Source code for xmipp3.protocols.protocol_ransac

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# * Authors:     Javier Vargas and Adrian Quintana (
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# * Unidad de  Bioinformatica of Centro Nacional de Biotecnologia , CSIC
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import os
from math import floor

from pyworkflow.object import Float
from pyworkflow.utils.path import cleanPath, copyFile
from pyworkflow.protocol.params import (PointerParam, FloatParam, BooleanParam,
                                        IntParam, StringParam,
                                        STEPS_PARALLEL, LEVEL_ADVANCED, USE_GPU, GPU_LIST)

from pwem.emlib.image import ImageHandler
from pwem.protocols import ProtInitialVolume
from pwem.objects import SetOfClasses2D

from pwem import emlib
from xmipp3.convert import (writeSetOfClasses2D, readSetOfVolumes,
from xmipp3.base import isMdEmpty, isXmippCudaPresent

[docs]class XmippProtRansac(ProtInitialVolume): """ Computes an initial 3d model from a set of projections/classes using RANSAC algorithm. This method is based on an initial non-lineal dimensionality reduction approach which allows to select representative small sets of class average images capturing the most of the structural information of the particle under study. These reduced sets are then used to generate volumes from random orientation assignments. The best volume is determined from these guesses using a random sample consensus (RANSAC) approach. """ _label = 'ransac' def __init__(self, **args): ProtInitialVolume.__init__(self, **args) self.stepsExecutionMode = STEPS_PARALLEL #--------------------------- DEFINE param functions -------------------------------------------- def _defineParams(self, form): form.addHidden(USE_GPU, BooleanParam, default=True, label="Use GPU for execution", help="This protocol has both CPU and GPU implementation.\ Select the one you want to use.") form.addHidden(GPU_LIST, StringParam, default='0', expertLevel=LEVEL_ADVANCED, label="Choose GPU IDs", help="Add a list of GPU devices that can be used") form.addSection(label='Input') form.addParam('inputSet', PointerParam, label="Input averages", important=True, pointerClass='SetOfClasses2D, SetOfAverages',# pointerCondition='hasRepresentatives', help='Select the input images from the project.' 'It should be a SetOfClasses2D object') form.addParam('symmetryGroup', StringParam, default="c1", label='Symmetry group', help="See" " for a description of the symmetry groups format in Xmipp.\n" "If no symmetry is present, use _c1_.") form.addParam('angularSampling', FloatParam, default=5, expertLevel=LEVEL_ADVANCED, label='Angular sampling rate', help='In degrees.' ' This sampling defines how fine the projection gallery from the volume is explored.') form.addParam('nRansac', IntParam, default="400", expertLevel=LEVEL_ADVANCED, label="Number of RANSAC iterations", help='Number of initial volumes to test by RANSAC') form.addParam('dimRed', BooleanParam, default=False, expertLevel=LEVEL_ADVANCED, label='Perform dimensionality reduction', help='The dimensionality reduction is performed using the Local Tangent Space' 'Alignment. See') form.addParam('numGrids', IntParam, default=3, condition='dimRed', expertLevel=LEVEL_ADVANCED, label='Number of grids per dimension', help='Number of squares to sample the classes') form.addParam('numSamples', IntParam, default=8, condition='not dimRed', expertLevel=LEVEL_ADVANCED, label='Number of random samples', help='Number of squares to sample the classes') form.addParam('corrThresh', FloatParam, default=0.77, expertLevel=LEVEL_ADVANCED, label='Inliers threshold', help='Correlation value threshold to determine if an experimental projection is an inlier or outlier.') form.addParam('numVolumes', IntParam, default=10, expertLevel=LEVEL_ADVANCED, label='Number of best volumes to refine', help='Number of best volumes to refine using projection matching approach and the input classes') form.addParam('numIter', IntParam, default=10, expertLevel=LEVEL_ADVANCED, label='Number of iterations to refine the volumes', help='Number of iterations to refine the best volumes using projection matching approach and the input classes') form.addParam('initialVolume', PointerParam, label="Initial volume", expertLevel=LEVEL_ADVANCED, pointerClass='Volume', allowsNull=True, help='You may provide a very rough initial volume as a way to constraint the angular search.' 