示例#1
0
def mask_cti(image, CTI, ctiDict, verbose=0):
    """Function to mask the region affected by a lightbulb"""

    if ctiDict['isCTI']:
        sec = section2slice(image['DATASEC' + CTI['amp']])
        image.mask[sec] |= BADPIX_BADAMP

    logger.info(' CTI: mask applied to image')

    return image
    def __call__(cls, image):
        """Convert pixel values from ADU to electrons, including weight or variance
        image and critical keywords.

        :Parameters:
            - `image`: the DESImage for pixel values to be converted

        Applies the correction "in place"
        """

        logger.info('Gain Correcting Image')

        saturate = 0.
        gains = []
        for amp in decaminfo.amps:
            sec = section2slice(image['DATASEC' + amp])
            gain = image['GAIN' + amp]
            gains.append(gain)
            image.data[sec] *= gain

            # Adjust the weight or variance image if present:
            if image.weight is not None:
                image.weight[sec] *= 1. / (gain * gain)
            if image.variance is not None:
                image.variance[sec] *= gain * gain

            # Adjust keywords
            image['GAIN' + amp] = image['GAIN' + amp] / gain
            image['SATURAT' + amp] = image['SATURAT' + amp] * gain
            saturate = max(saturate, image['SATURAT' + amp])
            # Scale the SKYVAR if it's already here
            kw = 'SKYVAR' + amp
            if kw in image.header.keys():
                image[kw] = image[kw] * gain * gain
            # The FLATMED will keep track of rescalings *after* gain:
            image['FLATMED' + amp] = 1.

        # The SATURATE keyword is assigned to maximum of the two amps.
        image['SATURATE'] = saturate

        # Some other keywords that we will adjust crudely with mean gain
        # if they are present:
        gain = np.mean(gains)
        for kw in ('SKYBRITE', 'SKYSIGMA'):
            if kw in image.header.keys():
                image[kw] = image[kw] * gain

        # One other keyword to adjust:
        image['BUNIT'] = 'electrons'

        logger.debug('Finished applying Gain Correction')
        ret_code = 0
        return ret_code
示例#3
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    def __call__(cls, image, dome):
        """Add a weight plane

        :Parameters:
            - `image`: the DESImage for weight plane to be added

        Applies "in place"
        """

        logger.info('Adding Weight Image')

        if image.weight is None:
            image.init_weight()
            # Check that dome and data are from same CCD
            try:
                items_must_match(image, dome, 'CCDNUM')
            except:
                return 1
            # Transform the sky image into a variance image
            data = image.data
            var = np.array(data, dtype=weight_dtype)
            for amp in decaminfo.amps:
                sec = section2slice(image['DATASEC' + amp])
                invgain = (image['FLATMED' + amp] /
                           image['GAIN' + amp]) / dome.data[sec]
                var[sec] += image['RDNOISE' + amp]**2 * invgain
                var[sec] *= invgain
            # Add noise from the dome flat shot noise, if present
            if dome.weight is not None:
                var += data * data / (dome.weight * dome.data * dome.data)
            elif dome.variance is not None:
                var += data * data * dome.variance / (dome.data * dome.data)

            image.weight = 1.0 / var
            logger.info('Finished building a weight plane')
        else:
            logger.info('Weight plane already present... skipping.')

        ret_code = 0
        return ret_code
示例#4
0
def check_cti(image, CTI, verbose=0):
    """Function to check for presence of CTI"""

#
#   Initialize ctiDict
#
    ctiDict = {'isCTI': False}
    ctiDict['expnum'] = image['EXPNUM']

    # Also create the BAND and NITE keywords if they are not present
    try:
        image['BAND']
    except:
        image['BAND'] = decaminfo.get_band(image['FILTER'])
    try:
        image['NITE']
    except:
        image['NITE'] = decaminfo.get_nite(image['DATE-OBS'])

    band = image['BAND'].strip()
    sec = section2slice(image['DATASEC' + CTI['amp']])
#
#   This could become useful if it is necessary to start examining the opposite amplifier in
#   conjunction with the amplifier that is having a problem
#
#    if (CTI['amp']=="A"):
#        osec = section2slice(image['DATASEC'+'B'])
#    else:
#        osec = section2slice(image['DATASEC'+'A'])

    maxiter = 10
    converge_num = 0.0001
    clipsig = 3.0

    clip_avg, clip_med, clip_std = lb.medclip(image.data[sec], clipsig, maxiter, converge_num, verbose=0)
    logger.info(' CTI: Global(clipped): median = {:.3f}, stddev = {:.3f} '.format(clip_med, clip_std))
    ctiDict['cmed'] = float(clip_med)
    ctiDict['cstd'] = float(clip_std)
    clow = clip_med - (3.0 * clip_std)
    ctiDict['clow'] = float(clow)

