def __init__(self):
# allocate memory for the gvalue which will be freed on GC
self.pointer = ffi.new('GValue *')
# logger.debug('GValue.__init__: pointer = %s', self.pointer)
# and tag it to be unset on GC as well
self.gvalue = ffi.gc(self.pointer, gobject_lib.g_value_unset)
def write_to_memory(self):
"""Write the image to a large memory array.
A large area of memory is allocated, the image is rendered to that
memory array, and the array is returned as a buffer.
For example, if you have a 2x2 uchar image containing the bytes 1, 2,
3, 4, read left-to-right, top-to-bottom, then::
buf = image.write_to_memory()
will return a four byte buffer containing the values 1, 2, 3, 4.
Returns:
buffer
Raises:
:class:`.Error`
"""
psize = ffi.new('size_t *')
pointer = vips_lib.vips_image_write_to_memory(self.pointer, psize)
if pointer == ffi.NULL:
raise Error('unable to write to memory')
pointer = ffi.gc(pointer, glib_lib.g_free)
return ffi.buffer(pointer, psize[0])
def _get_pspec(self, name):
# logger.debug('VipsObject.get_typeof: self = %s, name = %s',
# str(self), name)
pspec = ffi.new('GParamSpec **')
argument_class = ffi.new('VipsArgumentClass **')
argument_instance = ffi.new('VipsArgumentInstance **')
result = vips_lib.vips_object_get_argument(self.vobject,
_to_bytes(name), pspec,
argument_class,
argument_instance)
if result != 0:
return None
return pspec[0]
def new_from_array(array, scale=1.0, offset=0.0):
"""Create an image from a 1D or 2D array.
A new one-band image with :class:`BandFormat` ``'double'`` pixels is
created from the array. These image are useful with the libvips
convolution operator :meth:`Image.conv`.
Args:
array (list[list[float]]): Create the image from these values.
1D arrays become a single row of pixels.
scale (float): Default to 1.0. What to divide each pixel by after
convolution. Useful for integer convolution masks.
offset (float): Default to 0.0. What to subtract from each pixel
after convolution. Useful for integer convolution masks.
Returns:
A new :class:`Image`.
Raises:
:class:`.Error`
"""
if not _is_2D(array):
array = [array]
height = len(array)
width = len(array[0])
n = width * height
a = ffi.new('double[]', n)
for y in range(0, height):
for x in range(0, width):
a[x + y * width] = array[y][x]
vi = vips_lib.vips_image_new_matrix_from_array(width, height, a, n)
if vi == ffi.NULL:
raise Error('unable to make image from matrix')
image = pyvips.Image(vi)
image.set_type(GValue.gdouble_type, 'scale', scale)
image.set_type(GValue.gdouble_type, 'offset', offset)
return image
def fetch(self, x, y, w, h):
"""Fill a region with pixel data.
Pixels are filled with data!
Returns:
Pixel data.
Raises:
:class:`.Error`
"""
if not at_least_libvips(8, 8):
raise Error('libvips too old')
psize = ffi.new('size_t *')
pointer = vips_lib.vips_region_fetch(self.pointer, x, y, w, h, psize)
if pointer == ffi.NULL:
raise Error('unable to fetch from region')
pointer = ffi.gc(pointer, glib_lib.g_free)
return ffi.buffer(pointer, psize[0])
def __init__(self, operation_name):
op = Operation.new_from_name(operation_name)
self.description = op.get_description()
self.flags = vips_lib.vips_operation_get_flags(op.pointer)
# build a list of constructor arg [name, flags] pairs in arg order
arguments = []
def add_args(name, flags):
if (flags & _CONSTRUCT) != 0:
# libvips uses '-' to separate parts of arg names, but we
# need '_' for Python
name = name.replace('-', '_')
arguments.append([name, flags])
if at_least_libvips(8, 7):
p_names = ffi.new('char**[1]')
p_flags = ffi.new('int*[1]')
p_n_args = ffi.new('int[1]')
result = vips_lib.vips_object_get_args(op.vobject, p_names,
p_flags, p_n_args)
if result != 0:
raise Error('unable to get arguments from operation')
p_names = p_names[0]
p_flags = p_flags[0]
n_args = p_n_args[0]
for i in range(0, n_args):
add_args(_to_string(p_names[i]), p_flags[i])
else:
def add_construct(self, pspec, argument_class, argument_instance,
a, b):
add_args(_to_string(pspec.name), argument_class.flags)
return ffi.NULL
cb = ffi.callback('VipsArgumentMapFn', add_construct)
vips_lib.vips_argument_map(op.vobject, cb, ffi.NULL, ffi.NULL)
# logger.debug('arguments = %s', self.arguments)
# build a hash from arg name to detailed arg information
self.details = {}
for name, flags in arguments:
self.details[name] = {
"name": name,
"flags": flags,
"blurb": op.get_blurb(name),
"type": op.get_typeof(name)
}
# lists of arg names by category
self.required_input = []
self.optional_input = []
self.required_output = []
self.optional_output = []
for name, flags in arguments:
if ((flags & _INPUT) != 0 and (flags & _REQUIRED) != 0
and (flags & _DEPRECATED) == 0):
self.required_input.append(name)
# required inputs which we MODIFY are also required outputs
if (flags & _MODIFY) != 0:
self.required_output.append(name)
if ((flags & _OUTPUT) != 0 and (flags & _REQUIRED) != 0
and (flags & _DEPRECATED) == 0):
self.required_output.append(name)
# we let deprecated optional args through, but warn about them
# if they get used, see below
if ((flags & _INPUT) != 0 and (flags & _REQUIRED) == 0):
self.optional_input.append(name)
if ((flags & _OUTPUT) != 0 and (flags & _REQUIRED) == 0):
self.optional_output.append(name)
# find the first required input image arg, if any ... that will be self
self.member_x = None
for name in self.required_input:
details = self.details[name]
if details['type'] == GValue.image_type:
self.member_x = name
break
# method args are required args, but without the image they are a
# method on
if self.member_x is not None:
self.method_args = list(self.required_input)
self.method_args.remove(self.member_x)
else:
self.method_args = self.required_input
def get(self):
"""Get the contents of a GValue.
