Background color change, better keybinds

.gitea/workflows/run_build.yaml

@@ -0,0 +1,43 @@
+name: Run Build
+run-name: ${{ gitea.actor }} is building tview
+on: [push]
+
+jobs:
+  run-build-arch:
+    container:
+      image: archlinux:multilib-devel
+    steps:
+    - name: Install dependencies
+      run: pacman -Sy --noconfirm sdl2 mesa-utils exiv2 cmake nodejs git && pacman -Syu --noconfirm
+    - name: Check out repository code
+      uses: actions/checkout@v4
+    - name: Run ls
+      run: ls
+    - name: Generate build files
+      run: cmake .
+    - name: Build
+      run: cmake --build .
+  run-build-ubuntu:
+    container:
+      image: ubuntu:24.04
+    steps:
+    - name: Install dependencies
+      run: apt update && apt install --no-install-recommends -y build-essential cmake libsdl2-dev libexiv2-dev mesa-utils nodejs ca-certificates git
+    - name: Check out repository code
+      uses: actions/checkout@v4
+    - name: Generate build files
+      run: cmake .
+    - name: Build
+      run: cmake --build .
+  run-build-debian:
+    container:
+      image: debian:bookworm
+    steps:
+    - name: Install dependencies
+      run: apt update && apt install --no-install-recommends -y build-essential cmake libsdl2-dev libexiv2-dev mesa-utils nodejs ca-certificates git
+    - name: Check out repository code
+      uses: actions/checkout@v4
+    - name: Generate build files
+      run: cmake .
+    - name: Build
+      run: cmake --build .

CMakeLists.txt

@@ -1,5 +1,10 @@
 cmake_minimum_required(VERSION 3.10)
 
+
+if(NOT CMAKE_BUILD_TYPE)
+  set(CMAKE_BUILD_TYPE Debug)
+endif()
+
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED True)
 
@@ -44,7 +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 "-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})

README.md

@@ -1,57 +1,93 @@
+# tview
+>  A (relatively) fast, lightweight, and useful image viewer.
 
-# How to Build
+![Main Image](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/main.png)
 
-## Windows with Visual Studio's IDE
+# Features
+- Supports most common image formats
+- EXIF Viewing
+- Histogram Calculation
+- Toggle image filtering
+- Pixel level details
+- Color tooltip
+# Gallery
+## Tooltip
+Toggle the tooltip by pressing `t`
+![Tooltip](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/tooltip.png)
 
-Use the provided project file (.vcxproj). Add to solution (imgui_examples.sln) if necessary.
+## Detail Views
+Toggle detail modes by pressing `d`
 
-## Windows with Visual Studio's CLI
+| Normal Arrow          | Hex Color           | RGB 255 Color           | RGB Float Color           |
+| --------------------- | ------------------- | ----------------------- | ------------------------- |
+| ![Normal Arrow](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/detail_arrow.png) | ![Hex](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/detail_hex.png) | ![RGB 255](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/detail_rgb_int.png) | ![RGB Float](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/detail_rgb_float.png) |
+## Image Filtering
+Toggle Filtering by pressing 
 