#    oclip_avg,oclip_med,oclip_std=medclip(image.data[osec],clipsig,maxiter,converge_num,verbose)
#    print(" Global(oclipped): median = {:.3f}, stddev = {:.3f} ".format(oclip_med,oclip_std))
#    oclow=oclip_med-(3.0*oclip_std)

#
#   Obtain row-by-row median to look for horizontal striping (also needed to check/reject edgebleeds)
#
    row_med = np.median(image.data[sec], axis=1)
    wsm = np.where(row_med < clow)
    nrow_low = row_med[wsm].size
#
#   Hacky attempt to check for edge-bleed
#
    iedge = [4, 4091]
    while row_med[iedge[0]] < clow:
        iedge[0] = iedge[0] + 1
    while row_med[iedge[1]] < clow:
        iedge[1] = iedge[1] - 1
    if iedge[0] == 4:
        iedge[0] = 0
    if iedge[1] == 4091:
        iedge[1] = 4095
    nrow_edge = 4096 - (iedge[1] - iedge[0] + 1)
    logger.info(' CTI: Number of low rows: {:d} (nrow_edge={:d}) '.format(nrow_low, nrow_edge))

#
#   Blank out pixels that are below the 3-sigma level with respect to median
#   This removes power from vertical stripes
#
    wsm = np.where(image.data[sec] < clow)
    npix_low = image.data[sec][wsm].size
    logger.info(' CTI: Number of low pixels: {:d} '.format(npix_low))
    u = image.data[sec] - clip_med
    u[wsm] = 0.0
#
#   Harder cut currently not needed.  If used this would get rid of all pixels below the median level
#   (effectively this reduces the amount that noise suppresses contrast of the auto-correlation signal from CTI)
#
#    wsm=np.where(u<0.)
#    npix_zero=u[wsm].size
#    logger.info(' CTI: Number of sub-zero pixels: {:d} '.format(npix_zero))
#    u[wsm]=0.0

#
#   Calculate a set of auto-correlations by sampling lags in the x-direction and
#       then two diaganol sets at PA=+/-45 degrees
#   Note: y-direction lags would be succeptible to both bad columns and bleeds.
#   These are normalized by the auto-correlation with lag 0 (defined as 'a' below).
#   Take a maximum lag that will be calculated and use that to trim the image.
#   Note: This both gets rid of most edge-effects automatically but also removes the need to calculate an effective normalization for higher lags
#
    maxlag = 100
    lagList = [0, 1, 3, 5, 7, 11, 15, 19, 23, 31, 37, 45]

    a = np.sum(u[maxlag:-maxlag, maxlag:-maxlag] * u[maxlag:-maxlag, maxlag:-maxlag])
#    b=np.sum(v[maxlag:-maxlag,maxlag:-maxlag]*v[maxlag:-maxlag,maxlag:-maxlag])
    x = [1.0]
    d1 = [1.0]
    d2 = [1.0]
#    vx=[1.0]
#    vd1=[1.0]
#    vd2=[1.0]
#
#   More lags than those sampled are needed because the diagonal (PA=+/-45) measures will need to be interpolated
#   for comaparison to lags in the x-direction.
#

    for lag in lagList:
        if lag != 0:
            x.append(np.sum(u[maxlag:-maxlag, maxlag:-maxlag] * u[maxlag:-maxlag, maxlag - lag:-maxlag - lag]) / a)
            d1.append(np.sum(u[maxlag:-maxlag, maxlag:-maxlag] * u[maxlag-lag:-maxlag - lag, maxlag - lag:-maxlag - lag]) / a)
            d2.append(np.sum(u[maxlag:-maxlag, maxlag:-maxlag] * u[maxlag-lag:-maxlag - lag, maxlag + lag:-maxlag + lag]) / a)
#            vx.append(np.sum(v[maxlag:-maxlag,maxlag:-maxlag]*v[maxlag:-maxlag,maxlag-lag:-maxlag-lag])/b)
#            vd1.append(np.sum(v[maxlag:-maxlag,maxlag:-maxlag]*v[maxlag-lag:-maxlag-lag,maxlag-lag:-maxlag-lag])/b)
#            vd2.append(np.sum(v[maxlag:-maxlag,maxlag:-maxlag]*v[maxlag-lag:-maxlag-lag,maxlag+lag:-maxlag+lag])/b)

    data = {'lag': np.array(lagList),
            'x': np.array(x),
            'd1': np.array(d1),
            'd2': np.array(d2)
#          'vx':np.array(vx),
#          'vd1':np.array(vd1),
#          'vd2':np.array(vd2)
           }

    r2 = np.sqrt(2.0)
    l1 = data['lag']
    l2 = data['lag'] * r2
    x1 = data['x']
    d1i = np.interp(data['lag'], l2, data['d1'])
    d2i = np.interp(data['lag'], l2, data['d2'])
    rd1 = data['x'] / d1i
    rd2 = data['x'] / d2i