The contents of the GValue are read out as a Python type.
"""
# logger.debug('GValue.get: self = %s', self)
gtype = self.gvalue.g_type
fundamental = gobject_lib.g_type_fundamental(gtype)
result = None
if gtype == GValue.gbool_type:
result = bool(gobject_lib.g_value_get_boolean(self.gvalue))
elif gtype == GValue.gint_type:
result = gobject_lib.g_value_get_int(self.gvalue)
elif gtype == GValue.gdouble_type:
result = gobject_lib.g_value_get_double(self.gvalue)
elif fundamental == GValue.genum_type:
return GValue.from_enum(gtype,
gobject_lib.g_value_get_enum(self.gvalue))
elif fundamental == GValue.gflags_type:
result = gobject_lib.g_value_get_flags(self.gvalue)
elif gtype == GValue.gstr_type:
pointer = gobject_lib.g_value_get_string(self.gvalue)
if pointer != ffi.NULL:
result = _to_string(pointer)
elif gtype == GValue.refstr_type:
psize = ffi.new('size_t *')
pointer = vips_lib.vips_value_get_ref_string(self.gvalue, psize)
# psize[0] will be number of bytes in string, but just assume it's
# NULL-terminated
result = _to_string(pointer)
elif gtype == GValue.image_type:
# g_value_get_object() will not add a ref ... that is
# held by the gvalue
go = gobject_lib.g_value_get_object(self.gvalue)
vi = ffi.cast('VipsImage *', go)
# we want a ref that will last with the life of the vimage:
# this ref is matched by the unref that's attached to finalize
# by Image()
gobject_lib.g_object_ref(go)
result = pyvips.Image(vi)
elif gtype == GValue.array_int_type:
pint = ffi.new('int *')
array = vips_lib.vips_value_get_array_int(self.gvalue, pint)
result = []
for i in range(0, pint[0]):
result.append(array[i])
elif gtype == GValue.array_double_type:
pint = ffi.new('int *')
array = vips_lib.vips_value_get_array_double(self.gvalue, pint)
result = []
for i in range(0, pint[0]):
result.append(array[i])
elif gtype == GValue.array_image_type:
pint = ffi.new('int *')
array = vips_lib.vips_value_get_array_image(self.gvalue, pint)
result = []
for i in range(0, pint[0]):
vi = array[i]
gobject_lib.g_object_ref(vi)
image = pyvips.Image(vi)
result.append(image)
elif gtype == GValue.blob_type:
psize = ffi.new('size_t *')
array = vips_lib.vips_value_get_blob(self.gvalue, psize)
buf = ffi.cast('char*', array)
result = ffi.unpack(buf, psize[0])
else:
raise Error('unsupported gtype for get {0}'.format(
type_name(gtype)))
return result
def set(self, value):
"""Set a GValue.
The value is converted to the type of the GValue, if possible, and
assigned.