-Use build_win32.bat or directly:
+| Filtering Off          | Filtering On          |
+| ---------------------- | --------------------- |
+| ![Filtering Off](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/filtering_off.png) | ![Filtering On](https://git.dws.rip/dubey/tview/raw/branch/main/screenshots/filtering_on.png) |
+# Usage
+`tview PATH/TO/IMAGE`
+
+Press `h` to show the help dialog within the program.
+## Mouse
+Scroll to zoom.
+Click and drag to pan.
+
+## Keyboard
+- `h` - Show help
+- `c`- Toggle Histogram
+- `e`- Toggle EXIF data
+- `d`- Cycle [[#Detail Views]] (default off)
+- `a` - Toggle image filtering (default off)
+- `g` - Toggle grid (only visible at pixel level)
+- `r`- Rotate image 90 degrees clockwise
+- `q` - Quit
+
+# Installing
+## Requirements to Run
+- SDL2
+- OpenGL
+- Libexiv2
+
+## Requirements to build
+In addition to the run requirements
+- CMake
+- C++ Compiler (g++/clang++)
+### On Ubuntu
 ```
-set SDL2_DIR=path_to_your_sdl2_folder
+apt install --no-install-recommends build-essential cmake libsdl2-dev libexiv2-dev mesa-utils
-cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL2_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl2.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl2_opengl3.exe /FoDebug/ /link /libpath:%SDL2_DIR%\lib\x86 SDL2.lib SDL2main.lib opengl32.lib /subsystem:console
+```
-#                 ^^ include paths                  ^^ source files                                                                                    ^^ output exe                    ^^ output dir   ^^ libraries
+### On Debian
-# or for 64-bit:
+```
-cl /Zi /MD /utf-8 /I.. /I..\.. /I%SDL2_DIR%\include main.cpp ..\..\backends\imgui_impl_sdl2.cpp ..\..\backends\imgui_impl_opengl3.cpp ..\..\imgui*.cpp /FeDebug/example_sdl2_opengl3.exe /FoDebug/ /link /libpath:%SDL2_DIR%\lib\x64 SDL2.lib SDL2main.lib opengl32.lib /subsystem:console
+apt install --no-install-recommends build-essential cmake libsdl2-dev libexiv2-dev mesa-utils
+```
+### On Arch
+```
+pacman -Sy sdl2 mesa-utils exiv2 cmake base-devel
 ```
 
-## Linux and similar Unixes
+## Building
-
+Clone the repository
-Use our Makefile or directly:
 ```
-c++ `sdl2-config --cflags` -I .. -I ../.. -I ../../backends
+git clone https://git.dws.rip/dubey/tview.git
-  main.cpp ../../backends/imgui_impl_sdl2.cpp ../../backends/imgui_impl_opengl3.cpp ../../imgui*.cpp
-  `sdl2-config --libs` -lGL -ldl
 ```
 
-## macOS
+Change directory into the repository
-
-Use our Makefile or directly:
 ```
-brew install sdl2
+cd tview
-c++ `sdl2-config --cflags` -I .. -I ../.. -I ../../backends
-  main.cpp ../../backends/imgui_impl_sdl2.cpp ../../backends/imgui_impl_opengl3.cpp ../../imgui*.cpp
-  `sdl2-config --libs` -framework OpenGl -framework CoreFoundation
 ```
 
-## Emscripten
+Generate build files and trigger build
+```
+cmake .
+cmake --build .
+```
 
-**Building**
+You will now have a file called `tview` in the repository root, you can copy this into your path:
+```
+sudo mv ./tview /usr/local/bin/tview
+```
 
-You need to install Emscripten from https://emscripten.org/docs/getting_started/downloads.html, and have the environment variables set, as described in https://emscripten.org/docs/getting_started/downloads.html#installation-instructions
+`tview` is now installed on your system
-
-- Depending on your configuration, in Windows you may need to run `emsdk/emsdk_env.bat` in your console to access the Emscripten command-line tools.
-- You may also refer to our [Continuous Integration setup](https://github.com/ocornut/imgui/tree/master/.github/workflows) for Emscripten setup.
-- Then build using `make -f Makefile.emscripten` while in the current directory.
-
-**Running an Emscripten project**
-
-To run on a local machine:
-- `make -f Makefile.emscripten serve` will use Python3 to spawn a local webserver, you can then browse http://localhost:8000 to access your build.
-- Otherwise, generally you will need a local webserver. Quoting [https://emscripten.org/docs/getting_started](https://emscripten.org/docs/getting_started/Tutorial.html#generating-html):<br>
-_"Unfortunately several browsers (including Chrome, Safari, and Internet Explorer) do not support file:// [XHR](https://emscripten.org/docs/site/glossary.html#term-xhr) requests, and can’t load extra files needed by the HTML (like a .wasm file, or packaged file data as mentioned lower down). For these browsers you’ll need to serve the files using a [local webserver](https://emscripten.org/docs/getting_started/FAQ.html#faq-local-webserver) and then open http://localhost:8000/hello.html."_
-- Emscripten SDK has a handy `emrun` command: `emrun web/index.html --browser firefox` which will spawn a temporary local webserver (in Firefox). See https://emscripten.org/docs/compiling/Running-html-files-with-emrun.html for details.
-- You may use Python 3 builtin webserver: `python -m http.server -d web` (this is what `make serve` uses).
-- You may use Python 2 builtin webserver: `cd web && python -m SimpleHTTPServer`.
-- If you are accessing the files over a network, certain browsers, such as Firefox, will restrict Gamepad API access to secure contexts only (e.g. https only).