#    vx1=data['vx']
#    vd1i=np.interp(data['lag'],l2,data['vd1'])
#    vd2i=np.interp(data['lag'],l2,data['vd2'])
#    vrd1=data['vx']/vd1i
#    vrd2=data['vx']/vd2i
##    vdx=data['x']/data['vx']
#    vdx=(rd1+rd2)/(vrd1+vrd2)

    logger.info(' CTI: lags {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(l1[3], l1[4], l1[6], l1[8], l1[10]))
    logger.info(' CTI:  lx  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(x1[3], x1[4], x1[6], x1[8], x1[10]))
    logger.info(' CTI: d1i  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(d1i[3], d1i[4], d1i[6], d1i[8], d1i[10]))
    logger.info(' CTI: d2i  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(d2i[3], d2i[4], d2i[6], d2i[8], d2i[10]))
    logger.info(' CTI: ld1  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(rd1[3], rd1[4], rd1[6], rd1[8], rd1[10]))
    logger.info(' CTI: ld2  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(rd2[3], rd2[4], rd2[6], rd2[8], rd2[10]))
#    logger.info(' CTI: lvx  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(vx1[3],vx1[4],vx1[6],vx1[8],vx1[10]))
#    logger.info(' CTI:vd1i  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(vd1i[3],vd1i[4],vd1i[6],vd1i[8],vd1i[10]))
#    logger.info(' CTI:vd2i  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(vd2i[3],vd2i[4],vd2i[6],vd2i[8],vd2i[10]))
#    logger.info(' CTI:vld1  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(vrd1[3],vrd1[4],vrd1[6],vrd1[8],vrd1[10]))
#    logger.info(' CTI:vld2  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(vrd2[3],vrd2[4],vrd2[6],vrd2[8],vrd2[10]))
#    logger.info(' CTI:vdx0  {:8.2f} {:8.2f} {:8.2f} {:8.2f} {:8.2f} '.format(vdx[3],vdx[4],vdx[6],vdx[8],vdx[10]))

#
#   Set band dependent thresholds...
#   Note the criteria used are based on an empirical study of the one example we currently have (CCD=41, Y6)
#
    nrow_lim = 5
    if band != "Y":
        cclim = 0.9
    else:
        cclim = 1.15
#
#   Now check and set flag based on empirical critera.
#       First are the horizontal streaks that can appear...
#       Second are the comparison of the auto-correlation in the x and average of the diaganol directrions
#
    flag_cti = False
    if nrow_low - nrow_edge >= nrow_lim:
        flag_cti = True

    avg_rd = (rd1 + rd2) / 2.0
    if avg_rd[3] > cclim and avg_rd[4] > cclim and avg_rd[6] > cclim:
        flag_cti = True

    if flag_cti:
        ctiDict['isCTI'] = True

    return ctiDict
示例#5
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    def __call__(cls, image, fit_filename, pc_filename, weight, dome,
                 skymodel_filename):
        """
        Subtract sky from image using previous principal-components fit. Optionally
        build weight image from fitted sky or all counts, in which case the dome flat
        is needed and proper gain values are expected in the image header.

        :Parameters:
            - `image`: DESImage that has been flattened with dome already and fit
            - `fit_filename`: filename with the coefficients from minisky fitting.  Sky
                              subtraction is skipped if this is None.
            - `pc_filename`: filename for the stored full-res sky principal components
            - `weight`: 'none' to skip weights, 'sky' to calculate weight at sky level,
                         'all' to use all counts
            - `dome`: DESImage for the dome flat, needed if weight is not 'none'.
            - `skymodel_filename`: optional output filename for 'sky'
        """

        if weight == 'sky' and fit_filename is None:
            raise SkyError(
                'Cannot make sky-only weight map without doing sky subtraction'
            )

