1. Apparatus for measuring current carried by a conductor, the apparatus comprising:
a differential voltage amplifier having inputs for connection to the conductor at two spaced-apart points thereof, constituting ends of a conductor segment, and
a circuit for converting an output voltage of the amplifier into an electrical current value, said circuit incorporating a microcontroller associated with a programmable memory storing a calibration table in digital form.
2. Apparatus according to claim 1 further including a temperature sensor and correction means arranged to take account of a coefficient of resistivity variation of the conductor as a function of temperature.
3. Apparatus according to claim 1, wherein the memory contains a table for correcting static errors as a function of the current.
4. Apparatus according to claim 1, further including a calibration current generator for generating a predetermined calibration current at a frequency distinguishable from that of the electrical current to be measured, and means for determining or correcting the calibration table responsive to a voltage measured at the calibration current frequency.
5. Apparatus according to claim 1, wherein the circuit for converting comprises, downstream from the differential voltage amplifier, at least two amplifiers selectively put into operation depending on the magnitude of the current.
6. In a vehicle provided with an alternator-starter and a battery, an apparatus according to claim 1 connected to measure battery current.
7. Apparatus for measuring DC or AC current carried by a conductor, comprising:
a differential voltage amplifier having two inputs for connection to the conductor each at one of two spaced-apart points of the conductor thereof, constituting ends of a segment, and
a measurement circuit for converting an output voltage of the amplifier into an electrical current value, said measurement circuit including an input analogdigital converter, a microcontroller, a programmable memory for storing a calibration table in digital form, a generator for generating a calibration current at a frequency sufficiently different from a frequency of the current to be measured for enabling the calibration current to be separated from the current to be measured by filter means, and means for determining or correcting the calibration table responsive to a voltage measured at the calibration current frequency.
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. A system comprising:
a client computer to playback multimedia content and annotations corresponding to different temporal portions of the multimedia content; and
an annotation server, coupled to the client computer, to,
maintain an annotation database having a plurality of annotations corresponding to the multimedia content,
provide the plurality of annotations to the client computer for playback,
send electronic mail messages including annotations to recipients identified by the client computer,
generate new annotations based on received electronic mail messages, and
add the new annotations to the annotation database.
2. A system as recited in claim 1, further comprising a media server to manage streaming the multimedia content to the client computer.
3. A system as recited in claim 1, further comprising a network coupling the client computer to the annotation server.
4. A system as recited in claim 1, wherein the client computer is further to:
present an electronic mail message including a multimedia content identifier to a user,
receive a user selection of the multimedia content identifier,
access a media server to obtain the multimedia content, and
playback the multimedia content to the user.
5. A system as recited in claim 4, wherein the client computer is further to transmit, to the media server, an identifier of a temporal segment of the multimedia content, and wherein the media server is to stream to the client computer the multimedia content beginning with the identified temporal segment.
6. A method comprising:
presenting, to a user, a user interface allowing the user to create a new annotation corresponding to media content; and
including, as part of the user interface, a field via which the user can identify a recipient that is to receive an electronic mail notification of the new annotation.
7. A method as recited in claim 6, further comprising forwarding the new annotation to an annotation server to transmit the electronic mail notification of the new annotation to the recipient.
8. A method as recited in claim 6, further comprising forwarding the new annotation to an annotation server to be added to an annotation set corresponding to the media content.
9. A method as recited in claim 6, further comprising:
allowing the user to identify, via the field of the user interface, a plurality of recipients to receive the electronic mail notification; and
wherein the forwarding comprises forwarding, to each of the plurality of recipients, the electronic mail notification of the new annotation.
10. A method as recited in claim 6, further comprising:
allowing the user to input, via the field of the user interface, a group identifier;
identifying an electronic mail address for each of a plurality of recipients corresponding to the group identifier; and
wherein the forwarding comprises forwarding, to each of the plurality of recipients, the electronic mail notification of the new annotation.
11. A method as recited in claim 6, further comprising:
presenting, as part of the user interface, a default set of recipients to receive the electronic mail notification.
12. One or more computer-readable memories containing a computer program that is executable by a processor to perform the method recited in claim 6.
13. A method comprising:
receiving data for a new annotation corresponding to a temporal range of media content;
generating an electronic mail message including both the content of the new annotation and an identifier of the media content; and
forwarding the electronic mail message to a recipient identified by the data.
14. A method as recited in claim 13, wherein the generating further comprises including, in the electronic mail message, an identifier of the new annotation.
