.image() support bitmap images

elsie/box.py

@@ -1,8 +1,11 @@
 import logging
 
 import lxml.etree as et
+import base64
+from PIL import Image
+import io
 
-from .draw import draw_text
+from .draw import draw_text, draw_bitmap
 from .geom import Rect
 from .highlight import highlight_code
 from .image import get_image_steps, create_image_data
@@ -45,6 +48,19 @@ def set_paint_style(xml, color, bg_color, stroke_width, stroke_dasharray):
     xml.set("style", ";".join(styles))
 
 
+def scaler(rect, image_width, image_height):
+    scale_x = rect.width / image_width
+    scale_y = rect.height / image_height
+
+    if rect.width and rect.height:
+        return min(scale_x, scale_y)
+    elif rect.width:
+        return scale_x
+    elif rect.height:
+        return scale_y
+    return None
+
+
 class Box:
 
     def __init__(self,
@@ -268,6 +284,46 @@ def _render_svg(self, ctx, x, y, scale, data):
         ctx.xml.close()
 
     def image(self, filename, scale=None, fragments=True, show_begin=1):
+        """ Draw an svg/png/jpeg image, detect by extension """
+        if filename.endswith("svg"):
+            self.image_svg(filename, scale, fragments, show_begin)
+        elif any(filename.endswith(ext) for ext in [".png", ".jpeg", ".jpg"]):
+            self._image_bitmap(filename, scale)
+        else:
+            raise Exception("Unkown image extension")
+        return self
+
+    def _image_bitmap(self, filename, scale):
+
+        with open(filename, "rb") as f:
+            data = f.read()
+
+        img = Image.open(io.BytesIO(data))
+        mime = Image.MIME[img.format]
+        image_width, image_height = img.size
+        del img
+
+        data = base64.b64encode(data).decode("ascii")
+
+        def draw(ctx, rect):
+            if scale is None:
+                s = scaler(rect, image_width, image_height)
+                if s is None:
+                    logging.warning(
+                        "Scale of image {} is 0, set scale explicitly or set at least one "
+                        "dimension for the parent box".format(filename))
+            else:
+                s = scale
+
+            w = image_width * s
+            h = image_height * s
+            x = rect.x + (rect.width - w) / 2
+            y = rect.y + (rect.height - h) / 2
+            draw_bitmap(ctx.xml, x, y, w, h, mime, data)
+
+        self.add_child(draw)
+
+    def _image_svg(self, filename, scale=None, fragments=True, show_begin=1):
         """ Draw an svg image """
 
         root = et.parse(filename).getroot()
@@ -298,17 +354,8 @@ def draw(ctx, rect):
                 data = image_data
 
             if scale is None:
-                scale_x = rect.width / image_width
-                scale_y = rect.height / image_height
-
-                s = 0
-                if rect.width and rect.height:
-                    s = min(scale_x, scale_y)
-                elif rect.width:
-                    s = scale_x
-                elif rect.height:
-                    s = scale_y
-                else:
+                s = scaler(rect, image_width, image_height)
+                if s is None:
                     logging.warning(
                         "Scale of image {} is 0, set scale explicitly or set at least one "
                         "dimension for the parent box".format(filename))
@@ -323,8 +370,6 @@ def draw(ctx, rect):
 
         self.add_child(draw)
 
-        return self
-
     def code(self, language, text, tabsize=4, line_numbers=False, style="code"):
         """ Draw a code with syntax highlighting """
 

elsie/draw.py

@@ -67,3 +67,13 @@ def draw_text(xml, x, y, parsed_text, style, styles, id=None):
     for s in active_styles:
         xml.close("tspan")
     xml.close("text")
+
+
+def draw_bitmap(xml, x, y, width, height, mime, data):
+    xml.element("image")
+    xml.set("x", x)
+    xml.set("y", y)
+    xml.set("width", width)
+    xml.set("height", height)
+    xml.set("xlink:href", "data:{};base64,{}".format(mime, data), escape=False)
+    xml.close("image")

elsie/image.py

@@ -36,4 +36,4 @@ def find_hidden_elements(element):
     find_hidden_elements(root)
     for element, child in hidden:
         element.remove(child)
-    return et.tostring(root).decode()
+    return et.tostring(root).decode()

elsie/sxml.py

@@ -23,9 +23,10 @@ def element(self, name):
         self.stack.append(name)
         self.is_open = True
 
-    def set(self, name, value):
+    def set(self, name, value, escape=True):
         assert self.is_open
-        value = str(value).replace("'", "\\'")
+        if escape:
+            value = str(value).replace("'", "\\'")
         self.chunks.append(" {}='{}'".format(name, escape_text(value)))
 
     def text(self, text):

tests/test_image.py

@@ -65,3 +65,22 @@ def test_image_scale_width_height(test_env):
 def test_image_scale_no_dimensions(test_env):
     test_env.slide.box().image(test_env.data_path("scale.svg"))
     test_env.check("scale-no-dimensions")
+
+def test_image_bitmap(test_env):
+    slide = test_env.slide
+    img_png = test_env.data_path("imgs/test.png")
+    img_jpg = test_env.data_path("imgs/test.jpeg")
+
+    b = slide.fbox(height=140)
+    b.rect(bg_color="green")
+    b.image(img_png)
+
+    b = slide.fbox(height=300)
+    b.rect(bg_color="blue")
+    b.image(img_png)
+
+    b = slide.fbox(height=300)
+    b.rect(bg_color="green")
+    b.image(img_jpg)
+
+    test_env.check("image-bitmap", 1)