'For instance, when reconstructing a fiber, you may provide a cylinder so that side views' 'are assigned to the correct tilt angle, although the rotational angle may be completely wrong') form.addParam('maxFreq', IntParam, default=12, expertLevel=LEVEL_ADVANCED, label='Max frequency of the initial volume', help=' Max frequency of the initial volume in Angstroms') form.addParam('useAll', BooleanParam, default=False, expertLevel=LEVEL_ADVANCED, label='Use all images to refine', help=' When refining a RANSAC volume, use all images to refine it instead of only inliers') form.addParallelSection(threads=8, mpi=1) #--------------------------- INSERT steps functions -------------------------------------------- def _insertAllSteps(self): # Insert some initialization steps initialStepId = self._insertInitialSteps() deps = [] # Store all steps ids, final step createOutput depends on all of them for n in range(self.nRansac.get()): # CTF estimation with Xmipp stepId = self._insertFunctionStep('ransacIterationStep', n, prerequisites=[initialStepId]) # Make estimation steps indepent between them deps.append(stepId) # Look for threshold, evaluate volumes and get the best self._insertFunctionStep("getCorrThreshStep", prerequisites=deps) # Make estimation steps indepent between them) self._insertFunctionStep("evaluateVolumesStep") bestVolumesStepId = self._insertFunctionStep("getBestVolumesStep") deps = [] # Store all steps ids, final step createOutput depends on all of them # Refine the best volumes for n in range(self.numVolumes.get()): fnBase='proposedVolume%05d' % n fnRoot=self._getPath(fnBase) for it in range(self.numIter.get()): if it==0: self._insertFunctionStep('reconstructStep',fnRoot, prerequisites=[bestVolumesStepId]) else: self._insertFunctionStep('reconstructStep',fnRoot) self._insertFunctionStep('projMatchStep',fnBase) stepId = self._insertFunctionStep("resizeStep",fnRoot,self.Xdim) deps.append(stepId) # Score each of the final volumes self._insertFunctionStep("scoreFinalVolumes", prerequisites=deps) # Make estimation steps indepent between them self._insertFunctionStep('createOutputStep') def _insertInitialSteps(self): # Convert the input classes to a metadata ready for xmipp self.imgsFn = self._getExtraPath('input_classes.xmd') self._insertFunctionStep('convertInputStep', self.imgsFn) inputSet = self.inputSet.get() self.Xdim = inputSet.getDimensions()[0] fnOutputReducedClass = self._getExtraPath("reducedClasses.xmd") fnOutputReducedClassNoExt = os.path.splitext(fnOutputReducedClass)[0] # Low pass filter and resize maxFreq = self.maxFreq.get() ts = inputSet.getSamplingRate() K = 0.25 * (maxFreq / ts) if K < 1: K = 1 self.Xdim2 = self.Xdim / K if self.Xdim2 < 32: self.Xdim2 = 32 K = self.Xdim / self.Xdim2 freq = ts / maxFreq ts = K * ts self._insertRunJobStep("xmipp_transform_filter","-i %s -o %s --fourier low_pass %f --oroot %s" %(self.imgsFn,fnOutputReducedClass,freq,fnOutputReducedClassNoExt)) lastId = self._insertRunJobStep("xmipp_image_resize","-i %s --fourier %d -o %s" %(fnOutputReducedClass,self.Xdim2,fnOutputReducedClassNoExt)) # Generate projection gallery from the initial volume if self.initialVolume.hasValue(): lastId = self._insertFunctionStep("projectInitialVolume") return lastId #--------------------------- STEPS functions --------------------------------------------