lib/imgui_tex_inspect.cpp

@@ -58,6 +58,7 @@ struct Context
     float                                       DefaultPanelHeight       = 600;  // Height of panel in pixels
     float                                       DefaultInitialPanelWidth = 600;  // Only applies when window first appears
     int                                         MaxAnnotations           = 1000; // Limit number of texel annotations for performance
+    float                                       InitialZoom              = 1.0f;
 };
 
 Context *GContext = nullptr;
@@ -191,7 +192,7 @@ bool BeginInspectorPanel(const char *title, ImTextureID texture, ImVec2 textureS
         }
         else if (justCreated)
         {
-            newScale = 1;
+            newScale = GContext->InitialZoom;
         }
 
         if (newScale != -1)
@@ -684,6 +685,11 @@ void SetZoomRate(float rate)
     GContext->ZoomRate = rate;
 }
 
+void SetInitialZoom(float zoom)
+{
+    GContext->InitialZoom = zoom;
+}
+
 //-------------------------------------------------------------------------
 // [SECTION] Life Cycle
 //-------------------------------------------------------------------------

lib/imgui_tex_inspect.h

@@ -32,7 +32,7 @@ enum InspectorAlphaMode
 typedef ImU64 InspectorFlags;
 enum InspectorFlags_
 {
-    InspectorFlags_ShowWrap             = 1 << 0,  // Draw beyong the [0,1] uv range. What you see will depend on API
+    InspectorFlags_ShowWrap             = 1 << 0,  // Draw beyond the [0,1] uv range. What you see will depend on API
     InspectorFlags_NoForceFilterNearest = 1 << 1,  // Normally we force nearest neighbour sampling when zoomed in. Set to disable this.
     InspectorFlags_NoGrid               = 1 << 2,  // By default a grid is shown at high zoom levels
     InspectorFlags_NoTooltip            = 1 << 3,  // Disable tooltip on hover
@@ -132,6 +132,7 @@ void DrawAlphaModeSelector();    // A combo box for selecting the alpha mode
  * scroll will increase zoom level by 50%. The factor used for zooming out is 
  * 1/factor. */
 void SetZoomRate(float factor); 
+void SetInitialZoom(float zoom);
                                 
 //-------------------------------------------------------------------------
 // [SECTION] ANNOTATION TOOLS

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"
@@ -8,12 +11,15 @@
 #include "lib/imgui_internal.h"
 #include <cstdint>
 #include <exiv2/tags.hpp>
+#include <exiv2/version.hpp>
 #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>
@@ -38,13 +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;
@@ -75,7 +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) {
@@ -83,7 +193,11 @@ EXIFData printExifData(const std::string& imagePath) {
     d.CameraMake = "NULL";
     try {
         // Load the image
+        #if EXIV2_TEST_VERSION(0,28,0)
         Exiv2::Image::UniquePtr img = Exiv2::ImageFactory::open(imagePath);
+        #else
+        Exiv2::Image::AutoPtr img = Exiv2::ImageFactory::open(imagePath);
+        #endif
         if (img.get() == 0) {
             std::cerr << "Error: Could not open image file " << imagePath << std::endl;
             return d;
@@ -97,6 +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);
@@ -166,8 +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);
@@ -218,10 +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);
 
@@ -266,16 +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;
@@ -284,6 +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) {
@@ -298,6 +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)
@@ -338,13 +516,25 @@ int main(int argc, char* argv[]) {
       (SDL_WindowFlags)(SDL_WINDOW_OPENGL | SDL_WINDOW_RESIZABLE |
                         SDL_WINDOW_ALLOW_HIGHDPI);
 