        if fit_filename is not None:
            logger.info('Subtracting sky')
            mini = skyinfo.MiniDecam.load(fit_filename)
            templates = skyinfo.SkyPC.load(pc_filename)
            if templates.detpos != image['DETPOS']:
                # Quit if we don't have the right CCD to subtract
                logger.error(
                    'Image DETPOS {:s} does not match sky template {:s}'.
                    format(templates.detpos, image['DETPOS']))
                return 1
            try:
                image['BAND']
            except:
                image['BAND'] = decaminfo.get_band(image['FILTER'])
            try:
                items_must_match(image, mini.header, 'BAND', 'EXPNUM')
                items_must_match(image, templates.header, 'BAND')
                # ??? Could check that template and image use same dome flat
            except:
                return 1
            sky = templates.sky(mini.coeffs)
            image.data -= sky
            image.write_key('SKYSBFIL',
                            path.basename(pc_filename),
                            comment='Sky subtraction template file')
            for i, c in enumerate(mini.coeffs):
                image.write_key('SKYPC{:>02d}'.format(i),
                                c,
                                comment='Sky template coefficient')
            logger.info('Finished sky subtraction')
            #
            #           Optionally write the sky model that was subtracted from the image.
            #
            if skymodel_filename is not None:
                # Create HDU for output skymodel, add some header info, save output to file
                logger.info('Optional output of skymodel requested')
                skymodel_image = DESDataImage(sky)
                skymodel_image.write_key(
                    'SKYSBFIL',
                    path.basename(pc_filename),
                    comment='Sky subtraction template file')
                for i, c in enumerate(mini.coeffs):
                    skymodel_image.write_key(
                        'SKYPC{:>02d}'.format(i),
                        c,
                        comment='Sky template coefficient')
                skymodel_image.write_key('BAND', image['BAND'], comment='Band')
                skymodel_image.write_key('EXPNUM',
                                         image['EXPNUM'],
                                         comment='Exposure Number')
                skymodel_image.write_key('CCDNUM',
                                         image['CCDNUM'],
                                         comment='CCD Number')
                skymodel_image.write_key('NITE',
                                         image['NITE'],
                                         comment='Night')
                #               skymodel_image.copy_header_info(image, cls.propagate, require=False)
                ## ?? catch exception from write error below?
                skymodel_image.save(skymodel_filename)

        else:
            sky = None

        if weight == 'none':
            do_weight = False
            sky_weight = False
        elif weight == 'sky':
            do_weight = True
            sky_weight = True
        elif weight == 'all':
            do_weight = True
            sky_weight = False
        else:
            raise SkyError('Invalid weight value: ' + weight)

        if do_weight:
            if dome is None:
                raise SkyError(
                    'sky_subtract needs dome flat when making weights')

            if sky_weight:
                logger.info('Constructing weight image from sky image')
                data = sky
            else:
                logger.info('Constructing weight image from all counts')
                if sky is None:
                    # If we did not subtract a sky, the image data gives total counts
                    data = image.data
                else:
                    # Add sky back in to get total counts
                    data = image.data + sky

            if image.weight is not None or image.variance is not None:
                image.weight = None
                image.variance = None
                logger.warning('Overwriting existing weight image')
            """
            We assume in constructing the weight (=inverse variance) image that
            the input image here has been divided by the dome flat already, and that
            its GAIN[AB] keywords are correct for a pixel that has been divided
            by the FLATMED[AB] of the flat image.  So the number of *electrons* that
            were read in a pixel whose current value=sky is
            e = sky * (dome/FLATMED) * GAIN


            The variance has three parts: read noise, and sky Poisson noise, and
            multiplicative errors from noise in the flat field.
            The read noise variance, in electrons, is
            Var = RDNOISE^2
            ...and the shot noise from sky was, in electrons,
            Var = sky * (dome/FLATMED) * GAIN

            This means the total variance in the image, in its present form, is

            Var = (RDNOISE * FLATMED / dome / GAIN)^2 + (FLATMED/GAIN)*sky/dome

            We can also add the uncertainty propagated from shot noise in the dome flat,
            if the dome image has a weight or variance.  In which case we would add

            Var += var(dome) * sky^2 / dome^2

            (remembering that sky has already been divided by the dome).

            If sky_weight = False, we can substitute the image data for sky in the above
            calculations.
            """

            # Transform the sky image into a variance image
            var = np.array(data, dtype=weight_dtype)
            for amp in decaminfo.amps:
                sec = section2slice(image['DATASEC' + amp])
                invgain = (image['FLATMED' + amp] /
                           image['GAIN' + amp]) / dome.data[sec]
                var[sec] += image['RDNOISE' + amp]**2 * invgain
                var[sec] *= invgain
            # Add noise from the dome flat shot noise, if present
            if dome.weight is not None:
                var += data * data / (dome.weight * dome.data * dome.data)
            elif dome.variance is not None:
                var += data * data * dome.variance / (dome.data * dome.data)

            image.variance = var

            # Now there are statistics desired for the output image header.
            # First, the median variance at sky level on the two amps, SKYVAR[AB]
            meds = []
            for amp in decaminfo.amps:
                sec = section2slice(image['DATASEC' + amp])
                v = np.median(var[sec][::4, ::4])
                image.write_key(
                    'SKYVAR' + amp,
                    v,
                    comment='Median noise variance at sky level, amp ' + amp)
                meds.append(v)
            # SKYSIGMA is overall average noise level
            image.write_key('SKYSIGMA',
                            np.sqrt(np.mean(meds)),
                            comment='RMS noise at sky level')
            # SKYBRITE is a measure of sky brightness.  Use the sky image if we've got it, else
            # use the data
            if sky is None:
                skybrite = np.median(data[::4, ::4])
            else:
                skybrite = np.median(sky[::2, ::2])
            image.write_key('SKYBRITE',
                            skybrite,
                            comment='Median sky brightness')

            logger.debug('Finished weight construction')

