pytoshop.codecs

Coders and decoders for the various compression types in PSD.

pytoshop.codecs.compress_constant_raw(fd, value, width, rows, depth, version)[source]

Write a virtual image containing a constant to a raw stream.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • value (int) – The constant value in the generated virtual image.
  • width (int) – The width of the image, in pixels.
  • rows (int) – The number of rows in the image, in pixels. This is height * num_channels.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_constant_rle(fd, value, width, rows, depth, version)[source]

Write a virtual image containing a constant to a runlength-encoded stream.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • value (int) – The constant value in the generated virtual image.
  • width (int) – The width of the image, in pixels.
  • rows (int) – The number of rows in the image, in pixels. This is height * num_channels.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_constant_zip(fd, value, width, rows, depth, version)[source]

Write a virtual image containing a constant to a zip compressed stream.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • value (int) – The constant value in the generated virtual image.
  • width (int) – The width of the image, in pixels.
  • rows (int) – The number of rows in the image, in pixels. This is height * num_channels.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_constant_zip_prediction(fd, value, width, rows, depth, version)[source]

Write a virtual image containing a constant to a zip with prediction compressed stream.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • value (int) – The constant value in the generated virtual image.
  • width (int) – The width of the image, in pixels.
  • rows (int) – The number of rows in the image, in pixels. This is height * num_channels.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_image(fd, image, compression, shape, num_channels, depth, version)[source]

Write an image with the given compression type.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • image (2-D numpy array or scalar) – The image to compress. Must be unsigned integer with 8, 16 or 32 bits. If depth is 1, the array should have dtype uint8 with a byte per pixel. If a scalar, a “virtual” image will be used as if the image contained only that constant value.
  • compression (enums.Compression) – The compression format to use. See enums.Compression.
  • shape (2-tuple of int) – The shape of the image (height, width). If image is an array, the shape is used to confirm it has the correct shape. If image is a constant, shape is used to generate the virtual constant image.
  • num_channels (int) – The number of color channels in the image. If image is an array, the num_channels is used to confirm it has the correct number of channels. If image is a constant, num_channels is used to generate the virtual constant image.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth. If image is an array, the depth is used to confirm it has the correct number of channels. If image is a constant, depth is used to generate the virtual constant image.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_raw(fd, image, depth, version)[source]

Write a Numpy array to raw bytes in a file.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • image (2-D numpy array) – The image to compress. Must be unsigned integer with 8, 16 or 32 bits. If depth is 1, the array should have dtype uint8 with a byte per pixel.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_rle(fd, image, depth, version)[source]

Write a Numpy array to a run length encoded stream.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • image (2-D numpy array) – The image to compress. Must be unsigned integer with 8, 16 or 32 bits. If depth is 1, the array should have dtype uint8 with a byte per pixel.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_zip(fd, image, depth, version)[source]

Write a Numpy array to a zip (zlib) compressed stream.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • image (2-D numpy array) – The image to compress. Must be unsigned integer with 8, 16 or 32 bits. If depth is 1, the array should have dtype uint8 with a byte per pixel.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.compress_zip_prediction(fd, image, depth, version)[source]

Write a Numpy array to a zip (zlib) with prediction compressed stream.

Not supported for 1- or 32-bit images.

Parameters:
  • fd (file-like object) – Writable file-like object, open in binary mode.
  • image (2-D numpy array) – The image to compress. Must be unsigned integer with 8, 16 or 32 bits. If depth is 1, the array should have dtype uint8 with a byte per pixel.
  • depth (enums.ColorDepth) – The bit depth of the image. See enums.ColorDepth.
  • version (enums.Version) – The version of the PSD file. See enums.Version.
pytoshop.codecs.decompress_image(data, compression, shape, depth, version)[source]

Decompress data with the given compression.

Parameters:
Returns:

image – The image data as a Numpy array.
Return type:

numpy array
pytoshop.codecs.decompress_raw(data, shape, depth, version)[source]

Converts raw data to a Numpy array.

Parameters:
Returns:

image – The image data as a Numpy array. If depth is 1, the array is expanded to uint8 with a byte per pixel.
Return type:

numpy array
pytoshop.codecs.decompress_rle(data, shape, depth, version)[source]

Decompress run length encoded data.

Parameters:
Returns:

image – The image data as a Numpy array. If depth is 1, the array is expanded to uint8 with a byte per pixel.
Return type:

numpy array
pytoshop.codecs.decompress_zip(data, shape, depth, version)[source]

Decompress zip (zlib) encoded data.

Parameters:
Returns:

image – The image data as a Numpy array. If depth is 1, the array is expanded to uint8 with a byte per pixel.
Return type:

numpy array
pytoshop.codecs.decompress_zip_prediction(data, shape, depth, version)[source]

Decompress zip (zlib) with prediction encoded data.

Not supported for 1- or 32-bit images.

Parameters:
Returns:

image – The image data as a Numpy array. If depth is 1, the array is expanded to uint8 with a byte per pixel.
Return type:

numpy array
pytoshop.codecs.normalize_image(image, depth)[source]