1. An implantable device, comprising:
a waveform generator to create a waveform for application along each of multiple vectors through a bodily tissue of a patient via electrodes, wherein the duration of each waveform is less than a charging time constant of an electrode-electrolyte interface between each electrode and the bodily tissue and wherein at least one of the vectors is confined to within the patient’s heart tissue or pericardium;
a multiplexor to apply and process the waveform over the multiple vectors;
an impedance measurement module to obtain multiple impedance measurements at least in part via the multiplexor such that one of the multiple impedance measurements is obtained for each of the multiple vectors; and
an evaluator to interpret the multiple impedance measurements in order to estimate a bodily parameter of the patient.
2. The implantable device as recited in claim 1, wherein the multiplexor uses time multiplexation to apply and process the waveform over the multiple vectors.
3. The implantable device as recited in claim 2, wherein the multiplexor signals the impedance measurement module to sense an impedance result for each of the vectors in rapid succession, wherein the speed of the rapid succession emulates simultaneous measurement across the multiple vectors.
4. The implantable device as recited in claim 3, wherein the multiplexor sequentially times a measurement of each of the applied waveforms to occur within a time interval of a physiological circumstance.
5. The implantable device as recited in claim 3, wherein the physiological circumstance comprises an intracardiac pressure state.
6. The implantable device as recited in claim 3, wherein the multiplexor applies a different frequency of the waveform for each of the multiple vectors; and
wherein the multiplexor senses an impedance result associated with each of the multiple waveforms by frequency.
7. The implantable device as recited in claim 1, further comprising a network selector for determining the multiple vectors.
8. The implantable device as recited in claim 7, wherein the network selector weights each of the multiple vectors according to an importance of each vector with respect to the bodily parameter to be estimated.
9. The implantable device as recited in claim 1, further comprising an alert module to actuate an alarm or a patient notification in response to an estimate of the bodily parameter exceeding a threshold, wherein the alarm or patient notification is delivered via the implantable device or via a device external to the patient
10. The implantable device as recited in claim 1, wherein the implantable device interprets the multiple impedance measurements to estimate a degree of heart failure or a degree of pulmonary edema of the patient.
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 method comprising:
forming a cell map comprising a representation of an object to be printed on a printing device, wherein the cell map has a lower resolution than a pixel map comprising a representation of the object, wherein each cell of the cell map corresponds to multiple pixels on the pixel map;
determining a partition of the cell map in which the object is to be rendered;
determining if the partition has already been written-to in the course of a previous rendering of another object:
if the partition has previously been written-to, then rendering the representation of the object in the pixel map with regard to the previous rendering;
if the partition has not previously been written-to, then rendering the representation of the object in the pixel map without regard to any previous rendering; and
printing the rendered representation of the object on the printing device.
2. The method defined in claim 1 wherein determining if the partition has already been written to in the course of a previous rendering of another object comprises setting a flag to indicate overlap of two objects.
3. The method defined in claim 1 further comprising:
updating the cell map after rendering each object.
4. The method defined in claim 3 further comprising repeating the determining steps and the rendering steps for multiple objects.
5. The method defined in claim 1, wherein rendering the representation of the object in the pixel map with regard to the previous rendering comprises rendering the object using color blending, foregroundbackground processing and transparency processing with regard to the previous rendering.
6. The method defined in claim 1, wherein each cell of the cell map is associated with more than one pixel in the pixel map.
7. The method defined in claim 1 further comprising updating each cell in the cell map with data indicating objects associated with one or more cells have been rendered in the pixel map.
8. The method defined in claim 1 wherein the cell map has a resolution in any coordinate of \xbdn of the pixel map, n being an integer.
9. The method defined in claim 1 wherein each said cell corresponds to a section of said pixel map having a dimension of 2X pixels by 2Y pixels, wherein both said X and said Y are integers.
10. A method of, comprising:
determining a partition of a low resolution map associated with an object to be rendered;
determining if the partition has already been written to when another object was rendered;
if the partition has previously been written to, then rendering the representation of the object in a pixel map with regard to the previous rendering;
if the partition has not previously been written to, then rendering the representation of the object in the pixel map without regard to any previous rendering; and
printing the rendered representation of the object on the printing device.
