Available image transformations (rotation and/or mirroring).
IG_REC_IMG_ROTATE_AUTO | Automatic image rotation (Default). |
IG_REC_IMG_ROTATE_NO | Do not transform the image. |
IG_REC_IMG_ROTATE_RIGHT | Rotate image to the right (clockwise). |
IG_REC_IMG_ROTATE_DOWN | Rotate image down (rotate twice). |
IG_REC_IMG_ROTATE_LEFT | Rotate image to the left (anti-clockwise). |
IG_REC_IMG_ROTATE_FLIPPED | Mirror image without rotation (mirrored around the Y-axis). |
IG_REC_IMG_ROTATE_RIGHT_FLIPPED | Mirror image, then rotate to the right. |
IG_REC_IMG_ROTATE_DOWN_FLIPPED | Mirror image, then rotate twice. |
IG_REC_IMG_ROTATE_LEFT_FLIPPED | Mirror image, then rotate to the left. |
Rotation is always carried out in 90-degree steps. The following table shows the results of the image transformation using different values.
Original image:
Transformed image:
NO: | LEFT: | RIGHT: | DOWN: |
---|---|---|---|
123 | 369 | 741 | 987 |
456 | 258 | 852 | 654 |
789 | 147 | 963 | 321 |
FLIPPED: | LEFT_FLIPPED: | RIGHT_FLIPPED: | DOWN_FLIPPED: |
321 | 147 | 963 | 789 |
654 | 258 | 852 | 456 |
987 | 369 | 741 | 123 |
Automatic image rotation settings (IG_REC_IMG_ROTATE_AUTO) can only be used with good quality machine-printed texts, but not with images containing 9-pin dot-matrix text or other non-machine printed text. Mirroring values (those with the suffix FLIPPED) are ignored during image pre-processing IG_REC_image_preprocess. They are available only through IG_REC_image_orient.