Function libheif_sys::heif_context_encode_thumbnail

pub unsafe extern "C" fn heif_context_encode_thumbnail(
    arg1: *mut heif_context,
    image: *const heif_image,
    master_image_handle: *const heif_image_handle,
    encoder: *mut heif_encoder,
    options: *const heif_encoding_options,
    bbox_size: c_int,
    out_thumb_image_handle: *mut *mut heif_image_handle
) -> heif_error

Encode the ‘image’ as a scaled down thumbnail image. The image is scaled down to fit into a square area of width ‘bbox_size’. If the input image is already so small that it fits into this bounding box, no thumbnail image is encoded and NULL is returned in ‘out_thumb_image_handle’. No error is returned in this case. The encoded thumbnail is automatically assigned to the ‘master_image_handle’. Hence, you do not have to call heif_context_assign_thumbnail().