jpg_loader: introduced jpg decode using libjpeg-turbo

This patch introduces a jpg loader.
For decoding the image, libjpeg-turbo library is used. Library was found to be
fast (SIMD instructions accelerated) and portable.

@issue: #517

meson.build

@@ -28,6 +28,10 @@ if get_option('loaders').contains('png') == true
     config_h.set10('THORVG_PNG_LOADER_SUPPORT', true)
 endif
 
+if get_option('loaders').contains('jpg') == true
+    config_h.set10('THORVG_JPG_LOADER_SUPPORT', true)
+endif
+
 if get_option('vectors').contains('avx') == true
     config_h.set10('THORVG_AVX_VECTOR_SUPPORT', true)
 endif

meson_options.txt

@@ -6,7 +6,7 @@ option('engines',
 
 option('loaders',
    type: 'array',
-   choices: ['', 'svg', 'tvg', 'png'],
+   choices: ['', 'svg', 'tvg', 'png', 'jpg'],
    value: ['svg'],
    description: 'Enable File Loaders in thorvg')
 

src/lib/tvgLoaderMgr.cpp

@@ -33,6 +33,10 @@
     #include "tvgTvgLoader.h"
 #endif
 
+#ifdef THORVG_JPG_LOADER_SUPPORT
+    #include "tvgJpgLoader.h"
+#endif
+
 #include "tvgRawLoader.h"
 
 /************************************************************************/
@@ -61,6 +65,12 @@ static Loader* _find(FileType type)
         case FileType::Tvg: {
 #ifdef THORVG_TVG_LOADER_SUPPORT
             return new TvgLoader;
+#endif
+            break;
+        }
+        case FileType::Jpg: {
+#ifdef THORVG_JPG_LOADER_SUPPORT
+            return new JpgLoader;
 #endif
             break;
         }
@@ -88,6 +98,10 @@ static Loader* _find(FileType type)
             format = "TVG";
             break;
         }
+        case FileType::Jpg: {
+            format = "JPG";
+            break;
+        }
         default: {
             format = "???";
             break;
@@ -106,6 +120,7 @@ static Loader* _find(const string& path)
     if (!ext.compare("svg")) return _find(FileType::Svg);
     if (!ext.compare("png")) return _find(FileType::Png);
     if (!ext.compare("tvg")) return _find(FileType::Tvg);
+    if (!ext.compare("jpg")) return _find(FileType::Jpg);
     return nullptr;
 }
 

src/lib/tvgLoaderMgr.h

@@ -24,7 +24,7 @@
 
 #include "tvgLoader.h"
 
-enum class FileType { Tvg = 0, Svg, Raw, Png, Unknown };
+enum class FileType { Tvg = 0, Svg, Raw, Png, Jpg, Unknown };
 
 struct LoaderMgr
 {

src/loaders/jpg/meson.build

@@ -0,0 +1,18 @@
+source_file = [
+   'tvgJpgLoader.h',
+   'tvgJpgLoader.cpp',
+]
+
+jpg_dep = dependency('libturbojpeg', required: false)
+if not jpg_dep.found()
+	jpg_dep = cc.find_library('turbojpeg', required: false)
+endif
+if not jpg_dep.found()
+	error('JPEG image loading requires libturbojpeg or turbojpeg, neither was found.')
+endif
+
+subloader_dep += [declare_dependency(
+    include_directories : include_directories('.'),
+    dependencies : jpg_dep,
+    sources : source_file
+)]

src/loaders/jpg/tvgJpgLoader.cpp

@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2021 Samsung Electronics Co., Ltd. All rights reserved.
+
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "tvgLoaderMgr.h"
+#include "tvgJpgLoader.h"
+
+JpgLoader::JpgLoader()
+{
+    jpegDecompressor = tjInitDecompress();
+}
+
+JpgLoader::~JpgLoader()
+{
+    tjDestroy(jpegDecompressor);
+    tjFree(image);
+    image = NULL;
+}
+
+bool JpgLoader::open(const string& path)
+{
+    bool success = false;
+    FILE *jpegFile = NULL;
+    if ((jpegFile = fopen(path.c_str(), "rb")) == NULL) return false;
+
+    //determine size
+    if (fseek(jpegFile, 0, SEEK_END) < 0) goto finalize;
+    if (((size = ftell(jpegFile)) < 1)) goto finalize;
+    if (fseek(jpegFile, 0, SEEK_SET)) goto finalize;
+
+    if (data) tjFree(data);
+    data = (unsigned char *) tjAlloc(size);
+    if (!data) goto finalize;
+
+    if (fread(data, size, 1, jpegFile) < 1) goto failure;
+
+    success = true;
+    goto finalize;
+
+failure:
+    tjFree(data);
+    data = NULL;
+
+finalize:
+    fclose(jpegFile);
+    return success;
+}
+
+bool JpgLoader::read()
+{
+    int width, height;
+
+    //decompress header
+    int inSubsamp, inColorspace;
+    if (tjDecompressHeader3(jpegDecompressor, data, size, &width, &height, &inSubsamp, &inColorspace) < 0) return false;
+
+    //alloc image buffer
+    if (image) tjFree(image);
+    image = (unsigned char *)tjAlloc(width * height * tjPixelSize[TJPF_BGRX]);
+    if (!image) return false;
+
+    //decompress jpg image
+    if (tjDecompress2(jpegDecompressor, data, size, image, width, 0, height, TJPF_BGRX, 0) < 0) {
+        tjFree(image);
+        data = NULL;
+        return false;
+    }
+
+    vw = w = width;
+    vh = h = height;
+    return true;
+}
+
+bool JpgLoader::close()
+{
+    tjFree(data);
+    data = NULL;
+    return true;
+}
+
+const uint32_t* JpgLoader::pixels()
+{
+    return (const uint32_t*)image;
+}

src/loaders/jpg/tvgJpgLoader.h

@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2021 Samsung Electronics Co., Ltd. All rights reserved.
+
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#ifndef _TVG_JPG_LOADER_H_
+#define _TVG_JPG_LOADER_H_
+
+#include <turbojpeg.h>
+
+class JpgLoader : public Loader
+{
+public:
+    JpgLoader();
+    ~JpgLoader();
+
+    using Loader::open;
+    bool open(const string& path) override;
+    bool read() override;
+    bool close() override;
+
+    const uint32_t* pixels() override;
+
+private:
+    tjhandle jpegDecompressor;
+    unsigned char* data = nullptr;
+    unsigned long size = 0;
+    unsigned char *image = nullptr;
+};
+
+#endif //_TVG_JPG_LOADER_H_

src/loaders/meson.build

@@ -12,6 +12,11 @@ if get_option('loaders').contains('tvg') == true
     subdir('tvg')
 endif
 
+if get_option('loaders').contains('jpg') == true
+    subdir('jpg')
+    message('Enable JPG Loader')
+endif
+
 subdir('raw')
 
 loader_dep = declare_dependency(