Source code for silx.opencl.sift.match

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
#
#    Project: Sift implementation in Python + OpenCL
#             https://github.com/silx-kit/silx
#
#    Copyright (C) 2013-2018  European Synchrotron Radiation Facility, Grenoble, France
#
# 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.

"""
Contains a class for creating a matching plan, allocating arrays, 
compiling kernels and other things like that
"""

from __future__ import division, print_function, with_statement

__authors__ = ["Jérôme Kieffer", "Pierre Paleo"]
__contact__ = "jerome.kieffer@esrf.eu"
__license__ = "MIT"
__copyright__ = "European Synchrotron Radiation Facility, Grenoble, France"
__date__ = "17/01/2018"
__status__ = "production"


import logging
import numpy
from .param import par
from ..common import pyopencl, kernel_workgroup_size
from .utils import calc_size
from ..processing import OpenclProcessing, BufferDescription
logger = logging.getLogger(__name__)
if not pyopencl:
    logger.warning("No PyOpenCL, no sift")


[docs]class MatchPlan(OpenclProcessing): """Plan to compare sets of SIFT keypoint and find common ones. .. code-block:: python siftp = sift.MatchPlan(devicetype="ALL") commonkp = siftp.match(kp1,kp2) where kp1, kp2 is a n x 132 array. the second dimension is composed of x,y, scale and angle as well as 128 floats describing the keypoint. commonkp is mx2 array of matching keypoints """ kernels_size = {"matching_gpu": 64, "matching_cpu": 16} dtype_kp = numpy.dtype([('x', numpy.float32), ('y', numpy.float32), ('scale', numpy.float32), ('angle', numpy.float32), ('desc', (numpy.uint8, 128)) ]) def __init__(self, size=16384, devicetype="ALL", profile=False, device=None, block_size=None, roi=None, ctx=None): """Constructor of the class: :param size: size of the input keypoint-list alocated on the GPU. :param devicetype: can be CPU or GPU :param profile: set to true to activate profiling information collection :param device: 2-tuple of integer, see clinfo :param block_size: CPU on MacOS, limit to 1. None by default to use default ones (max=128). :param roi: Region Of Interest: TODO :param context: Use an external context (discard devicetype and device options) """ OpenclProcessing.__init__(self, ctx=ctx, devicetype=devicetype, block_size=block_size, profile=profile) self.kpsize = size self.octave_max = None self.red_size = None self.debug = [] devicetype = self.device.type if (devicetype == "CPU"): self.USE_CPU = True matching_kernel = "matching_cpu" else: self.USE_CPU = False matching_kernel = "matching_gpu" wg_size = self.__class__.kernels_size[matching_kernel] self.compile_kernels(kernel_files=["sift/sift", "sift/memset", "sift/" + matching_kernel], compile_options='-D WORKGROUP_SIZE=%s' % wg_size) self.roi = None if roi: self.set_roi(roi) buffers = [ # BufferDescription"name", "size", "dtype", "flags" BufferDescription("Kp_1", self.kpsize, self.dtype_kp, flags=None), BufferDescription("Kp_2", self.kpsize, dtype=self.dtype_kp, flags=None), BufferDescription("match", (self.kpsize, 2), dtype=numpy.int32, flags=None), BufferDescription("cnt", 1, numpy.int32, flags=None)] self.allocate_buffers(buffers, use_array=True) self.kernel_size = {} for name, kernel in self.kernels.get_kernels().items(): self.kernel_size[name] = kernel_workgroup_size(self.program, kernel)
[docs] def match(self, nkp1, nkp2, raw_results=False): """Calculate the matching of 2 keypoint list :param nkp1: numpy 1D recarray of keypoints or equivalent GPU buffer :param nkp2: numpy 1D recarray of keypoints or equivalent GPU buffer :param raw_results: if true return the 2D array of indexes of matching keypoints (not the actual keypoints) TODO: implement the ROI ... """ assert len(nkp1.shape) == 1 # Nota: nkp1.ndim is not valid for gpu_arrays assert len(nkp2.shape) == 1 valid_types = (numpy.ndarray, numpy.core.records.recarray, pyopencl.array.Array) assert isinstance(nkp1, valid_types) assert isinstance(nkp2, valid_types) result = None with self.sem: if isinstance(nkp1, pyopencl.array.Array): kpt1_gpu = nkp1 else: if nkp1.size > self.cl_mem["Kp_1"].size: logger.warning("increasing size of keypoint vector 1 to %i" % nkp1.size) self.cl_mem["Kp_1"] = pyopencl.array.empty(self.queue, (nkp1.size,), dtype=self.dtype_kp) kpt1_gpu = self.cl_mem["Kp_1"] self._reset_buffer1() evt1 = pyopencl.enqueue_copy(self.queue, kpt1_gpu.data, nkp1) if self.profile: self.events.append(("copy H->D KP_1", evt1)) if isinstance(nkp2, pyopencl.array.Array): kpt2_gpu = nkp2 else: if nkp2.size > self.cl_mem["Kp_2"].size: logger.warning("increasing size of keypoint vector 2 to %i" % nkp2.size) self.cl_mem["Kp_2"] = pyopencl.array.empty(self.queue, (nkp2.size,), dtype=self.dtype_kp) kpt2_gpu = self.cl_mem["Kp_2"] self._reset_buffer2() evt2 = pyopencl.enqueue_copy(self.queue, kpt2_gpu.data, nkp2) if self.profile: self.events.append(("copy H->D KP_2", evt2)) if min(kpt1_gpu.size, kpt2_gpu.size) > self.cl_mem["match"].shape[0]: self.kpsize = min(kpt1_gpu.size, kpt2_gpu.size) self.cl_mem["match"] = pyopencl.array.empty(self.queue, (self.kpsize, 2), dtype=numpy.int32) self._reset_output() wg = self.kernel_size["matching"] size = calc_size((nkp1.size,), (wg,)) evt = self.kernels.matching(self.queue, size, (wg,), kpt1_gpu.data, kpt2_gpu.data, self.cl_mem["match"].data, self.cl_mem["cnt"].data, numpy.int32(self.kpsize), numpy.float32(par.MatchRatio * par.MatchRatio), numpy.int32(nkp1.size), numpy.int32(nkp2.size)) if self.profile: self.events.append(("matching", evt)) size = self.cl_mem["cnt"].get()[0] match = numpy.empty(shape=(size, 2), dtype=numpy.int32) if size > 0: cpyD2H = pyopencl.enqueue_copy(self.queue, match, self.cl_mem["match"].data) if self.profile: self.events.append(("copy D->H match", cpyD2H)) if raw_results: result = match else: result = numpy.recarray(shape=(size, 2), dtype=self.dtype_kp) result[:, 0] = nkp1[match[:size, 0]] result[:, 1] = nkp2[match[:size, 1]] return result
__call__ = match def _reset_buffer(self): """Reseet all buffers""" self._reset_buffer1() self._reset_buffer2() self._reset_output() def _reset_buffer1(self): wg = self.kernel_size["memset_kp"] size = calc_size((self.cl_mem["Kp_1"].size,), (wg,)) ev1 = self.kernels.memset_kp(self.queue, size, (wg,), self.cl_mem["Kp_1"].data, numpy.float32(-1.0), numpy.uint8(0), numpy.int32(self.cl_mem["Kp_1"].size)) if self.profile: self.events.append(("memset Kp1", ev1)) def _reset_buffer2(self): wg = self.kernel_size["memset_kp"] size = calc_size((self.cl_mem["Kp_2"].size,), (wg,)) ev2 = self.kernels.memset_kp(self.queue, size, (wg,), self.cl_mem["Kp_2"].data, numpy.float32(-1.0), numpy.uint8(0), numpy.int32(self.cl_mem["Kp_2"].size)) if self.profile: self.events.append(("memset Kp2", ev2)) def _reset_output(self): ev3 = self.kernels.memset_int(self.queue, calc_size((self.cl_mem["match"].size,), (self.kernel_size["memset_int"],)), (self.kernel_size["memset_int"],), self.cl_mem["match"].data, numpy.int32(-1), numpy.int32(self.cl_mem["match"].size)) ev4 = self.kernels.memset_int(self.queue, (1,), (1,), self.cl_mem["cnt"].data, numpy.int32(0), numpy.int32(1)) if self.profile: self.events += [("memset match", ev3), ("memset cnt", ev4), ] reset_timer = OpenclProcessing.reset_log
[docs] def set_roi(self, roi): """Defines the region of interest :param roi: region of interest as 2D numpy array with non zero where valid pixels are """ with self.sem: self.roi = numpy.ascontiguousarray(roi, numpy.int8) self.cl_mem["ROI"] = pyopencl.array.to_device(self.queue, self.roi)
[docs] def unset_roi(self): """Unset the region of interest """ with self.sem: self.roi = None self.cl_mem["ROI"] = None
[docs]def match_py(nkp1, nkp2, raw_results=False): """Pure numpy implementation of match: :param nkp1, nkp2: Numpy record array of keypoints with descriptors :param raw_results: return the indices of valid indexes instead of :return: (2,n) 2D array of matching keypoints. """ assert len(nkp1.shape) == 1 assert len(nkp2.shape) == 1 valid_types = (numpy.ndarray, numpy.core.records.recarray) assert isinstance(nkp1, valid_types) assert isinstance(nkp2, valid_types) result = None desc1 = nkp1.desc desc2 = nkp2.desc big1 = desc1.astype(int)[:, numpy.newaxis, :] big2 = desc2.astype(int)[numpy.newaxis, :, :] big = abs(big1 - big2).sum(axis=-1) maxi = big.max(axis=-1) mini = big.min(axis=-1) amin = big.argmin(axis=-1) patched = big.copy() patched[numpy.arange(big.shape[0]), amin] = maxi mini2 = patched.min(axis=-1) ratio = mini.astype(float) / mini2 ratio[mini2 == 0] = 1.0 match_mask = ratio < (par.MatchRatio * par.MatchRatio) size = match_mask.sum() match = numpy.empty((size, 2), dtype=int) match[:, 0] = numpy.arange(nkp1.size)[match_mask] match[:, 1] = amin[match_mask] if raw_results: result = match else: result = numpy.recarray(shape=(size, 2), dtype=MatchPlan.dtype_kp) result[:, 0] = nkp1[match[:, 0]] result[:, 1] = nkp2[match[:, 1]] return result
def demo(): import scipy.misc from .plan import SiftPlan if hasattr(scipy.misc, "ascent"): img1 = scipy.misc.ascent() else: img1 = scipy.misc.lena() splan = SiftPlan(template=img1) kp1 = splan(img1) img2 = numpy.zeros_like(img1) img2[5:, 8:] = img1[:-5, :-8] kp2 = splan(img2) mp = MatchPlan() match = mp(kp1, kp2) print(match.shape) print(numpy.median(match[:, 0].x - match[:, 1].x)) print(numpy.median(match[:, 0].y - match[:, 1].y)) if __name__ == "__main__": demo()