Adding JPEG reading support

CMakeLists.txt

@@ -67,6 +67,7 @@ set(BASISU_SRC_LIST ${COMMON_SRC_LIST}
 	basisu_bc7enc.cpp
 	lodepng.cpp
 	apg_bmp.c
+	jpgd.cpp
 	transcoder/basisu_transcoder.cpp
 	)
 

basisu.vcxproj

@@ -154,6 +154,7 @@
     <ClCompile Include="basisu_bc7enc.cpp" />
     <ClCompile Include="basisu_ssim.cpp" />
     <ClCompile Include="basisu_uastc_enc.cpp" />
+    <ClCompile Include="jpgd.cpp" />
     <ClCompile Include="transcoder\basisu_transcoder.cpp" />
     <ClInclude Include="apg_bmp.h" />
     <ClInclude Include="basisu_bc7enc.h" />
@@ -173,6 +174,7 @@
     <ClCompile Include="basisu_resample_filters.cpp" />
     <ClInclude Include="basisu_ssim.h" />
     <ClInclude Include="basisu_uastc_enc.h" />
+    <ClInclude Include="jpgd.h" />
     <ClInclude Include="lodepng.h" />
     <ClInclude Include="transcoder\basisu.h" />
     <ClInclude Include="transcoder\basisu_transcoder.h" />

basisu.vcxproj.filters

@@ -22,6 +22,7 @@
     <ClCompile Include="basisu_uastc_enc.cpp" />
     <ClCompile Include="basisu_bc7enc.cpp" />
     <ClCompile Include="apg_bmp.c" />
+    <ClCompile Include="jpgd.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="basisu_basis_file.h" />
@@ -58,6 +59,7 @@
       <Filter>transcoder</Filter>
     </ClInclude>
     <ClInclude Include="apg_bmp.h" />
+    <ClInclude Include="jpgd.h" />
   </ItemGroup>
   <ItemGroup>
     <None Include="transcoder\basisu_transcoder_tables_dxt1_6.inc">

basisu_enc.cpp

@@ -20,6 +20,7 @@
 #include "transcoder/basisu_transcoder.h"
 #include "basisu_bc7enc.h"
 #include "apg_bmp.h"
+#include "jpgd.h"
 
 #if defined(_WIN32)
 // For QueryPerformanceCounter/QueryPerformanceFrequency
@@ -229,7 +230,7 @@ namespace basisu
 
 		return true;
 	}
-
+		
 	bool load_tga(const char* pFilename, image& img)
 	{
 		int w = 0, h = 0, n_chans = 0;
@@ -326,6 +327,20 @@ namespace basisu
 		return true;
 	}
 
+	bool load_jpg(const char *pFilename, image& img)
+	{
+		int width = 0, height = 0, actual_comps = 0;
+		uint8_t *pImage_data = jpgd::decompress_jpeg_image_from_file(pFilename, &width, &height, &actual_comps, 4, 0);
+		if (!pImage_data)
+			return false;
+		
+		img.init(pImage_data, width, height, 4);
+		
+		free(pImage_data);
+
+		return true;
+	}
+
 	bool load_image(const char* pFilename, image& img)
 	{
 		std::string ext(string_get_extension(std::string(pFilename)));
@@ -341,6 +356,8 @@ namespace basisu
 			return load_bmp(pFilename, img);
 		if (strcasecmp(pExt, "tga") == 0)
 			return load_tga(pFilename, img);
+		if ( (strcasecmp(pExt, "jpg") == 0) || (strcasecmp(pExt, "jfif") == 0) || (strcasecmp(pExt, "jpeg") == 0) )
+			return load_jpg(pFilename, img);
 
 		return false;
 	}
@@ -1933,5 +1950,5 @@ namespace basisu
 		
 		return read_tga(&filedata[0], (uint32_t)filedata.size(), width, height, n_chans);
 	}
-
+		
 } // namespace basisu

basisu_enc.h

@@ -132,6 +132,16 @@ namespace basisu
 		return v;
 	}
 
+	inline uint32_t wang_hash(uint32_t seed)
+	{
+		 seed = (seed ^ 61) ^ (seed >> 16);
+		 seed *= 9;
+		 seed = seed ^ (seed >> 4);
+		 seed *= 0x27d4eb2d;
+		 seed = seed ^ (seed >> 15);
+		 return seed;
+	}
+
 	uint32_t hash_hsieh(const uint8_t* pBuf, size_t len);
 
 	template <typename Key>
@@ -2270,6 +2280,12 @@ namespace basisu
 			resize(w, h, p);
 		}
 
+		image(const uint8_t *pImage, uint32_t width, uint32_t height, uint32_t comps) :
+			m_width(0), m_height(0), m_pitch(0)
+		{
+			init(pImage, width, height, comps);
+		}
+
 		image(const image &other) :
 			m_width(0), m_height(0), m_pitch(0)
 		{
@@ -2318,6 +2334,47 @@ namespace basisu
 			return *this;
 		}
 
+		void init(const uint8_t *pImage, uint32_t width, uint32_t height, uint32_t comps)
+		{
+			assert(comps >= 1 && comps <= 4);
+			
+			resize(width, height);
+
+			for (uint32_t y = 0; y < height; y++)
+			{
+				for (uint32_t x = 0; x < width; x++)
+				{
+					const uint8_t *pSrc = &pImage[(x + y * width) * comps];
+					color_rgba &dst = (*this)(x, y);
+
+					if (comps == 1)
+					{
+						dst.r = pSrc[0];
+						dst.g = pSrc[0];
+						dst.b = pSrc[0];
+						dst.a = 255;
+					}
+					else if (comps == 2)
+					{
+						dst.r = pSrc[0];
+						dst.g = pSrc[0];
+						dst.b = pSrc[0];
+						dst.a = pSrc[1];
+					}
+					else
+					{
+						dst.r = pSrc[0];
+						dst.g = pSrc[1];
+						dst.b = pSrc[2];
+						if (comps == 4)
+							dst.a = pSrc[3];
+						else
+							dst.a = 255;
+					}
+				}
+			}
+		}
+
 		image &fill_box(uint32_t x, uint32_t y, uint32_t w, uint32_t h, const color_rgba &c)
 		{
 			for (uint32_t iy = 0; iy < h; iy++)
@@ -2807,6 +2864,9 @@ namespace basisu
 		
 	bool load_tga(const char* pFilename, image& img);
 	inline bool load_tga(const std::string &filename, image &img) { return load_tga(filename.c_str(), img); }
+
+	bool load_jpg(const char *pFilename, image& img);
+	inline bool load_jpg(const std::string &filename, image &img) { return load_jpg(filename.c_str(), img); }
 	
 	// Currently loads .BMP, .PNG, or .TGA.
 	bool load_image(const char* pFilename, image& img);
@@ -2814,7 +2874,7 @@ namespace basisu
 
 	uint8_t *read_tga(const uint8_t *pBuf, uint32_t buf_size, int &width, int &height, int &n_chans);
 	uint8_t *read_tga(const char *pFilename, int &width, int &height, int &n_chans);
-
+		
 	enum
 	{
 		cImageSaveGrayscale = 1,

basisu_tool.cpp

@@ -52,11 +52,11 @@ static void print_usage()
 	printf("\nUsage: basisu filename [filename ...] <options>\n");
 	
 	puts("\n"
-		"The default mode is compression of one or more PNG/BMP/TGA files to a .basis file. Alternate modes:\n"
+		"The default mode is compression of one or more PNG/BMP/TGA/JPG files to a .basis file. Alternate modes:\n"
 		" -unpack: Use transcoder to unpack .basis file to one or more .ktx/.png files\n"
 		" -validate: Validate and display information about a .basis file\n"
 		" -info: Display high-level information about a .basis file\n"
-		" -compare: Compare two PNG/BMP/TGA images specified with -file, output PSNR and SSIM statistics and RGB/A delta images\n"
+		" -compare: Compare two PNG/BMP/TGA/JPG images specified with -file, output PSNR and SSIM statistics and RGB/A delta images\n"
 		" -version: Print basisu version and exit\n"
 		"Unless an explicit mode is specified, if one or more files have the .basis extension this tool defaults to unpack mode.\n"
 		"\n"
@@ -66,8 +66,8 @@ static void print_usage()
 		"Filenames prefixed with a @ symbol are read as filename listing files. Listing text files specify which actual filenames to process (one filename per line).\n"
 		"\n"
 		"Options:\n"
-		" -file filename.png/bmp/tga: Input image filename, multiple images are OK, use -file X for each input filename (prefixing input filenames with -file is optional)\n"
-		" -alpha_file filename.png/bmp/tga: Input alpha image filename, multiple images are OK, use -file X for each input filename (must be paired with -file), images converted to REC709 grayscale and used as input alpha\n"
+		" -file filename.png/bmp/tga/jpg: Input image filename, multiple images are OK, use -file X for each input filename (prefixing input filenames with -file is optional)\n"
+		" -alpha_file filename.png/bmp/tga/jpg: Input alpha image filename, multiple images are OK, use -file X for each input filename (must be paired with -file), images converted to REC709 grayscale and used as input alpha\n"
 		" -multifile_printf: printf() format strint to use to compose multiple filenames\n"
 		" -multifile_first: The index of the first file to process, default is 0 (must specify -multifile_printf and -multifile_num)\n"
 		" -multifile_num: The total number of files to process.\n"