fix: correct search upper bound

antecedent/pipeline.py

@@ -56,7 +56,7 @@ class JPEGPipeline:
     def define_upper_bound(self):
         self.upper_bound = np.zeros((self.quant_tbl.shape[0])).reshape(-1, 1, 1)
         if self.target_is_dct:
-            self.upper_bound += np.linalg.norm(self.quant_tbl, axis=(1, 2), ord='fro', keepdims=True)
+            self.upper_bound += np.linalg.norm(self.quant_tbl / 2, axis=(1, 2), ord='fro', keepdims=True)
         else:
             self.upper_bound += 4
         if not self.grayscale:
@@ -204,7 +204,7 @@ class FloatPipeline(JPEGPipeline):
 class ComposedPipeline:
     def __init__(self, pipelines, backward_naive=True):
         self.pipelines = pipelines
-        self.upper_bound = np.sum([pipe.upper_bound for pipe in pipelines], axis=0)
+        self.upper_bound = np.sum([pipe.upper_bound for pipe in pipelines], axis=0) + 1
         if backward_naive:
             self.backward_pipes = [
                 NaivePipeline(pipe.quality, pipe.target_is_dct, pipe.grayscale, return_int=False, return_rounded=False)