[docs] def convertInputStep(self, classesFn): inputSet = self.inputSet.get() if isinstance(inputSet, SetOfClasses2D): writeSetOfClasses2D(inputSet, classesFn) else: writeSetOfParticles(inputSet, classesFn)
[docs] def ransacIterationStep(self, n): fnOutputReducedClass = self._getExtraPath("reducedClasses.xmd") fnBase = "ransac%05d"%n fnRoot = self._getTmpPath(fnBase) if self.dimRed: # Get a random sample of images self.runJob("xmipp_transform_dimred","-i %s --randomSample %s.xmd %d -m LTSA "%(fnOutputReducedClass,fnRoot,self.numGrids.get())) else: self.runJob("xmipp_metadata_utilities","-i %s -o %s.xmd --operate random_subset %d --mode overwrite "%(fnOutputReducedClass,fnRoot,self.numSamples.get())) self.runJob("xmipp_metadata_utilities","-i %s.xmd --fill angleRot rand_uniform -180 180 "%(fnRoot)) self.runJob("xmipp_metadata_utilities","-i %s.xmd --fill angleTilt rand_uniform 0 180 "%(fnRoot)) self.runJob("xmipp_metadata_utilities","-i %s.xmd --fill anglePsi rand_uniform 0 360 "%(fnRoot)) # If there is an initial volume, assign angles if self.initialVolume.hasValue(): fnGallery=self._getTmpPath('gallery_InitialVolume.stk') self.runJob("xmipp_angular_projection_matching", "-i %s.xmd -o %s.xmd --ref %s --Ri 0 --Ro %s --max_shift %s --append"\ %(fnRoot,fnRoot,fnGallery,str(self.Xdim/2),str(self.Xdim/20))) # Reconstruct with the small sample self.reconstructStep(fnRoot) fnVol = fnRoot+'.vol' # Generate projections from this reconstruction fnGallery=self._getTmpPath('gallery_'+fnBase+'.stk') self.runJob("xmipp_angular_project_library", "-i %s -o %s --sampling_rate %f --sym %s --method fourier 1 0.25 bspline --compute_neighbors --angular_distance -1 --experimental_images %s --max_tilt_angle 90"\ %(fnVol,fnGallery,self.angularSampling.get(),self.symmetryGroup.get(),fnOutputReducedClass)) # Assign angles to the rest of images fnAngles=self._getTmpPath('angles_'+fnBase+'.xmd') self.runJob("xmipp_angular_projection_matching", "-i %s -o %s --ref %s --Ri 0 --Ro %s --max_shift %s --append"\ %(fnOutputReducedClass,fnAngles,fnGallery,str(self.Xdim/2),str(self.Xdim/20))) # Delete intermediate files cleanPath(fnGallery) cleanPath(self._getTmpPath('gallery_'+fnBase+'_sampling.xmd')) cleanPath(self._getTmpPath('gallery_'+fnBase+'.doc')) cleanPath(fnVol) cleanPath(self._getTmpPath(fnBase+'.xmd'))
[docs] def reconstructStep(self, fnRoot): from pwem.emlib.metadata import getSize if os.path.exists(fnRoot+".xmd"): Nimages=getSize(fnRoot+".xmd") if Nimages>0: if self.useGpu.get(): # protocol will run several reconstructions at once, so execute each reconstruction separately args = "-i %s.xmd -o %s.vol --sym %s --thr %s --fast"\ % (fnRoot, fnRoot, self.symmetryGroup.get(), self.numberOfThreads.get()) #AJ to make it work with and without queue system if self.numberOfMpi.get()>1: N_GPUs = len((self.gpuList.get()).split(',')) args += ' -gpusPerNode %d' % N_GPUs args += ' -threadsPerGPU %d' % max(self.numberOfThreads.get(),4) count=0 GpuListCuda='' if self.useQueueForSteps() or self.useQueue(): GpuList = os.environ["CUDA_VISIBLE_DEVICES"] GpuList = GpuList.split(",") for elem in GpuList: GpuListCuda = GpuListCuda+str(count)+' ' count+=1 else: GpuListAux = '' for elem in self.getGpuList(): GpuListCuda = GpuListCuda+str(count)+' ' GpuListAux = GpuListAux+str(elem)+',' count+=1 os.environ["CUDA_VISIBLE_DEVICES"] = GpuListAux if self.numberOfMpi.get()==1: args += " --device %s" %GpuListCuda if self.numberOfMpi.get()>1: self.runJob('xmipp_cuda_reconstruct_fourier', args, numberOfMpi=len((self.gpuList.get()).split(','))+1) else: self.runJob('xmipp_cuda_reconstruct_fourier', args) else: self.runJob("xmipp_reconstruct_fourier_accel","-i %s.xmd -o %s.vol --sym %s " %(fnRoot,fnRoot,self.symmetryGroup.get())) self.runJob("xmipp_transform_mask","-i %s.vol --mask circular -%d "%(fnRoot,self.Xdim2/2)) else: print(fnRoot+".xmd is empty. The corresponding volume is not generated.")
