The last step for their iOS install process is to run build_ios.sh, but that’s about where they leave you off with the instruction. So from here, let’s take a look at the build artifacts. The core library for Caffe2 on iOS is located inside the caffe2 folder:<\/p>\n
- \n
- caffe2\/libCaffe2_CPU.a<\/li>\n<\/ul>\n
And in the root folder:<\/p>\n
- \n
- libCAFFE2_NNPACK.a<\/li>\n
- libCAFFE2_PTHREADPOOL.a<\/li>\n<\/ul>\n
Create an Xcode project<\/h3>\n
Now that the library was built, I created a new iOS app project in Xcode with a single-view template. From here I drag and drop the
libCaffe2_CPU.a<\/code> file in to my project heirarchy along with the other two libs,libCAFFE2_NNPACK.a<\/code> andlibCAFFE2_PTHREADPOOL.a<\/code>. Select ‘Copy’ when prompted. The file is located atcaffe2\/build_ios\/caffe2\/libCaffe2_CPU.a<\/code>. This pulls a copy of the library in to my project and tells Xcode I want to link against the library. We need to do the same thing with protobuf, which is located incaffe2\/build_ios\/third_party\/protobuf\/cmake\/libprotobuf.a<\/code>.<\/p>\nIn my case I wanted to also include OpenCV2, which has it’s own requirements for setting up. You can learn about how to install OpenCV2 on their site<\/a>. The main problem I ran in to with OpenCV2 was figuring out that I needed to create a
Prefix.h<\/code> file, and then in the settings of the project set the Prefix Header file to beMyAppsName\/Prefix.h<\/code>. In my example project I called the projectDayMaker<\/code>, so for me it wasDayMaker\/Prefix.h<\/code>. Then I could put the following in the Prefix.h file so that OpenCV2 would get included before any Apple headers:<\/p>\n<\/code><\/pre>\n\n\n\n
\n \n \n#ifdef __cplusplus<\/code><\/div>\n\u00a0\u00a0\u00a0\u00a0<\/code>#<\/code>import<\/code><opencv2\/opencv.hpp><\/code><\/div>\n\u00a0\u00a0\u00a0\u00a0<\/code>#<\/code>import<\/code><opencv2\/stitching\/detail\/blenders.hpp><\/code><\/div>\n\u00a0\u00a0\u00a0\u00a0<\/code>#<\/code>import<\/code><opencv2\/stitching\/detail\/exposure_compensate.hpp><\/code><\/div>\n#endif<\/code><\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/code><\/pre>\n<\/p>\n
<\/code><\/pre>\n![\"Prefix](\"http:\/\/jamesonquave.com\/blog\/wp-content\/uploads\/prefix.png\")
<\/p>\nInclude the Caffe2 headers<\/h3>\n
In order to actually use the library, we’ll need to pull in the right headers. Assuming you have a directory structure where your caffe2 files are a level above your project. (I cloned caffe2 in to
~\/Code\/caffe2<\/code> and set up my project in~\/Code\/DayMaker<\/code>.) You’ll need to add the following User Header Search Path in your project settings:<\/p>\n<\/code><\/pre>\n\n\n\n
\n \n \n$(<\/code>SRCROOT<\/code>)\/..\/caffe2<\/code><\/div>\n$(<\/code>SRCROOT<\/code>)\/..\/caffe2\/build_ios<\/code><\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/code><\/pre>\n<\/p>\n
<\/code><\/pre>\nYou’ll also need to add the following to “Header Search Paths”<\/p>\n
<\/code><\/pre>\n\n\n\n
\n \n \n$(<\/code>SRCROOT<\/code>)\/..\/caffe2\/build_host_protoc\/include<\/code><\/div>\n$(<\/code>SRCROOT<\/code>)\/..\/caffe2\/third_party\/eigen<\/code><\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/code><\/pre>\n<\/p>\n
<\/code><\/pre>\nNow you can also try importing some caffe2 C++ headers in order to confirm it’s all working as expected. I created a new Objective-C class to wrap the Caffe2 C++ API around. To follow along, create a new Objective-C class called Caffe2. Then rename the
Caffe2.m<\/code> file it creates toCaffe2.mm<\/code>. This causes the compiler to see this as Objective-C++ instead of just Objective-C, a requirement for making this all work.<\/p>\nNext, I added some Caffe2 headers to the
.mm<\/code> file. At this point this is my entireCaffe2.mm<\/code> file:<\/p>\n<\/code><\/pre>\n\n\n\n
\n \n \n#<\/code>import<\/code>\"caffe2\/core\/context.h\"<\/code><\/div>\n#<\/code>import<\/code>\"caffe2\/core\/operator.h\"<\/code><\/div>\n#<\/code>import<\/code>\"Caffe2.h\"<\/code><\/div>\n<\/div>\n@implementation<\/code>Caffe2<\/code><\/div>\n<\/div>\n@end<\/code><\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/code><\/pre>\n<\/p>\n
<\/code><\/pre>\n