-
+  float image_w = t.size.x;
-  int wh = 800;
+  float image_h = t.size.y;
-  int ww = 1280;
+  if (t.exif.ImageOrientation == "6" || t.exif.ImageOrientation == "8") {
-  if (t.size.y > t.size.x) {
+    std::swap(image_w, image_h);
-    ww = 500;
-    wh = 1280;
   }
+
+  float aspect_ratio = image_w / image_h;
+  int viewer_h = image_h;
+  int viewer_w = image_w;
+  const int max_h = 1200;
+
+  if (viewer_h > max_h) {
+      viewer_h = max_h;
+      viewer_w = max_h * aspect_ratio;
+  }
+
+  int ww = viewer_w * 1.25;
+  int wh = viewer_h * 1.25;
+
   SDL_Window *window =
       SDL_CreateWindow("tview", SDL_WINDOWPOS_CENTERED,
                        SDL_WINDOWPOS_CENTERED, ww, wh, window_flags);
@@ -356,11 +546,15 @@ 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
@@ -372,17 +566,46 @@ int main(int argc, char* argv[]) {
   ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
   ImGui_ImplOpenGL3_Init(glsl_version);
 
-  ImVec4 clear_color = ImVec4(0.45f, 0.55f, 0.60f, 1.00f);
+  ImVec4 clear_color = ImVec4(0.18f, 0.18f, 0.18f, 1.00f);
+  std::vector<ImVec4> background_colors = {
+    ImVec4(0.0f, 0.0f, 0.0f, 1.00f),
+    ImVec4(0.18f, 0.18f, 0.18f, 1.00f),
+    ImVec4(0.5f, 0.5f, 0.5f, 1.00f),
+    ImVec4(255.0f, 255.0f, 255.0f, 255.00f),
+    ImVec4(0.75f, 0.75f, 0.75f, 1.00f)
+  };
+  int background_color_index = 1;
+
   auto flags = ImGuiTexInspect::InspectorFlags_FillVertical | ImGuiTexInspect::InspectorFlags_FillHorizontal;
 
   t = LoadTexture(t);
+  ImGuiTexInspect::SetInitialZoom(0.80f);
   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;
@@ -395,11 +618,11 @@ 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:
@@ -408,7 +631,7 @@ int main(int argc, char* argv[]) {
             case SDL_SCANCODE_A:
               AA_ENABLED = !AA_ENABLED;
               break;
-            case SDL_SCANCODE_H:
+            case SDL_SCANCODE_SLASH:
               SHOW_HELP = !SHOW_HELP;
               break;
             case SDL_SCANCODE_D:
@@ -424,11 +647,40 @@ int main(int argc, char* argv[]) {
             case SDL_SCANCODE_E:
               SHOW_EXIF = !SHOW_EXIF;
               break;
-            case SDL_SCANCODE_C:
+            case SDL_SCANCODE_H:
               SHOW_HISTOGRAM = !SHOW_HISTOGRAM;
               break;
-            default:
+            case SDL_SCANCODE_B:
+              background_color_index = (background_color_index + 1) % background_colors.size();
+              clear_color = background_colors[background_color_index];
               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;
         }
       }
     }
@@ -470,6 +722,11 @@ int main(int argc, char* argv[]) {
           ImGuiTexInspect::SizeExcludingBorder(wSize)
         );
 
