# Options

pillow_heif.options.DECODE_THREADS = 4

  Maximum number of threads to use for decoding images(when it is possible)

  When use pillow_heif as a plugin you can set it with: register_*_opener(decode_threads=8)

pillow_heif.options.THUMBNAILS = True

  Option to enable/disable thumbnail support

  When use pillow_heif as a plugin you can set it with: register_*_opener(thumbnails=False)

pillow_heif.options.DEPTH_IMAGES = True

  Option to enable/disable depth image support

  When use pillow_heif as a plugin you can set it with: register_*_opener(depth_images=False)

pillow_heif.options.QUALITY = None

  Default encoding quality

  Note

  Quality specified during calling `save` has higher priority then this.

  Possible values: None, -1, range(0-100). Set -1 for lossless quality or from 0 to 100, where 0 is lowest and 100 is highest.

  Note

  Also for lossless encoding you should specify `chroma=444` during save.

  When use pillow_heif as a plugin you can set it with: register_*_opener(quality=-1)

pillow_heif.options.SAVE_HDR_TO_12_BIT = False

  Should 16 bit images be saved to 12 bit instead of 10 bit``

  When use pillow_heif as a plugin you can set it with: register_*_opener(save_to_12bit=True)

pillow_heif.options.ALLOW_INCORRECT_HEADERS = False

  Can or not the `size` of image in header differ from decoded one.

  Note

  If enabled, `Image.size` can change after loading for images where it is invalid in header.

  To learn more read: here

  When use pillow_heif as a plugin you can set it with: register_*_opener(allow_incorrect_headers=True)

pillow_heif.options.SAVE_NCLX_PROFILE = True

  Should be `nclx` profile saved or not.

  Default for all previous versions(pillow_heif<0.14.0) was NOT TO save nclx profile, due to an old bug in Apple software refusing to open images with nclx profiles. Apple has already fixed this and there is no longer a need to not save the default profile.

  Note

  save_nclx_profile specified during calling `save` has higher priority than this.

  When use pillow_heif as a plugin you can unset it with: register_*_opener(save_nclx_profile=False)

pillow_heif.options.PREFERRED_ENCODER = {'AVIF': '', 'HEIF': ''}

  Use the specified encoder for format.

  You can get the available encoders IDs using `libheif_info()` function.

  When use pillow_heif as a plugin you can set this option with `preferred_encoder` key.

pillow_heif.options.PREFERRED_DECODER = {'AVIF': '', 'HEIF': ''}

  Use the specified decoder for format.

  You can get the available decoders IDs using `libheif_info()` function.

  When use pillow_heif as a plugin you can set this option with `preferred_decoder` key.

## Example of use

    import pillow_heif

    pillow_heif.options.THUMBNAILS = False
    pillow_heif.options.DECODE_THREADS = 1

## Overriding multiple options at once

When registering a Pillow plugin with `pillow_heif.register_heif_opener()`

    register_heif_opener(thumbnails=False, quality=100, decode_threads=10)