[docs] def resizeStep(self,fnRoot,Xdim): if os.path.exists(fnRoot+".vol"): self.runJob("xmipp_image_resize","-i %s.vol -o %s.vol --dim %d %d" %(fnRoot,fnRoot,Xdim,Xdim)) self.runJob("xmipp_image_convert","-i %s.vol -o %s.mrc -t vol" %(fnRoot,fnRoot)) cleanPath("%s.vol"%fnRoot) self.runJob("xmipp_image_header", "-i %s.mrc --sampling_rate %f" %\ (fnRoot, self.inputSet.get().getSamplingRate()))
[docs] def getCorrThreshStep(self): corrVector = [] fnCorr=self._getExtraPath("correlations.xmd") mdCorr= emlib.MetaData() for n in range(self.nRansac.get()): fnRoot="ransac%05d"%n fnAngles=self._getTmpPath("angles_"+fnRoot+".xmd") md = emlib.MetaData(fnAngles) for objId in md: corr = md.getValue(emlib.MDL_MAXCC, objId) corrVector.append(corr) objIdCorr = mdCorr.addObject() mdCorr.setValue(emlib.MDL_MAXCC,float(corr),objIdCorr) mdCorr.write("correlations@"+fnCorr,emlib.MD_APPEND) mdCorr= emlib.MetaData() sortedCorrVector = sorted(corrVector) indx = int(floor(self.corrThresh.get()*(len(sortedCorrVector)-1))) #With the line below commented the percentil is not used for the threshold and is used the value introduced in the form #CorrThresh = sortedCorrVector[indx]# objId = mdCorr.addObject() mdCorr.setValue(emlib.MDL_WEIGHT,self.corrThresh.get(),objId) mdCorr.write("corrThreshold@"+fnCorr,emlib.MD_APPEND) print("Correlation threshold: "+str(self.corrThresh.get()))
[docs] def evaluateVolumesStep(self): fnCorr=self._getExtraPath("correlations.xmd") fnCorr = 'corrThreshold@'+fnCorr mdCorr= emlib.MetaData(fnCorr) objId = mdCorr.firstObject() CorrThresh = mdCorr.getValue(emlib.MDL_WEIGHT,objId) for n in range(self.nRansac.get()): fnRoot="ransac%05d"%n fnAngles=self._getTmpPath("angles_"+fnRoot+".xmd") md = emlib.MetaData(fnAngles) numInliers=0 for objId in md: corr = md.getValue(emlib.MDL_MAXCC, objId) if (corr >= CorrThresh) : numInliers = numInliers+corr md= emlib.MetaData() objId = md.addObject() md.setValue(emlib.MDL_WEIGHT,float(numInliers),objId) md.write("inliers@"+fnAngles,emlib.MD_APPEND)
[docs] def getBestVolumesStep(self): volumes = [] inliers = [] for n in range(self.nRansac.get()): fnAngles = self._getTmpPath("angles_ransac%05d"%n+".xmd") md=emlib.MetaData("inliers@"+fnAngles) numInliers=md.getValue(emlib.MDL_WEIGHT,md.firstObject()) volumes.append(fnAngles) inliers.append(numInliers) index = sorted(range(inliers.__len__()), key=lambda k: inliers[k]) fnBestAngles = '' threshold=self.getCCThreshold() i = self.nRansac.get()-1 indx = 0 while i >= 0 and indx < self.numVolumes: fnBestAngles = volumes[index[i]] fnBestAnglesOut = self._getPath("proposedVolume%05d"%indx+".xmd") copyFile(fnBestAngles, fnBestAnglesOut)"Best volume %d = %s" % (indx, fnBestAngles)) if not self.useAll: self.runJob("xmipp_metadata_utilities","-i %s -o %s --query select \"maxCC>%f \" --mode append" %(fnBestAnglesOut,fnBestAnglesOut,threshold)) if not isMdEmpty(fnBestAnglesOut): indx += 1 else: indx += 1 i -= 1 # Remove unnecessary files for n in range(self.nRansac.get()): fnAngles = self._getTmpPath("angles_ransac%05d"%n+".xmd") cleanPath(fnAngles)
