1. An information processing apparatus for transmitting content to another apparatus via a network, said information processing apparatus comprising:
an encryption unit operable to encrypt the content;
an authentication unit operable to perform an authentication procedure with the another apparatus when the another apparatus requests permission to receive the encrypted content, said authentication procedure providing an authentication result;
a transmitter operable to transmit a decryption key for decrypting the encrypted content to the another apparatus based on said authentication result;
a first obtaining unit operable to obtain identification information of the another apparatus based on said authentication result;
a first counting unit operable to count a total number of units desiring to receive the encrypted content based on said identification information;
a storage unit operable to store said identification information of the another apparatus; and
a controller operable to control a total number of units approved to receive the encrypted content based on said total number of units desiring to receive the encrypted content.
2. An information processing apparatus according to claim 1, further comprising:
a second obtaining unit operable to obtain a number of additional units desiring to receive the encrypted content from the another apparatus based on said authentication result; and
a second counting unit operable to count a total number of units of the another apparatus desiring to receive the encrypted content based on said number of additional units.
3. An information processing apparatus according to claim 1, further comprising:
an information updating unit operable to delete said identification information stored in said storage unit and to reset said total number of units approved to receive the encrypted content when said decryption key is changed.
4. A method for transmitting content from an information processing apparatus to another apparatus via a network, said method comprising:
encrypting the content;
performing an authentication procedure with the another apparatus when the another apparatus requests permission to receive the encrypted content, said authentication procedure producing an authentication result;
transmitting a decryption key for decrypting the encrypted content to the another apparatus based on said authentication result;
obtaining identification information of the another apparatus based on said authentication result;
counting a total number of units desiring to receive the encrypted content based on said identification information;
storing said identification information of the another apparatus; and
controlling a total number of units approved to receive the encrypted content based on said total number of units desiring to receive the encrypted content.
5. A recording medium having recorded thereon a program for transmitting content from an information processing apparatus to another apparatus via a network, said program comprising:
encrypting the content;
performing an authentication procedure with the another apparatus when the another apparatus requests permission to receive the encrypted content, said authentication procedure producing an authentication result;
transmitting a decryption key for decrypting the encrypted content to the another apparatus based on said authentication result;
obtaining identification information of the another apparatus based on said authentication result;
counting a total number of units desiring to receive the encrypted content based on said identification information;
storing said identification information of the another apparatus; and
controlling a total number of units approved to receive the encrypted content based on said total number of units desiring to receive the encrypted content.
6. An information processing apparatus for receiving content from a first apparatus via a first network, said information processing apparatus comprising:
a first transmitter operable to transmit to the first apparatus a request for permission to receive the content;
a first authentication unit operable to perform a first authentication procedure with the first apparatus, said first authentication procedure producing a first authentication result;
a receiver operable to receive from the first apparatus a first decryption key for decrypting the content based on said first authentication result;
a second transmitter operable to transmit the content received from the first apparatus to a second apparatus via a second network;
a second authentication unit operable to perform a second authentication procedure with said second apparatus when a request for permission to receive the content is made from said second apparatus, said second authentication procedure producing a second authentication result;
a third transmitter operable to transmit a second decryption key to said second apparatus based on said second authentication result;
a first obtaining unit operable to obtain identification information of said second apparatus based on said second authentication result;
a first counting unit operable to count a number of units desiring to receive the content based on said identification information;
a storage unit operable to store said identification information of said second apparatus; and
a controller operable to control a number of units approved to receive the content based on said number of units desiring to receive the content.
7. An information processing apparatus according to claim 6, further comprising:
a decryption unit operable to decrypt the content; and
an encryption unit operable to encrypt the content decrypted by said decryption unit.
8. An information processing apparatus according to claim 6, further comprising:
a fourth transmitter operable to transmit said number of units desiring to receive the content to the first apparatus based on said first authentication result;
a second obtaining unit operable to obtain a number of additional units desiring to receive the content from said second apparatus based on said second authentication result; and
a second counting unit operable to count a total number of units of said second apparatus desiring to receive the content based on said number of additional units.
9. An information processing apparatus according to claim 6, further comprising:
an information updating unit operable to delete said identification information stored in said storage unit and to reset said number of units approved to receive the content when said second decryption key is changed.
10. A method for receiving content in an information processing apparatus from a first apparatus via a first network, said method comprising:
transmitting to the first apparatus a request for permission to receive the content;
performing a first authentication procedure with the first apparatus to obtain a first authentication result;
receiving from the first apparatus a first decryption key for decrypting the content based on said first authentication result;
transmitting the content received from the first apparatus to a second apparatus via a second network;
performing a second authentication procedure with said second apparatus when a request for permission to receive the content is made from said second apparatus, said second authentication procedure producing a second authentication result;
transmitting a second decryption key to said second apparatus based on said second authentication result;
obtaining identification information of said second apparatus based on said second authentication result;
counting a number of units desiring to receive the content based on said identification information;
storing said identification information of said second apparatus; and
controlling a number of units approved to receive the content based on said number of units desiring to receive the content.
