visualdynamics.core.photos

photos

Photos: pictures of the test, saved in the project.

A Photos object is an ordered set of named images, such as the setup and instrumentation photos used in a test report. It keeps the file bytes exactly as read (PNG or JPEG), so nothing is re-encoded and the same bytes go into the project file and the report.

Classes:

Name	Description
Photos	Named images, in the order they were added.

Classes

Photos

Photos(names: Sequence[str] | None = None, formats: Sequence[str] | None = None, images: Sequence[bytes] | None = None)

Named images, in the order they were added.

Setup photos (where the accelerometers were placed, how the test article was supported) belong with the data they document, so they are a project object like any other and are saved in the .vdyn file. The bytes are kept encoded as they were read, not decoded into arrays, because a report embeds them and re-encoding a JPEG to store it would reduce its quality.

Attributes: names: The name of each photo, which is also its caption in a report. formats: The encoding of each, for example 'png' or 'jpeg'. images: The encoded bytes, one per photo.

Raises ValueError if names, formats and images differ in length.

Methods:

Name	Description
rename	Rename the photo at index.
delete_photos	Remove the photos at picks (indices).
add_file	Add a PNG or JPEG file, named after the file without its extension.
plot	Show the photos at picks (all of them by default) as the app shows them.

Source code in src/visualdynamics/core/photos.py

def __init__(self, names: Sequence[str] | None = None,
             formats: Sequence[str] | None = None,
             images: Sequence[bytes] | None = None) -> None:
    self.names: list[str] = [str(name) for name in (names or [])]
    self.formats: list[str] = [str(fmt) for fmt in (formats or [])]
    self.images: list[bytes] = [bytes(image) for image in (images or [])]
    if not (len(self.names) == len(self.formats) == len(self.images)):
        raise ValueError('names, formats and images must match up')

Methods:

rename

rename(index: int, name: str) -> None

Rename the photo at index.

Raises ValueError if the name is blank or another photo already has it.

Source code in src/visualdynamics/core/photos.py

def rename(self, index: int, name: str) -> None:
    """Rename the photo at `index`.

    Raises ValueError if the name is blank or another photo already
    has it.
    """
    name = str(name).strip()
    if not name:
        raise ValueError('a photo needs a name')
    if name in self.names and self.names.index(name) != index:
        raise ValueError(f"there is already a photo named '{name}'")
    self.names[index] = name

delete_photos

delete_photos(picks: Sequence[int]) -> None

Remove the photos at picks (indices).

Source code in src/visualdynamics/core/photos.py

def delete_photos(self, picks: Sequence[int]) -> None:
    """Remove the photos at `picks` (indices)."""
    doomed = set(picks)
    keep = [i for i in range(self.num_photos) if i not in doomed]
    self.names = [self.names[i] for i in keep]
    self.formats = [self.formats[i] for i in keep]
    self.images = [self.images[i] for i in keep]

add_file

add_file(path: str | PathLike) -> str

Add a PNG or JPEG file, named after the file without its extension.

If a photo already has that name, a number is added, as in 'setup (2)'. Returns the name given to the photo. Raises ValueError for any other kind of file.

Source code in src/visualdynamics/core/photos.py

def add_file(self, path: str | os.PathLike) -> str:
    """Add a PNG or JPEG file, named after the file without its extension.

    If a photo already has that name, a number is added, as in
    ``'setup (2)'``. Returns the name given to the photo. Raises
    ValueError for any other kind of file.
    """
    extension = os.path.splitext(path)[1].lower()
    if extension not in FORMATS:
        raise ValueError(
            f'Not a photo (want png or jpeg): {os.path.basename(path)}')
    name = os.path.splitext(os.path.basename(path))[0]
    base, n = name, 1
    while name in self.names:
        n += 1
        name = f'{base} ({n})'
    with open(path, 'rb') as source:
        self.images.append(source.read())
    self.names.append(name)
    self.formats.append(FORMATS[extension])
    return name

plot

plot(picks: Sequence[int] | None = None, **kwargs: Any) -> Any

Show the photos at picks (all of them by default) as the app shows them.

Source code in src/visualdynamics/core/photos.py

def plot(self, picks: Sequence[int] | None = None, **kwargs: Any) -> Any:
    """Show the photos at `picks` (all of them by default) as the app shows them."""
    from ..plot import plot_photos
    return plot_photos(self, picks, **kwargs)