15. A method as recited in claim 13, wherein the generating further comprises including, in the electronic mail message, an identifier of the temporal range of media content.
16. One or more computer-readable memories containing a computer program that is executable by a processor to perform the method recited in claim 13.
17. A method comprising:
receiving an electronic mail notification of a new annotation corresponding to media content, the media content having a plurality of temporal segments;
presenting the electronic mail notification to a user;
receiving a user input to access the media content; and
accessing, upon receiving the user input, a media server to stream one of the plurality of segments that corresponds to the new annotation to the user.
18. A method as recited in claim 17, wherein the presenting comprises displaying annotation content for the new annotation to the user.
19. A method as recited in claim 17, wherein the presenting comprises:
displaying annotation content for the new annotation to the user; and
displaying at least one identifier to the user, the at least one identifier including one or more of:
a content identifier that identifies the media content;
a range identifier that identifies a temporal range of the segment corresponding to the new annotation;
an annotation identifier that identifies the new annotation; and
an annotation set identifier that identifies one or more annotation sets that the new annotation is part of.
20. A method as recited in claim 19, wherein the content identifier comprises a uniform resource locator (URL).
21. A method as recited in claim 17, wherein the receiving a user input comprises receiving a user selection of a uniform resource locator (URL) of the media content.
22. A method as recited in claim 17, wherein the receiving a user input comprises receiving a user selection of an identifier of the annotation.
23. One or more computer-readable media having stored thereon a computer program that, when executed by one or more processors, causes the one or more processors to perform functions including:
receiving an electronic mail notification of a new annotation corresponding to media content, wherein the electronic mail notification includes a user-selectable identifier of the media content;
displaying the electronic mail notification;
receiving a user selection of the identifier; and
accessing, upon receiving the user selection, a media server indicated by the identifier to begin streaming the media content for presentation to the user.
24. One or more computer-readable media as recited in claim 23, wherein the user-selectable identifier comprises a uniform resource locator (URL) that identifies a server and a location at the server where the media content is located.
25. A system comprising:
an interface module to receive data regarding a new annotation corresponding to media content;
a module to generate an electronic mail message regarding the new annotation, the electronic mail message including,
the new annotation content, and
an identifier of the media content to which the new annotation corresponds.
26. A system as recited in claim 25, wherein the electronic mail message further includes an identifier of the temporal range of the media content that the new annotation is associated with.
27. A system as recited in claim 25, wherein the electronic mail message further includes a unique identifier of the new annotation.
28. A system as recited in claim 25, wherein the electronic mail message further includes an identifier of one or more annotation sets that the new annotation is associated with.
29. A system as recited in claim 25, wherein the system comprises an annotation server computer.
30. A system as recited in claim 25, wherein the system comprises a client computer and wherein the interface module comprises a user interface.
31. A method comprising:
receiving an electronic mail notification of an annotation corresponding to media content; and
replying to the electronic mail notification to generate a new annotation corresponding to the media content.
32. A method as recited in claim 31, wherein the replying includes:
obtaining, from the electronic mail notification, an identifier of the annotation; and
including the identifier of the annotation in the reply.
33. A method comprising:
receiving an electronic mail thread including a plurality of electronic mail messages;
creating an annotation from at least one of the electronic mail messages; and
adding the annotation to an annotation database.
34. A method as recited in claim 33, wherein the creating comprises creating a single annotation including each of the plurality of electronic mail messages.
35. A method as recited in claim 33, wherein:
the creating comprises generating, for each of the plurality of electronic mail messages, an annotation; and
the adding comprises adding each of the generated annotations to the annotation database.
36. A method as recited in claim 33, further comprising locating, in the electronic mail thread, an identifier of media content that the annotation corresponds to.
37. One or more computer-readable media having stored thereon a computer program that, when executed by one or more processors, causes the one or more processors to perform functions including:
receiving an electronic mail message; and
extracting both annotation content and annotation identification information from the electronic mail message.
38. One or more computer-readable media as recited in claim 37, wherein the computer program further causes the one or more processors to perform functions including:
creating a new annotation based on the extracted annotation content and the annotation identification information; and
adding the new annotation to an annotation database.
39. One or more computer-readable media as recited in claim 37, wherein the extracting annotation identification information comprises extracting from the email message:
an identifier of media content to which the annotation content corresponds and of a temporal segment, corresponding to the annotation content, of the media content; and
an identifier of an annotation set that a new annotation including the extracted annotation content is to be part of.