# Encoded API

This feature is only possible since PyTango 7.1.4

class tango.EncodedAttribute(*args, **kwargs)
  decode_gray16(da, extract_as=None)

    Decode a 16 bits grayscale image (GRAY16) and returns a 16 bits gray scale image.

    > param da:

    >   `DeviceAttribute` that contains the image

    > type da:

    >   `DeviceAttribute`

    > param extract_as:

    >   defaults to ExtractAs.Numpy

    > type extract_as:

    >   ExtractAs

    > return:

    >   the decoded data

    > - In case String string is choosen as extract method, a tuple is returned:

    >     width<int>, height<int>, buffer<str>

    > - In case Numpy is choosen as extract method, a `numpy.ndarray` is returned with ndim=2, shape=(height, width) and dtype=numpy.uint16.

    > - In case Tuple or List are choosen, a tuple<tuple<int>> or list<list<int>> is returned.

    Warning

    The PyTango calls that return a `DeviceAttribute` (like `DeviceProxy.read_attribute()` or `DeviceProxy.command_inout()`) automatically extract the contents by default. This method requires that the given `DeviceAttribute` is obtained from a call which DOESN’T extract the contents. Example:

        dev = tango.DeviceProxy("a/b/c")
        da = dev.read_attribute("my_attr", extract_as=tango.ExtractAs.Nothing)
        enc = tango.EncodedAttribute()
        data = enc.decode_gray16(da)

  decode_gray8(da, extract_as=None)

    Decode a 8 bits grayscale image (JPEG_GRAY8 or GRAY8) and returns a 8 bits gray scale image.

    > param da:

    >   `DeviceAttribute` that contains the image

    > type da:

    >   `DeviceAttribute`

    > param extract_as:

    >   defaults to ExtractAs.Numpy

    > type extract_as:

    >   ExtractAs

    > return:

    >   the decoded data

    > - In case String string is choosen as extract method, a tuple is returned:

    >     width<int>, height<int>, buffer<str>

    > - In case Numpy is choosen as extract method, a `numpy.ndarray` is returned with ndim=2, shape=(height, width) and dtype=numpy.uint8.

    > - In case Tuple or List are choosen, a tuple<tuple<int>> or list<list<int>> is returned.

    Warning

    The PyTango calls that return a `DeviceAttribute` (like `DeviceProxy.read_attribute()` or `DeviceProxy.command_inout()`) automatically extract the contents by default. This method requires that the given `DeviceAttribute` is obtained from a call which DOESN’T extract the contents. Example:

        dev = tango.DeviceProxy("a/b/c")
        da = dev.read_attribute("my_attr", extract_as=tango.ExtractAs.Nothing)
        enc = tango.EncodedAttribute()
        data = enc.decode_gray8(da)

  decode_rgb32(da, extract_as=None)

    Decode a color image (JPEG_RGB or RGB24) and returns a 32 bits RGB image.

    > param da:

    >   `DeviceAttribute` that contains the image

    > type da:

    >   `DeviceAttribute`

    > param extract_as:

    >   defaults to ExtractAs.Numpy

    > type extract_as:

    >   ExtractAs

    > return:

    >   the decoded data

    > - In case String string is choosen as extract method, a tuple is returned:

    >     width<int>, height<int>, buffer<str>

    > - In case Numpy is choosen as extract method, a `numpy.ndarray` is returned with ndim=2, shape=(height, width) and dtype=numpy.uint32.

    > - In case Tuple or List are choosen, a tuple<tuple<int>> or list<list<int>> is returned.

