Robust image I/O (#6765)

- Use file signatures (beginning bytes) instead of filename extension (png/jpg) to select decoder. jpg files with png extension and vice versa are read correctly.
- Catch libjpeg errors and report as normal Open3D exceptions. Change Open3D warnings to errors (exceptions) on jpeg I/O error.
- Simplify demo_scene example
- Clear image on read error
- Fix for github release macOS bug.

.github/workflows/documentation.yml

@@ -92,7 +92,7 @@ jobs:
  tar_file="open3d-${GITHUB_SHA}-docs.tar.gz"
  rm -rf ${tar_file}
  # Docs in docs/_out/html
- tar -C docs/_out -czf ${tar_file} html
+ tar -C docs/_out -cvzf ${tar_file} html
 
  echo "Waiting for other release assets..."
  this_sha=$(echo ${GITHUB_SHA} | cut -c 1-6)
@@ -110,7 +110,6 @@ jobs:
  echo "\nAll assets ready. Removing release assets except from last 3 commits: ${last_shas[@]}"
  release_assets=($(gh release view main-devel --json assets --jq '.assets[] | .name'))
  last_shas=($(git log --pretty=format:%h --abbrev-commit -n 3))
- echo "Waiting for all assets to be ready..."
  for relass in "${release_assets[@]}"; do
  found=false
  for last_sha in "${last_shas[@]}"; do

.github/workflows/macos.yml

@@ -168,8 +168,6 @@ jobs:
  path: open3d-*-app-macosx-10_15-universal2.zip
  if-no-files-found: error
 
- - name: Checkout source code
- uses: actions/checkout@v4
  - name: Update viewer devel release
  if: ${{ github.ref == 'refs/heads/main' }}
  env:

cpp/open3d/io/ImageIO.cpp

@@ -7,24 +7,25 @@
 
 #include "open3d/io/ImageIO.h"
 
+#include <array>
+#include <fstream>
 #include <unordered_map>
 
 #include "open3d/utility/FileSystem.h"
 #include "open3d/utility/Logging.h"
 
 namespace open3d {
+namespace io {
 
 namespace {
-using namespace io;
 
-static const std::unordered_map<
- std::string,
- std::function<bool(const std::string &, geometry::Image &)>>
- file_extension_to_image_read_function{
- {"png", ReadImageFromPNG},
- {"jpg", ReadImageFromJPG},
- {"jpeg", ReadImageFromJPG},
- };
+using signature_decoder_t =
+ std::pair<std::string,
+ std::function<bool(const std::string &, geometry::Image &)>>;
+static const std::array<signature_decoder_t, 2> signature_decoder_list{
+ {{"\x89\x50\x4e\x47\xd\xa\x1a\xa", ReadImageFromPNG},
+ {"\xFF\xD8\xFF", ReadImageFromJPG}}};
+static constexpr uint8_t MAX_SIGNATURE_LEN = 8;
 
 static const std::unordered_map<
  std::string,
@@ -34,11 +35,8 @@ static const std::unordered_map<
  {"jpg", WriteImageToJPG},
  {"jpeg", WriteImageToJPG},
  };
-
 } // unnamed namespace
 
-namespace io {
-
 std::shared_ptr<geometry::Image> CreateImageFromFile(
  const std::string &filename) {
  auto image = std::make_shared<geometry::Image>();
@@ -47,21 +45,27 @@ std::shared_ptr<geometry::Image> CreateImageFromFile(
 }
 
 bool ReadImage(const std::string &filename, geometry::Image &image) {
- std::string filename_ext =
- utility::filesystem::GetFileExtensionInLowerCase(filename);
- if (filename_ext.empty()) {
- utility::LogWarning(
- "Read geometry::Image failed: missing file extension.");
- return false;
- }
- auto map_itr = file_extension_to_image_read_function.find(filename_ext);
- if (map_itr == file_extension_to_image_read_function.end()) {
- utility::LogWarning(
- "Read geometry::Image failed: file extension {} unknown",
- filename_ext);
- return false;
+ std::string signature_buffer(MAX_SIGNATURE_LEN, 0);
+ std::ifstream file(filename, std::ios::binary);
+ file.read(&signature_buffer[0], MAX_SIGNATURE_LEN);
+ std::string err_msg;
+ if (!file) {
+ err_msg = "Read geometry::Image failed for file {}. I/O error.";
+ } else {
+ file.close();
+ for (const auto &signature_decoder : signature_decoder_list) {
+ if (signature_buffer.compare(0, signature_decoder.first.size(),
+ signature_decoder.first) == 0) {
+ return signature_decoder.second(filename, image);
+ }
+ }
+ err_msg =
+ "Read geometry::Image failed for file {}. Unknown file "
+ "signature, only PNG and JPG are supported.";
  }
- return map_itr->second(filename, image);
+ image.Clear();
+ utility::LogWarning(err_msg.c_str(), filename);
+ return false;
 }
 
 bool WriteImage(const std::string &filename,

cpp/open3d/io/ImageIO.h

@@ -69,11 +69,18 @@ bool WriteImageToJPG(const std::string &filename,
  const geometry::Image &image,
  int quality = kOpen3DImageIODefaultQuality);
 
-/// The general entrance for reading an Image from memory
+/// Read a PNG image from memory.
+/// \param image_data_ptr the pointer to image data in memory.
+/// \param image_data_size the size of image data in memory.
+/// \return return true if the read function is successful, false otherwise.
 bool ReadPNGFromMemory(const unsigned char *image_data_ptr,
  size_t image_data_size,
  geometry::Image &image);
 
+/// Read a JPG image from memory.
+/// \param image_data_ptr the pointer to image data in memory.
+/// \param image_data_size the size of image data in memory.
+/// \return return true if the read function is successful, false otherwise.
 bool ReadJPGFromMemory(const unsigned char *image_data_ptr,
  size_t image_data_size,
  geometry::Image &image);