def thumbnail_extract(self, metadata: GExiv2.Metadata, size_in_bytes) -> bool:
thumbnail = metadata.get_exif_thumbnail()
if not thumbnail:
previews = metadata.get_preview_properties()
if previews:
# In every RAW file I've analyzed, the smallest preview is always first
preview = previews[0]
thumbnail = metadata.get_preview_image(preview).get_data()
if thumbnail == self.exif_thumbnail_or_preview:
self.minimum_exif_read_size_in_bytes_thumbnail = size_in_bytes
return True
return False
def extract_thumbnail(self, metadata: GExiv2.Metadata) -> None:
# not all files have an exif preview, but all CR2 & CR3 seem to
exif_thumbnail = metadata.get_exif_thumbnail()
self.process_exif_thumbnail(thumbnail=exif_thumbnail)
previews = metadata.get_preview_properties()
self.no_previews = len(previews)
for idx, preview in enumerate(previews):
image = metadata.get_preview_image(preview)
if image.get_width() >= 160 and image.get_height() >= 120:
preview_thumbnail = metadata.get_preview_image(preview).get_data()
if self.has_exif_thumbnail:
self.exif_thumbnail_and_preview_identical = preview_thumbnail == exif_thumbnail
else:
self.exif_thumbnail_or_preview = preview_thumbnail
self.preview_source = PreviewSource(idx).name.replace('_', ' ').capitalize()
self.preview_width = image.get_width()
self.preview_height = image.get_height()
self.preview_extension = image.get_extension()
return
