1. An electronic camera comprising:
(a) an image sensor for converting an optical image relating to a photographic object into electric signals;
(b) a processor for compress-processing image data corresponding to the electric signals at a predetermined compression ratio for each of a plurality of blocks to obtain compressed image data,
wherein the processor compares a data amount of the compressed image data with a predetermined amount of data, and compress-processes again the image data at a compression ratio greater than the predetermined compression ratio only when the data amount of the compressed image data exceeds the predetermined amount of data; and
(c) a recorder for storing the compressed image data compress-processed by the processor in a memory medium.
2. The electronic camera of claim 1, wherein the processor compress-processes the image data using a quantization table, and only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor compress-processes again the image data by altering the compression ratio through changing the quantization table.
3. The electronic camera of claim 1, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor compress-processes again the image data by altering the compression ratio on the basis of at least one of a number of blocks which have been compress-processed and a coefficient.
4. The electronic camera of claim 3, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor compress-processes again the image data using a quantization table representing the following expression:
n-th quantization table=(quantization table determined by the (n\u22121)th alteration)\xd7\u03b1n,
where \u03b1n denotes an arbitrary coefficient.
5. The electronic camera of claim 3, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor alters the compression ratio by changing the coefficient on the basis of the data amount of the image data, and compress-processes again the image data.
6. The electronic camera of claim 3, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor alters the compression ratio by changing the coefficient on the basis of the predetermined amount of data, and compress-processes again the image data.
7. The electronic camera of claim 3, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor alters the compression ratio by changing the coefficient in accordance with a number of changing of the coefficient, and compress-processes again the image data.
8. The electronic camera of claim 1, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor alters the compression ratio by changing the coefficient on the basis of at least a ratio of a number of processed blocks to a number of entire blocks and a coefficient, and compress-processes again the image data.
9. The electronic camera of claim 8, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor compress-processes again the image data using a quantization table representing the following expression:
n-th quantization table=(quantization table determined by (n\u22121)th alteration)\xd7((number of total blocks)(number of processed blocks))\xd7(n-th coefficient),
where \u03b1n denotes an arbitrary coefficient.
10. The electronic camera of claim 8, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor alters the compression ratio by changing the coefficient on the basis of the data amount of the image data, and compress-processes again the image data.
11. The electronic camera of claim 8, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor alters the compression ratio by changing the coefficient on the basis of the predetermined amount of data, and compress-processes again the image data.
12. The electronic camera of claim 8, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the processor alters the compression ratio by changing the coefficient in accordance with a number of changing of the coefficient, and compress-processes again the image data.
13. The electronic camera of claim 1, wherein the predetermined amount of data can be altered according to a remaining memory capacity of the memory medium.
14. An image data processing apparatus comprising:
(a) an input device for inputting image data; and
(b) a processor for compress-processing the image data for each of a plurality of blocks at a predetermined compression ratio to obtain compressed image data,
wherein the processor compares a data amount of the compressed image data with a predetermined amount of data, and compress-processes again the image data at a compressing ratio greater than the predetermined compression ratio only when the data amount of the compressed image data exceeds the predetermined amount of data.
15. An image data processing method comprising the steps of:
(a) inputting image data; and
(b) compress-processing the image data for each of a plurality of blocks at a predetermined compression ratio, thereby obtaining compressed image data,
wherein the step of the compress-processing the image data compares an amount of data of the compressed image data with a predetermined amount of data, and compress-processes again the image data at a compressing ratio greater than the predetermined compression ratio only when the data amount of the compressed image data exceeds the predetermined amount of data.
16. The image data processing method of claim 15, wherein the step of inputting comprises the step of converting an optical image relating to a photographic object into electric signals, thereby obtaining converted electric signals, and obtaining image data in accordance with the converted electric signals.
17. The image data processing method of claim 16, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of compress-processing the image data using a quantization table, and compress-processing again the image data by altering the compression ratio through changing the quantization table.
18. The image data processing method of claim 16, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of compress-processing again the image data by altering the compression ratio on the basis of at least one of a number of blocks which have been compress-processed and a coefficient.
19. The image data processing method of claim 18, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of compress-processing again the image data using a quantization table representing the following expression:
n-th quantization table=(quantization table determined by the (n\u22121)th alteration)\xd7\u03b1n,
where \u03b1n denotes an arbitrary coefficient.
20. The image data processing method of claim 18, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of altering the compression ratio by changing the coefficient on the basis of the data amount of the image data, and compress-processing again the image data.