11. A method as described in claim 10 further comprising repeating the acts of determining and rendering for multiple objects.
12. A method as described in claim 10 wherein the partition corresponds to predetermined pixels in the pixel map.
13. A method as described in claim 10 further comprising converting an object description into a representation having at least one sub-partition of said partition, each said sub-partition corresponding to at least one pixel.
14. A computer readable medium having stored thereon a plurality of instructions that, when executed by at least one processor, cause the processor to perform acts comprising:
converting from an object described in pixel coordinates into an object representation in at least one cell, each cell representing an area corresponding to a multiple quantity of pixels of a pixel map;
forming an indication that the object is to be rendered on the pixel map without regard to destination dependent operations if all of the cells of the object representation are not written-to in a cell map;
updating the cell map to include the cells of the object representation as written-to; and
printing a rendered representation of the object on a printing device.
15. The computer readable medium defined in claim 14 wherein the instructions further cause the processor to repeat the converting, the forming, and the updating, for multiple objects.
16. The computer readable medium defined in claim 14 wherein the instructions further cause the processor to perform, if any of the cells of the object representation are written-to in the cell map, forming an indication that the object is not to be rendered on the pixel map with regard to destination dependent operations.
17. The computer readable medium defined in claim 14 wherein each of the cells of the cell map that is written to is represented in a memory by data indicating the cell is written-to.
18. The computer readable medium defined in claim 14 wherein each cell of the cell map has a resolution in a coordinate of \xbdn of the resolution of each pixel in the pixel map, n representing an integer.
19. A rendering system to render a printing device pixel map comprising:
a processor; and
a memory to store a cell-based map arranged according to cells to describe each cell written to by an object, each cell corresponding to a plural number of pixels in the pixel map, and to store a plurality of instructions that when executed by the processor, cause the processor to perform acts comprising:
converting a description of an object to from pixel coordinates into a cell-based map;
determining whether at least one cell of the representation was previously written-to on the cell-based map;
if no cells of the representation are written-to on the cell-based map, rendering the object in the pixel map without regard to destination dependent operations;
subsequent to the determining, storing for each cell of the representation in the cell based map, an indication that the cell is written-to in the cell-based map; and
printing the rendered representation of the object on the printing device.
20. The rendering system defined in claim 19 further comprising a pixel map generation unit to render the object on the pixel map if cells of the representation are written-to on the cell-based map.
21. The rendering system defined in claim 19 further comprising a circuit to couple a host computer to the processor to receive the description of the object according to pixel coordinates.
22. The rendering system defined in claim 19 wherein the cell map has a resolution in a coordinate of \xbdn of the pixel map, n representing an integer.
23. The rendering system defined in claim 19 wherein each cell is represented by fewer bits than each pixel of the in the pixel map.
24. The rendering system defined in claim 19 wherein each cell is represented by one bit.
25. A printing device comprising:
first means for determining a partition of a low resolution map associated with an object to be rendered;
second means for determining if the partition has already been written to when another object was rendered;
third means for, if the partition has previously been written to, rendering the representation of the object in a pixel map with regard to the previous rendering;
fourth means for, if the partition has not previously been written to, rendering the representation of the object in the pixel map without regard to any previous rendering; and
fifth means for printing the rendered representation of the object on the printing device.
26. A printing device as described in claim 25 additionally comprising means for updating the low resolution map after rendering each object.
27. A printing device as described in claim 25 further comprising means to maintain said map by converting the cells representing the object into destination cells in the map.
28. A printing device as described in claim 25 wherein each of the cells in the map is described by one of being a destination cell and not being a destination cell.
29. A printing device as described in claim 25 wherein the cells each have a resolution in a coordinate of \xbdn of the described pixels, n representing an integer.
30. A printing device as described in claim 25 further comprising fourth means to couple a computer to said second means wherein the computer generates the object described according to pixels.