+        CurrentInspector_SetAlphaMode(
+          ImGuiTexInspect::InspectorAlphaMode_CustomColor
+        );
+        ImGuiTexInspect::CurrentInspector_SetCustomBackgroundColor(clear_color);
+
         if (GRID_ENABLED) {
             CurrentInspector_ClearFlags(ImGuiTexInspect::InspectorFlags_NoGrid);
         }else {
@@ -520,6 +777,7 @@ int main(int argc, char* argv[]) {
       if (ImGui::BeginPopup("HelpPopup")) {
         ImGui::Text("tview Help");
         ImGui::Separator();
+        ImGui::Text("b - cycle background color");
         ImGui::Text("r - rotate 90 deg clockwise");
         ImGui::Text("g - toggle grid");
         ImGui::Text("a - toggle filtering");
@@ -527,14 +785,14 @@ int main(int argc, char* argv[]) {
         ImGui::Text("d - cycle pixel detail mode");
         ImGui::Separator();
         ImGui::Text("modes:");
-        ImGui::Text("\tOff");
+        ImGui::Text("	Off");
-        ImGui::Text("\tGradient Arrow");
+        ImGui::Text("	Gradient Arrow");
-        ImGui::Text("\tHex Code");
+        ImGui::Text("	Hex Code");
-        ImGui::Text("\tRGB Values");
+        ImGui::Text("	RGB Values");
-        ImGui::Text("\tFloat Values");
+        ImGui::Text("	Float Values");
         ImGui::Separator();
-        ImGui::Text("h - show help popup");
+        ImGui::Text("? - show help popup");
-        ImGui::Text("c - toggle color histogram");
+        ImGui::Text("h - toggle color histogram");
         ImGui::Text("e - toggle EXIF info");
         ImGui::Separator();
         ImGui::Text("q - quit");
@@ -542,131 +800,166 @@ int main(int argc, char* argv[]) {
         ImGui::Text("click anywhere to continue");
         ImGui::EndPopup();
       }
-      if (SHOW_EXIF && t.exif.CameraMake != "NULL") {
+      if (SHOW_EXIF) {
-        ImGuiWindowClass topmost;
+        if (t.exif.CameraMake != "NULL") {
-        topmost.ClassId = ImHashStr("TopMost");
+          ImGuiWindowClass topmost;
-        topmost.ViewportFlagsOverrideSet = ImGuiViewportFlags_TopMost;
+          topmost.ClassId = ImHashStr("TopMost");
-        ImGui::SetNextWindowClass(&topmost);
+          topmost.ViewportFlagsOverrideSet = ImGuiViewportFlags_TopMost;
-        ImGui::Begin("EXIF", NULL, ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoResize | ImGuiWindowFlags_AlwaysAutoResize  | ImGuiWindowFlags_NoFocusOnAppearing);
+          ImGui::SetNextWindowClass(&topmost);
-        if(ImGui::BeginTable("Hardware", 2)) {
+          ImGui::SetNextWindowSize(ImVec2(600, 600), ImGuiCond_FirstUseEver);
-          ImGui::TableNextRow();
+          ImGui::Begin("EXIF", &SHOW_EXIF, ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoFocusOnAppearing);
-          ImGui::TableSetColumnIndex(0);
+          if(ImGui::BeginTable("Hardware", 2, ImGuiTableFlags_Resizable)) {
-          ImGui::Text("Make");
+            ImGui::TableSetupColumn("Field", ImGuiTableColumnFlags_WidthFixed, ImGuiTableColumnFlags_NoHide, 150.0f);
-          ImGui::TableSetColumnIndex(1);
+            ImGui::TableSetupColumn("Value", ImGuiTableColumnFlags_WidthStretch);
-          ImGui::Text("%s", t.exif.CameraMake.c_str());
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Make");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.CameraMake.c_str());
 
-          ImGui::TableNextRow();
+            ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
+            ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Model");
+            ImGui::TextWrapped("Model");
-          ImGui::TableSetColumnIndex(1);
+            ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.CameraModel.c_str());
+            ImGui::TextWrapped("%s", t.exif.CameraModel.c_str());
 
-          ImGui::TableNextRow();
+            ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
+            ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Lens");
+            ImGui::TextWrapped("Lens");
-          ImGui::TableSetColumnIndex(1);
+            ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.LensModel.c_str());
+            ImGui::TextWrapped("%s", t.exif.LensModel.c_str());
 