21. The image data processing method of claim 18, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of altering the compression ratio by changing the coefficient on the basis of the predetermined amount of data, and compress-processing again the image data.
22. The image data processing method of claim 18, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of altering the compression ratio by changing the coefficient in accordance with a number of changing of the coefficient, and compress-processing again the image data.
23. The image data processing method of claim 16, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of altering the compression ratio by changing the coefficient on the basis of at least a ratio of a number of processed blocks to a number of entire blocks and a coefficient, and compress-processing again the image data.
24. The image data processing method of claim 23, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of compress-processing again the image data using a quantization table representing the following expression:
n-th quantization table=(quantization table determined by (n\u22121)th alteration)\xd7((number of total blocks)(number of processed blocks))\xd7(n-th coefficient),
where \u03b1n denotes an arbitrary coefficient.
25. The image data processing method of claim 23, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of altering the compression ratio by changing the coefficient on the basis of the data amount of the image data, and compress-processing again the image data.
26. The image data processing method of claim 23, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of altering the compression ratio by changing the coefficient on the basis of the predetermined amount of data, and compress-processing again the image data.
27. The image data processing method of claim 23, wherein only when the data amount of the compressed image data exceeds the predetermined amount of data, the step of obtaining compressed image data comprises the step of altering the compression ratio by changing the coefficient in accordance with a number of changing of the coefficient, and compress-processing again the image data.
28. The image data processing method of claim 16, wherein the predetermined amount of data can be altered according to a remaining memory capacity of the memory medium.
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 antenna system comprising:
one of a solid and a hollow metallic substantially cylindrical element having opposed first and second ends and forming a cavity along a longitudinal section thereof, said cavity having at least one peripheral wall;
at least one metallic radiating element adapted to radiate a radiation lobe substantially only in a direction of at least one of said first end and said second end disposed within said cavity;
a filler material disposed within said cavity; and
a radome covering said cavity, said radome being flush with an outer surface of said metallic cylindrical element.
2. An antenna system in accordance with claim 1, wherein said at least one metallic radiating element comprises a metallic material having a form selected from the group consisting of wire, rod, strip and ribbon.
3. An antenna system in accordance with claim 2, wherein said at least one metallic radiating element comprises at least one elongated segment oriented parallel to a longitudinal axis of said solid metallic cylindrical element and at least one connecting segment connecting said at least one elongated segment with said at least one peripheral wall.
4. An antenna system in accordance with claim 1 further comprising at least one tuning means for self-tuning said antenna system and at least one calibration means for self-calibrating said antenna system and a sourcereceiver excitation system.
5. An antenna system in accordance with claim 4, wherein said at least one tuning means comprises means for tuning said at least one metallic radiating element to an impedance of about 50 ohms at a frequency of interest.
6. An antenna system in accordance with claim 5, wherein said tuning means comprises an array of delay lines connected in a switchable combination and physically incorporated into one of a printed circuit board and a discretely packaged RF circuitry.
7. An antenna system in accordance with claim 1, said antenna system integral with one of a drill head and a drill string of an in-ground directional drilling apparatus.
8. In an underground telemetry system comprising an antenna system comprising at least one metallic radiating element, the improvement comprising:
said at least one metallic radiating element having one of a single and a dual top loaded folded monopole configuration and disposed within a metallic housing.
9. An underground telemetry system in accordance with claim 8, wherein said metallic housing is a solid metallic cylinder having opposed first and second ends and forming a cavity along a longitudinal section thereof, said cavity having at least one peripheral wall.
10. An underground telemetry system in accordance with claim 9, wherein a filler material is disposed within said cavity and said cavity is covered by a radome which is flush with an outer surface of said solid metallic cylinder.
11. An underground telemetry system in accordance with claim 8, wherein said at least one metallic radiating element comprises a metallic material having a form selected from the group consisting of wire, rod, strip and ribbon.
12. An underground telemetry system in accordance with claim 8 further comprising at least one tuning means for self-tuning said antenna system and at least one calibration means for self-calibrating said antenna system.
13. An underground telemetry system in accordance with claim 12, wherein said at least one tuning means comprises means for tuning said at least one metallic radiating element to an impedance of about 50 ohms at a frequency of interest.
14. An underground telemetry system in accordance with claim 13, wherein said at least one tuning means comprises an array of delay lines connected in a switchable combination and physically incorporated into a printed circuit board.
15. An underground telemetry system in accordance with claim 9, wherein said at least one metallic radiating element is oriented to radiate a radiation lobe substantially only in a direction of at least one of said first end and said second end of said solid metallic cylinder.