            # Run null_mask or resaturate if requested in the command-line
            if cls.do_step('null_mask') or cls.do_step('resaturate'):
                logger.info("Running null_weights")
                # We need to fix the step_name if we want to call 'step_run'
                null_weights.__class__.step_name = config_section
                #null_weights.__class__.step_name = cls.config_section
                null_weights.step_run(image, cls.config)

        ret_code = 0
        return ret_code
示例#6
0
    def _doit(cls, image, flat_im):
        """Apply a flat field correction to an image - used for both dome
        and star flats.

        :Parameters:
            - `image`: the DESImage to apply a bias correction
            - `flat_im`:  the flat correction image to apply

        Applies the correction "in place"
        """
        logger.info('Applying Flat')

        # Check that flat and data are from same CCD and filter
        try:
            image['BAND']
        except:
            # Give image a BAND from its FILTER if it's not there
            image['BAND'] = decaminfo.get_band(image['FILTER'])
        try:
            items_must_match(image, flat_im, 'CCDNUM', 'BAND')
        except:
            return 1

        # Apply flat to the data
        image.data /= flat_im.data

        # Update variance or weight image if it exists
        if image.weight is not None:
            image.weight *= flat_im.data * flat_im.data
        if image.variance is not None:
            image.variance /= flat_im.data * flat_im.data

        # If mask image exists, mark as BADPIX_BPM any pixels that have
        # non-positive flat and are not already flagged.
        if image.mask is not None:
            # Find flat-field pixels that are invalid but not already bad for
            # one of these reasons:
            badmask = maskbits.BADPIX_BPM +\
                maskbits.BADPIX_BADAMP +\
                maskbits.BADPIX_EDGE
            badflat = np.logical_and(flat_im.data <= 0., image.mask & badmask)
            mark_these = np.where(badflat.flatten())[0]
            image.mask.flatten()[mark_these] |= maskbits.BADPIX_BPM

        # If a weight or variance image already exists, add to it any additional
        # variance from the flat:
        if (image.weight is not None or image.variance is not None):
            if flat_im.weight is not None:
                var = image.get_variance()
                f2 = flat_im.data * flat_im.data
                var *= f2
                var += image.data * image.data / (flat_im.weight * f2)
            elif flat_im.variance is not None:
                var = image.get_variance()
                f2 = flat_im.data * flat_im.data
                var *= f2
                var += image.data * image.data * flat_im.variance / f2

        # Update header keywords for rescaling
        saturate = 0.
        scales = []
        for amp in decaminfo.amps:
            # Acquire the typical scaling factor for each amp from the flat
            scalekw = 'FLATMED' + amp
            if scalekw in flat_im.header.keys():
                # Already stored in the flat's header:
                scale = flat_im[scalekw]
            else:
                # Figure it out ourselves from median of a subsample:
                #                sec = DESImage.section2slice(image['DATASEC'+amp])
                sec = section2slice(image['DATASEC' + amp])
                scale = np.median(flat_im.data[sec][::4, ::4])
            scales.append(scale)
            if scalekw in image.header.keys():
                # Add current scaling to any previous ones
                image[scalekw] = image[scalekw] * scale
            else:
                image[scalekw] = scale
            image['GAIN' + amp] = image['GAIN' + amp] * scale
            image['SATURAT' + amp] = image['SATURAT' + amp] / scale
            # Scale the SKYVAR if it's already here
            kw = 'SKYVAR' + amp
            if kw in image.header.keys():
                image[kw] = image[kw] / (scale * scale)
            saturate = max(saturate, image['SATURAT' + amp])
        # The SATURATE keyword is assigned to maximum of the amps' values.
        image['SATURATE'] = saturate

        # Some other keywords that we will adjust crudely with mean rescaling
        # if they are present:
        scale = np.mean(scales)
        for kw in ('SKYBRITE', 'SKYSIGMA'):
            if kw in image.header.keys():
                image[kw] = image[kw] / scale

        logger.debug('Finished applying Flat')
        ret_code = 0
        return ret_code
示例#7
0
    def __call__(cls, image, fname_lincor):
        """Apply a linearity correction

        :Parameters:
            - `image`: the DESImage to determine and apply an ovescan correction
            - `fname_lincor`: the linearity correction FITS table (contains look-up tables)

        Applies the correction "in place"
        """

