1. An image-processing device applying a predetermined process to input image data so as to output the processed image data, the image-processing device comprising:
a medium-density detection unit detecting a medium-density field of an image represented by said image data;
an expansion unit applying an expansion process to said medium-density field detected by said medium-density detection unit; and
a non-character edge judgment unit judging said medium-density field applied with said expansion process by said expansion unit as a non-character edge field of said image represented by said image data.
2. The image-processing device as claimed in claim 1, wherein said expansion unit applies said expansion process after applying a contraction process to said medium-density field detected by said medium-density detection unit.
3. The image-processing device as claimed in claim 1, wherein said medium-density detection unit detects said medium-density field of said image represented by said image data by performing a pattern matching with respect to a multiple-line pattern.
4. The image-processing device as claimed in claim 1, further comprising an edge detection unit detecting an edge of said image represented by said image data.
5. An image-reading device comprising:
an image-reading unit reading an image of a subject copy by performing a color separation to said image of said subject copy so as to generate image data; and
an image-processing unit applying a predetermined process to said image data supplied from said image-reading unit so as to output the processed image data, the image-processing unit including:
a medium-density detection unit detecting a medium-density field of an image represented by said image data;
an expansion unit applying an expansion process to said medium-density field detected by said medium-density detection unit; and
a non-character edge judgment unit judging said medium-density field applied with said expansion process by said expansion unit as a non-character edge field of said image represented by said image data.
6. An image-forming device comprising:
an image-processing unit applying a predetermined process to input image data so as to output the processed image data, the image-processing unit including a medium-density detection unit detecting a medium-density field of an image represented by said image data, an expansion unit applying an expansion process to said medium-density field detected by said medium-density detection unit, and a non-character edge judgment unit judging said medium-density field applied with said expansion process by said expansion unit as a non-character edge field of said image represented by said image data; and
an image-outputting unit outputting the image by forming the image based on said processed image data output from said image-processing unit and transferring the formed image on a sheet.
7. A color-copying device comprising:
an image-reading unit reading an image of a subject copy by performing a color separation to said image of said subject copy so as to generate image data;
an image-processing unit applying a predetermined process to said image data supplied from said image-reading unit so as to output the processed image data, the image-processing unit including, a medium-density detection unit detecting a medium-density field of an image represented by said image data, an expansion unit applying an expansion process to said medium-density field detected by said medium-density detection unit, and a non-character edge judgment unit judging said medium-density field applied with said expansion process by said expansion unit as a non-character edge field of said image represented by said image data; and
an image-outputting unit outputting the image by forming the image based on said processed image data output from said image-processing unit and transferring the formed image on a sheet.
8. The color-copying device as claimed in claim 7, further comprising a control unit analyzing a print command supplied from an external apparatus so as to cause said image-outputting unit to print out image information supplied from said external apparatus.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. An image forming apparatus comprising:
a first image bearing member;
first charging means for charging the first image bearing member, a vibration voltage being applied to the first charging means;
a second image bearing member; and
second charging means for charging the second image bearing member, a vibration voltage being applied to the second charging means,
wherein a first mode in which toner images formed on the first image bearing member and the second image bearing member are transferred to a transfer medium and a second mode in which the toner image formed on the second image bearing member is transferred to the transfer medium without forming the toner image on the first image bearing member are selectable, and
wherein when the second mode is selected, the magnitude of the vibration voltage applied to the first charging means is smaller than the vibration voltage applied when the first mode is selected.
2. An apparatus according to claim 1, wherein when the second mode is selected, the magnitude of the peak-to-peak vibration voltage applied to the first charging means is smaller than the peak-to-peak vibration voltage applied when the first mode is selected.
3. An apparatus according to claim 2, wherein when the second mode is selected, the magnitude of the peak-to-peak vibration voltage applied to the first charging means is zero.
4. An apparatus according to claim 2, wherein when the second mode is selected, the magnitude of the vibration voltage frequency applied to the first charging means is smaller than the vibration voltage frequency applied when the first mode is selected.
5. An apparatus according to claim 1, wherein the first charging means charges the first image bearing member by making contact with the first image bearing member.
6. An apparatus according to claim 1, wherein when the second mode is selected, a black image is transferred to the transfer medium from the second image bearing member.
7. An apparatus according to claim 1, wherein the image transferred to the transfer medium is further transferred to a recording member.
8. An apparatus according to claim 1, wherein when the first mode is selected, the vibrating voltage applied to the first and the second charging means includes a DC voltage.
9. An apparatus according to claim 1, wherein the vibrating voltage applied to the first and the second charging means includes a DC voltage having the same polarity as the charge polarity of toner.
10. An apparatus according to any one of claims 1 to 9, wherein when the second mode is selected, the vibrating voltage applied to the first charging means includes a DC voltage.
11. An apparatus according to claim 10, wherein when the second mode is selected, the vibrating voltage applied to the second charging means includes a DC voltage.
12. An image forming apparatus comprising:
a first image bearing member;
first charging means for charging the first image bearing member, a vibration voltage being applied to the first charging means;
a second image bearing member; and
second charging means for charging the second image bearing member, a vibration voltage being applied to the second charging means,
wherein a first mode in which images formed on the first image bearing member and the second image bearing member are transferred to a transfer medium and a second mode in which the image formed on the second image bearing member is transferred to the transfer medium without forming the image on the first image bearing member are selectable, and
wherein when the second mode is selected, the magnitude of the vibration voltage frequency applied to the first charging means is smaller than the vibration voltage frequency applied when the first mode is selected.
13. An apparatus according to claim 12, wherein when the second mode is selected, the magnitude of the vibration voltage frequency applied to the first charging means is zero.
14. An apparatus according to claim 12, wherein the first charging means charges the first image bearing member by making contact with the first image bearing member.
15. An apparatus according to claim 12, wherein when the second mode is selected, a black image is transferred to the transfer medium from the second image bearing member.
16. An apparatus according to claim 12, wherein an image transferred to the transfer medium is further transferred to a recording member.
17. An apparatus according to claim 12, wherein when the first mode is selected, the vibrating voltage applied to the first and the second charging means includes a DC voltage.
18. An apparatus according to claim 12, wherein the vibrating voltage applied to the first and the second charging means includes a DC voltage having the same polarity as the charge polarity of toner.
19. An apparatus according to any one of claims 12 to 18, wherein when the second mode is selected, the vibrating voltage applied to the first charging means includes a DC voltage.
20. An apparatus according to claim 19, wherein when the second mode is selected, the vibrating voltage applied to the second charging means includes a DC voltage.