-          ImGui::EndTable();
+            ImGui::EndTable();
+          }
+
+          ImGui::Separator();
+
+          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::TextWrapped("Shutter Speed");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.ShutterSpeed.c_str());
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("F-Stop");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.FNumber.c_str());
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("ISO");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.ISO.c_str());
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Focal Length");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.FocalLength.c_str());
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Exposure Comp");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.ExposureBias.c_str());
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Metering Mode");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.MeteringMode.c_str());
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Flash");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.Flash.c_str());
+
+            ImGui::EndTable();
+          }
+
+          ImGui::Separator();
+
+          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::TextWrapped("Date");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s %s", t.exif.TimeTaken.c_str(), t.exif.TimeTakenOffset.c_str());
+
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Dimensions");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%sx%s", t.exif.ImageDimensionX.c_str(), t.exif.ImageDimensiony.c_str());
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Orientation");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s", t.exif.ImageOrientation.c_str());
+
+            ImGui::EndTable();
+          }
+
+          ImGui::Separator();
+
+          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::TextWrapped("Latitude");
+            ImGui::TableSetColumnIndex(1);
+            ImGui::TextWrapped("%s %s", t.exif.GPSLat.c_str(), t.exif.GPSLatref.c_str());
+
+
+            ImGui::TableNextRow();
+            ImGui::TableSetColumnIndex(0);
+            ImGui::TextWrapped("Longitude");
+            ImGui::TableSetColumnIndex(1);
+            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");
+
+          ImGui::End();
+        } else {
+          ImGuiWindowClass topmost;
+          topmost.ClassId = ImHashStr("TopMost");
+          topmost.ViewportFlagsOverrideSet = ImGuiViewportFlags_TopMost;
+          ImGui::SetNextWindowClass(&topmost);
+          ImGui::SetNextWindowSize(ImVec2(200, 50), ImGuiCond_FirstUseEver);
+          ImGui::Begin("EXIF", &SHOW_EXIF, ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoFocusOnAppearing | ImGuiWindowFlags_AlwaysAutoResize);
+          ImGui::Text("No EXIF data available.");
+          ImGui::End();
         }
-
+    }
-        ImGui::Separator();
-
-        if(ImGui::BeginTable("Photo", 2)) {
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Shutter Speed");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ShutterSpeed.c_str());
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("F-Stop");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.FNumber.c_str());
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("ISO");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ISO.c_str());
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Focal Length");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.FocalLength.c_str());
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Exposure Comp");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ExposureBias.c_str());
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Metering Mode");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.MeteringMode.c_str());
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Flash");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.Flash.c_str());
-
-          ImGui::EndTable();
-        }
-
-        ImGui::Separator();
-
-        if(ImGui::BeginTable("Meta", 2)) {
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Date");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s %s", t.exif.TimeTaken.c_str(), t.exif.TimeTakenOffset.c_str());
-
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Dimensions");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%sx%s", t.exif.ImageDimensionX.c_str(), t.exif.ImageDimensiony.c_str());
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Orientation");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s", t.exif.ImageOrientation.c_str());
-
-          ImGui::EndTable();
-        }
-
-        ImGui::Separator();
-
-        if(ImGui::BeginTable("Location", 2)) {
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Latitude");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s %s", t.exif.GPSLat.c_str(), t.exif.GPSLatref.c_str());
-
-
-          ImGui::TableNextRow();
-          ImGui::TableSetColumnIndex(0);
-          ImGui::Text("Longitude");
-          ImGui::TableSetColumnIndex(1);
-          ImGui::Text("%s %s", t.exif.GPSLon.c_str(), t.exif.GPSLonref.c_str());
-
-          ImGui::EndTable();
-        }
-
-        ImGui::Separator();
-        ImGui::Text("Press e to hide");
-
-        ImGui::End();
-      }
 
 
       if (SHOW_HISTOGRAM) {
@@ -675,9 +968,13 @@ 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();
       }
@@ -687,8 +984,7 @@ int main(int argc, char* argv[]) {
     // Rendering
     ImGui::Render();
     glViewport(0, 0, (int)io.DisplaySize.x, (int)io.DisplaySize.y);
-    glClearColor(clear_color.x * clear_color.w, clear_color.y * clear_color.w,
+    glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
-                 clear_color.z * clear_color.w, clear_color.w);
     glClear(GL_COLOR_BUFFER_BIT);
     ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
     SDL_GL_SwapWindow(window);