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visualdynamics.core.photos

photos

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

A Photos object is an ordered set of named images — the setup and instrumentation photos a test report leans on. It keeps the file bytes verbatim (PNG or JPEG), so nothing is re-encoded and what went in is exactly what comes out, in the project file and in the report.

Classes:

Name Description
Photos

Named images, in the order they arrived.

Classes

Photos 

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

Named images, in the order they arrived.

Setup photographs belong with the data they document — where the accelerometers went, how the article was hung — so they are a project object like any other and ride the .vdyn file. The bytes are kept encoded as they arrived rather than decoded into arrays: a report embeds them, and re-encoding a JPEG to store it would lose a generation for nothing.

Attributes: names: What each photo is called, which is what a report figure is captioned with. formats: The encoding of each — 'png', 'jpeg', 'heic'. images: The encoded bytes, one per photo.

Methods:

Name Description
rename

Give the photo at index a new name; names stay unique.
delete_photos

Remove the photos at picks (indices).
add_file

Add an image file; the name is the file's own stem, deduped.
plot

Show these photos, as the app shows them.
Source code in src/visualdynamics/core/photos.py 
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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

Give the photo at index a new name; names stay unique.

Source code in src/visualdynamics/core/photos.py 
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def rename(self, index: int, name: str) -> None:
    """Give the photo at `index` a new name; names stay unique."""
    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 
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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 an image file; the name is the file's own stem, deduped.

Returns the name the photo landed under.

Source code in src/visualdynamics/core/photos.py 
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def add_file(self, path: str | os.PathLike) -> str:
    """Add an image file; the name is the file's own stem, deduped.

    Returns the name the photo landed under.
    """
    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 these photos, as the app shows them.

Source code in src/visualdynamics/core/photos.py 
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def plot(self, picks: Sequence[int] | None = None, **kwargs: Any) -> Any:
    """Show these photos, as the app shows them."""
    from ..plot import plot_photos
    return plot_photos(self, picks, **kwargs)