    Warning

    The PyTango calls that return a `DeviceAttribute` (like `DeviceProxy.read_attribute()` or `DeviceProxy.command_inout()`) automatically extract the contents by default. This method requires that the given `DeviceAttribute` is obtained from a call which DOESN’T extract the contents. Example:

        dev = tango.DeviceProxy("a/b/c")
        da = dev.read_attribute("my_attr", extract_as=tango.ExtractAs.Nothing)
        enc = tango.EncodedAttribute()
        data = enc.decode_rgb32(da)

  encode_gray16(gray16, width=0, height=0)

    Encode a 16 bit grayscale image (no compression)

    > param gray16:

    >   an object containning image information

    > type gray16:

    >   `str` or `buffer` or `numpy.ndarray` or seq< seq<element> >

    > param width:

    >   image width. MUST be given if gray16 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type width:

    >   `int`

    > param height:

    >   image height. MUST be given if gray16 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type height:

    >   `int`

    Note

    When `numpy.ndarray` is given:

    > - gray16 MUST be CONTIGUOUS, ALIGNED

    > - if gray16.ndims != 2, width and height MUST be given and gray16.nbytes/2 MUST match width*height

    > - if gray16.ndims == 2, gray16.itemsize MUST be 2 (typically, gray16.dtype is one of numpy.dtype.int16, numpy.dtype.uint16, numpy.dtype.short or numpy.dtype.ushort)

    Example:

      :

          def read_myattr(self):
              enc = tango.EncodedAttribute()
              data = numpy.arange(100, dtype=numpy.int16)
              data = numpy.array((data,data,data))
              enc.encode_gray16(data)
              return enc

  encode_gray8(gray8, width=0, height=0)

    Encode a 8 bit grayscale image (no compression)

    > param gray8:

    >   an object containning image information

    > type gray8:

    >   `str` or `numpy.ndarray` or seq< seq<element> >

    > param width:

    >   image width. MUST be given if gray8 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type width:

    >   `int`

    > param height:

    >   image height. MUST be given if gray8 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type height:

    >   `int`

    Note

    When `numpy.ndarray` is given:

    > - gray8 MUST be CONTIGUOUS, ALIGNED

    > - if gray8.ndims != 2, width and height MUST be given and gray8.nbytes MUST match width*height

    > - if gray8.ndims == 2, gray8.itemsize MUST be 1 (typically, gray8.dtype is one of numpy.dtype.byte, numpy.dtype.ubyte, numpy.dtype.int8 or numpy.dtype.uint8)

    Example:

      :

          def read_myattr(self):
              enc = tango.EncodedAttribute()
              data = numpy.arange(100, dtype=numpy.byte)
              data = numpy.array((data,data,data))
              enc.encode_gray8(data)
              return enc

  encode_jpeg_gray8(gray8, width=0, height=0, quality=100.0)

    Encode a 8 bit grayscale image as JPEG format

    > param gray8:

    >   an object containning image information

    > type gray8:

    >   `str` or `numpy.ndarray` or seq< seq<element> >

    > param width:

    >   image width. MUST be given if gray8 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type width:

    >   `int`

    > param height:

    >   image height. MUST be given if gray8 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type height:

    >   `int`

    > param quality:

    >   Quality of JPEG (0=poor quality 100=max quality) (default is 100.0)

    > type quality:

    >   `float`

    Note

    When `numpy.ndarray` is given:

    > - gray8 MUST be CONTIGUOUS, ALIGNED

    > - if gray8.ndims != 2, width and height MUST be given and gray8.nbytes MUST match width*height

    > - if gray8.ndims == 2, gray8.itemsize MUST be 1 (typically, gray8.dtype is one of numpy.dtype.byte, numpy.dtype.ubyte, numpy.dtype.int8 or numpy.dtype.uint8)

    Example:

      :

          def read_myattr(self):
              enc = tango.EncodedAttribute()
              data = numpy.arange(100, dtype=numpy.byte)
              data = numpy.array((data,data,data))
              enc.encode_jpeg_gray8(data)
              return enc

  encode_jpeg_rgb24(rgb24, width=0, height=0, quality=100.0)

    Encode a 24 bit rgb color image as JPEG format.

    > param rgb24:

    >   an object containning image information

    > type rgb24:

    >   `str` or `numpy.ndarray` or seq< seq<element> >

    > param width:

    >   image width. MUST be given if rgb24 is a string or if it is a `numpy.ndarray` with ndims != 3. Otherwise it is calculated internally.

