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1. #PILLOW IMAGE CONVERT GRAYSCLAE HOW TO#
2. #PILLOW IMAGE CONVERT GRAYSCLAE FULL SIZE#
3. #PILLOW IMAGE CONVERT GRAYSCLAE CODE#

Finally we convert the image back to ‘RGB’ as according to Lundh, this allows us to save the image as a Jpeg. Then we apply our sepia palette using the putpalette() method of the image object. Next we convert our image to black and white (or gray scale depending on how you look at it). This creates a good sized tuple of various RGB values that represents out sepia palette. To create the palette, we need an off-white color created, so we do that by iterating over a tuple that is off-white and then iterating over all 255 variations of the RGB color spectrum. One for creating the sepia palette and the other for applying it.

#PILLOW IMAGE CONVERT GRAYSCLAE HOW TO#

I went digging around the web and found an article on Fredrik Lundh’s site that talked about how to do this trick. Sepia toned images are pretty popular and give your image that old fashioned yellowed look. Now that we’ve learned how to make our images black and white, I wanted to talk about how to add a sepia toning to your image. It’s almost an ink-blot! As you can see, when it comes to creating black and white images, ‘L’ is probably the mode you will want to focus on. This one is a bit abstract looking, but also kind of interesting. If you do that, you will see the following image: Now let’s call the function with dithering set to False. However since I am using a small version here, the change is pretty subtle.

#PILLOW IMAGE CONVERT GRAYSCLAE FULL SIZE#

This one looks a lot different when you have the image at full size because you can see the white noise a lot easier. You can do dithering with the ‘L’ mode, but I wanted to show what happens when you use ‘1’. The only difference between this function and the previous one is that we added a dithering argument and we also called the convert() method with a ‘1’ (one) instead of ‘L’.

Let’s take a look at how that changes the code:ĭef black_and_white_dithering(input_image_path,īw = color_nvert('1', dither=Image.NONE) The Pillow project also supports creating black and white images with dithering, which is basically adding noise to the image.

That looks pretty nice if I do say so myself.

#PILLOW IMAGE CONVERT GRAYSCLAE CODE#

Let’s see what kind of output our code generated: The documentation states “When translating a color image to black and white (mode “L”), the library uses the ITU-R 601-2 luma transform: L = R * 299/1000 + G * 587/1000 + B * 114/1000” where the RGB maps to Red, Green and Blue. The mode we care about at the moment is ‘L’.

Pillow supports several modes including: ‘P’, ‘L’ and ‘1’. Here you will find that the first parameter to the convert() method is the mode. This may seem a bit strange, so let’s look at the documentation. We then use that object’s convert method to transform the image to black and white by passing it the string ‘L’. It contains a call to open the Image which will return an Image object. The piece we really care about in this script is this function. The function above takes two arguments: the input image’s file path and the path we want to save the output to. Now we just need to create a simple function that can turn our full color photo into a black and white one:Ĭolor_image = Image.open(input_image_path) For this example, we will use the following fuzzy caterpillar: The first obstacle is finding a photo that you would like to edit. In this article we will look at the two simple ways to convert a photo to black and white and then we will also learn how to make a sepia-toned photo. If you want to change a photo that you took into a black and white photo programmatically, the Pillow package has you covered. I have also rescued a drab photo by turning it black and white. I personally like to play around with them as you can sometimes take a boring photo and turn it into something dramatic. Black and white images aren’t for everyone.