[docs] def projMatchStep(self,fnBase): fnRoot=self._getPath(fnBase) if os.path.exists(fnRoot+".vol"): fnGallery=self._getTmpPath('gallery_'+fnBase+'.stk') fnOutputReducedClass = self._getExtraPath("reducedClasses.xmd") AngularSampling=max(self.angularSampling.get()/2.0,7.5); self.runJob("xmipp_angular_project_library", "-i %s.vol -o %s --sampling_rate %f --sym %s --method fourier 1 0.25 bspline --compute_neighbors --angular_distance -1 --experimental_images %s"\ %(fnRoot,fnGallery,float(AngularSampling),self.symmetryGroup.get(),fnOutputReducedClass)) self.runJob("xmipp_angular_projection_matching", "-i %s.xmd -o %s.xmd --ref %s --Ri 0 --Ro %s --max_shift %s --append"\ %(fnRoot,fnRoot,fnGallery,str(self.Xdim/2),str(self.Xdim/20))) cleanPath(self._getTmpPath('gallery_'+fnBase+'_sampling.xmd')) cleanPath(self._getTmpPath('gallery_'+fnBase+'.doc')) cleanPath(self._getTmpPath('gallery_'+fnBase+'.stk'))
[docs] def scoreFinalVolumes(self): threshold=self.getCCThreshold() mdOut=emlib.MetaData() for n in range(self.numVolumes.get()): fnRoot=self._getPath('proposedVolume%05d'%n) fnAssignment=fnRoot+".xmd" if os.path.exists(fnAssignment): self.runJob("xmipp_metadata_utilities","-i %s --fill weight constant 1"%fnAssignment) MDassignment=emlib.MetaData(fnAssignment) sum=0 thresholdedSum=0 N=0 minCC=2 for id in MDassignment: cc=MDassignment.getValue(emlib.MDL_MAXCC,id) sum+=cc thresholdedSum+=cc-threshold if cc<minCC: minCC=cc N+=1 if N>0: avg=sum/N else: avg=0.0 id=mdOut.addObject() mdOut.setValue(emlib.MDL_IMAGE,fnRoot+".mrc",id) mdOut.setValue(emlib.MDL_VOLUME_SCORE_SUM,float(sum),id) mdOut.setValue(emlib.MDL_VOLUME_SCORE_SUM_TH,float(thresholdedSum),id) mdOut.setValue(emlib.MDL_VOLUME_SCORE_MEAN,float(avg),id) mdOut.setValue(emlib.MDL_VOLUME_SCORE_MIN,float(minCC),id) mdOut.write(self._getPath("proposedVolumes.xmd"))
[docs] def projectInitialVolume(self): fnOutputInitVolume=self._getTmpPath("initialVolume.vol") img = ImageHandler() img.convert(self.initialVolume.get(), fnOutputInitVolume) self.runJob("xmipp_image_resize","-i %s --dim %d %d"%(fnOutputInitVolume,self.Xdim2,self.Xdim2)) fnGallery=self._getTmpPath('gallery_InitialVolume.stk') fnOutputReducedClass = self._getExtraPath("reducedClasses.xmd") self.runJob("xmipp_angular_project_library", "-i %s -o %s --sampling_rate %f --sym %s --method fourier 1 0.25 bspline --compute_neighbors --angular_distance -1 --experimental_images %s"\ %(fnOutputInitVolume,fnGallery,self.angularSampling.get(),self.symmetryGroup.get(),fnOutputReducedClass))
def _postprocessVolume(self, vol, row): self._counter += 1 vol.setObjComment('ransac volume %02d' % self._counter) vol._xmipp_volScoreSum = Float(row.getValue(emlib.MDL_VOLUME_SCORE_SUM)) vol._xmipp_volScoreSumTh = Float(row.getValue(emlib.MDL_VOLUME_SCORE_SUM_TH)) vol._xmipp_volScoreMean = Float(row.getValue(emlib.MDL_VOLUME_SCORE_MEAN)) vol._xmipp_volScoreMin = Float(row.getValue(emlib.MDL_VOLUME_SCORE_MIN))
[docs] def createOutputStep(self): inputSet = self.inputSet.get() fn = self._getPath('proposedVolumes.xmd') # md = emlib.MetaData(fn) # md.addItemId() # md.write(fn) volumesSet = self._createSetOfVolumes() volumesSet.setSamplingRate(inputSet.getSamplingRate()) self._counter = 0 readSetOfVolumes(fn, volumesSet, postprocessImageRow=self._postprocessVolume) # Set a meaningful comment # for vol in volumesSet: # vol.setObjComment('ransac volume %02d' % vol.getObjId()) # volumesSet.update(vol) self._defineOutputs(outputVolumes=volumesSet) self._defineSourceRelation(self.inputSet, volumesSet) self._storeSummaryInfo(self.numVolumes.get())
