diff --git a/CHANGELOG.md b/CHANGELOG.md
index dc3ec73..d0702a1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Fixed
 
+- 'ValueError': when bmp images with 1 bit channel are decoded ([#773](https://github.com/pdfminer/pdfminer.six/issues/773))
 - `ValueError` when trying to decrypt empty metadata values ([#766](https://github.com/pdfminer/pdfminer.six/issues/766))
 - Sphinx errors during building of documentation ([#760](https://github.com/pdfminer/pdfminer.six/pull/760))
 - `TypeError` when getting default width of font ([#720](https://github.com/pdfminer/pdfminer.six/issues/720))
diff --git a/pdfminer/utils.py b/pdfminer/utils.py
index 599d57b..59cf5cd 100644
--- a/pdfminer/utils.py
+++ b/pdfminer/utils.py
@@ -132,7 +132,7 @@ def apply_png_predictor(
 
     Documentation: http://www.libpng.org/pub/png/spec/1.2/PNG-Filters.html
     """
-    if bitspercomponent != 8:
+    if bitspercomponent not in [8, 1]:
         msg = "Unsupported `bitspercomponent': %d" % bitspercomponent
         raise ValueError(msg)