        #
        #       Discover the HDU in the linearity correction FITS table that contains data for a specific CCD
        #
        fits_inventory = DESFITSInventory(fname_lincor)
        lincor_hdu = fits_inventory.ccd_hdus(image['CCDNUM'])
        if len(lincor_hdu) != 1:
            if not lincor_hdu:
                logger.error(
                    'Unable to locate HDU in %s containing linearity correction for CCDNUM %d. Aborting!',
                    fname_lincor, image['CCDNUM'])
            else:
                logger.error(
                    'Found multiple HDUs in %s containing linearity correction for CCDNUM %d. Aborting!',
                    fname_lincor, image['CCDNUM'])
            raise Exception()

        logger.info('Reading Linearity Correction from %s', fname_lincor)
        cat_fits = fitsio.FITS(fname_lincor, 'r')
        cat_hdu = lincor_hdu[0]
        cols_retrieve = ["ADU", "ADU_LINEAR_A", "ADU_LINEAR_B"]
        CAT = cat_fits[cat_hdu].read(columns=cols_retrieve)
        #
        #        If columns do not get put into CAT in a predefined order then these utilities
        #        may be needed.  RAG has them and can implement... left this way for now since it
        #        currently duplicates imcorrect exactly
        #
        #        CATcol=cat_fits[cat_hdu].get_colnames()
        #        cdict=MkCatDict(CATcol,cols_retrieve)

        #
        #       Define the correction being made.
        #
        nonlinear = []
        linearA = []
        linearB = []
        for row in CAT:
            nonlinear.append(row[0])
            linearA.append(row[1])
            linearB.append(row[2])
        nonlinear = np.array(nonlinear)
        linearA = np.array(linearA)
        linearB = np.array(linearB)
        interpA = interpolate.interp1d(nonlinear,
                                       linearA,
                                       kind='linear',
                                       copy=True)
        interpB = interpolate.interp1d(nonlinear,
                                       linearB,
                                       kind='linear',
                                       copy=True)
        logger.info('Applying Linearity Correction')

        #
        #       Slice over the datasecs for each amplifier.
        #       Apply the correction
        #
        seca = section2slice(image['DATASECA'])
        secb = section2slice(image['DATASECB'])

        # Only fix pixels that are in the range of the nonlinearity table
        in_range = np.logical_and(image.data[seca] >= np.min(nonlinear),
                                  image.data[seca] <= np.max(nonlinear))
        image.data[seca][in_range] = interpA(image.data[seca][in_range])

        in_range = np.logical_and(image.data[secb] >= np.min(nonlinear),
                                  image.data[secb] <= np.max(nonlinear))
        image.data[secb][in_range] = interpB(image.data[secb][in_range])

        image.write_key('LINCFIL',
                        path.basename(fname_lincor),
                        comment='Nonlinearity correction file')

        ret_code = 0
        return ret_code
示例#8
0
    def __call__(cls, image, bffile, bfmask):
        """
        Apply brighter-fatter correction to an image, and set BADPIX_SUSPECT bit
        in mask image for pixels adjacent to those with unknown collected charge.

        :Parameters:
            - `image`: the DESImage to operate upon.  Must have mask plane present.
            - `bffile`: name of FITS file holding the brighter-fatter coefficients
            - `bfmask`: which bits in the mask will trigger pixel being ignored - should
                        denote those pixels having unknown amount of charge during integration.
        """

        logger.info('Start brighter-fatter correction')

        if image.mask is None:
            raise BFError("Missing mask image for bf_correct")

        detpos = image['DETPOS'].strip()
        logger.info('reading BF corrections from %s' % bffile)
        bf = BFKernel(bffile, detpos)

        ignore = np.logical_or(np.isinf(image.data), np.isnan(image.data))
        ignore = np.logical_or(ignore, (image.mask & bfmask) != 0)

        # Get a median sky level and replace bad pixels with it when deriving kernel
        # Also put image into electron units, if not already.
        data = np.array(image.data)
        for amp in decaminfo.amps:
            gain = image['GAIN' + amp]
            sec = section2slice(image['DATASEC' + amp])
            if gain != 1:
                data[sec] *= gain
            sky = np.median(data[sec][::4, ::4])
            data[sec][ignore[sec]] = sky

        # Convolve data with R kernel to get right-hand pixel shifts
        df = np.fft.rfft2(data)
        kernel = bf.kernelR(data.shape)
        shift = np.fft.irfft2(df * np.fft.rfft2(kernel))
        # Multiply by border charge to get amount of charge to move.
        charge = 0.5 * (data[:, :-1] + data[:, 1:]) * shift[:, :-1]
        # Do not shift charge into or out of bad pixels
        charge[ignore[:, :-1]] = 0.
        charge[ignore[:, 1:]] = 0.