    > type width:

    >   `int`

    > param height:

    >   image height. MUST be given if rgb24 is a string or if it is a `numpy.ndarray` with ndims != 3. Otherwise it is calculated internally.

    > type height:

    >   `int`

    > param quality:

    >   Quality of JPEG (0=poor quality 100=max quality) (default is 100.0)

    > type quality:

    >   `float`

    Note

    When `numpy.ndarray` is given:

    > - rgb24 MUST be CONTIGUOUS, ALIGNED

    > - if rgb24.ndims != 3, width and height MUST be given and rgb24.nbytes/3 MUST match width*height

    > - if rgb24.ndims == 3, rgb24.itemsize MUST be 1 (typically, rgb24.dtype is one of numpy.dtype.byte, numpy.dtype.ubyte, numpy.dtype.int8 or numpy.dtype.uint8) and shape MUST be (height, width, 3)

    Example:

      :

          def read_myattr(self):
              enc = tango.EncodedAttribute()
              # create an 'image' where each pixel is R=0x01, G=0x01, B=0x01
              arr = numpy.ones((10,10,3), dtype=numpy.uint8)
              enc.encode_jpeg_rgb24(data)
              return enc

  encode_jpeg_rgb32(rgb32, width=0, height=0, quality=100.0)

    Encode a 32 bit rgb color image as JPEG format.

    > param rgb32:

    >   an object containning image information

    > type rgb32:

    >   `str` or `numpy.ndarray` or seq< seq<element> >

    > param width:

    >   image width. MUST be given if rgb32 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type width:

    >   `int`

    > param height:

    >   image height. MUST be given if rgb32 is a string or if it is a `numpy.ndarray` with ndims != 2. Otherwise it is calculated internally.

    > type height:

    >   `int`

    Note

    When `numpy.ndarray` is given:

    > - rgb32 MUST be CONTIGUOUS, ALIGNED

    > - if rgb32.ndims != 2, width and height MUST be given and rgb32.nbytes/4 MUST match width*height

    > - if rgb32.ndims == 2, rgb32.itemsize MUST be 4 (typically, rgb32.dtype is one of numpy.dtype.int32, numpy.dtype.uint32)

    Note

    Encoding with transparency information required cppTango built with TANGO_USE_JPEG options see installation instructions of cppTango

    Example:

      :

          def read_myattr(self):
              enc = tango.EncodedAttribute()
              data = numpy.arange(100, dtype=numpy.int32)
              data = numpy.array((data,data,data))
              enc.encode_jpeg_rgb32(data)
              return enc

  encode_rgb24(rgb24, width=0, height=0)

    Encode a 24 bit color image (no compression)

    > param rgb24:

    >   an object containning image information

    > type rgb24:

    >   `str` or `numpy.ndarray` or seq< seq<element> >

    > param width:

    >   image width. MUST be given if rgb24 is a string or if it is a `numpy.ndarray` with ndims != 3. Otherwise it is calculated internally.

    > type width:

    >   `int`

    > param height:

    >   image height. MUST be given if rgb24 is a string or if it is a `numpy.ndarray` with ndims != 3. Otherwise it is calculated internally.

    > type height:

    >   `int`

    Note

    When `numpy.ndarray` is given:

    > - rgb24 MUST be CONTIGUOUS, ALIGNED

    > - if rgb24.ndims != 3, width and height MUST be given and rgb24.nbytes/3 MUST match width*height

    > - if rgb24.ndims == 3, rgb24.itemsize MUST be 1 (typically, rgb24.dtype is one of numpy.dtype.byte, numpy.dtype.ubyte, numpy.dtype.int8 or numpy.dtype.uint8) and shape MUST be (height, width, 3)

    Example:

      :

          def read_myattr(self):
              enc = tango.EncodedAttribute()
              # create an 'image' where each pixel is R=0x01, G=0x01, B=0x01
              arr = numpy.ones((10,10,3), dtype=numpy.uint8)
              enc.encode_rgb24(data)
              return enc