11. A recording medium having recorded thereon a program for receiving content in an information processing apparatus from a first apparatus via a first network, said program comprising:
transmitting to the first apparatus a request for permission to receive the content;
performing a first authentication procedure with the first apparatus to obtain a first authentication result;
receiving from the first apparatus a first decryption key for decrypting the content based on said first authentication result;
transmitting the content received from the first apparatus to a second apparatus via a second network;
performing a second authentication procedure with said second apparatus when a request for permission to receive the content is made from said second apparatus, said second authentication procedure producing a second authentication result;
transmitting a second decryption key to said second apparatus based on said second authentication result;
obtaining identification information of said second apparatus based on said second authentication result;
counting a number of units desiring to receive the content based on said identification information;
storing said identification information of said second apparatus; and
controlling a number of units approved to receive the content based on said number of units desiring to receive the content.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An imaging system comprising:
an imager that forms an electronic image of an object in a field of view;
a rotationally symmetric lens assembly disposed between the imager and the object, the lens assembly providing increased collection efficiency for a desired depth of field, whereby the lens assembly causes aberration, compared to a well-focused lens; and
a signal processor connected to the imager, wherein the signal processor receives image data and generates a virtual scan line signal comprising samples taken from a line across the image, wherein the signal processor comprises:
a non-uniform scaler that receives the virtual scan line signal and scales samples in the virtual scan line signal to generate a non-uniformly scaled virtual scan line signal; and
an equalizer that receives the non-uniformly scaled virtual scan line signal and equalizes the non-uniformly scaled virtual scan line signal so as to at least partially compensate for the aberration caused by the lens assembly.
2. An imaging system according to claim 1, wherein the rotationally symmetric lens assembly comprises a generalized axicon lens.
3. An imaging system according to claim 1, wherein the rotationally symmetric lens assembly comprises:
a front negative lens;
a rear positive lens; and
an aperture positioned between the front and rear lenses.
4. An imaging system according to claim 3, wherein the front negative lens is a biconcave lens.
5. An imaging system according to claim 3, wherein the front negative lens is a plano-concave lens.
6. An imaging system according to claim 3, wherein the rear positive lens is a biconvex lens.
7. An imaging system according to claim 3, wherein the rear positive lens is a plano-convex lens.
8. An imaging system according to claim 1, wherein the equalizer is one-dimensional, whereby the imaging system is largely invariant to angular orientation of the virtual scan line.
9. An imaging system according to claim 1, wherein the equalizer has a transfer function that is approximately an inverse of a modulation transfer function of the rotationally symmetric lens assembly.
10. An imaging system according to claim 1, wherein the rotationally symmetric lens assembly has an aperture size greater than a well-focused lens having a similar depth of field as the rotationally symmetric lens assembly, whereby the imaging system generates well-formed images of the object as the object moves across the field of view at a higher speed than if a well-focused lens were utilized.
11. An imaging system comprising:
an imager that forms an electronic image of an object in a field of view;
a rotationally symmetric lens assembly disposed between the imager and the object, the rotationally symmetric lens assembly providing increased collection efficiency for a desired depth of field, whereby the rotationally symmetric lens assembly causes aberration, compared to a well-focused lens, the rotationally symmetric lens assembly comprising:
a front negative lens;
a rear positive lens; and
an aperture positioned between the front and rear lenses; and
an equalizer connected to the imager, wherein the equalizer receives image data and at least partially compensates for the aberration caused by the rotationally symmetric lens assembly.
12. An imaging system according to claim 11, wherein the rotationally symmetric lens assembly is a generalized axicon.
13. An imaging system according to claim 11, wherein the equalizer is one-dimensional.
14. An imaging system according to claim 13, wherein the input to the equalizer is a virtual scan line signal comprising samples taken from a line across the image.
15. An imaging system according to claim 11, wherein the front negative lens is a biconcave lens.
16. An imaging system according to claim 11, wherein the front negative lens is a piano-concave lens.
17. An imaging system according to claim 11, wherein the rear positive lens is a biconvex lens.
18. An imaging system according to claim 11, wherein the rear positive lens is a plano-convex lens.
19. An imaging system according to claim 11, wherein the equalizer has a transfer function that is approximately an inverse of a modulation transfer function of the rotationally symmetric lens assembly.
20. An imaging system according to claim 11, wherein the rotationally symmetric lens assembly has an aperture size greater than a well-focused lens having a similar depth of field as the rotationally symmetric lens assembly, whereby the imaging system generates well-formed images of the object as the object moves across the field of view at a higher speed than if a well-focused lens were utilized.
21. An imaging system according to claim 11, wherein the image comprises a plurality of pixels, the imaging system further comprising:
a plurality of pixel-specific gain elements that scale pixel values individually so as to compensate for nonuniformity in the formation of the intensity of the pixel values.
22. A method comprising:
passing light from an object through a negative lens;
blocking a light from a periphery region of the negative lens while passing light from a central region of the negative lens;
passing the light from the central region of the negative lens through a positive lens;
forming an image of the object based on the light from the positive lens;
generating a virtual scan line signal comprising samples taken from one or more lines across the image at arbitrary angles;
scaling the samples of the virtual scan line signal by non-uniform amounts; and
equalizing the non-uniformly scaled virtual scan line signal so as to at least partially compensate for blurriness caused by one or more of the lenses.