From b75426792312ab33c434180f1a493dfa19a3ff51 Mon Sep 17 00:00:00 2001 From: jevans Date: Fri, 17 Oct 2014 22:51:14 -0400 Subject: [PATCH] initial refactor --- glymur/jp2k.py | 271 +++++++++++++++++++++++-------------------------- 1 file changed, 128 insertions(+), 143 deletions(-) diff --git a/glymur/jp2k.py b/glymur/jp2k.py index d460ea6..bce0991 100644 --- a/glymur/jp2k.py +++ b/glymur/jp2k.py @@ -45,6 +45,11 @@ JP2_IDS = ['colr', 'cdef', 'cmap', 'jp2c', 'ftyp', 'ihdr', 'jp2h', 'jP ', 'uuid'] JPX_IDS = ['asoc', 'nlst'] +_COLORSPACE_MAP = {'rgb': opj2.CLRSPC_SRGB, + 'gray': opj2.CLRSPC_GRAY, + 'grey': opj2.CLRSPC_GRAY, + 'ycc': opj2.CLRSPC_YCC} + class Jp2k(Jp2kBox): """JPEG 2000 file. @@ -74,6 +79,7 @@ class Jp2k(Jp2kBox): self.mode = mode self.box = [] self._codec_format = None + self._colorspace = None # Parse the file for JP2/JPX contents only if we are reading it. if mode == 'rb': @@ -338,27 +344,18 @@ class Jp2k(Jp2kBox): return cparams - def _process_write_inputs(self, img_array, colorspace=None, **kwargs): + def _process_write_inputs(self, img_array, **kwargs): """Directs processing of write method arguments. - It's somewhat awkward to process all the kwargs arguments at once. - The "colorspace" is not a parameter that gets processed into the - compression parameters structure, and it unfortunately must be handled - in the middle of the compression parameter processing. - Parameters ---------- img_array : ndarray Image data to be written to file. - colorspace : str, optional - Either 'rgb' or 'gray'. Returns ------- cparams : CompressionParametersType(ctypes.Structure) Corresponds to cparameters_t type in openjp2 headers. - colorspace : int - Either CLRSPC_SRGB or CLRSPC_GRAY """ if (('cinema2k' in kwargs or 'cinema4k' in kwargs) and (len(set(kwargs)) > 1)): @@ -370,13 +367,11 @@ class Jp2k(Jp2kBox): raise IOError(msg) cparams = self._populate_cparams(**kwargs) - _validate_compression_params(img_array, cparams) - - colorspace = _unpack_colorspace(colorspace, img_array, cparams) + self._validate_compression_params(img_array, cparams, **kwargs) try: mct = kwargs['mct'] - if mct and colorspace == opj2.CLRSPC_GRAY: + if mct and self._colorspace == opj2.CLRSPC_GRAY: # Cannot check for this in the validate routine, as we need # to know what the target colorspace has been determined to be. msg = "Cannot specify usage of the multi component transform " @@ -386,12 +381,12 @@ class Jp2k(Jp2kBox): except KeyError: # If the multi component transform was not specified, we infer # that it should be used if the color space is RGB. - if colorspace == opj2.CLRSPC_SRGB: + if self._colorspace == opj2.CLRSPC_SRGB: cparams.tcp_mct = 1 else: cparams.tcp_mct = 0 - return cparams, colorspace + return cparams def write(self, img_array, verbose=False, **kwargs): """Write image data to a JP2/JPX/J2k file. Intended usage of the @@ -466,21 +461,23 @@ class Jp2k(Jp2kBox): glymur.LibraryNotFoundError If glymur is unable to load the openjp2 library. """ - if opj2.OPENJP2 is not None: - self._write_openjp2(img_array, verbose=verbose, **kwargs) - elif opj.OPENJPEG is not None: - self._write_openjpeg(img_array, verbose=verbose, **kwargs) - else: + if opj2.OPENJP2 is None and opj.OPENJPEG is None: raise LibraryNotFoundError("You must have at least version 1.5 of " "OpenJPEG before using this " "functionality.") - def _write_openjpeg(self, img_array, verbose=False, **kwargs): + self._determine_colorspace(img_array, **kwargs) + cparams = self._process_write_inputs(img_array, **kwargs) + + if opj2.OPENJP2 is not None: + self._write_openjp2(img_array, cparams, verbose=verbose) + else: + self._write_openjpeg(img_array, cparams, verbose=verbose) + + def _write_openjpeg(self, img_array, cparams, verbose=False): """ Write JPEG 2000 file using OpenJPEG 1.5 interface. """ - cparams, colorspace = self._process_write_inputs(img_array, **kwargs) - if img_array.ndim == 2: # Force the image to be 3D. Just makes things easier later on. img_array = img_array.reshape(img_array.shape[0], @@ -490,7 +487,7 @@ class Jp2k(Jp2kBox): comptparms = _populate_comptparms(img_array, cparams) with ExitStack() as stack: - image = opj.image_create(comptparms, colorspace) + image = opj.image_create(comptparms, self._colorspace) stack.callback(opj.image_destroy, image) numrows, numcols, numlayers = img_array.shape @@ -542,13 +539,114 @@ class Jp2k(Jp2kBox): self.parse() + def _validate_compression_params(self, img_array, cparams, **kwargs): + """Check