Merge pull request #1163 from CounterPillow/optimizeimg-fixes

Add jpegoptim interface to optimizeimages

docs/config.rst

@@ -683,8 +683,8 @@ Image options
         Using image optimizers will increase render times significantly.
 
     This option specifies which additional tools overviewer should use to
-    optimize the filesize of png tiles.
-    The tools used must be placed somewhere, where overviewer can find them, for
+    optimize the filesize of rendered tiles.
+    The tools used must be placed somewhere where overviewer can find them, for
     example the "PATH" environment variable or a directory like /usr/bin.
 
     The option is a list of Optimizer objects, which are then executed in
@@ -766,6 +766,34 @@ Image options
 
             **Default:** ``False``
 
+    ``jpegoptim``
+        jpegoptim can do both lossy and lossless JPEG optimisation. If no options are specified,
+        jpegoptim will only do lossless optimisations.
+        Available settings:
+
+        ``quality``
+            A number between 0 and 100 that corresponds to the jpeg quality level. If the input
+            image has a lower quality specified than the output image, jpegoptim will only do
+            lossless optimisations.
+            
+            If this option is specified and the above condition does not apply, jpegoptim will
+            do lossy optimisation.
+
+            **Default:** ``None`` *(= Unspecified)*
+
+        ``target_size``
+            Either a percentage of the original filesize (e.g. ``"50%"``) or a target filesize
+            in kilobytes (e.g. ``15``). jpegoptim will then try to reach this as its target size.
+
+            If specified, jpegoptim will do lossy optimisation.
+
+            .. warning::
+                This appears to have a greater performance impact than just setting ``quality``.
+                Unless predictable filesizes are a thing you need, you should probably use ``quality``
+                instead.
+
+            **Default:** ``None`` *(= Unspecified)*
+
     **Default:** ``[]``
 
 Zoom

overviewer_core/optimizeimages.py

@@ -121,6 +121,42 @@ class optipng(Optimizer, PNGOptimizer):
     def is_crusher(self):
         return True
 
+class jpegoptim(Optimizer, JPEGOptimizer):
+    binaryname = "jpegoptim"
+    crusher = True
+    quality = None
+    target_size = None
+
+    def __init__(self, quality = None, target_size = None):
+        if quality is not None:
+            if quality < 0 or quality > 100:
+                raise Exception("Invalid target quality %d for jpegoptim" % quality)
+            self.quality = quality
+
+        if target_size is not None:
+            self.target_size = target_size
+
+    def optimize(self, img):
+        args = [self.binaryname, "-q", "-p"]
+        if self.quality is not None:
+            args.append("-m" + str(self.quality))
+
+        if self.target_size is not None:
+            args.append("-S" + str(self.target_size))
+
+        args.append(img)
+
+        Optimizer.fire_and_forget(self, args)
+
+    def is_crusher(self):
+        # Technically, optimisation is lossless if input image quality
+        # is below target quality, but this is irrelevant in this case
+        if (self.quality is not None) or (self.target_size is not None):
+            return False
+        else:
+            return True
+
+        
 
 def optimize_image(imgpath, imgformat, optimizers):
         for opt in optimizers: