Affine-SIFT(C++)

Demo code for Affine-SIFT (ASIFT) image matching ------------------------------------------------------------------------- ------------------------------------------------------------------------- Jean-Michel Morel (Jean-Michel Morel <morel@cmla.ens-cachan.fr>) Guoshen Yu (yu@cmap.polytechnique.fr) Version 2.2, April. 10, 2010 This directory contains the C++ code for ASIFT, a fully affine invariant image matching algorithm. ************************** Unix/Linux/Mac Users ************************** For Unix/Linux and Mac users, the code is ready to be compiled. The executable adapted to your computer system is generated after compiling. ************************************************************************** ***************************** Windows Users ****************************** For Windows users, the executable as well as the code is provided. (For the executable, you need to download separately the installation file from http://www.ipol.im/pub/algo/my_affine_sift/ .) ************************************************************************** **************************** Matlab Interface **************************** Although the ASIFT program is standalone and can be executed without Matlab, a Matlab interface is provided (for Unix/Linux/Mac/Windows users). ************************************************************************** Source code compilation and software usage across platforms is detailed in this manual. If you have any problem using the this program, please contact Guoshen Yu yu@cmap.polytechnique.fr For more information about ASIFT, please see the web page at http://www.ipol.im/pub/algo/my_affine_sift/. You can also try ASIFT using the online demo. The online demo allows testing ASIFT with your own images without installing the program. If you use the ASIFT code or software, please cite the following paper: J.M. Morel and G.Yu, ASIFT: A New Framework for Fully Affine Invariant Image Comparison, SIAM Journal on Imaging Sciences, vol. 2, issue 2, pp. 438-469, 2009. ------------------------------------------------------------------------- ------------------------------------------------------------------------- I. UNIX/LINUX/MAC USER GUIDE The source code needs to be compiled before the software can be used. The compilation requires the make program, and is typically straightforward. - Library. This code requires the libpng library. You can automatically download, compile and include this library to the compiled program by adding the LOCAL_LIBS=1 option to the make commands. - Image format. Only the PNG format is supported. ------------------------------------------------------------------------- Source compilation and software usage 1. Download the ASIFT code package and extract it. Go to that directory. 2. Compile the source code (on Unix/Linux/Mac OS). There are two ways to compile the code. (1) RECOMMENDED, with Open Multi-Processing multithread parallelization (http://openmp.org/). Roughly speaking, it accelerates the program using the multiple processors in the computer. Run make OMP=1 OR (2) If the complier does not support OpenMp, run make ATTENTION: If libpng (the official PNG reference library) is not installed in your computer, an option LOCAL_LIBS=1 should be added after make. Example make OMP=1 LOCAL_LIBS=1 The compilation will automatically download and compile libpng and zlib and include the library to the program. 3. Run ASIFT. ./demo_ASIFT imgIn1.png, imgIn2.png imgOutVert.png imgOutHori.png matchings.txt keys1.txt keys2.txt -- imgIn1.png, imgIn2.png: Input images (in png format). -- imgOutVert.png, imgOutHori.png: Output images (vertical/horizontal concatenated). The detected matches are connected by write lines. -- matchings.txt: The file format starts with 1 integer giving the total number of matches. Then each line specifies the coordinates (col1, row1, col2, row2) of a pair of matched points. (col: horizontal axis, from left to right. row: vertical axis, from top to bottom.) -- keys1.txt keys2.txt: ASIFT keypoints in the two images, in the same format as the SIFT keypoints of David Lowe. The file starts with 2 integers giving the total number of keypoints and the length of the descriptor vector for each keypoint (128). Then the location of each keypoint in the image is specified by 4 floating point numbers giving subpixel column and row location, scale, and orientation (in radians from -PI to PI). Finally, the invariant descriptor vector for the keypoint is given as a list of 128 integers in range [0,255]. -- [optional 0/1]. 1: input images resize to an area equal to 800x600 for ASIFT, in keeping the aspect ratio (by default). 0: no resize. The resize is to limit the ASIFT computation time. The results (output images, keypoint coordinates and scales) are normalized to the original image size, so the resize is "transparent" to the user. Example, run ./demo_ASIFT adam1.png adam2.png imgOutVert.png imgOutHori.png matchings.txt keys1.txt keys2.txt You get on the screen "WARNING: The input images are resized to 800x600 for ASIFT. But the results will be normalized to the original image size. Computing keypoints on the two images... 12928 ASIFT keypoints are detected. 8972 ASIFT keypoints are detected. Keypoints computation accomplished in 24 seconds. Matching the keypoints... The two images match! 914 matchings are identified. log(nfa)=-1496.88. Keypoints matching accomplished in 4 seconds." ------------------------------------------------------------------------- ------------------------------------------------------------------------- II. WINDOWS USER GUIDE _________________________________________________________________________ A. EXECUTABLE _________________________________________________________________________ For Windows users who do not want to recompile the source code, an ASIFT executable installation file can be download separately from http://www.ipol.im/pub/algo/my_affine_sift/. - The provided Windows executable demo_ASIFT.exe has been compiled by the Intel C++ compiler on 32-bit Windows. It is executable on both 32-bit and 64-bit Windows, although it is not optimized for the latter. - The executable has not been extensively tested. If you have any problem using it, please contact Guoshen Yu yu@cmap.polytechnique.fr. Usage: 1. Download the installation file demo_ASIFTsetp.exe from http://www.ipol.im/pub/algo/my_affine_sift/ 2. Install the program. Double click the file demo_ASIFTsetp.exe. A small library distributed by Microsoft (Microsoft Visual C++ 2010 Redistributable Package) will be installed to your PC. The ASIFT software will be installed to C:\Program Files\demo_ASIFT 3. Run ASIFT. Run a Dos command prompt (you find it in Start > All Programs > Accessories > Command Prompt) - Go to the ASIFT directory by typing cd C:\Program Files\demo_ASIFT. - Run the ASIFT program by typing demo_ASIFT adam1.png adam2.png imgOutVert.png imgOutHori.png matchings.txt keys1.txt keys2.txt (It follows the same syntax of that for Unix/Linux/Mac described above.) You can of course move the ASIFT directory C:\Program Files\demo_ASIFT to wherever that is more convenient. ------------------------------------------------------------------------- Troubleshooting 1. If you are able to run the program but the results are not written to the output files, check and make sure that you have the write file permission in the demo_ASIFT directory. 2. Microsoft Visual Studio is NOT required to run the program. However, in case you cannot run the program (for example some library or dll is missing), you may try installing a Microsoft Visual Studio and then running again the program. _________________________________________________________________________ B. SOURCE COMPILATION _________________________________________________________________________ Windows users who want to recompile the source code themselve