui::TableSetupColumn("Value", ImGuiTableColumnFlags_WidthStretch);
+          for (auto const& [key, val] : t.exif.all_fields)
+          {
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("%s", key.c_str());
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", val.c_str());
+          }
+          ImGui::EndTable();
+        }
+
         ImGui::Separator();
         ImGui::Text("Press e to hide");
 
@@ -682,9 +925,13 @@ int main(int argc, char* argv[]) {
         topmost.ViewportFlagsOverrideSet = ImGuiViewportFlags_TopMost;
         ImGui::SetNextWindowClass(&topmost);
         ImGui::Begin("Histogram", NULL, ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_AlwaysAutoResize  | ImGuiWindowFlags_NoFocusOnAppearing);
-        histogram.Draw();
+        if (histogram_ready) {
-        ImGui::Separator();
+          histogram.Draw();
-        ImGui::Text("Press c to hide");
+          ImGui::Separator();
+          ImGui::Text("Press c to hide");
+        } else {
+          ImGui::Text("Loading...");
+        }
 
         ImGui::End();
       }