gimp support being scripted with python (2.7) menu Filters > Python Fu > console, you don’t even need to write a plugin, just type execfile("/some/path/your-script.py") to the console prompt
the python console have a very nice Browse button which allow to find the functions you need from the procedure browser (and their arguments), those may be exported from gimp or plugins
For example, I needed to crop each layer and save it as png file, save the name of the layer and the crop coordinates in a json file, here it is:
savepath="/tmp/slices/"
f=open("{0}images.json".format(savepath),"w")
print >> f, "["
def process_layer(image, layer):
pdb.gimp_image_set_active_layer(image, layer)
drawable = pdb.gimp_image_active_drawable(image)
layer_name = pdb.gimp_item_get_name(drawable)
if layer_name == "background":
return
pdb.gimp_selection_none(image)
pdb.gimp_context_set_sample_merged(FALSE)
pdb.gimp_context_set_antialias(FALSE)
pdb.gimp_context_set_sample_transparent(TRUE)
pdb.gimp_context_set_feather(FALSE)
pdb.gimp_context_set_sample_threshold(0)
pdb.gimp_image_select_contiguous_color(image, 2, drawable, 1, 1)
pdb.gimp_selection_invert(image)
non_empty, x1, y1, x2, y2 = pdb.gimp_selection_bounds(image)
if non_empty:
pdb.gimp_image_select_rectangle(image, 2, x1, y1, x2-x1, y2-y1)
non_empty = pdb.gimp_edit_copy(drawable)
if non_empty:
image4 = pdb.gimp_edit_paste_as_new()
active_layer = pdb.gimp_image_get_active_layer(image4)
pdb.file_png_save2(image4, active_layer, "{0}{1}.png".format(savepath, layer_name), layer_name, TRUE, 9, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE)
pdb.gimp_image_delete(image4)
print >> f, "\t{{ \"{0}\": [ {1:d}, {2:d}, {3:d}, {4:d} ] }},".format(layer_name, x1, y1, x2, y2)
else:
print("gimp_edit_copy = empty ({0})".format(layer_name))
else:
print("gimp_selection_bounds = empty ({0})".format(layer_name))
image = gimp.image_list()[0]
for layer in image.layers:
process_layer(image, layer)
print >> f, "]"
f.close()