"""
# logger.debug('GValue.set: value = %s', value)
gtype = self.gvalue.g_type
fundamental = gobject_lib.g_type_fundamental(gtype)
if gtype == GValue.gbool_type:
gobject_lib.g_value_set_boolean(self.gvalue, value)
elif gtype == GValue.gint_type:
gobject_lib.g_value_set_int(self.gvalue, int(value))
elif gtype == GValue.gdouble_type:
gobject_lib.g_value_set_double(self.gvalue, value)
elif fundamental == GValue.genum_type:
gobject_lib.g_value_set_enum(self.gvalue,
GValue.to_enum(gtype, value))
elif fundamental == GValue.gflags_type:
gobject_lib.g_value_set_flags(self.gvalue, value)
elif gtype == GValue.gstr_type:
gobject_lib.g_value_set_string(self.gvalue, _to_bytes(value))
elif gtype == GValue.refstr_type:
vips_lib.vips_value_set_ref_string(self.gvalue, _to_bytes(value))
elif fundamental == GValue.gobject_type:
gobject_lib.g_value_set_object(self.gvalue, value.pointer)
elif gtype == GValue.array_int_type:
if isinstance(value, numbers.Number):
value = [value]
array = ffi.new('int[]', value)
vips_lib.vips_value_set_array_int(self.gvalue, array, len(value))
elif gtype == GValue.array_double_type:
if isinstance(value, numbers.Number):
value = [value]
array = ffi.new('double[]', value)
vips_lib.vips_value_set_array_double(self.gvalue, array,
len(value))
elif gtype == GValue.array_image_type:
if isinstance(value, pyvips.Image):
value = [value]
vips_lib.vips_value_set_array_image(self.gvalue, len(value))
array = vips_lib.vips_value_get_array_image(self.gvalue, ffi.NULL)
for i, image in enumerate(value):
gobject_lib.g_object_ref(image.pointer)
array[i] = image.pointer
elif gtype == GValue.blob_type:
# we need to set the blob to a copy of the string that vips_lib
# can own
memory = glib_lib.g_malloc(len(value))
ffi.memmove(memory, value, len(value))
# this is horrible!
#
# * in API mode, we must have 8.6+ and use set_blob_free to
# attach the metadata to avoid leaks
# * pre-8.6, we just pass a NULL free pointer and live with the
# leak
#
# this is because in API mode you can't pass a builtin (what
# vips_lib.g_free() becomes) as a parameter to ffi.callback(), and
# vips_value_set_blob() needs a callback for arg 2
#
# additionally, you can't make a py def which calls g_free() and
# then use the py def in the callback, since libvips will trigger
# these functions during cleanup, and py will have shut down by
# then and you'll get a segv
if at_least_libvips(8, 6):
vips_lib.vips_value_set_blob_free(self.gvalue, memory,
len(value))
else:
if pyvips.API_mode:
vips_lib.vips_value_set_blob(self.gvalue, ffi.NULL, memory,
len(value))
else:
vips_lib.vips_value_set_blob(self.gvalue, glib_lib.g_free,
memory, len(value))
else:
raise Error(
'unsupported gtype for set {0}, fundamental {1}'.format(
type_name(gtype), type_name(fundamental)))
def set(self, value):
"""Set a GValue.
The value is converted to the type of the GValue, if possible, and
assigned.
"""
# logger.debug('GValue.set: value = %s', value)
gtype = self.gvalue.gtype
fundamental = gobject_lib.g_type_fundamental(gtype)
if gtype == GValue.gbool_type:
gobject_lib.g_value_set_boolean(self.gvalue, value)
elif gtype == GValue.gint_type:
gobject_lib.g_value_set_int(self.gvalue, int(value))
elif gtype == GValue.gdouble_type:
gobject_lib.g_value_set_double(self.gvalue, value)
elif fundamental == GValue.genum_type:
gobject_lib.g_value_set_enum(self.gvalue,
GValue.to_enum(gtype, value))
elif fundamental == GValue.gflags_type:
gobject_lib.g_value_set_flags(self.gvalue, value)
elif gtype == GValue.gstr_type or gtype == GValue.refstr_type:
gobject_lib.g_value_set_string(self.gvalue, _to_bytes(value))
elif fundamental == GValue.gobject_type:
gobject_lib.g_value_set_object(self.gvalue, value.pointer)
elif gtype == GValue.array_int_type:
if isinstance(value, numbers.Number):
value = [value]
array = ffi.new('int[]', value)
vips_lib.vips_value_set_array_int(self.gvalue, array, len(value))
elif gtype == GValue.array_double_type:
if isinstance(value, numbers.Number):
value = [value]
array = ffi.new('double[]', value)
vips_lib.vips_value_set_array_double(self.gvalue, array,
len(value))
elif gtype == GValue.array_image_type:
if isinstance(value, pyvips.Image):
value = [value]
vips_lib.vips_value_set_array_image(self.gvalue, len(value))
array = vips_lib.vips_value_get_array_image(self.gvalue, ffi.NULL)
for i, image in enumerate(value):
gobject_lib.g_object_ref(image.pointer)
array[i] = image.pointer
elif gtype == GValue.blob_type:
# we need to set the blob to a copy of the string that vips_lib
# can own
memory = glib_lib.g_malloc(len(value))
ffi.memmove(memory, value, len(value))
vips_lib.vips_value_set_blob(self.gvalue, glib_lib.g_free, memory,
len(value))
else:
raise Error(
'unsupported gtype for set {0}, fundamental {1}'.format(
type_name(gtype), type_name(fundamental)))