that the compression parameters are valid. - def _write_openjp2(self, img_array, verbose=False, **kwargs): + Parameters + ---------- + img_array : ndarray + Image data to be written to file. + cparams : CompressionParametersType(ctypes.Structure) + Corresponds to cparameters_t type in openjp2 headers. """ - Write JPEG 2000 file using OpenJPEG 2.0 interface. - """ - cparams, colorspace = self._process_write_inputs(img_array, **kwargs) + # Cannot specify a colorspace with J2K. + if cparams.codec_fmt == opj2.CODEC_J2K and 'colorspace' in kwargs: + msg = 'Do not specify a colorspace when writing a raw ' + msg += 'codestream.' + raise IOError(msg) + # Code block size + code_block_specified = False + if cparams.cblockw_init != 0 and cparams.cblockh_init != 0: + # These fields ARE zero if uninitialized. + width = cparams.cblockw_init + height = cparams.cblockh_init + code_block_specified = True + if height * width > 4096 or height < 4 or width < 4: + msg = "Code block area cannot exceed 4096. " + msg += "Code block height and width must be larger than 4." + raise IOError(msg) + if ((math.log(height, 2) != math.floor(math.log(height, 2)) or + math.log(width, 2) != math.floor(math.log(width, 2)))): + msg = "Bad code block size ({0}, {1}), " + msg += "must be powers of 2." + raise IOError(msg.format(height, width)) + + # Precinct size + if cparams.res_spec != 0: + # precinct size was not specified if this field is zero. + for j in range(cparams.res_spec): + prch = cparams.prch_init[j] + prcw = cparams.prcw_init[j] + if j == 0 and code_block_specified: + height, width = cparams.cblockh_init, cparams.cblockw_init + if height * 2 > prch or width * 2 > prcw: + msg = "Highest Resolution precinct size must be at " + msg += "least twice that of the code block dimensions." + raise IOError(msg) + if ((math.log(prch, 2) != math.floor(math.log(prch, 2)) or + math.log(prcw, 2) != math.floor(math.log(prcw, 2)))): + msg = "Bad precinct sizes ({0}, {1}), " + msg += "must be powers of 2." + raise IOError(msg.format(prch, prcw)) + + # What would the point of 1D images be? + if img_array.ndim == 1 or img_array.ndim > 3: + msg = "{0}D imagery is not allowed.".format(img_array.ndim) + raise IOError(msg) + + if re.match("2.0.0", version.openjpeg_version) is not None: + if (((img_array.ndim != 2) and + (img_array.shape[2] != 1 and img_array.shape[2] != 3))): + msg = "Writing images is restricted to single-channel " + msg += "greyscale images or three-channel RGB images when " + msg += "the OpenJPEG library version is the official 2.0.0 " + msg += "release." + raise IOError(msg) + + if img_array.dtype != np.uint8 and img_array.dtype != np.uint16: + msg = "Only uint8 and uint16 images are currently supported." + raise RuntimeError(msg) + + def _determine_colorspace(self, img_array, colorspace=None, **kwargs): + """Determine the colorspace from the supplied inputs. + + Parameters + ---------- + img_array : ndarray + Image data to be written to file. + colorspace : str, optional + Either 'rgb' or 'gray'. + """ + if colorspace is None: + # Must infer the colorspace from the image dimensions. + if img_array.ndim < 3: + # A single channel image is grayscale. + self._colorspace = opj2.CLRSPC_GRAY + elif img_array.shape[2] == 1 or img_array.shape[2] == 2: + # A single channel image or an image with two channels is going + # to be greyscale. + self._colorspace = opj2.CLRSPC_GRAY + else: + # Anything else must be RGB, right? + self._colorspace = opj2.CLRSPC_SRGB + else: + if colorspace.lower() not in ('rgb', 'grey', 'gray'): + msg = 'Invalid colorspace "{0}"'.format(colorspace) + raise IOError(msg) + elif colorspace.lower() == 'rgb' and img_array.shape[2] < 3: + msg = 'RGB colorspace requires at least 3 components.' + raise IOError(msg) + + # Turn the colorspace from a string to the enumerated value that + # the library expects. + self._colorspace = _COLORSPACE_MAP[colorspace.lower()] + + + def _write_openjp2(self, img_array, cparams, verbose=False): + """ + Write JPEG 2000 file using OpenJPEG 2.x interface. + """ if img_array.ndim == 2: # Force the image to be 3D. Just makes things easier later on. numrows, numcols = img_array.shape @@ -557,7 +655,7 @@ class Jp2k(Jp2kBox): comptparms = _populate_comptparms(img_array, cparams) with ExitStack() as stack: - image = opj2.image_create(comptparms, colorspace) + image = opj2.image_create(comptparms, self._colorspace) stack.callback(opj2.image_destroy, image) _populate_image_struct(cparams, image, img_array) @@ -1674,50 +1772,6 @@ def extract_image_bands(image): return data -def _unpack_colorspace(colorspace, img_array, cparams): - """Determine the colorspace from the supplied inputs. - - Parameters - ---------- - colorspace : int - Either CLRSPC_SRGB or CLRSPC_GRAY - img_array : ndarray - Image data to be written to file. - cparams : CompressionParametersType(ctypes.Structure) - Corresponds to cparameters_t type in openjp2 headers. - """ - if colorspace is None: - # Must infer the colorspace from the image dimensions. - if img_array.ndim < 3: - # A single channel image is grayscale. - colorspace = opj2.CLRSPC_GRAY - elif img_array.shape[2] == 1 or img_array.shape[2] == 2: - # A single channel image or an image with two channels is going - # to be greyscale. - colorspace = opj2.CLRSPC_GRAY - else: - # Anything else must be RGB, right? - colorspace = opj2.CLRSPC_SRGB - else: - # Supplied a string colorspace, so we must validate it. - if cparams.codec_fmt == opj2.CODEC_J2K: - msg = 'Do not specify a colorspace when writing a raw ' - msg += 'codestream.' - raise IOError(msg) - if colorspace.lower() not in ('rgb', 'grey', 'gray'): - msg = 'Invalid colorspace "{0}"'.format(colorspace) - raise IOError(msg) - elif colorspace.lower() == 'rgb' and img_array.shape[2] < 3: - msg = 'RGB colorspace requires at least 3 components.' - raise IOError(msg) - - # Turn the colorspace from a string to the enumerated value that - # the library expects. - colorspace = _COLORSPACE_MAP[colorspace.lower()] - - return colorspace - - def _populate_comptparms(img_array, cparams): """Instantiate and populate comptparms structure. @@ -1805,75 +1859,6 @@ def _populate_image_struct(cparams, image, imgdata): return image -def _validate_compression_params(img_array, cparams): - """Check that the compression parameters are valid. - - Parameters - ---------- - img_array : ndarray - Image data to be written to file. - cparams : CompressionParametersType(ctypes.Structure) - Corresponds to cparameters_t type in openjp2 headers. - """ - - # Code block size - code_block_specified = False - if cparams.cblockw_init != 0 and cparams.cblockh_init != 0: - # These fields ARE zero if uninitialized. - width = cparams.cblockw_init - height = cparams.cblockh_init - code_block_specified = True - if height * width > 4096 or height < 4 or width < 4: - msg = "Code block area cannot exceed 4096. " - msg += "Code block height and width must be larger than 4." - raise IOError(msg) - if ((math.log(height, 2) != math.floor(math.log(height, 2)) or - math.log(width, 2) != math.floor(math.log(width, 2)))): - msg = "Bad code block size ({0}, {1}), " - msg += "must be powers of 2." - raise IOError(msg.format(height, width)) - - # Precinct size - if cparams.res_spec != 0: - # precinct size was not specified if this field is zero. - for j in range(cparams.res_spec): - prch = cparams.prch_init[j] - prcw = cparams.prcw_init[j] - if j == 0 and code_block_specified: - height, width = cparams.cblockh_init, cparams.cblockw_init - if height * 2 > prch or width * 2 > prcw: - msg = "Highest Resolution precinct size must be at " - msg += "least twice that of the code block dimensions." - raise IOError(msg) - if ((math.log(prch, 2) != math.floor(math.log(prch, 2)) or - math.log(prcw, 2) != math.floor(math.log(prcw, 2)))): - msg = "Bad precinct sizes ({0}, {1}), " - msg += "must be powers of 2." - raise IOError(msg.format(prch, prcw)) - - # What would the point of 1D images be? - if img_array.ndim == 1 or img_array.ndim > 3: - msg = "{0}D imagery is not allowed.".format(img_array.ndim) - raise IOError(msg) - - if re.match("2.0.0", version.openjpeg_version) is not None: - if (((img_array.ndim != 2) and - (img_array.shape[2] != 1 and img_array.shape[2] != 3))): - msg = "Writing images is restricted to single-channel " - msg += "greyscale images or three-channel RGB images when " - msg += "the OpenJPEG library version is the official 2.0.0 " - msg += "release." - raise IOError(msg) - - if img_array.dtype != np.uint8 and img_array.dtype != np.uint16: - msg = "Only uint8 and uint16 images are currently supported." - raise RuntimeError(msg) - -_COLORSPACE_MAP = {'rgb': opj2.CLRSPC_SRGB, - 'gray': opj2.CLRSPC_GRAY, - 'grey': opj2.CLRSPC_GRAY, - 'ycc': opj2.CLRSPC_YCC} - # Setup the default callback handlers. See the callback functions subsection # in the ctypes section of the Python documentation for a solid explanation of # what's going on here.