Document reading apparatus AND IMAGE FORMING APPARATUS INCLUDING SAME

The document reading apparatus performs gradation conversion when reading a color image of a document and converting the color image into a gradation image so as to reduce black stripes appearing in the gradation image formed on recording paper. The document reading apparatus includes: a reading section including photoelectric conversion elements of red R, green G, and blue B, the photoelectric conversion elements being used to read a color image of a document; and a conversion unit for converting the read color image into a gradation image, the conversion unit setting, as the gradation valueof the pixel, the gradation value MAX (RGB) having the largest value among the gradation values of the colors of the RGB signal (RGB) of the pixel comprising the three colors of red R, green G, and blue B. 原稿读取装置在读取原稿的彩色图像并将其转换为灰度图像时进行灰度转换，以使形成在记录纸上的灰度图像中出现的黑条变淡并减少。原稿读取装置包括：读取部，包括红R、绿G及蓝B的光电转换元件，使用这些光电转换元件来读取原稿的彩色图像；以及转换部，将所述读取的彩色图像转换为灰度图像，所述转换部将由所述红R、绿G及蓝B这三种颜色构成的像素的RGB信号(RGB)的各色的色阶值中的值最大的色阶值MAX(RGB)设定为所述像素的灰度值。