        # Adjust data for this shift
        out = np.array(image.data)
        for amp in decaminfo.amps:
            # Redo the temporary gain correction:
            gain = image['GAIN' + amp]
            sec = section2slice(image['DATASEC' + amp])
            if gain != 1:
                out[sec] *= gain
        out[:, 1:] -= charge
        out[:, :-1] += charge

        # Now do the upper-edge pixel shifts  ??? Add gain factor here & T?
        kernel = bf.kernelT(data.shape)
        shift = np.fft.irfft2(df * np.fft.rfft2(kernel))
        # Multiply by border charge to get amount of charge to move.
        charge = 0.5 * (data[:-1, :] + data[1:, :]) * shift[:-1, :]
        # Do not shift charge into or out of bad pixels
        charge[ignore[:-1, :]] = 0.
        charge[ignore[1:, :]] = 0.
        # Adjust data for this shift
        out[1:, :] -= charge
        out[:-1, :] += charge

        # Undo the gain correction if we made it originally:
        for amp in decaminfo.amps:
            gain = image['GAIN' + amp]
            sec = section2slice(image['DATASEC' + amp])
            if gain != 1.:
                out[sec] /= gain
        image.data = out

        # Set the SUSPECT flag for all pixels that were adjacent to
        # ignored pixels, as their b/f correction is off
        change_mask = np.zeros(image.mask.shape, dtype=bool)
        change_mask[:-1, :] |= ignore[1:, :]  # mask below
        change_mask[1:, :] |= ignore[:-1, :]  # mask above
        change_mask[:, :-1] |= ignore[:, 1:]  # mask to left
        change_mask[:, 1:] |= ignore[:, :-1]  # mask to right
        change_mask[ignore] = False  # Don't mask what's already bad
        image.mask[change_mask] |= BADPIX_SUSPECT

        image.write_key('BFCFIL',
                        path.basename(bffile),
                        comment='Brighter/fatter correction file')

        ret_code = 0
        return ret_code
示例#9
0
    def __call__(cls, image, bpm_im, saturate, clear):
        """Create or update the mask plane of an image

        :Parameters:
            - `image`: the DESImage to operate upon.  Mask plane is created if absent
            - `bpm_im`: the DESBPMImage with the bad pixel mask. Skips BPM step if None
            - `saturate`: boolean flag indicating whether to set BADPIX_SATURATE flags
            - `clear`: if True, clear pre-existing mask.  If False, or new bits with old.

        """

        if image.mask is None:
            image.init_mask()
        elif clear:
            image.mask.fill(0)

        ret_code = 0
        if bpm_im is None and saturate is False:
            logger.warning('Null operation requested in make_mask')
            return ret_code

        #Flag saturated pixels first, if requested
        if saturate:
            # Check for header keyword of whether it's been done
            kw = 'DESSAT'
            if kw in image.header.keys() and not clear:
                logger.warning('Skipping saturation check (' + kw +
                               ' already set)')
            else:
                logger.info('Flagging saturated pixels')
                nsat = 0
                for amp in decaminfo.amps:
                    sec = section2slice(image['DATASEC' + amp])
                    sat = image['SATURAT' + amp]
                    satpix = image.data[sec] >= sat
                    image.mask[sec][satpix] |= BADPIX_SATURATE
                    nsat += np.count_nonzero(satpix)

                image.write_key(kw,
                                time.asctime(time.localtime()),
                                comment='Flag saturated pixels')
                image.write_key('NSATPIX',
                                nsat,
                                comment='Number of saturated pixels')

                logger.debug('Finished flagging saturated pixels')

        #Now fill in BPM
        if bpm_im is not None:
            # Check for header keyword of whether it's been done
            kw = 'DESBPM'
            if kw in image.header.keys() and not clear:
                logger.warning('Skipping BPM application (' + kw +
                               ' already set)')
            else:
                logger.info('Applying BPM')
                try:
                    items_must_match(image, bpm_im, 'CCDNUM')
                except:
                    return 1

                #====Temporary kluge until we get the new BPMS
                #Replace CORR with BIAS_COL
                #bitmask = BPMDEF_CORR
                #mark = (bpm_im.mask & bitmask) != 0
                #bpm_im.mask[mark] |= BPMDEF_BIAS_COL
                # Clear correctable bits from BPM if any are already set
                #bpm_im.mask -= (bpm_im.mask & BPMDEF_CORR)
                #====End kluge

                # Map the following BPM bits to BADPIX_BPM in the image mask
                bitmask = BPMDEF_FLAT_MIN | \
                    BPMDEF_FLAT_MAX | \
                    BPMDEF_FLAT_MASK | \
                    BPMDEF_BIAS_HOT | \
                    BPMDEF_BIAS_WARM | \
                    BPMDEF_BIAS_MASK | \
                    BPMDEF_BIAS_COL | \
                    BPMDEF_FUNKY_COL | \
                    BPMDEF_WACKY_PIX
                # ERICM Removed BPMDEF_CORR and added FUNKY_COL to the above list
                mark = (bpm_im.mask & bitmask) != 0
                image.mask[mark] |= BADPIX_BPM

                # Copy BPM edge pixels to image mask
                bitmask = BPMDEF_EDGE
                mark = (bpm_im.mask & bitmask) != 0
                image.mask[mark] |= BADPIX_EDGE

                # Copy bad amplifier bits to image mask
                bitmask = BPMDEF_BADAMP
                mark = (bpm_im.mask & bitmask) != 0
                image.mask[mark] |= BADPIX_BADAMP

                # Copy SUSPECT BPM bits to image mask
                bitmask = BPMDEF_SUSPECT
                mark = (bpm_im.mask & bitmask) != 0
                image.mask[mark] |= BADPIX_SUSPECT

                # Copy NEAREDGE BPM bits to image mask
                bitmask = BPMDEF_NEAREDGE
                mark = (bpm_im.mask & bitmask) != 0
                image.mask[mark] |= BADPIX_NEAREDGE

                # Copy TAPEBUMP BPM bits to image mask
                bitmask = BPMDEF_TAPEBUMP
                mark = (bpm_im.mask & bitmask) != 0
                image.mask[mark] |= BADPIX_TAPEBUMP

                # Mark correctable pixels.
                # Pixels flagged as BPMDEF_BIAS_COL and BPMDEF_FUNKY_COL may be correctable.
                # We flag them in the image as bad (BADPIX_BPM), but - if fix_columns is run,
                # the BADPIX_BPM flag will be cleared and the BADPIX_FIX flag will be set
                # For each column find the number of pixels flagged as BIAS_HOT and BIAS_COL
                N_BIAS_HOT = np.sum((bpm_im.mask & BPMDEF_BIAS_HOT) > 0,
                                    axis=0)
                N_BIAS_COL = np.sum((bpm_im.mask & BPMDEF_BIAS_COL) > 0,
                                    axis=0)
                maskwidth = bpm_im.mask.shape[1]
                # First do columns with N_BIAS_COL set for 1 or more pixels
                biascols = np.arange(maskwidth)[(N_BIAS_COL > 0)]
                for icol in biascols:
                    #Clear FUNKY_COL bit if set for all pixels in this column
                    #The reason for clearing the bit is that the FUNKY_COL detection is
                    #sensitive to hot bias pixels and may flag those columns by "mistake"
                    #First clear BAD BPM bit if set because of funky column
                    image.mask[:, icol][bpm_im.mask[:, icol] ==
                                        BPMDEF_FUNKY_COL] &= ~BADPIX_BPM
                    bpm_im.mask[:, icol] -= (bpm_im.mask[:, icol]
                                             & BPMDEF_FUNKY_COL)
                    #Correctable columns have exactly 1 BIAS_HOT pixel
                    if N_BIAS_HOT[icol] == 1:
                        #Correctable pixels have BIAS_COL bit set
                        bpm_im.mask[:, icol][(
                            bpm_im.mask[:, icol]
                            & BPMDEF_BIAS_COL) > 0] |= BPMDEF_CORR
                        logger.info('Column ' + str(icol) +
                                    ' has 1 hot pixel and is correctable.')
                    else:
                        logger.info('Column ' + str(icol) + ' has ' +
                                    str(N_BIAS_HOT[icol]) +
                                    ' hot pixels and is NOT correctable.')

                #Now do columns with FUNKY_COL set.  Note that the FUNKY_COL bits have been cleared above
                #for hot bias columns
                N_FUNKY_COL = np.sum((bpm_im.mask & BPMDEF_FUNKY_COL) > 0,
                                     axis=0)
                funkycols = np.arange(maskwidth)[(N_FUNKY_COL > 0)]
                for icol in funkycols:
                    #Correctable pixels have FUNKY_COL bit set
                    bpm_im.mask[:,
                                icol][(bpm_im.mask[:, icol]
                                       & BPMDEF_FUNKY_COL) > 0] |= BPMDEF_CORR
                    logger.info('Column ' + str(icol) +
                                ' is funky and correctable.')

                image[kw] = time.asctime(time.localtime())
                image.write_key(kw,
                                time.asctime(time.localtime()),
                                comment='Construct mask from BPM')
                if bpm_im.sourcefile is None:
                    image.write_key('BPMFIL',
                                    'UNKNOWN',
                                    comment='BPM file used to build mask')
                else:
                    image.write_key('BPMFIL',
                                    path.basename(bpm_im.sourcefile),
                                    comment='BPM file used to build mask')

                logger.debug('Finished applying BPM')

        return ret_code