#--------------------------- INFO functions -------------------------------------------- def _validate(self): errors = [] inputSet = self.inputSet.get() if isinstance(inputSet, SetOfClasses2D): if not self.inputSet.get().hasRepresentatives(): errors.append("The input classes should have representatives.") if self.dimRed: nGrids = self.numGrids.get() if (nGrids * nGrids) > inputSet.getSize(): errors.append('Dimensionaly reduction could not be applied') errors.append('if the number of classes is less than the number') errors.append('of grids squared. \n') errors.append('Consider either provide more classes or') errors.append('disable dimensionality reduction') if self.useGpu and not isXmippCudaPresent(): errors.append("You have asked to use GPU, but I cannot find Xmipp GPU programs in the path") return errors def _summary(self): summary = [] if hasattr(self, 'outputVolumes'): summary.append("RANSAC iterations: %d" % self.nRansac) summary.append("Number of volumes to refine: %d" % self.numVolumes.get()) summary.append("Number of refinement interations: %d" % self.numIter.get()) if self.summaryVar.hasValue(): summary.append(self.summaryVar.get()) else: summary.append("Output volumes not ready yet.") return summary def _methods(self): strline='' if hasattr(self, 'outputVolumes'): strline+='We obtained %d initial volume(s) from %s set of images and symmetry %s.'%\ (self.numVolumes.get(),self.getObjectTag('inputSet'),self.symmetryGroup.get()) strline+='The number of RANSAC volumes generated are %d.From this set, we selected the best %d volume(s) that was refined by %d projection matching iteration(s)'%\ (self.nRansac.get(),self.numVolumes.get(),self.numIter.get()) strline+= ' [Vargas2014]' if self.dimRed: strline+='We performed dimensionality reduction using a %d x %d grid'%\ (self.numGrids.get(),self.numGrids.get()) return [strline] #--------------------------- UTILS functions --------------------------------------------
[docs] def getCCThreshold(self): fnCorr = self._getExtraPath("correlations.xmd") mdCorr = emlib.MetaData("corrThreshold@"+fnCorr) return mdCorr.getValue(emlib.MDL_WEIGHT, mdCorr.firstObject())
def _storeSummaryInfo(self, numVolumes): """ Store some information when the protocol finishes. """ msg1 = '' msg2 = '' for n in range(numVolumes): fnBase = 'proposedVolume%05d' % n fnRoot = self._getPath(fnBase + ".xmd") if os.path.isfile(fnRoot): md = emlib.MetaData(fnRoot) size = md.size() if (size < 5): msg1 = "Num of inliers for model %d too small and equal to %d \n" % (n, size) msg1 += "Decrease the value of Inlier Threshold parameter and run again \n" fnRoot = self._getTmpPath("ransac00000.xmd") if os.path.isfile(fnRoot): md = emlib.MetaData(fnRoot) size = md.size() if (size < 5): msg2 = "Num of random samples too small and equal to %d.\n" % size msg2 += "If the option Dimensionality reduction is on, increase the number of grids per dimension (In this case we recommend to put Dimensionality reduction off).\n" msg2 += "If the option Dimensionality reduction is off, increase the number of random samples.\n" msg = msg1 + msg2 self.summaryVar.set(msg) def _citations(self): return ['Vargas2014']