ImageMagick Writer-Reader¶
ImageMagick Writer-Reader (IMWRI) is a plugin that can read and write many image formats.
- imwri.Write(clip clip, string imgformat, string filename[, int firstnum=0, int quality=75, bint dither=True, string compression_type, bint overwrite=False, clip alpha])¶
- Supported input formats for writing:
ImageMagick with Quantum Depth 16 and HDRI: 8-16 bit integer, 32 bit float
Write will write each frame to disk as it’s requested. If a frame is never requested it’s also never written to disk.
- Parameters:
- clip
Input clip. RGB and Gray supported. See list for accepted inputs.
- imgformat
The name of the output format. Examples of supported format strings are “JPEG”, “PNG”, and “DPX”. Visit the ImageMagick website for a full list.
- filename
The filename string must have one or more frame number substitutions. The syntax is printf style. For example “image%06d.png” or “/images/%d.jpg” is common usage.
- firstnum
The first image number in the sequence to write.
- quality
Quality adjustment for formats where it’s applicable. Range is 0 to 100.
- dither
Use Floyd–Steinberg dithering if the input needs to be reduced in depth.
- compression_type
Select the specific compression type for imgformats that have more than one possible compression method. Recognized constants are: Undefined, None, BZip, DXT1, DXT3, DXT5, Fax, Group4, JPEG, JPEG2000, LosslessJPEG, LZW, RLE, Zip, ZipS, Piz, Pxr24, B44, B44A, LZMA, JBIG1, JBIG2
- overwrite
Overwrite already existing files. This option also disables the requirement that output filenames contain a number.
- alpha
A grayscale clip containing the alpha channel for the image to write. Apart from being grayscale, its properties must be identical to the main clip.
- imwri.Read(string[] filename[, int firstnum=0, bint mismatch=False, bint alpha=False, bint float_output = False])¶
Possible output formats when reading: 8-16 bit integer and 32 bit float
Note that by default 8-16 bit images are returned as integer and 32 bit images as float. When reading half precision float images you have to manually set float_output to have the unmodified floating point range returned.
Read is a simple function for reading single or series of images and returning them as a clip.
- Parameters:
- filename
The filename argument has two main modes. Either it takes a list of 1 or more files to open in the given order, or it takes a single filename string with one or more frame number substitutions. The syntax is printf style. For example “image%06d.png” or “/images/%d.jpg” is common usage.
- firstnum
The first image number to start reading from when reading a sequence.
- mismatch
Allow reading of multiple images with different resolutions. If required and not set, an error will be generated.
- alpha
Return the alpha channel from the read images as a separate grayscale clip. Note that an alpha channel clip is always returned when this parameter is set, even for image formats without support for it.
- float_output
Always return the read image in a float format. Due to the output format guessing this option can be useful when reading half precision float images.