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US 4,837,450 AGranted
Apparatus for reading a film image with controllable illumination and threshold value
AssigneeCanon Kabushiki Kaisha
InventorsSeiichiro Satomura, Masahide Kotera
Life of this patent
Estimating the term…
Abstract
An apparatus for reading a microfilmed image to obtain digital image signal, in which the level of quantizing is determined by measuring the density of image and of background.
Claims90
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading image recorded on the film illuminated by said illuminating means and for outputting image signals representing the image;
- first detection means for detecting an image density of the image recorded on the film on the basis of the image signals from said reading means;
- second detection means for detecting a base density of the film on the basis of the image signals from said reading means;
- means for quantizing the image signals outputted from said reading means;
- and
- means for determining a threshold value for quantizing the image signals on the basis of the thus detected image density and base density.
4 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading line by line the image recorded on the film illuminated by said illuminating means and for outputting image signals representing the image;
- means for dividing the image signals of each reading line, outputting from said reading means, into plural blocks, each block including a predetermined amount of the image signals;
- means for detecting a respective peak value of the image signals in each block;
- means for quantizing the image signals outputted from said reading means;
- and
- means for determining a threshold value for quantizing the image signals on the basis of the the detected peak value of each blocks.
4 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and outputting image signals representing the image;
- means for detecting an image density of an image corresponding to a predetermined partial area of the film on the basis of the image signals from said reading means;
- means for quantizing the image signal outputted from said reading means;
- and
- means for determining a threshold value for quantizing the image signals on the basis of the detected density of an image.
3 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and outputting image signals representing the image;
- first detection means for detecting an output value of said reading means in a state where the film is not illuminated by said illuminating means;
- second detection means for detecting an image density of the image recorded on the film on the basis of the image signals from said reading means in a state where the film is illuminated by said illuminating means;
- means for quantizing the image signals outputted from said reading means;
- and
- means for determining a threshold value for quantizing the image signals on the basis of the thus detected output value and image density.
4 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and for outputting image signals representing the image;
- first detection means for detecting a base density of the film on the basis of an output from said reading means when said reading means reads a non-image area of the film illuminated by said illuminating means;
- and
- means for determining the amount of light for said illuminating means according to the thus detected base density;
- and
- second detection means for detecting an image density of the image based on an output from said reading means when said reading means reads the image recorded on the film illuminated with the thus determined amount of light by said illuminating means.
4 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and for outputting image signals representing the image;
- first detection means for detecting an image density of the image recorded on the film on the basis of the image signals from said reading means;
- second detection means for detecting a base density of the film on the basis of the image signals from said reading means;
- and
- means for identifying an abnormality in said illuminating means on the basis of the thus detected image density and base density.
3 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and for outputting image signals representing the image;
- first detection means for detecting an image density of the image recorded on the film on the basis of an output from said reading means;
- second detection means for detecting a base density of the film on the basis of an output from said reading means;
- and
- means for identifying the position of the image on the film on the basis of the thus detected image density and base density, to determine whether the image is proper or not proper for reading.
3 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and for outputting image signals representing the image;
- first detection means for detecting an image density of the image recorded on the film on the basis of the image signals form said reading means;
- second detection means for detecting a base density of the film on the basis of the image signals from said reading means;
- means for processing the image signals output from said reading means, for image reproduction;
- and
- means for determining a parameter for processing the image signals on the basis of the thus detected image density and base density.
4 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading line by line the image recorded on the film illuminated by said illuminating means and/or outputting image signals representing the image;
- means for dividing the image signals of each reading line, output from said reading means, into plurality blocks, each block including a predetermined amount of the image signals;
- means for detecting a respective peak value of the image signals in each block;
- means for processing the image signals output from said reading means, for image reproduction;
- and
- means for determining a parameter for processing the image signals on the basis of the detected peak value of each block.
4 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and outputting image signals representing the image;
- means for detecting an image density of an image corresponding to as predetermined partial area of the film on the basis of the image signals from said reading means;
- means for processing the image signal output from said reading means, for image reproduction;
- and
- means for determining a parameter for processing the image signals on the basis of the detected density of an image.
3 more elements
A film image reading apparatus comprising:
- means for illuminating a film on which an image is recorded;
- means for reading the image recorded on the film illuminated by said illuminating means and outputting image signals representing the image;
- first detection means for detecting an output value of said reading means in a state where the film is not illuminated by said illuminating means;
- second detection means for detecting an image density of the image record on the film on the basis of the image signals from said reading means in a state where the film is illuminated by said illuminating means;
- means for processing the image signals output from said reading means, for image reproduction;
- and
- means for determining a parameter for processing the image signals on the basis of the thus detected output value and image density.
4 more elements
Dependencies are inferred from the claim text.