diff options
| -rwxr-xr-x | gerbimg.py | 37 |
1 files changed, 32 insertions, 5 deletions
@@ -21,7 +21,7 @@ def paste_image( outline_gerber:str, source_img:np.ndarray, subtract_gerber:list=[], - extend_overlay_r_mil:float=12, + extend_overlay_r_mil:float=6, extend_picture_r_mil:float=2, status_print=lambda *args:None, debugdir:str=None): @@ -32,21 +32,26 @@ def paste_image( cv2.imwrite(path.join(debugdir, '{:02d}{}.png'.format(debugctr, name)), img) debugctr += 1 + # Parse outline layer to get bounds of gerber file status_print('Parsing outline gerber') outline = gerber.loads(outline_gerber) (minx, maxx), (miny, maxy) = outline.bounds grbw, grbh = maxx - minx, maxy - miny status_print(' * outline has offset {}, size {}'.format((minx, miny), (grbw, grbh))) + # Read source image imgh, imgw = source_img.shape scale = math.ceil(max(imgw/grbw, imgh/grbh)) # scale is in dpi - status_print(' * source image has size {}, going for scale {}dpi'.format((imgw, imgh), scale)) + status_print(' * source image has size {}, going for scale {}dpmm'.format((imgw, imgh), scale)) + # Parse target layer status_print('Parsing target gerber') target = gerber.loads(target_gerber) (tminx, tmaxx), (tminy, tmaxy) = target.bounds status_print(' * target layer has offset {}, size {}'.format((tminx, tminy), (tmaxx-tminx, tmaxy-tminy))) + # Render all gerber layers whose features are to be excluded from the target image, such as board outline, the + # original silk layer and the solder paste layer to binary images. with tempfile.TemporaryDirectory() as tmpdir: img_file = path.join(tmpdir, 'target.png') @@ -64,19 +69,38 @@ def paste_image( status_print('Rendering keepout composite') ctx.dump(img_file) - original_img = cv2.imread(img_file, cv2.IMREAD_GRAYSCALE) + # Vertically flip exported image + original_img = cv2.imread(img_file, cv2.IMREAD_GRAYSCALE)[::-1, :] - status_print('Expanding keepout composite') - r = 1+2*max(1, int(extend_overlay_r_mil/1000 * scale)) + r = 1+2*max(1, int(extend_overlay_r_mil/1000 * 25.4 * scale)) + status_print('Expanding keepout composite by', r, extend_overlay_r_mil/1000 * 25.4 * scale, scale, grbw, grbh) + + # Extend image by a few pixels and flood-fill from (0, 0) to mask out the area outside the outermost outline + # This ensures no polygons are generated outside the board even for non-rectangular boards. + border = 10 + outh, outw = original_img.shape + extended_img = np.zeros((outh + 2*border, outw + 2*border), dtype=np.uint8) + extended_img[border:outh+border, border:outw+border] = original_img + cv2.floodFill(extended_img, None, (0, 0), (255,)) + original_img = extended_img[border:outh+border, border:outw+border] + debugimg(extended_img, 'flooded') + + # Dilate the white areas of the image using gaussian blur and threshold. Use these instead of primitive dilation + # here for their non-directionality. target_img = cv2.blur(original_img, (r, r)) _, target_img = cv2.threshold(target_img, 255//(1+r), 255, cv2.THRESH_BINARY) + # Threshold source image. Ideally, the source image is already binary but in case it's not, or in case it's not + # exactly binary (having a few very dark or very light grays e.g. due to JPEG compression) we're thresholding here. status_print('Thresholding source image') qr = 1+2*max(1, int(extend_picture_r_mil/1000 * scale)) source_img = source_img[::-1] _, source_img = cv2.threshold(source_img, 127, 255, cv2.THRESH_BINARY) debugimg(source_img, 'thresh') + # Pad image to size of target layer images generated above. After this, `scale` applies to the padded image as well + # as the gerber renders. For padding, zoom or shrink the image to completely fit the gerber's rectangular bounding + # box. Center the image vertically or horizontally if it has a different aspect ratio. status_print('Padding source image') tgth, tgtw = target_img.shape padded_img = np.zeros(shape=target_img.shape, dtype=source_img.dtype) @@ -90,11 +114,13 @@ def paste_image( debugimg(padded_img, 'padded') debugimg(target_img, 'target') + # Mask out excluded gerber features (source silk, holes, solder mask etc.) from the target image status_print('Masking source image') out_img = (np.multiply((padded_img/255.0), (target_img/255.0) * -1 + 1) * 255).astype(np.uint8) debugimg(out_img, 'multiplied') + # Calculate contours from masked target image and plot them to the target gerber context status_print('Calculating contour lines') plot_contours(out_img, target, @@ -102,6 +128,7 @@ def paste_image( scale=scale, status_print=lambda *args: status_print(' ', *args)) + # Write target gerber context to disk status_print('Generating output gerber') from gerber.render import rs274x_backend ctx = rs274x_backend.Rs274xContext(target.settings) |